Almost every resident of the city at least once saw on his streets passing tram or other similar electric transport. Such variants of the means of movement were specially designed for movement by such conditions. In fact, the device tram strongly resembles ordinary railway transport. However, their differences are precisely in adaptability for different types of terrain.

History of appearance

The name itself is translated from English as a combination of the car (trolley) and the path. It is considered that the tram is one of the oldest types of passenger public transport, which still applies in many countries around the world. The history of the appearance dates back to the 19th century. It is worth noting that the oldest tram worked on horse riding, and not on electricity. The more technological progenitor was invented and tested by Fedor Pyroatsky in St. Petersburg in 1880. After another year, the German company Siemens & Halske launched the first existing tram message in the suburb of Berlin.

During the two world wars, this transport fell into decline, nevertheless, since the 1970s, its popularity has recently increased. The reasons for this were environmental considerations and new technologies. At the heart of the tram lay the electric junction on the air subsequently, new ways of bringing the car in motion were created.

Evolution trams

All species unites what they work on electricity. The exception is only less popular cable (cable) and diesel trams. Previously, equestrian, pneumatic, petrol and steam species were also created and experienced. Traditional electric trams operate either on an air contact network or with power from batteries or contact rail.

The evolution of this type of transport led to its division into types for its intended purpose, including passenger, cargo, service and special. The last type includes many subtypes like a mobile power plant, technical pavement, wagon-crane and a compressor wagon. For passengers, the tram device also depends on the system on which it moves. She, in turn, can be urban, suburban or long-distance. In addition, systems are divided into ordinary and high-speed, which may include underground laying options with tunnels.

Power supply tram

At the dawn of development, each infrastructure service company connected its own power plant. The fact is that networks of those times have not yet had enough power, and therefore had to do with their own means. All trams feed on a constant current with a relatively low voltage. For this reason, the charge of long distances is very ineffective with a financial point of view. To improve the infrastructure of networks near the lines began to have traction substations, converting alternating current in constant.

To date, the rated voltage at the exit was set at a mark of 600 V. The mobile composition of the tram on the current receiver receives 550 V. In other countries, the increased values \u200b\u200bof the voltage - 825 or 750 V. The latter is the most relevant in European countries at the current moment. As a rule, tram networks have a common power plant with trolley buses, if any in the city.

Description of traction engine

This type is used most often. Previously, only the constant current received from substations was used for the substitution. However, modern electronics made it possible to create special converters inside the design. Thus, when answering the question about which engine from the tram in its modern version should also be mentioned about the possibility of using an alternating current-based engine. The last is better for the reason that it practically does not require any repair or regular service. This concerns, of course, only asynchronous AC motors.

Also in the design certainly includes another important node - the control system. Another common name sounds like a current control device through the TED. The most popular and simple version of the option is considered to be controlled by means of powerful resistance that are consistently connected to the engine. From varieties used NSS, indirect non-automatic RKSU or indirect automatic RCSU system. There are also separate types such as teis or transistor Su.

The number of wheels in the tram

Low-full variations of this vehicle are extremely distributed. Features of the design do not give the ability to make an independent suspension for each wheel, which is why special wheeled pairs are required. Alternative solutions of this problem also apply. The number of wheels depends on the specific embodiment of the design of the tram and - to a greater extent - from the number of sections.

Also, the layout differs. Most multisective trams are equipped with drive wheeled pairs (which have a motor) and non-extended. To increase turns, the number of compartments usually increase. If you are interested in how many wheels in the tram, you can find the following information:

1. One section. Two or four drives or two drive and one non-war steam wheels.
2. Two sections. Four drive and two non-extended or eight drive pairs of wheels.
3. Three sections. Four driven and non-war steam wheels in different combinations.
4. Five sections. Six drive pairs of wheels. Go two pieces through one section starting with the first.

Features of driving tram

It is considered relatively simple, because the transport moves strictly along the rails. This means that as such a manual control from the tram driver is not required. At the same time, the car trades should be able to competently use the thrust and braking, which is achieved by the timely switching of the rear and forehead.

The rest of the tram is subordinate to the unified rules of the road at a time when it follows the city streets. In most cases, this transport has priority to vehicles and other means of movement that do not depend on the rail. The tram driver must necessarily obtain the right to drive the appropriate category and pass the theoretical exam on the knowledge of traffic rules.

General device and design

The body of modern representatives is usually performed from solid metal, and it is emitted as separate elements a frame, frame, doors, floor, roof, as well as inner and outer sheat. To the ends, the form, as a rule, narrows, thanks to which the tram with ease overcomes curves. The connection of the elements is carried out by welding, riveting, with screws and glue.

In the past times, wood was also widely used, which served as an element of the frame and the material for decoration. In the tram device, the preference is given to plastic elements. The design also includes turning signals, brake lights and other means to indicate to other participants in motion.

Coordination and speed indicators

Just as in the case of trains, this transport has its own traffic tracking service and routes correct. Dispatchers are engaged in operational adjustment of the schedule if any unexpected situation on the line has happened. Also, this service is responsible for the release of backup trams or buses for replacement.

Rules of movement in urban conditions may differ in different countries. For example, in Russia the estimated velocity tram lies in the range from 45 to 70 km / h, and for systems at operating speed from 75 to 120 km / h, construction norms prescribe "high-speed" console.

Pneumatic equipment

Wagons in modern execution them are often equipped with special compressors, which are based on pistons. Compressed air is very useful immediately for several regular operations, including actuating door drives, brake systems and other auxiliary mechanisms.

In this case, the presence of pneumatic equipment is not mandatory. Due to the fact that the tram device assumes constant power supply, these structural elements can be replaced with electrical. This is noticeably simplified by maintenance of systems, but some extent grows the final cost of producing one car.

The tram is the type of urban (in rare cases of the suburban) of the passenger (in some cases of freight) of transport with the maximum permissible load on line up to 30,000 passengers per hour, in which the car (composition from the wagons) is driven by rails due to electrical energy.

Currently, the term easier tram (LRT) is also often used to modern trams. Trams arose at the end of the XIX century. After the heyday, the epoch of which fell for the period between world wars, the decline of trams began, but since the end of the XX century there is a significant increase in the tram popularity. The Voronezh tram was solemnly opened on May 16, 1926 - you can read about this event in detail in the Story section, the classic tram was closed on April 15, 2009. The average plan of the city involves restoring the tram movement on all the directions that existed until recently.

Tram device
Modern trams are very different from their design predecessors, however, the basic principles of the tram device, which generate its advantages over other types of transport, remained unchanged. The wagon electrochem is arranged approximately as follows: a current (pantograph, bougiel, or bar) - a traction engine control system - traction engines (TED) - rails.

A traction engine control system is designed to change the current flow passing through the TED - that is, to change the speed. A direct control system was used on old cars: a driver controller was in the cockpit - a round cabinet with a handle at the top. When turning the handle (there were several fixed positions), a certain proportion of current force was fed to the traction motor. In this case, the rest turned into heat. Now there are no such cars left. Since the 60s, the so-called Painting Contactor Contactor Control System (RCSU) began to be applied. The controller was divided into two blocks and became more complex. The possibility of parallel and consistent inclusion of traction engines appeared (as a result, the car develops different speeds), and intermediate rosight positions - thus, the process of overclocking has become much smaller. The possibility of clutching cars on the system of many units is when the management of all engines and electrical circuits of cars is carried out from one post of the machine. From the 1970s and to the present, the height of the control systems performed on the semiconductor element base are introduced throughout the world. The engine is fed with a frequency of several tens times per second current pulses. This allows you to achieve a very high smoothness of the stroke and high electricity savings. Modern trams equipped with a thyristor-pulsed control system (such as Voronezh KTM-5RM or former until 2003 in Voronezh Tatry-T6B5), additionally save up to 30% of electricity due to tees.

The principles of tram braking are similar to similar in railway transport. On the old trams of the brakes were pneumatic. The compressor produced compressed air, and with the help of a special system of devices, its energy pressed the brake pads to wheels - as well as on the railway. Now pneumothormosis is used only on the cars of the St. Petersburg Tram-Mechanical Plant (PTMZ). Since the 1960s, electrodynamic braking is mainly used on trams. Traction engines in braking produce a current, which on risostats (many successively connected resistors) turns into thermal energy. For braking at low speeds, when electric motors are inefficient (with a complete stop of the wagon), booming brakes acting on wheels are used.

Low-voltage chains (for lighting, alarm system and all this) are powered by electric transducers (or motor generators - of the one that is constantly buzzing on the tatra-t3 and KTM-5 cars) or from silent semiconductor transducers (CTM-8, Tatra-T6V5 , KTM-19 and so on).

Tram management

Approximately the control process looks like this: the driver raises a pantograph (arc) and turns on the car, gradually turning the controller knob (on the CTM cars), or presses the pedal (on the tatras), the circuit is automatically collected on the course, the traction engines come increasingly and larger current, And the car is accelerated. Upon reaching the required speed, the driver sets the controller knob to the zero position, turns off the current, and the car moves along the inertia. Moreover, unlike gell transport, it can move for quite a long time (it saves a huge amount of energy). To brake, the controller is installed on the braking position, the diagram is collected for braking, the tests are connected to the risostats, and the wagon begins to be braked. When the speed is reached about 3-5 km / h, mechanical brakes automatically turn on.

In key points of the tram network - as a rule, in the area of \u200b\u200bthe roof rings or development - there are dispatching points that control the operation of tram cars and comply with its pre-compiled schedule. For lateness and overtaking schedules Tram drivers are subjected to fines - this feature of the organization's organization significantly increases predictability for passengers. In cities with a developed tram network, where the tram is now the main carrier of passengers (Samara, Saratov, Yekaterinburg, Izhevsk and others) passengers tend to stop from work and to work, in advance of the arrival of the coming car. Behind the movement of trams in the entire system watches the central dispatcher. In the case of accidents on the lines, the dispatcher on the centralized communication system indicates the paths of the detachment, which is distinguished by the tram from its closest relative - the metro.

Travel and electric farm

In different cities, trams use different width of the gauge, most often - the same as ordinary railways, such as, for example, in Voronezh - 1524 mm. For a tram in different conditions, both ordinary railway-type rails can be used (only in lack of paving) and special tram (grooved), with a fruit and a sponge that can drown the rail in the pavement. In Russia, tram rails are made of softer steel so that the curves of a smaller radius can be made than on the railway.

To change the traditional - paddle-laying rail, more and more often apply a new, in which the rail is placed in a special rubber chute located in a monolithic concrete plate (in Russia such technology is called Czech). Despite the fact that such laying of the way costs more, laid so the rail path serves without repair much longer, the vibration and noise from the tram line completely extends, eliminates wandering currents; Moving the line laid on modern technology does not represent difficulties for motorists. The Lines of Czech technology exist now in Rostov-on-Don, Moscow, Samara, Kursk, Yekaterinburg, Ufa and other cities.

But even without the use of special technologies, the noise and vibrations from the tram line can be minimized due to the correct installation of the canvas and its timely service. The paths should be placed on the basis of rubble, on concrete spats, which must then be covered with rubble, after which the line asphalted or closes with concrete tiles (for noise absorption). The joints of the rails are welded, and the line itself is polished with the help of a relax-lifted car. Such cars were produced at the Voronezh Repair Tram Trolleybus Plant (UGTT) and are available not only in Voronezh, but also in other cities of the country. The noise from the line laid in this way does not exceed noise from the diesel engine of buses and trucks. The noise and vibrations from the car walking along the line laid on Czech technology, less noise produced by buses, by 10-15%.

In the early period of the development of trams, electrical networks have not yet had enough development, so almost every new tram service included its own central power plant. Now tram farms receive electricity from general-purpose electrical networks. Since the tram is powered by a constant current of a relatively low voltage, transmitting it over long distances is too expensive. Therefore, travelery substations are placed along the lines, which are obtained from the networks of high voltage, and convert it to a constant current suitable for feeding to the contact network. The rated voltage at the output of the traction substation - 600 volts, 550 V. is considered the rated voltage on the transmission of the rolling stock.

Motor high-blooded wagon x with an inspext trailer M on a revolution avenue. Such trams were two-axis, in contrast to the four-axle, used now in Voronezh.

CTM-5 tram car - four-axle high-hearted tram wagon of domestic production (VHF). Trams of this model launched into mass production in 1969. Since 1992, such trams have not been produced.

Modern four-axle high-hearted KTM-19 car (VHF). Such trams now make up the basis of the park in Moscow, they are actively purchased by other cities, including such cars there are in Rostov-on-Don, Stary Oskol, Krasnodar ...

Modern articulated low-blooded tram KTM-30 production of IVED. In the next five years, such trams should be the basis of a high-speed tram network created in Moscow.

Other features of the organization of tram traffic

The tram movement is distinguished by a large proportion ability of lines. Tram is the second transportation opportunities after the subway. So, the line of the traditional tram can take out passenger traffic at 15,000 passengers per hour, the high-speed tram line is capable of removing up to 30,000 passengers per hour, and the subway line is capable of removing - up to 50,000 passengers per hour. The bus and trolleybus are twice again by tram on the suspension - for them it is only 7,000 passengers per hour.

Tram, as well as all rail transport, has a greater intensity of the turnover of rolling stock (PS). That is, a smaller number of trams wagons than buses or trolleybuses to serve the same passenger traffic. The tram has the greatest among the facilities of ground urban transport by the efficiency of the use of urban area (the ratio of the number of passengers transported to the area occupied on the roadway). The tram can be used in coupling from several cars or in multi-meter articulated tram trains, which allows the mass of passengers to the forces of one driver. This further reduces the cost of such transportation.

It should also be noted a relatively long service life of the PS tram. The warranty period of the wagon to the capital and restoration repair is 20 years (unlike trolleybus or bus, where the service time without the CVW does not exceed 8 years), and after the KVD, the service life is extended as much. For example, in Samara there are tatra-t3 cars with a 40-year history. The cost of KVR Wagon tram is significantly lower than the purchase price of the new and is carried out, as a rule, by the TTU. This allows without any problems to acquire used cars abroad (at prices 3-4 times lower than the cost of the new car) and use them without problems of about 20 years on the lines. The purchase of used buses is associated with large trips to repair such equipment, and, as a rule, after purchase, such a bus cannot be used longer than 6-7 years. The factor of a significantly greater duration of the service and increased maintainability of the tram completely compensates for the high cost of acquiring a new PS. The presented value of the PS tram is almost 40% lower than for the bus.

Advantages tram

• Initial costs (when creating a tram system), though high, but nevertheless, they are lower than the costs needed for the construction of the subway, since there is no need to complete the lines (although the line can be held in the tunnels in the tunnels and the line , but there is no need to arrange them on the entire route). However, the construction of a terrestrial tram is usually associated with the reorganization of streets and intersections, which increases the price and leads to a deterioration in the road situation during construction.
• With passenger traffic, more than 5,000 pass. / Hour The tram operating is cheaper than the operating of the bus and trolley buses.
• Unlike buses, trams do not contaminate air combustion products and rubber dust from friction wheels on asphalt.
• Unlike trolleybuses, trams are more electrically safe and more economical.
• The tram line is covered in a natural way by depriving her road surface, which is important in conditions of low driver's culture. But even in conditions of high driver's culture and in the presence of a pavement, the tram line is noticeable better, which helps drivers to keep the highlighted band for public transport free.
• The trams fit well into the urban environment of different cities, including on Wednesday cities with a prevailing historical appearance. Different systems on the overpass, like Monorail and some types of lobes, from an architectural and town planning point of view, are well suited only for modern cities.
• The low flexibility of the tram network (provided its good condition) psychologically beneficial effects on real estate value. Real estate owners proceed from the fact that the presence of rails guarantees the presence of a tram message, as a result, the property will be provided with transport, which attracts a high price for it. According to the Bureau of Hass-Klau & Crampton, the cost of real estate in the area of \u200b\u200bthe tram lines increases by 5-15%.
• Trams provide greater vehicle ability than buses and trolley buses.
• Although the tram car is much more expensive than the bus and trolley buses, but trams are distinguished by a much larger service life. If the bus rarely serves longer than ten years, then the tram can be operated for 30-40 years, and subject to regular upgrades even at this age the tram will meet the requirements of comfort. So, in Belgium, along with modern low-profils, the trams of PCC, released in 1971-1974, are successfully operated. Many of them have recently been upgraded.
• The tram can combine high-speed and non-local sites within the same system, as well as to have the ability to lose emergency sites, in contrast to the metro.
• Tram wagons can be clutching into trains along the system of many units, which saves on wages.
• The tram, equipped with tees, saves up to 30% of electricity, and a tram system that allows to use recovery (return to the network when braking, when the electric motor operates as an electric generator) of electricity, additionally saves up to 20% of energy.
• According to statistics, the tram is the safest type of transport in the world.

Disadvantages of tram

• Although the tram line in the construction and cheaper subway, it is much more expensive than trolleybus and the more bus.
• The transport ability of trams is lower than that of the subway: 15,000 passengers per hour in the tram, and up to 30,000 passengers per hour in each direction at the easy metro.
• Tram rails are dangerous for careless cyclists and motorcyclists.
• Incorrectly parked car or road traffic accident can stop motion on a large portion of the tram line. In the event of a breakdown, its tram, as a rule, pushes into the depot or to the backup path, following it, the composition, which ultimately leads to a similarity from the line of two units of rolling stock at once. The tram network is distinguished by relatively low flexibility (however, it can be compensated by an extension of a network that makes a detour of obstacles). The bus network is very easy to change if necessary (for example, in the case of street repair). When using deobeus, the trolleybus network becomes very flexible. However, this deficiency is minimized when using the tram on a separate canvase.
• The tramway requires at least an inexpensive, but permanent service and is very sensitive to its absence. Restoration of the launched economy is very expensive.
• The laying of tram lines on the streets and roads requires a skillful placement of paths and complicates the organization of movement.
• The brake path tram is noticeably larger than the brake path of the car, which makes the tram a more dangerous member of the road on the combined canvase. However, according to statistics, the tram is the safest view of public transport in the world, while the route taxi is the most dangerous.
• The soil vibration caused by tram can create acoustic discomfort for the inhabitants of the surrounding buildings and lead to damage to their foundations. With regular maintenance of the path (grinding to eliminate wave-like wear) and rolling stock (wheelchair) vibrations can be strongly reduced, and when applying advanced technologies for laying paths are minimized.
• With a bad way in the path, the reverse traction current can go to the ground. "Wandering currents" reinforce corrosion of nearby underground metal structures (cable shells, sewage and water pipes, fittings for building foundations). However, with modern technology laying rails, they minimize.

General information about the tram.

The tram belongs to public electric transport, which is intended for the transport of passengers and compounds into a single whole area of \u200b\u200bthe city. The tram is driven by four powerful electric motors receiving power from the contact network and back in the rail and moving along the rail canvase.

The city uses the trams of the brand KTM Ust - Katavsky Carriage and Construction Plant. General information about rolling stock:

High movement speed, which is provided by four powerful electric motors, allowing to develop the maximum vehicle speed to 65 km / h.

Greater capacity is ensured due to a decrease in the number of seats and increasing the accumulative sites, as well as due to the compound of cars, the composition, and on new tram cars due to the articulation of the wagons by increasing their length and width. Thanks to this, their capacity fluctuates from 120 to 200 people.

Motion safety is ensured by rapidly acting brakes:

Electro-dynamic brake. Brakes due to the engine, used to clean the speed.

Emergency electro-dynamic brake. Used for quenching the speed if the voltage is lost in the contact network.

Drumbar brake. Used to stop the wagon and as a parking brake.

Rail brake. Used for emergency stop in an emergency.

Comfortability is ensured due to the subressing of the body, the installation of soft seats, heating and lighting.

All equipment is divided into mechanical and electric. By appointment there are passenger, cargo and special.

Special wagons are divided into snowy cleaning, rails and lubricants and laboratory wagons.

The main disadvantage of tram is a small maneuverity, if one rose that other trams behind him stopped.

Tram movement modes.

The tram moves in three modes: thrust, elevation and braking.

Traction mode.

The tram acts on the tram, it is created by four tractive electric motors and is directed towards the tram movement. Resistance strengths interfere with movement, it can be a counter wind, a rail profile or the technical condition of the tram. If the tram is faulty resistance strength increase. The weight of the car is directed down. Thereby providing the clutch of the wheel with the rail. The normal movement of the tram will be subject to the condition when the thrust force is less clutch (F traction< F сцепления), при этом колесо вращается и поступательно движется по рельсу. При плохих погодных условиях сила сцепления резко падает и сила тяги становиться больше силы сцепления (F тяги > F clutch), while the wheel starts to rotate on the spot, that is, begins to buck. When the contact wire is arson, the failure of the tram electrical equipment occurs, appear potholes on the rails. To stop there was not, with bad weather, the driver should smoothly translate the handle along the tram chassis positions.

Mail mode.

In the elevation mode, the engines are disconnected from the contact network and the tram moves by inertia. This mode is used to save electricity and to test the technical condition of the tram.

Brake mode.

In braking mode, brakes are turned on and brake force appears directional in the opposite side of the tram movement. Normal braking will be provided when braking force is less grip (F of braking< F сцепления). Тормоза останавливают вращательное движение колёс, но трамвай продолжает скользить по рельсам, то есть идти юзом. При движении юзом вагон становиться неуправляемым, что приводит к дорожно-транспортному происшествию (ДТП) и набиваются лыски на колесе.

Equipment tram car.

Body tram.

We need for the transport of passengers to protect against the external environment, provides security and serves to hide the equipment. The body is all-metal welded and consists of a frame, frame, roofs and an outer and inner skin.

Dimensions:

Body length 15 m.

Body width 2.6 m.

Height with lowered pantograph 3.6 m.

Wagon weight 20 tons

Body equipment.

Outdoor equipment.

A pantograph is installed on the roof, the radio reactor that reduces the radio interference in the houses and protects against the overvoltage of the contact network.

The outfolder is used to protect against lightning in the car. In the front of the body at the top of the air intake for ventilation, windshield tempered, polished without distortion and chips installed in aluminum profile. Further, the wiper, inter-avail electrical connection, the handle for wipers, headlights, turn signals, dimensions, substrates on the buffer beam and the plug of the additional and main instrument. Additional device carries out, and main to work in the connected system. Bottom under the car safety board.

On the bikes of the window bokam, installed in aluminum profile with valve typewards, the right rear-view mirror. On the right three valve doors suspended on two upper and two lower brackets. From the bottom of the falseboard with contact panels, side dimensions and turn signals, side route pointer.

Behind the body glass installed in aluminum profiles, interlessn electrical connection, dimensions, turn signals, stop signals and an additional coupling device fork.

Interior equipment (salon and cabin).

Salon. The steps and the floor are covered with rubber mats and fastened with metal straps. Wear rugs no more than 50%, the hatch covers should not perform more than 8 mm from the floor level. Vertical handrails are fixed near the doors, and on the ceiling horizontal handrails, they are all covered with insulation. Inside the cabin installed seats having a metal frame, crumpled by soft material. Under all seats, with the exception of two, heating elements (furnaces) are installed, and under the two sandboxes are under the two. The door has a door-drive, in the first two - on the right, and at the rear door - on the left. Also in the cabin there are two hammers for breaking a glass, near the door stop button on demand and emergency opening of doors and stop valves on the seals. Between the seats portable hitch. On the front wall, the rule of use by public transport. Three loudspeakers inside and one outside the cabin. In the ceiling in two rows, light bulbs are closed with platonys for lighting the cabin.

Cabin. Separated from the salon by partitions and fitting door. Inside the driver's seat, frown by natural material and adjustable in height. Control panel with measuring, signal instrument, tools and buttons.

On the floor pedal safety and sandbox pedal, on the left panel with high-voltage and low-voltage fuses. On the right control circuit separator, driver controller, two automaton (AV1, AB2). In the top of the glass, the route pointer, the sun protective visor, on the right rope of Pantograf, 106 panel and one fire extinguisher, and the second in the cabin is replaced with sandbox.

Heating of the cabin and cabins. It is carried out at the expense of furnaces installed under the seats, and in the new modifications tram due to climate control over the doors. The cab is heated by the oven under the driver's seat, the calorifer of the back and glass heating. In the cabin, the ventilation is natural at the expense of the vessels and doors.

Frame frame.

The frame is the bottom of the body consisting of two longitudinal and two transverse beams. Corses and two pivot beams in the center of which kkvornni are welded inside for stiffness and hidery of the equipment, and the body is installed on the trolleys and turns. The cross-beams are welded platform and ends with buffer beams. Contact panels are fastened to the frame, launchers and brake resistances are fixed in the middle.

Tram frame.

The frame is vertical racks that are welded along the entire length of the frame. For stiffness, connected by longitudinal beams and corners.

Roof tram.

Roof arcs that are welded to the opposite frame racks. For stiffness, connected by longitudinal beams and corners. The outer sheath consists of steel sheets with a thickness of 0.8 mm. The roof is made of fiberglass, internal lining from laminated chipboard. Between the trim insulation. The floor is filling from plywood, covered with rubber rugs for electric security. In the floor there are hatches closed with covers. They serve to inspect the tram equipment.

Trolleys.

Serve for movement, braking, tram turns and equipment hitch.

Cart device.

It consists of two wheeled steams, two longitudinal and two transverse beams and one pellery beam. The axis of the wheeled pairs is closed with a long and short casing, are connected by two longitudinal beams at the ends of which there are paws, through rubber gaskets fall on the casing and are fastened with covers with bolts and nuts. The brackets on which transverse beams are installed are welded to the longitudinal beams, on the one hand, they are connected through the springs, and on the other hand through rubber gaskets. Springs installed in the center, on which the pivot beam hangs on top, in the center of which there is a pivot hole through which the body is installed on the trolleys and turns the turn.

Two traction electric motors are installed on the transverse beams, each of them is connected to its wheeled pair cardan and gearbox.

Brake mechanisms.

1. When using the electro-dynamic brake, the engine switches in the generator mode.

2. Two drum brakes installed between cardan and gearbox, serving to stop and parking brakes.

The drum brake brake with a solenoid, which is attached to the longitudinal beam is turned off.

3. There are two rail brakes between whears, which serve for emergency stop.

On large covers there is grounding that provide the passage of electric current into the rails. Two suspended spring springs soften the shocks and blows, making a softer, the hole in the center of the longitudinal beam is necessary for turning.

Rotary device. It consists of a squaster, which is fastened on a pivotal beam of the body frame and a hole in a pellery beam of the trolley. To connect the body with trolleys, the knevinen starts in a pivot hole and a thick lubricant is laid for the ease of rotation and put gaskets. So that the lubricant does not flow through the squastle sells the rod, the lid dresses on the bottom and is fixed with the nut.

Operating principle. At the turn, the trolley moves in the direction of the rail and turns around the squastron, and since it is still fixed on the body frame continues to move directly, so the body takes place (1-1.2 m). At the turn, the driver must be particularly attentive. If he sees that it does not fit into turn due to dimensions, it should stop and submit a sound warning signal.

Spring hanging.

It is installed in the center of longitudinal beams and serve to mitigate the jackets and shocks, the oscillation deviations and the uniform distribution of the body weight and passengers between the wheels.

Hanging is assembled from eight rubber rings overlapped for stiffness alternately with steel rings, forming a hollow cylinder inside, which is built in a glass with two springs of different packing. Bottom under the glass rubber gasket. Top on the springs through the washer dressed a pellery beam. Sproughts are fixed in vertical and horizontal planes. The vertical plane is made by a hinge thrust that is attached to a pivot and longitudinal beam. For mounting in the longitudinal plane on the sides of the springs, the brackets are welded and rubber gaskets are applied.

Operating principle. When moving, as the scene is filmed, the springs are compressed, with the pivot beam lowered to rubber gaskets and with further increase in the load, they are closely compressed, the glass is lowered down and presses the rubber gasket. Such a load is considered to be maximum and unacceptable, because if a shot appears at the junction, it will go on a spring hanging, in which there is no element that could have redeemed this blow. Therefore, under the action of impact, the glass is thrown or can burst springs and rubber gaskets.

Reception of spring suspension. Approaching the car, we are visually convinced that the car is exactly not seven, there are no cracks on spring hanging and rings, it is checked on a vertical hinge thrust, and while driving the lack of side pitch, which occurs when the lateral shock absorbers.

PAIR OF WHEELS.

It serves to direct the movement of the tram along the rail canvas. It consists of the axis of the uneven section, the wheels are dressed, the bearing bearings are installed behind them.

Closer to the center of the dressed driven gear gear, and on both sides of her ball bearings. The axis rotates in the box and the ball bearings and are closed with a short and long casing, they are fastened with bolts and form the gearbox body.

On a large case there is a grounding device, and in a small case a leading gear gear. The most important thing is the observance of the sizes between wheels (1474 +/- 2), this size is obliged to monitor the locksmiths in

WHEEL.

It consists of a hub, wheel center, bandage, rubber pads, a pressure disk, 8 bolts with nuts, central (hub) nuts and 2 copper shunts.

The hub is painted at the end of the axis and connects with it for a single integer. The wheelbase with a bandage and a flabby is dressed on the hub ( flange - The protrusion that fastens the wheel to jump from the rail head).

Bandage from the inside is fixed by a locking ring, and with the outer there is a protrusion. On both sides of the wheel center, rubber gaskets are installed, outside closed by a pressure disk and all this is fastened with 8 bolts and nuts, the nuts are adjusted by locking plates.

The central (hub) nut huses on the hub and stops 2 plates. To pass the current there are 2 copper shunts that are attached to the band in one end, and the other to the pressure disk.

Bearings.

Serve for the support of the axis or shaft and reduce friction during rotation. It is divided into rolling bearings and sliding. Bearings Slide is ordinary sleeves and are used at low rotation speeds. Rolling bearings are used when the axes rotate with high speeds. It consists of two subsidiaries, between which balls or rollers are installed in the ring. There is two row roller tapered on the wheel pair.

The inner clip is pressed on the axis of the wheel pair and clamped on both sides of the sleeves are dressed on the axis. Outdoor with two rows of rollers is dressed on the inner clip, the clip is installed in a glass on one side of the glass rests on the protrusion on the housing, and on the other hand, which is fastened to the housing bolt. On both sides, oil-reflective rings are put, the lubricant of the bearing is supplied through the oil tape (tv suit) and the hole in the glass.

Operating principle.

Rotation from the engine through the drive shaft and the gearbox is transmitted to the axis of the wheel pair. It begins to rotate together with the inner bearing rope and with the help of rollers rolling through the outer clip, while the lubricant is sprayed, falls on the oil-reflective rings, and by returning back.

Cardan shaft.

It serves to transmit rotation from the engine shaft to the shaft of the gearbox. It consists of two flange forks, two cardan hinges, mobile and fixed forks. One flange plug is attached to the engine shaft, and the other to the shaft of the gearbox. In the forks there are holes for the installation of a cardan hinge. The fixed fork is made in the shape of a pipe with sliced \u200b\u200binside by slots.

The movable plug consists of a balancing pipe, on one side the shaft is welded with outer slots, and on the other hand, a fork with holes for a cardan hinge. The moving plug will start in a fixed, can move inside it, and the shaft length can increase or decrease.

The cardan hinge serves to connect flange forks with cardan shaft forks. It consists of crosses, four needle bearings and four covers. The cross is well sanded ends, two vertical end are inserted into the holes of the knives of the cardan shaft, and the two horizontal in the hole of the flange forks. On the ends of the crossbars are dressed needle bearings, which are closed with covers with two bolts and locking plates. For normal operation of the cardan shaft, the lubricant should be in needle bearings and a slotted connection. In the slotted connection, the lubricant is added via the mastelier, in the stationary fork, and so that it does not flow out, the cover with the felt gland turns onto the plug. In needle bearings, the lubricant falls through the hole inside the crosses and in the future it is periodically laid in these holes.

Operating principle.

Rotation from the engine is transmitted to all parts of the cardan shaft, in addition, the moving plug goes inside the stationary plug, and the flange plugs turn around the crossings ends.

Reducer.

It serves to transmit rotation from the engine, through the drive shaft on the wheeler pair, while the direction of rotation changes by 90 degrees.

Consists of two gears: one presenter, the other led. The presenter gets rotation from the engine, and driven through the engagement of the teeth from the lead.

Rotation are:

Cylindrical (shafts are located in parallel to each other).

Conical (trees are perpendicular to each other).

Worm (shafts cross in space).

The gearbox is on a wheel pair. On the tram of the brand KTM 5 - single-stage, conical gearbox. The leading gear is made in one whole with the shaft and rotates in three roller bearings, they are installed in the glass, one end of the glass is attached to a small casing, and the other is closed with a lid. Through the hole in the lid, the end of the shaft comes out and is condensed with the gland. At the end of the shaft, the flange is dressed, which is fixed with the hub nut and is popping. The flange creates the brake drum (BCT) and the flange fork of the cardan shaft.

The driven gear consists of a hub, pressing on the axis of a wheel pair, to it with the help of bolts, a toothed crown is attached, which forms with its teeth to engage with the lead gear.

All these parts are closed with two covers that form the gearbox housing. There is a bay and observation hole in it. Through the filling hole in the inside poured lubricant.

Operating principle.

Rotation from the engine, through the cardan shaft is transmitted to the flange of the leading gear. She begins to rotate and through the engagement of the teeth rotates the slave gear. Together with it, the axis of the wheel pair and the tram begins to move, while the lubricant is sprinkled, it falls on the ball and roller bearings, thereby one front is lubricated with the gearbox, and two distances need to be lubricated only through the masl.

Fault gear.

1. Losening lubrication with dripping.

2. The presence of extraneous noises in the reducer.

3. The bolts and nuts fastening the elements of the reactive device are unlocked and unfixed.

If the reduction of the gearbox occurred, the driver must try, by switching the reversing knob of the KV (forward and backward) to return the reducer to work. If it does not work, it informs the central dispatcher and follows its instructions.

Brakes.

Motion safety is ensured by rapidly acting brakes:

BCT device.

There are two holes in the lower bracket, through them the trading axes with brake pads and are fixed with nuts. From the inside of the pads are attached brake lining. In the upper part there are protrusions for which a discharging spring dresses.

In the hole in the upper bracket, the axis, at one end, dresses the lever and is fixed with the nut, the lever through the thrust is connected to the solenoid, and on the other end of the axis the cam dresses. On both sides of it, two pairs of levers are dressed on the axes - outdoor and inner. The outer roller rests on the cam, and the screw into the inner lever, which pulls on the pads through the protrusion.

BCT faults.

1. Weakening the fastening of the BCT details.

2. Singing the rotary axes.

3. Brake linings wear.

4. Wire of the expansion cam and rollers.

5. Reity of the solenoid thrust.

6. Malfunction of solenoid light bulbs.

7. Weakening or breakage of the brake spring.

Reception bkt.

Check when leaving the depot, on a "zero" flight, in a specially reserved place, usually one or the other side of the depot, to the first stop, at the pillar with a sign "Service braking". At the speed of 40 km / h, with clean and dry rails and an empty car. The main handle of KV is translated from the position "T 1" to "T 4" and the car should stop at a distance of 45 m, without reaching 5 m to the second pillar. Also check the "brake" and "diet" buttons. If the car has good brakes, then the driver will reach the stop and starts planting passengers. If the brakes are faulty, then informs the central dispatcher and its instructions follows.

Rail brake (RT).

It serves for emergency stop, in the threat of a departure or collision. On the car four rail brakes, two on each trolley.

Device RT.

It consists of a core and winding, closed with a metal casing - called the RT coil, and the ends of the winding are removed from the case in the form of terminals and connected to the battery. The core on both sides is closed with poles that are fastened with six bolts and nuts. Two of them are attached brackets for fastening to the trolley. A wooden bar is installed between the poles, the sides are closed with covers. Rail brake has a vertical and horizontal suspension.

The vertical suspension has two brackets dressed on two rail brake bolts and two brackets welded to spring suspension brackets. Through the holes, the upper and lower rods are fastened, which are bonded between themselves with a hinge bar. The lower rod is fastened with a nut, and the spring dresses the spring, which is welded to the bracket and is fixed in the upper part of the adjusting nut.

To while driving, independently of the RT shaking was strictly over the rail head, there is a horizontal suspension. A rod with springs and fork is attached to the bracket of the longitudinal beam, the ends of which are crankly attached to the RT. A bracket is welded to the longitudinal beam, which from the inside rests on the RT.

Principle of operation of the RT.

The RT is included on the position of the KV 5 position, upon vacation of the PB, disrupting the SC, when burning 7 and 8 of the fuse and click on the "Mentor" button on the control panel.

When turning on the current comes to the coil, it magnetizes the core and its poles. RT drops with a braking force of 5 tons each, the springs are compressed. When disabling, the magnetic field disappears and the RT is demaging, under the action of springs, rises and occupies its original position.

Malfunctions of the RT.

1. Mechanical:

There are cracks on the poles.

Non-naughty nuts bolts.

RT should not be selected due to the weakening of the springs.

There are cracks on the hinge bar.

2. Electrical:

MODER 1 and CRT 2 contactors are faulty.

Overcoiled PR 12 and PR 13.

Cutting conduction wires.

Reception of RT.

Approaching the car, the driver is convinced that the RT does not shivered, checks them on the absence of mechanical malfunctions, sign up the driver is convinced that the springs return the brake to its original position. Going to the cabin check the triggering of the Republic of Tatarstan, for this we put the main handle of the KV to the position "T 5" and through the inclusion of the contactor KRT 1, you can hear the fall of all RT, the arrow of the low-voltage ammeter rejected 100 and in the right. Then check the inclusion of the contactor KRT 2, through the PB vacation, the arrow of the low-voltage ammeter has deviated 100 and in the right. To make sure that all four RT fell, the driver leaves the main handle of the KV at the position "T 5", and the Bashmak puts on the PB and comes out of the car, looks at the RT on triggering. If one of the RT did not work, the driver checks the gap with a reversible handle, it should be 8 - 12 mm.

When depoted from the depot, at a post with a sign "Emergency braking", at a speed of 40 km / h, the driver removes his leg with PB and on dry and clean rails the brake path is unable to exceed 21 m. Also at all end stations, the driver conducts a visual inspection of the Republic of Tajikistan.

SANDBOX.

It serves to increase the clutch force of the wheels with rails, when braking, so that the car does not start to use or during a plaster and during acceleration, it did not stop. The sandboxes are installed inside the cabin, under two seats. One is on the right and raw down the sand under the first wheel pair, the first trolley. The second sandbox is on the left and sweeping sand under the first wheel pair, the second trolley.

Sandbox device.

Two sandboxes are installed in the boxes closed on the locks, under the seats inside the cabin. Inside the bunker with a volume of 17.5 kg of bulk, dry sand. Nearby is an electro-magnetic drive consisting of a coil and a movable core. Winding ends are connected to a low-voltage power source. The end of the core through a biscuit lever and thrust connects with the damper. It is installed on the axis attached to the bunker. The flap closes the bunker hole and presses against the wall using the spring. The second hole is in the floor, before the damper. The flange and sandy sleeve is mounted below, the end of the sleeve is above the rail head and is held using the bracket attached on the longitudinal beam of the trolley.

Operating principle.

The sandbox can work forcibly and automatically. Forcibly sandbox will only work from pressing the sandbox pedal (PP), which is located on the floor, in the tram cabin, on the right.

In case of emergency braking (sly or PB leave), the sandbox will turn on automatically. The current is fed to the coil. It creates a magnetic field that attracts the core, it turns the damper through the biscuit lever and pulls the damper, the holes open and the sand begins to pour.

When the coil is turned off, the magnetic field disappears, the core drops down and all parts are returned to its original state.

Fault.

1. Weakening the fastening of parts.

2. Mechanical core trip.

3. Open supply wires.

4. Short closure in the coil.

5. PP does not work.

6. Not included PC 1

7. Turned up PV 11.

Sandbox technique.

The driver must make sure that the sleeve is above the rail head. Going into the salon, checks the presence of dry and bulk sand in bunkers, lever system and turning the damper. Puts on PP shrik and coming out of the car, it is convinced that the sand flows. If it does not limp, then cleans the sandy sleeve. At the end stations, if he often used sand, then checks and adds from sandboxes that are at the station.

The sandbox is not effective when turning the tram, due to the removal of the body, the sleeve goes beyond the head of the rail. If at least one sandbox failed, the driver is obliged to inform the dispatcher and return to the depot.

COUPLER.

It happens the main and extra. Additional is used to tow a faulty car, and the main combines the trams among themselves, to work on the system.

An additional coupling device consists of two forks; The device itself is located in the cabin between the seats. The plug with a rod is done through buffer beams of the body, in front and rear. The rod dresses the spring and is fixed with a nut.

The portable coupling device consists of two pipes, at the ends of which there are tongues with holes. In the center, the pipes are connected by two rods, which makes the coupling tight. When towing, the driver first fastens the hitch to the fork of a working carriage, and then to a defective fork, it fits the rod from the clamp and spop.

The main coupling devices are divided into two types:

Auto.

Type "Handshake".

Handshake type coupling consists of a bracket with a fork that is attached to the body frame. There is also a clamp, a head rod, a fork with tongues and holes, handle for manual coupling. One end of the rod dresses the clamp with a hole inside, to mitigate the shocks and shock, dressed the shock absorber and fastened with a nut. It softens the blows caused by plane from the place and when tram braking.

The clamp of the main device is started in the plug of the bracket, the rod is used through the hole and fixes the nut. The hitch can be rotated around the rod. The other end of the coupling device falls on a buffer beam, which is welded from below to the body frame.

If the main coupling device is not used, then with the help of the bracket, it is attached to the fork of an additional instrument.

The automatic coupling device consists of a pipe, a round head is welded to it. On the other hand, the clamp is mounted on the pipe with a shock absorber. The round head on the sides there are two guides, between them a tongue with a hole and a bottom under the tongue groove for passing the fork of the second coupling device. In the forks there is a hole for the rod. The rod passes through the head and the spring is dressed on it. The position of the rod is regulated by a handle from above.

On the one hand, the housing knob is attached to the bracket fork, and the second point of attachment is the bracket welded to the body frame with spring, which is also attached to the body frame. The head screw is attached to the fork of an additional coupling device. When the coupling, the couppers must be fixed with brackets, which is located in the center of buffer beams. The handle must be lowered down and the rod must be visible in the groove.

With a coupling, a serviceable car moves to a faulty, while the tongues do not enter the grooves of the heads and will not be plugged with the help of rods.

Door-drive.

Three doors suspended on two top and two lower brackets. There are rollers in the brackets that are inserted into the tram guides on the body. Each door has its own drive: the first two it is installed in the cabin on the right, and they have a casing on the left and closed. The drive consists of an electrical and mechanical part.

The electrical chain includes low-voltage fuses (PV 6, 7, 8-25 A), a toggle switch (on PU), two ended switches that are fastened from outside the body, two on each door and triggered when the door is fully open or closed. On PU there are two light bulbs (opening and closing), the light bulb lights only if all three doors worked. The two contactors of the efficiency - 110 are also installed, which are located on the contact panel in the front of the body, on the left in the course of the movement, one connects the engine to the opening, and the other to the closure.

Engine shaft, through the coupling is connected to the mechanical part. It includes: a gearbox closed. One end of the shaft axis of the gearbox is removed and the stars are dressed on it - the main one, and the extra - stretch is attached. On the main stars of dressed chain, the ends of which are attached to the sidewalls of the door. Stretching stars adjusts the tension of the chain.

On the other hand, the axis dresses the friction, with which you can adjust the speed opening or closing the door. Also, the friction can turn off the motor shaft from the gearbox, if someone has squeezed the door or the roller cannot move along the guide.

Operating principle.

To open the door, the driver turns the toggle switch to the opening, while the electrical circuit is closed and the current comes from the plus terminal, through the fuse, through the toggle switch, through the contact switch to the contactor, which connects the engine and through the coupling, rotation is transmitted to the gearbox. The stars begins to rotate and moves the chain along with the door. When the door fully opens, the battle on the door hits the roller of the end switch, which turns off the engine and if all three doors open the light bulb on the PU, after which the toggle is returned to the neutral position.

To close the door, the toggle switch turns to the closure and the current goes as too, only through another end switch and another contactor. It causes the engine shaft to rotate in the other side and the door moves to the closure. When the door is completely closed, it hits the door on the door along the roller of the end switch, which turns off the engine and if all three doors closed the light bulb on the PU, after which the toggle is returned to the neutral position.

Also, the doors can be opened with the help of emergency switches that are located in the cabin above the door and sessured. Outside the rear door can be opened and close the toggle switch on the battery. On four-door wagons, the door-drive is located on top and to close the door manually need drive lever turn down.

Fault.

1. Turned up PV 6, 7, 8.

2. Focused a toggle switch.

3. Light bulb burned.

4. Does not work the end switch.

5. Contactor efficiency is not working - 110.

6. The electric motor failed.

7. The coupling occurred.

8. Fees lubricant from the gearbox, or it discerns the time of the year.

9. Weakened the fastening of the stars.

10. The integrity or fastening of the chain is broken.

If the door does not open and does not close, you need to close it manually, for this the driver rotates the clutch and the door begins to move, after which it will reach the final, if there is a locksmith, then makes an application for repairs and a locksmaker eliminates. If there is no locksmith, the driver itself changes the fuse, checks the rollers of the end switches, the triggering of the contactor, the state of the stars and chains. If the door and from rotation of the clutch does not move, since the reducer has jammed, then the driver reports the dispatcher, places passengers and follows the indications of the dispatcher. If a chain break occurred, the door is closed manually and fixed with a shoe or a lomika, as well as together

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Tram (from the English tram (car, trolley) and WAY (path), the name happened, one of the versions, from the car carriages for the transport of coal in the mines of the United Kingdom) is the type of street rail public transport for the transport of passengers on specified (fixed) routes, Usually on electric traction used mainly in cities.

Trams arose in the first half of the XIX century (originally on horseback), electric - at the end of the XIX century. After the heyday, the epoch of which fell for the period between world wars, the trams decline began, but somewhere since the 70s of the 20th century, there is a significant increase in the tram popularity, including environmental reasons.

Most trams use electricity with electricity supply through an air contact network using current receivers (pantographs or rods), but there are also trams with power from the contact third rail or battery.

In addition to electrical, there are equestrian (kinks), cable or cable and diesel trams. In the past there were pneumatic, steam and benzomotor trams.

There are also suburban, long-distance, sanitary, service and freight trams.

Terminology

In the context that does not require terminological clarity, the word "tram" may be called:

· Crew (train) tram,

· Separate car tram,

· Tram household or tram systems (eg, "Petersburg tram"),

· A combination of tram farms in the region or country (eg, "Russian tram").

Varieties trams

The usual tram speed is located from 45 to 70 km / h. The average speed of the message ranges from 10-12 to 30-35 km / h. In Russia, tram systems with an average operating speed of more than 24 km / h are referred to as "high-speed".

Characteristics of the "average" tram car operating in Russia 1 (high-polished motor four-axis 15-meter):

· Mass: 15-20 tons.

· Power: 4? 40-60 kW.

· Passenger capacity: 100-200 people.

· Maximum speed: 50-75 km / h.

Cargo trams

Cargo trams were widespread in the flourishing era of intercity trams, but they were used and continue to be used in cities. The cargo tram depot was in St. Petersburg, Moscow, Kharkov and other cities.

Specratravia

Cargo cars, rail carriers and museum wagon in Tula

To ensure sustainable work in tram farms, in addition to passenger cars, there are usually some special purpose wagons.

· Cargo cars

· Snapper wagons

· Traveling wagons (path laboratories)

· Railroad carriages

· Polywomen cars

· Contact network laboratories

· Wagons-rails

· Electrovoza for the needs of the tramway 2

· Cars-tractors

· Vacuum cleaner car 3

Trams, first of all, are associated with urban transport, but long-distance and suburban trams were also very common in the past.

In Europe, there was a network of long-distance trams of Belgium, known as the Netherl. Buurtspoorwegen (literally - "Local Railways") or Fr. Le Tram Vincial. "Society of local railways" was established on May 29, 1884 in order to build roads for steam trams where the construction of ordinary railways was disadvantageous. The first section of local railways (between Ostend and Nuvport, now is part of the coast tram line) was opened in July 1885.

In 1925, the total length of local railways was 5,200 kilometers. For comparison: now the overall length of the Belgian railway network is 3518 km, while Belgium has the highest density of railways in the world. After 1925, the length of local railways was constantly decreased, since long-distance trams were replaced by buses. The last lines of local railways were closed in the seventies. Until our days, only the coastline has been preserved.

Electrified was 1500 km of local railways. Steam trams were used for not electrified areas, they were primarily used for freight traffic, and diesel trams were used to transport passengers. Local railways had a 1000 mm stake.

Long-distance trams were also common in the Netherlands. As in Belgium, they were originally steam, but then the steam trams were replaced with electric and diesel. In the Netherlands, the era of long-distance trams ended on February 14, 1966.

Until 1936, from Vienna in Bratislava, it was possible to take a city tram.

Pretty old GT6 car on Oberrheinische Eisenbahn lines

To date, long-distance trams of the first generation have been preserved in Belgium (already mentioned by the coast tram), Austria (Wiener Lokalbahnen, a country line with a length of 30.4 km), Poland (the so-called Silesian Inerturbans, a system connecting thirteen cities with a center in Katowice), Germany (for example, Oberrheinische Eisenbahn, operating trams between the cities of Mannheim, Heidelberg and Weinheim).

On many local railway lines of Switzerland, cars are operated, more similar to trams than regular trains.

At the end of the XX century, country trams began to appear again. Often, closed lines of suburban railways were converted to the traffic of trams. Such is a manchester tram country lines.

In recent years, the extensive network of long-distance trams was created in the vicinity of the German city of Karlsruhe. Most of the lines of this tram are converted railway lines.

The new concept is a "tram train". In the city center, such trams are no different from ordinary, but outside the city they use the suburban lines of railways, while not railway lines are construed under the trams, but on the contrary. Therefore, such trams are equipped with a double power supply system (750 V DC for urban lines and 1500 or 3000 in direct current or 15,000 alternating current for railways) and the railway system of the automatic transmission. On the railway lines themselves, the movement of ordinary trains is thus maintained by trains and trams share infrastructure.

Now, according to the "Tram-Train" scheme, there are Country routes of Saarbruckensky tram and some parts of the system in Karlsruhe, as well as trams in Kassel, Nordhausen, Chemnitz, Zvikau and some other cities.

Outside of Germany, the "Tram-Train" system is common. An interesting example is the Swiss city of Neuchatel 4. This city has and develops urban and suburban trams that demonstrate their benefits, despite the extremely small size of the city - its population is only 32 thousand inhabitants. The creation of a system of long-distance trams similar to German is now being conducted in the Netherlands.

In our country, the Orangel 40-kilometer tram line was built on the eve of 1917, part of which was preserved and used for route No. 36. There are projects of recreation of a suburban line to Peterhof. From 1949 to 1976, the Chelyabinsk line operated - Kopeisk.

International trams

Some tram lines crosses not only administrative, but also government borders. As of 2007, a tram can get from Germany (Saarbrucken) to France along the Saarbahn tram line. The territory of the neighboring France comes route No. 10 of the Basel tram 5 6 (Switzerland).

It is possible that in the future international trams in Europe will become more. In 2006, plans for the extension of the lines 3 and 11 of the Basel tram tram to St. Station were made public. Louis in France by 2012--2014. There are also extension plans 8 to WEIL Am Rhein Station in Germany. If these plans are implemented, then one tram network will unite three states 7.

In 2013, it is planned to revive the regular tram line between Vienna and Bratislava, which existed in 1914-1945 and closed due to damage resulting from the fighting 8.

Specialized trams

Hotel Tram Riffelalp

In the past, tram lines were distributed, which were built specifically for servicing individual infrastructure facilities. Usually such lines associated this object (for example, a hotel, hospital) with a railway station. Some examples:

· At the beginning of the 20th century, His own tram line had a Cenden Bay Hotel (Cruden Bay, Aberdeenshire, Scotland) 9

· Your own tram line had a Duin En Bosch Hospital in Bakkum (Netherlands). The line went from the railway station in the neighboring village by the coastrock to the hospital. At first there was an equestrian thrust on the line, but in 1920 the tram was electrified (the only car was converted out of the old car of Amsterdam). In 1938, the line was closed and replaced by bus. 10

· In 1911, the Netherlands Aviation Netherlands Tram Society was built. This line connected the station denander and the Satsberg airfield. eleven

· One of the few hotel tram lines existing now - Tram Riffelalp in Switzerland. This line operated from 1899 to 1960. In 2001, it was restored in a state close to the original.

· In 1989, his own tram line opened the Bustoan Pension, located in the village of Dairy (Crimea, next to Evpatoria).

· Line tram Caves An Ana was built specifically for the delivery of tourists to the entrance to the cave.

Water tram

Under water (river), tram in Russia usually understand the river passenger transport within the city (see River Tram). However, in England in the XIX century, a tram was built, which went along the rails laid along the coast on the seabed (see Daddy Long Legs).

Advantages and disadvantages

The comparative effectiveness of the tram, as well as other types of transport, is determined not only by its technologically determined advantages and disadvantages, but also the general level of public transport in a particular country, attitude towards him of municipal authorities and residents, features of the planning structure of cities. The characteristics referred to below are technologically determined and cannot be the versatile criteria for "for" or "against" the tram in various cities and countries.

Benefits

· The initial costs (when creating a tram system) are lower than the costs necessary for the construction of the subway or the monorail system, since there is no need to complete the lines (although the line can be held in the tunnels in the tunnels and the lines, there is no need to arrange them On all over the route). However, the construction of a terrestrial tram is usually associated with the reorganization of streets and intersections, which increases the price and leads to a deterioration in the road situation during construction.

· With a fairly large passenger traffic, the tram is significantly cheaper than the service of the bus and the trolley buses source is not specified 163 days.

· Catering wagons are usually higher than buses and trolley buses.

· Trams, like other electric transport, do not contaminate air combustion products (although the power plants producing currents can pollute the environment).

· The only appearance of ground urban transport, which can be variable length due to the clutch of cars in the train per hour of peak and disclaimed the rest of the time (in the metro station, the main factor is the length of the platform).

· Potentially low minimum interval (in an isolated system), for example, in the rog curve, it is even 40 seconds at three cars, compared with the limit at 1:20 on the subway.

· Ways are visible, therefore, potential passengers are guessed about tracing.

· Can use railway infrastructure, and in world practice both at the same time (in small towns) and former (as a line on fit).

· You can inform passengers about the route of the arriving tram before another street type of transport (route lights).

· Unlike trolleybuses, the tram is quite electrically saved for passengers when landing and disembarking, since its body is always ground through wheels and rails.

· Tram ensure a beneficial self-ability than a bus or trolleybus. The optimal loading of the bus or trolleybus line is not over 3-4 thousand passengers per hour 12, the "classic" tram is up to 7 thousand passengers per hour, but under certain conditions - and more than 13.

· Although the tram car is much more expensive than the bus and trolley buses, trams are characterized by a beneficial service life. If the bus rarely serves longer than ten years, then the tram can be operated for 30-40 years. So, in Belgium, along with modern low-voltage, successfully operated PCC trams issued in 1971--1974. More than 200 trams of Konstal 13n release of 1959-1969 drives around Warsaw. Milan is currently operating 163 trams of the 1500 series, issued in 1928-1935.

· World practice has shown that motorists are actively transplanted only on rail transport. The introduction of high-speed bus / trolleybus systems gave 5% of the flow from personal transport to public transport.

disadvantages

"Caution, tram rails!" - Road sign for cyclists.

· The tram line in the construction is much more expensive than trolleybus and even more so bus.

· The transport ability of trams is lower than that of the subway: usually no more than 15,000 passengers per hour at the tram, and up to 80,000 passengers per hour in each direction at the Soviet type metro station (only in Moscow and St. Petersburg) 14.

· Tram rails are dangerous for cyclists and motorcyclists trying to cross them under an acute angle.

· Incorrectly parked car or traffic accident in dimensions can stop moving on a large portion of the tram line. In the event of a breakdown, its tram, as a rule, pushes into a depot or on the backup path following it, that, as a result, leads to a one of the rolling stock two units at once. In some cities there are no practice as quickly as possible freedation of the tramways during accidents and breakdowns, which often leads to long stops of movement.

· The tram network is distinguished by relatively low flexibility (which can be compensated by network branching). On the contrary, the bus network is very easy to change if necessary (for example, in the case of the repair of the street), and the trolleybus network becomes very flexible when using deobeus.

· Tram household requires at least inexpensive, but regular maintenance. Unsatisfactory maintenance leads to a deterioration of the status of rolling stock, discomfort for passengers, reduced speeds. Restoration of the launched farm costs very expensive (often easier and cheaper to build a new tram industry).

· Laying of tram lines in the city feature requires a skillful placement of paths and complicates the organization of movement. With a bad design, the removal of valuable urban land under the tram movement may be ineffective.

· In case of unsatisfactory content of the path, the likelihood of a tram with rail occurs that this situation makes the tram potentially more dangerous participant in the road.

· Tillage vibration caused by tram can create acoustic discomfort for residents of the nearest buildings and lead to damage to their foundations. To reduce the vibration, it is necessary to regularly maintain the path (grinding to eliminate wave-like wear) and rolling stock (hollow pairs). When applying advanced technologies for laying, vibration paths can be minimized (often not at all).

· With a bad content of the path, the reverse traction current may go to the ground that arise "wandering currents" reinforce the corrosion of nearby underground metal structures (cable shells, sewage pipes and water pipes, assembly of buildings).

History

In the XIX century, as a result of the growth of cities and industrial enterprises, removal of housing from the locations of the application of labor, the growth of the mobility of urban residents faced the problem of the city transportation. The emerging Omnibuses began to be eased by street railways on horseback taiga. The first horse in the world opened in Baltimore (USA, Maryland) in 1828. There were attempts to bring railways on the streets on the streets on steam rod, but the experience was generally unsuccessful and did not get distribution. Since the use of horses was associated with a lot of inconvenience, attempts to introduce any type of mechanical traction on the tram are not stopped. In the US, there was a very popular cable rod, preserved to the present day in San Francisco as an attractions.

Achievements of physics in the field of electricity, the development of electrical engineering and inventive activities F. A. Pyrootsky in St. Petersburg and V. Von Siemens in Berlin led to the creation of the first passenger electric tram line between Berlin and Lighterfeld in 1881, built by the electrical enterprise Siemens. In 1885, as a result of the work of the American inventor L. Dafete, regardless of the works of Siemens and the Pyrozza, the electric tram appeared in the United States.

The electric tram turned out to be a profitable business, its rapid spread of the world began. He contributed to the creation of practical currents of the current (rod current of the spray and the bougiel current of Siemens).

In 1892, Kiev acquired the first in the Russian Empire of the electric tram, and other Russian cities soon followed the example of Kiev: the tram appeared in Nizhny Novgorod in 1896, in Ekaterinoslava (now Dnepropetrovsk, Ukraine) in 1897, in Vitebsk, Kursk and Orel in 1898, in Kremenchug, Moscow, Kazan, Zhytomyr in 1899, Yaroslavl in 1900, and in Odessa and in St. Petersburg - in 1907 (except for the tram worked in winter on the ice of the Neva since 1894) .

Up until the First World War, the electric tram is growing rapidly, hung out from the cities of competitors and few remaining Omnibuses. Along with electric tram in some cases, pneumatic, petrol and diesel were used. Trams were used on local suburban or long-distance lines. Often, urban railways were used for the delivery of goods (including in the wagons served directly from the railway).

After a pause caused by war and political change in Europe, the tram continued development, but less than a high rate. Now he has strong competitors - a car and, in particular, the bus. Cars have become more and more voluntary and affordable, and buses are ever more speed and comfortable, as well as economical due to the use of diesel engine. In the same period of time there appeared trolleybus. In the increased street movement, a classic tram on one side began to interfere with vehicles, and on the other - and he himself created a significant inconvenience. The income of tram companies began to fall. In response in 1929, the presidents of tram companies held a conference on which the decision was made to produce a series of unified, significantly improved cars that received PCC name. These cars, first saw the light in 1934, established a new bar in technical equipment, convenience and appearance tram, having an impact on the entire history of the tram for many years ahead.

Despite such progress of the American tram, in many developed countries there was a closure on the tram as a backward, uncomfortable type of transport, which does not affect the modern city. The folding of tram systems began. In Paris, the last line of the city tram was closed in 1937. In London, the tram existed until 1952, the reason for the delay in its liquidation was the war. Liquidation and contractions were tram networks and in many major cities in the world. Often the tram was replaced by trolleybus, however, the trolleybus lines in many places were also closed soon, not withstanding competition with other roads.

In the prewaging USSR, the closure on the tram is also established as backward transport, but the inaccessibility of cars for ordinary citizens did a tram more competitive with a relatively weak street stream. In addition, even in Moscow, the first metro lines opened only in 1935, and its network was still small and uneven on the city's area, the production of buses and trolley buses was also relatively small, therefore, before the 1950s, there was practically no alternative to passenger traffic. Where the tram was removed from the central streets and prospectuses, his lines were necessarily transferred to the neighboring parallel less lively streets and alley. Before the 1960s, the transportation of goods on the tram lines remained significant, but they played a particularly large role during the Great Patriotic War in a deposited Moscow and Blocade Leningrad.

After World War II, the process of eliminating the tram in many countries continued. Many lines damaged by war have not been restored. On the lines that have been modified by their resource, the path and wagons were poorly contained, were not modernized, which, against the background of the growing technical level of road transport, contributed to the formation of a negative image of the tram.

However, the tram relatively well continued to feel in Germany, Belgium, the Netherlands, Switzerland and the countries of the Soviet bloc. In the first three countries, a large distribution of a mixed type system was obtained, combining tram and metro (metro metro metro, premetro metro station, etc.). However, these countries did not cost without closing lines and even entire networks.

Already in the 70s of the 20th century, an understanding of the fact that mass motorization brings problems - was able, congestion, noise, a lack of space. The extensive path of solving these problems demanded large capitals and had a small return. Gradually, transport policy began to be reviewed in favor of public transport.

By that time, there were already new solutions in the field of the organization of tram traffic and technical solutions that the tram made a completely competitive type of transport. Began the revival tram. New tram systems were opened in Canada - in Toronto, Edmonton (1978) and Calgary (1981). By the 1990s, the process of the revival of the tram in the world scored full force. The tram systems of Paris and London, as well as other the most developed cities in the world reopened.

Against this background in Russia, the traditional (street) tram is still de facto being considered as an outdated type of transport, and in a number of cities, a significant part of the systems stagnates or in general collapses. Some tram households (in the cities of Arkhangelsk, Astrakhan, Voronezh, Ivanovo, Karpinsk, Grozny) ceased to exist. However, for example, in Volgograd, the so-called high-speed tram plays a large role (tram lines laid underground), in addition, it is in industrial areas of old Oskol and in Ust-Ilimsk, and a traditional tram develops consistently in Magnitogorsk.

In Ufa, Yaroslavl and in Kharkov, in recent years, there is a destruction of tramways, one of the depot in the capital of Bashkortostan is fully demolished, and two tram depots are closed in Kharkov. More than 50% of the paths were dismantled in Yaroslavl, more than 70% of rolling stock were written off, one tram depot was closed. The source is not specified 22 days

In recent years, the system of traditional tram and in Moscow continued to decline, but in April 2007, the metropolitan authorities officially announced the creation plans in the next 20 years of the high-speed tram system from 12 isolated from the street stream of the total production length of 220 km, which should be expanded in almost all Counties of the city. fifteen

The high-speed tram is valid in Kiev, connecting the southwest and the city center. In Krivoy Rog (Ukraine, Dnepropetrovsk region), the high-speed tram complements the system of the usual ground tram and unites 18 km in its farm, of which 6.9 km in the tunnels and 11 stations with modern infrastructure. On two routes, 17 compositions of 36 wagons operate daily.

Infrastructure. Depot

Storage, repair and maintenance of rolling stock are made in tram depot (tram parks). The lamps also dine in the depot. Small tram depots do not have a rings for turnover, and consist of one (or more) deadlocks that have access to the line. Large depot consist of a large ring, a variety of end-to-end paths (on which cars are defended in columns of several pieces in line), covered repair shops and trips on line. The depot is trying to post close to the final many routes (to reduce "zero flights"). If it is impossible (for example, the depot is on the line), then trams are followed by shortened flights, which in many cases, increases the intervals between "full" routes (for example, in Novokuznetsk, Depot No. 3 is on the line, and routes 2,6,8 , 9 follow in the depot of shortened flights and from the city and from Baydaevka). If there are no spare paths on the finite, then the wagons go to the depot and for lunch.

Points of maintenance

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In terms of tram systems, it is used in the final stops to ensure the repair and inspection of wagons, maintenance facilities are used. As a rule, PTO is located between the paths of the ditch to inspect and repair the ventilation equipment, small recesses on the sides of the rails for inspecting wheel carts, as well as stairs to examine a pantograph. Such systems in Russia exist, in particular, in Tula (invalid) and in St. Petersburg in Rostov-on-Don, Novocherkassk.

Passenger infrastructure

Landing and disembarking passengers is made on tram stops. The stop device depends on the method of placing the web. Stops on their own or separate canvase, as a rule, are supplied with powerful passenger platforms under the tram footage, equipped with pedestrian transitions through tram paths.

Stops on the combined canvase can also be equipped with raised over the carriageway and, possibly, fenced areas - reefuza. In Russia, refuments are rarely applied, most often the stops do not physically stand out, the passengers are waiting for the tram on the sidewalk and at the entrance / outlet of the tram cross the roadway (drivers of firewood vehicles are obliged to miss them in this case).

Stops are indicated by a sign with tram route numbers, sometimes with the schedule of motion or an indication of the intervals, often they are also equipped with a pavilion for waiting and benches.

A separate case is the sections of the tram lines deployed under the ground. In such areas, underground stations arranged similar to the metro stations.

In the past, some stops (first of all - on long-distance and suburban lines) had small station buildings similar to Rail. By analogy, such stops were also called tram stations.

Special place is occupied by tram-pedestrian streets, common in the centers of European cities. On this type of streets, the movement is allowed only for trams, cyclists and pedestrians. This type of device of the path contributes to increasing the transport accessibility of centers of cities, without applying ecology damage and without expanding transport spaces.

Organization of movement

Tram travel in Evpatoria (single-section system). Basically, the tram movement is laid down two oncoming paths, but there are also uninterrupted areas (for example, in Yekaterinburg, the line on the green island has a one-section portion with one runway) and even whole single-on-road systems with connectors (for example, in Noginsk, Evpatoria, Konotop, Antalya) Or without connectors (in Volchansk, mushrooms).

The final reversal points of the tram lines are both in the form of a ring (the most common option) and in the form of a triangle (when the car is moving back). In some cities, for example, bilateral trams are used in Budapest, capable of changing the direction of the following point, including in the impasses of the lines where the train turnover is made to cross the congress between the paths. The advantage of this method is that there is no need to build a reversal ring, which occupies a large area, and also that the final stop can be organized anywhere - this can be used when closing part of the path, if necessary (for example, in the event of some construction, requiring the closure of the road).

Frequently the end items of the lines tram, made in the form of a ring, have several ways, which makes it possible to overtake trains of different routes (for departure on a schedule), sucks a part of the wagons in the daytime trap period, storage of backup trains (for cases of failures in motion and substitution) , Sustainable trains before evacuation in the depot, sucks during dinner brigades. Such paths can be through or deadlock. The final, having a way development, the dispatching point and a dining room for counselors and conductors, in Russia are called tram stations.

Travel economy

Northern tram bridge in Voronezh. It is a two-story three-tier design. On the upper tier went to clarify the trams, and the two lower tiers - the right and left - serve to drive cars. The length of the bridge is 1.8 km, designed specifically for starting in the Voronezh high-speed tram

The device and placement of the path on the tram are carried out on the basis of compatibility requirements with the street, with hiking and automotive movement, high adverse ability and message speed, efficiency in the construction and operation. These requirements, generally speaking, conflict with each other, therefore, in each case, a compromise solution is selected corresponding to local conditions.

Placing a path

There are several basic accommodation options for tram canvas:

· Ownblights: The tram line passes separately from the road, for example, in the forest, field, separate bridge or overpass, separate tunnel.

· Outlookedblights: The tram canvas passes along the road, but apart from the roadway.

· Combinedblights: The canvas is not separated from the roadway and can be used by straight vehicles. Sometimes a canvas that is physically combined, considered separately if the entry of transport is prohibited from the administrative order. Most often, the combined canvas is located in the center of the street, but sometimes placed on the edges, at the sidewalks.

Device path

In different cities, trams use different width of the ruts, most often - the same as the usual railways (in Russia - 1520 mm, in Western Europe - 1435 mm). Unusual for their countries tramways in Rostov-on-Don - 1435 mm, in Dresden - 1450 mm, in Leipzig - 1458 mm. The narrow-chain tram lines are 1000 mm (for example, Kaliningrad, Pyatigorsk) and 1067 mm (in Tallinn).

For a tram in different conditions, both ordinary rails of electrically railway type and special tram (grooved), with a french and a sponge, allowing drowning rails in the pavement. In Russia, tram rails are made of softer steel so that the curves of the miminable radius can be made than on the railway.

Since the occurrence of tram and to this day, the tram uses the classic path of laying the path, similar to the laying path on the electric railway. The minimum technical requirements for the device and the content of the path are less strict than on the railway. This is caused by a smaller mass of trains and the load on the axis. Usually wooden sleepers are used to lay a tramway. To reduce noise, the rails on the joints are often welded electrically. There are also modern ways of the path of the path, allowing to reduce noise and vibration, eliminate the destructive effect on the adjacent part of the bridge, but their cost is significantly higher.

There is a problem of wave-like longitudinal wear of tram rails, the causes of which are uniquely not installed. With a strong wave-like wear, moving along the way the car is very shaking, it produces a roar, it is uncomfortable in it. The development of wave-like wear is supplanted by regular grinding rails. Unfortunately, in many tram farms of Russia, this procedure is not performed. So, in St. Petersburg, the rails-lifted cars do not go on line for several years.

Crossing and arrows

The arrows on the tram are usually simpler than rail, and in less stringent technical standards. They are not always equipped with a locking device and often have only one feather ("Sleep").

The arrows passing by tram "on wool" are usually not managed: the tram transfers the pen, rolling on it with the wheel. Arrows installed on the connectors and in reversal triangles, usually spring: the feather is pressed by the spring so that the tram coming from a single-section portion leaving the right (with right-hand traffic) pathway path; Tram traveling from the road, presses the pen with the wheel.

Arrows passing by tram "against wool" require control. Initially, the arrows were managed manually: on lines with low load - counselor, on tense - special work-arrochetons. At some intersections, central shooting posts were created, where the transition of all the arrows a crossroads could deal with one operator using mechanical load or electrical circuits. On the modern Russian tram, automatic electric shock arrows are dominated. The normal position of such an arrow usually corresponds to the turn right. On the contact suspension on the approach to the arrow, the so-called serial contact is installed (Lira, Salazki Zaga). When the chain is closed, the "Solenoid - contact - the engine - rail" turned on the engine (or special shunt) the solenoid translates the arrow to turn left; When the contact pass is not closed and the arrow remains in a normal position. After passing the arrows along the left branch, the tram currently closes the shunt installed on the contact suspension, and the solenoid translates the arrow to normal.

The passage of the arrows or crossmen by tram requires a noticeable reduction in speed, up to 1 km / h (regulated by the rules of tram farms). Currently, radio-controlled arrows and other designs of arrows, not superimposing restrictions on the movement mode at the entrance to the arrow, are becoming increasingly distribution. sixteen

Where the alternate movement of trams is arranged to overcome narrows at a short distance (for example, when driving around the narrow and short bridge, under an arch or overpass, on the site of narrowing the street of the historic center of the city), instead of the arrows, we can apply the plexus paths. In addition, sometimes the plexus of the paths arrange at the entrance to the intersections, where several directions are diverted: the anti-coherent arrow is installed "in advance", on the road from the nearest stop, where the speed of movement is low in itself, and thus you can avoid a special reduction in speed when passing Arrows at the intersection itself.

Gaytes

Gates (from English Gate: Gate) - the place of connecting the tram and railway networks (the term "Gate" is not official, but is used very widely). Gates are used mainly in order to unload the tram tracks on the tram platforms to the tram (at the same time, railway rails are directly moving into tram). For the permutation of cars from platforms on rails, lifting cranes and various options for jack posts are used. We note that unloading tram wagons from railway and car platforms can also use unloading overpass - deadlocks, on which the tram path is raised relative to the railway track (or road surface) on the loading height of the platform (while the rails on the platform are combined with tram rails on the overpass , and the car with its own way or in a tug goes from the platform).

In the "Tram Train" systems (see below) Gates are used to exit trams on the railway network. In some tram farms, it is possible to exit the railway cars to the tram network, for example, during the time of the USSR in Kharkov, the entire compounds were transported to the confectionery factory located near the Gaya.

In Kiev, before the construction of his own gate, the Metropolitan was used by tram-railway gate and tramways for driving metering in the Dnipro depot.

Power supply

In the early period of the development of electric tram, the electric networks of general use have not yet had enough development, so almost every new tramway has included its own central power plant. Now tram farms receive electricity from general-purpose electrical networks. Since the tram is powered by a constant current of a relatively low voltage, transmitting it over long distances is too expensive. Therefore, travelery substations are located along the lines, which are obtained from the networks alternating current of high voltage and convert it to a constant current, suitable for feeding to the contact network.

The rated voltage at the yield of the traction substation - 600 V, the rated voltage on the transmission of the rolling stock is 550 V. In some cities of the world, the voltage is 825 V (in the territory of the countries of the former USSR, such tension was used only for metro wagons).

In cities where the tram coexists with trolleybus, these types of transport, as a rule, have a common power plant.

Air Contact Network

The tram feeds on a constant electrical current through the roof of the current receiver located on the roof - usually it is a pantograph, but some farms are used and rods ("arcs") and rods or half-pengnes. Historically, the bougiels met in Europe more often, and in North America and Australia - the rods (for the reasons, see the "History" section). The suspension of the contact wire on the tram is usually arranged easier than on the railway.

When using the rod, a device of air arrows like trolleybus is required. In some cities, which uses a rod current (for example, San Francisco), on the sections of the tram and trolleybus lines of the tram and trolleybus lines, one of the contact wires is used simultaneously and tram, and trolleybus.

There are special designs for intersection of the air contact network tram and trolleybus. The crossing of tram lines with electrified railways is not allowed due to different voltages and the height of the suspension of contact networks.

Typically, rail chains are used to remove the reverse traction current. In case of poor condition of the path, the reverse traction current goes through the ground. ("Wandering currents" accelerate corrosion of metal underground designs of water supply and sewerage, telephone networks, fittings for buildings, metal and reinforced bridge designs.)

To overcome this shortage in some cities (for example, in Havana), a current system was used with two rods (as on trolleybus) (actually it turns the tram in the rail trolleybus).

Contact rails

On the very first trams, the third, contact rail was used, but it was soon abandoned: in the rain, short circuits often occurred. The contact between the third rail and the slider-current is broken due to fallen leaves and other dirt. Finally, such a system was unsafe at voltage above 100--150 V (it turned out very soon that such tension was insufficient).

Sometimes, primarily from aesthetic considerations, an improved version of the system with contact rails was used. In such a system, two contact rails (ordinary rails were no longer used as part of the electrical network) were located in a special flavor between the running rails, which excluded the danger of the electric shock for pedestrians (thus the tram is already obtained by the "rail trolleybus" with the lower current). In the US, contact rails were located at a depth of 45 cm from the street level and 30 cm from each other. Systems with in-depth contact rails existed in Washington, London, New York (only in Manhattan) and Paris. However, due to the high cost of laying contact rails in all cities, with the exception of Washington and Paris, a hybrid current system was applied - a third rail was used in the city center, and beyond the contact network.

Although the classic systems with power supply from the contact rail (pairs of contact rails) have not been preserved anywhere, to similar systems and are now being interested. So, in the construction of a tram in Bordeaux (opened in 2003), a modern, secure version of the system was created. In the historic center of the city, the tram receives electricity from the third rail located at the street level. The third rail is divided into eight meter sections, isolated from each other. Thanks to the electronics, only the selection of the third rail is located on which the tram is currently driving. However, during the operation, this system has many drawbacks, primarily associated with the action of rainwater. In connection with these problems at one of the sections in a kilometer long, the third rail was replaced with a contact network (the total length of the Bordeaux tram network is 21.3 km, of which 12 km with the third rail). In addition, the system turned out to be very expensive. The construction of a kilometer of the tram line with a third rail is about three times more expensive than a kilometer with a conventional air contact line.

Tramway construction

The tram is a self-propelled railway station, adapted for urban conditions (for example, steep turns, small dimensions, etc.). The tram can follow both the highlighted strip of movement and paths laid on the streets. Therefore, trams are equipped with signaling signals, brake lights and other means of alarm, characteristic of road transport.

The body of modern tram wagons is, as a rule, a all-metal design, and consists of a frame, frame, roof, external and internal trim, floor, doors. In terms of body, it usually has a form-made form, which provides free passage by the carriage wagon. Body elements are combined with a welding, clap, as well as screw and glue. 17:16. In the trams of early structures, wood was widely used, both in the elements of the frame and in the decoration elements. Recently, plastic is widely used in the decoration.

Most tram wagons currently has two-axis swivel carts, the use of which is due to the need for smooth fitting of the car to curves and ensure a quiet move in direct areas at considerable speeds of movement. The turn of the carts is carried out using a Friday installed on the pivot beams of the body and trolley. According to the construction of the carrier part of the carts are divided into frame and bridge; Currently applied mainly the second. The distance between the axes of the wheels in the trolley (the base of the cart) is usually 1900--1940 mm. 17:39.

The wheels perceive and transmit the load from the weight of the car and passengers, when moving, contact with rails, guide the movement of the car. Each wheel pair consists of an axis and two wheels pressed on it. According to the design of the wheel center, wheel pairs with rigid and cropped wheels are distinguished; Passenger cars in order to reduce noise when moving are equipped with wheel pairs with cripped wheels. 17:44.

Electrical equipment

Tram engines - most often DC traction engines. Recently, electronics appeared, which allows you to convert a constant current to which the tram feeds, to a variable, which allows the use of AC motors 18. From DC motors, they are advantageous from the fact that they practically do not require technical care and repair (alternating current asynchronous motors do not have high brushes, as well as other driving parts).

To transfer the torque from the traction electric motor to the axis of the wheel pair on the tram wagons, a cardan-gear transmission (mechanical gearbox and drive shaft) is used. 17:51

Engine management system

The current control device through the TED is called the control system. Management systems (SU) are divided into the following types:

· In the simplest case, the current adjustment through the engine is carried out using powerful resistances that are connected in series with a discrete engine. Such a control system is three types:

o The direct control system (NSR) is historically the first type of SU in trams. The driver by means of the lever connected with the contacts directly commutes the resistance in the electrical circuits of the rotor and the windings of TD.

o. Indirectnautomatic Painting Contactor Management System - In this system, the driver using the pedal or the controller lever carried out the switching of low-voltage electrical signals, which were controlled by high-voltage contactors.

o. Indirectautomatic RKSU - in it the closure and opening of contactors is controlled by a special servomotor. The dynamics of acceleration and braking is determined by a predetermined temporary sequence in the design of the RKSU. The power circuit switching unit assembled with the intermediary device is otherwise called the controller.

· Thyristorno-pulsed control system (TISA) - SU based on high-current thyristors, in which the current current is created not by switching resistance in the engine circuit, and by forming the time sequence of current pulses of a given frequency and duty. By changing these parameters, you can change the average current flowing through the TED, and consequently and control its torque. The advantage over the RCSU is a larger efficiency, since it is reduced to a minimum of thermal losses in the starting resistances of the power chain, but the braking of this SU ensures, as a rule, only electrodynamic.

· Electronic control system (transistor Su) asynchronous TED. One of the most economical electricity consumption and modern solutions, but rather expensive and in some cases is quite capricious (eg, unstable to external influences). Active application in such systems of control programmable microcontrollers creates a risk of exposure to program errors to the functioning of the entire system as a whole.

· On the tram wagons, piston-type compressors are usually installed. 17: 105 From compressed air can be activated by doors, brakes and some other auxiliary mechanisms. Since the tram is always provided with electricity in a sufficiently large quantity, it is also possible to refuse pneumatic drives with a replacement for electrical. This allows you to simplify the maintenance of the tram, but the cost of the carriage itself increases. According to such a scheme, all CHEF production cars are assembled, starting with KTM-5, Tatra T3 and more modern tatras, all PTMZ wagons starting with LM-99KE, all cars produced by Uraltransmash.

Evolution Layout Tram

The trams of the first generation (until the 1930s) usually had only two axes. At the very first trams (Lights of the XIX - XX centuries) were open sites in front and rear (sometimes called "balconies") such a layout was inherited from the wagon of the kink and was an example of inertia of thinking - if the front side of the kink was supposed to be open (to Kucher could manage horses), the open areas on the tram were an anachronism. Most of the two-cakes of this period had a wooden housing (although the frame of the tram, naturally, was metallic), and yet the metal was increasingly used to the twentieth years. The era of two-cakes was mainly over after World War II, although in some cities of the world such trams can be seen and understood (for example, in Lisbon).

Trams with biaxial trolleys and articulated trams

In the 1920s and 1930s, a new tram type came to replace the two-axle tram with two-axis trolleys. The tram relied on two trolleys, each of which had two axes. Since the end of the twentieth years, trams began to build mainly all-metal, and after World War II, the production of wooden trams was discontinued at all. In addition to single trams, articulated trams appeared (trams with "harmonica"). Trams on trolleys, both single and articulated, still remain the most common types of trams. See also PCC

Low full trams

By the third generation of trams include the so-called low-voltage trams. As follows from the name, their distinctive feature is the small height of the floor. To achieve this goal, all electrical equipment is made on the roof of the tram (on the "classic" trams, electrical equipment can be located under the floor). The advantages of a low-profile tram are convenience for disabled people, elderly, passengers with children's strollers, a faster landing and disembarkation.

Different designs trams. Black circles indicate the drive wheels (with a motor), white - nonferrous.

Low full trams are usually articulated, since the wheeled arches strongly limit the space for the axes turning, and this leads to the need to "recruit" the car from short support and slightly longer attachments. Hermelijn trams used in Belgium, for example, consist of five sections connected by "accordions". However, the floor is low at all throughout such a tram: over trolleys have to make an increase in gender. In the most progressive structures of trams (for example, Variotra trams working in Helsinki) solve this problem by refusing the carts and wheeled steam at all.

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History tram as a type of public transport. Appearance tram in terms of design. Design and logistical solution of the lature-walk tram. Art concept tram as a dynamic element of the urban environment.

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City Railway, whose wagons were driven by horses. Opening of the first electric tram in Samara. Sutkevich Pavel Antonovich - the creator of the Samara tram. Advantages of tram over other types of public transport.

abstract, added 11/23/2014


Familiarization with the concept of urban transport; His development abroad. Metropolitan, tram, trolleybus, bus, taxi as basic types of passenger transport. Search for more advanced solutions in terms of the organization of movement. Examples of solving problems.

examination, added 05/09/2014


Execution of calculations to evaluate the parameters of the transport network posted on the territory of the region or the state. Criteria for integrating the type of transport in the transport network of the region. Cargo and passenger transportation. Evaluation of the degree of transportation of transport.

coursework, added 05.11.2012


Freight transport: mixed and intermodal types. The basic principles of the functioning of the intermodal system. Distribution between modes of transport. Cargo flows and their characteristics. The quality of transport service cargo owners fleet.

abstract, added 11/30/2010


Characteristics of transported cargo. Methods of loading and unloading. The choice of rolling stock for the carriage of goods. Drawing up contracts for the transportation of goods on all routes. Accounting for driver time drivers. Drawing up the schedule of car traffic.

course work, added 12/19/2015


The appearance of the steam machine and the principle of its work. Construction of a railway in 1775 for the carriage of the rock on the Muses of Altai. Creating a first rail locomotive Richard Treventik. The advantages of the railway over the rest of the vehicles.

Amazing nearby We say, when we notice or find out the closer then, by anything, it was hundreds of times, but or did not know, or did not pay attention .... I would also add "Unknown around"For often in life they are surrounded by things so banal and familiar, that for some reason we think that we know everything about them ... where does such a conviction and confidence not understand ... It is also not clear why I have done a fair number of years, knowing Example that it is a tram, we know so little ... when and where he first appeared, as it looked, who was his predecessor ... These and many other interesting facts and parts from the history of tram and tram movement, we can find out if we show interest ...

Tram - This is a type of street rail public transport for the transport of passengers on specified (fixed) routes. Used mainly in cities. Probably will answer anyone who will be asked to characterize this type of social transport ...

Word tram derived from eng. tram (car, trolley) and way. (way). One of the versions, there was a trolley for the carriage of coal at the mines of the United Kingdom. As the type of transport, the tram is the oldest view of the city passenger public transport and originated in the first half of the XIX century - initially horse pull.

Konka

In 1852 french engineer Lubahe made a proposal to arrange rail tracks along the streets of large cities for the carriage of cars with horses. Initially, it was used only for cargo transportation, but after the construction of the first passenger lines of the Konka began to transport and passengers. Such a road was built by him in New York ....

Cuck on New York Street

and very soon a new type of transport has spread to other cities of America and in Europe.

Detroit Königsberg

Konka in Paris.

London

Sweden Czech Republic

"And what in Russia?" -probably ask you .... Soon the horse appeared here and here ....
In 1854 in the vicinity of St. Petersburg, near Smolensk Sloboda, engineer Polezhaev An equestrian road was arranged from longitudinal wooden bars, with an area of \u200b\u200biron. In 1860 engineer Domantovich built an equestrian road on the streets St. Petersburg.

Despite the low speed (no more than 8 km / h), a new type of transport soon spread and stuck in many major cities and provincial centers.

In Moscow at Serpukhov gate

in Minsk

Samara

Voronezh

in Tiflis

Kiev

Tashkent.

For example, in St. Petersburg, the equestrian railways were held in all significant highways from the center to the outskirts.

In most cases, the konka was built with the participation of foreign capital and if at the beginning, it had a positive effect on the development of the transport network in the cities, then over time, the development process was very slowed down.

History of electric tram

The prototype of electric trams was the car created by the German engineer rNST Werner von Siemens. It was first used in 1879 at the German industrial exhibition in Berlin. Locomotive was used to ride visitors through the exhibition.

Siemens & Halske Electric Railway at Berlin Exhibition 1879

The first electric tram appeared at the end of the XIX century - in 1881 in Germany in Berlin. Four cars clung to locomotive, each of which had six places.

Later, the train was demonstrated in 1880 in Dusseldorf and Brussels, in 1881 in Paris (in a non-working condition), in the same year in action in Copenhagen and finally in 1882 in London.
After success with an exhibition attraction, Siemens began to build an electric tram line 2.5 km in Berlin suburb Lighterfeld..

The wagon in the world in the world of the electric tram line in the former. Expiting Berlin Lighterfeld, openly 05/16/1881. The voltage is 180 volts, the engine power of 5 kW, the power was carried out through the running rails until 1890. Photo 1881

The engine carriage received a current through both rails. In 1881, the first tram, built by Siemens & Halske, passed through the railway between Berlin and Lighterfeld, thereby opening the tram movement.
In the same year with namesbuilt a tram line of the same type in Paris..

In 1885, the tram appeared in the UK in the English Resort City Blackpool . It is noteworthy that the initial areas are preserved in pristine form, and the tram transport itself is carefully preserved in this city.

Soon the electric tram became popular throughout Europe.
Haalle

Warsaw

View of the portal of the Rhine Bridge in Mannheim Cate for the adorable type of tram

tram in Barcelona

The appearance of the first trams in the United States occurred independently of Europe. Inventor Leo Dustoms(LEO DAFT) began experiments with electric burden in 1883, building several small electric locomotives. His work was interested in the director of Baltimoreskaya Konka, who decided to translate the three-mile line on the electric shirt. Dafa took up the electrification of the line and the creation of trams. On August 10, 1885, the electric tram movement was opened on this line - the first on the American continent.

Boston tram-bowl with open areas. USA.

However, the system turned out to be inoperable: the use of the third rail led to short circuit during the rain, besides, the voltage (120 volts) killed many of the unlucky small animals: (cats and dogs); Yes, and for people was unsafe. Soon the use on this line refused and returned to horses.

Cincinatti. Ohio. USA.

However, the inventor did not leave the idea of \u200b\u200ban electric tram, and in 1886 he managed to create a working system (instead of the third rail, a two-wire contact network was applied). The trams of the Dafete system were used in Pittsburgh, New York and Cincinnati.

Ice Tram St. Petersburg

In St. Petersburg under the contract with the owners of the end (he was concluded for 50 years) no other public transport should have been. In order to formally do not violate this contract, in 1885 the first electric tram rushed on the ice of the frozen Neva.

Sleepers, rails and poles for the contact network crashed right into the ice.

They were called "Ice Trams".

It is clear that you could use this type of transport only in winter,

however, what ended the time of trams on horse riding soon became completely clear.

Steam horse

Little-known, but the fact, except for traditional kons, were two more lines in St. Petersburg vapor. The first line of the steam tram or in common - parovikaIt was laid in 1886 by the Big Sampwehonian Avenue and the Second Murinsky Avenue, although this line was officially called the "line of steam equos-railway".

A steam room had a number of advantages in front of the end: higher speed, high power. Because of the resistance of the owners of the end of the end and the appearance of an electric tram, the locker did not receive development - the line of the steam tram from the area of \u200b\u200bthe uprising to the village of Rybatsky according to the current Prospectus of Obukhovsky defense became the last.

Also, at the beginning of the 1880s, the Pararik line was laid along the embankment of the Ligovsky Canal.

A steam locomotives were kept in the Vyborg Concommon Park. As a passenger transport of a steam tram of the slightly survived the competitor (last flight in 1922), but he again appeared on the streets of the Blood Leningrad for the transport of goods and weapons.

Electric tram in Russia.

Contractual obligations with the owners of the end of some cities detained the development of electric trams in them. Somewhere the path of the tram paired in parallel ways of the kink, to go bankrupt. Sometimes urban authorities simply redeemed the household of equestrian roads in order to turn the kink in the tram. Thus, the first electric tram in Russia was first launched not in St. Petersburg, as many mistakenly believe, but in Kieve..

Here he appeared in 1892. year on Alexandrovsky (Vladimir) descent. Builder - Siemens company. Quickly becoming popular, he literally flooded the whole city. Soon other Russian cities followed by the example of Kiev: the tram appeared in Nizhny Novgorod in 1896

IN Ekaterinoslava (now Dnepropetrovsk, Ukraine) in 1897,

in Moscow, the tram appeared in 1899

in Saratov

Smolensk

Electric horsehow else was called the tram, appeared in Tiflisand there was a rather branched network there.

Details about Tiflis tram can be found from Tiflis Guidebook 1903

In Odessa and in St. Petersburg - in 1907.

At the end of 1904, an international competition for the right to produce works was announced in the city of Duma. It took part three firms: "Siemens and Galsk", "Universal Electricity Company" and "Westingauz" ( english). On September 29, 1907, a regular movement of the electric tram through the streets of St. Petersburg was opened. The first line was from the main headquarters to the 8th line of Vasilyevsky Island.

St. Petersburg. Consecration of tram wagons

Details:

On Sunday, September 15, at 10 am In the Alexander Garden, invited to the grand opening of tram traffic along the line were gathered: the main headquarters, the Nikolaev bridge and the 7th line of Vasilyevsky Island. The public was missed in the garden by the audience, mostly occupied the opposite panel. At the entrance to the garden in 2 rows stood new wagons. Here the car trades and conductors in a new form were grouped. In the Alexander Square, a tent was sprawled, a prayer service was served there.
The first toast for the health of the sovereign proclaimed the urban head of the cutters, then the Gardener, Major General Drachevsky proclaimed the health of all urban self-government and his representative of the rubber. The chairman of the tram commission of the juices in long speech expressed his gratitude for the assistance in the construction of the tram of the Governance and Audit Commission. The urban head in his speech stressed that despite the difficulties of the task, almost 80% of all the work on the construction of the tram are carried out in one construction period. A pretty toast suggested the chief engineer of the Statsovich tram commission, who raised the glass for the tram worker, on his shoulders of the millpilion of tram works. This fair assessment of His work Anna heard workers, since their representative was not at the celebration.
At the end of the mulabrat, the guests entered the new wagons and made fare to the 7th line and back. Wagons are striking with their miniature. Wagons are striking with their miniature. Dachshund posted on prominent places: for a broken big glass - 7 rubles, for small - 8 rubles, for spoiled doors - 40 rubles. "I do not care and smoke is being prohibited." Wagons are divided by a partition for grade 2: in the first 14 seats, in the second 10. On the rear area there are 10 passengers, on the front 6. Carriage, apparently, worried, but the first test was withstanding with honor. In the first car opened the movement of the Grador Drachevsky and the urban head of the incisors.
Upon return, before opening the passenger traffic, the city head went to the head of the head car and, referring to the public, proclaimed: "Tram movement in St. Petersburg is open, Hurray!". There was a response "Hurray" of those present. The public rushed into the wagons, ahead of all the workers. Who is older, he laughed, and the workers took all the places. In the blink of an eye, there were calls from conductors and cars rolled with the first paid passengers. . "

After the appearance of an electric tram in 1907, Konka gradually suppressed them, on September 8, 1917, she disappeared completely. The use of kinks in Moscow continued until 1912.

Moscow

Old electric trams were quite unlike the modern. They were smaller with dimensions and less perfect. They did not have automatically closing doors, the front and rear sites were separated from the inner salon with the stabbing doors. On the front site, it was sitting on a high stool with metal legs and a thick round wooden seat himself traded. In front of him a high black engine. With the inscription "Dynamo" on the lid.
Inside the wagons were wooden seats. In some, they were in the form of sofas for two passengers with shared backs on one side of the car and chairs designed for one person, to another. At the end of each car was a place for the conductor. A special sign warned about it so that, God forbid, someone would not take on this place. The conductor (more often - the conductor) was often in service uniforms, and even just in a coat or fur coat. Through his shoulder, he hung a huge leather bag for money, and a table of tickets was strengthened on the belt. Tickets were different dignity, depending on the distance of the trip and the number of settlement stations. Tickets were very cheap. Then the cost became the same, and the conductor on the belt now hung a ticket video. From the conductor to the car carriage through the entire wagon under the ceiling was extended a thick rope. When the landing ended, the conductor pulled out for this rope, and the carriage was loudly ringing on the front site. There were no electrical signals. From the second wagon, the signal to the rear site of the first car was in the same conductor in the same way. Only waiting for him and controlling the landing into his car, the conductor of the first car could signal the trades on the end of the landing.
Standing passengers could be kept behind the tarp loops located along the entire salon and hanging on a thick wooden stick. These loops could move along with a passenger gliding along a stick. Later loops began to make plastic. Metallic handles were added on the backs of the bench, as well as the handles on the rustles between the windows. But it was already much later. Windows opened completely. They descended into the lower wall. Not allowed. This was written even on the signs of each window.

Small children had the right of free drive. But no one asked the age of the child. Just on the platbands of the salon doors was deeply embedded and the whimsal notch, according to which the growth of the child was determined and he needs to pay, or not. Above noted, the child has already had to pay for his passage.

Intercity trams

Trams, first of all, are associated with urban transport, but long-distance and suburban trams were also very common in the past.
Tram next route Pierrefitte - Cauterets - Luz (or back) in French Pyrinees. You can say a long-distance tram that is not quite usual.

This is one of the most picturesque places of the tram line in the border of the 19th and 20th centuries, decorated with a bridge called Pont de Meyabat.

Intercity Mountain Tram in France

In Europe, there was a network of long-distance trams of Belgium, known as the Netherl. Buurtspoorwegen. (literally transfer - "Local Railways")
The first section of local railways (between Ostend and Nuvport, now is part of the coast tram line) was opened in July 1885. Long-distance trams were also common in the Netherlands. As in Belgium, they were originally steam, but then the steam trams were replaced with electric and diesel. In the Netherlands, the era of long-distance trams ended on February 14, 1966.

Until 1936, from Vienna in Bratislava, it was possible to take a city tram.

Few people know, but there was a long-distance tram in Italy. Tied Solerno and Pompeii.

Intercity tram was in Japan between Osaka and Kobe..

After the heyday, the era of which fell for the period between the world wars, the tram decline began, but already somewhere since the 70s of the 20th century, there was a significant increase in the popularity of tram, including environmental reasons and thanks to technological improvements.

Interesting facts about the trams of the world

The largest tram network in the world is located in the Australian Melbourne
The oldest tram wagons, still used in normal operation - wagons No. 1 and 2 tram islands Maine (Manx Electric Railway). They were built in 1893 and operate on the Country line of Douglas EN Ramsey Length of 28.5 km]
The longest travel on the tram can be made in Germany, driving from Krefeld, or rather, his suburbs of St Tönis, in Witten. The length of the trip will be 105.5 km, to overcoming this distance, it will take about five and a half hours, and it will have to make a transplant eight times.
The longest tram route without transfers - the coastal tram (Netherl. Kusttram.) in Belgium. On this line 67 km there are 60 stops. There is also a line from Freudenstadt to Eringen through Karlsruhe and Hailbronne with a length of 185 km.
The northernmost tram system in the world is located in Trondheim.
In Frankfurt-on Main since 1960, there is a children's tram

By the third generation of trams include the so-called low-voltage trams. As follows from the name, their distinctive feature is the small height of the floor. To achieve this goal, all electrical equipment is made on the roof of the tram (on the "classic" trams, electrical equipment can be located under the floor). The advantages of a low-profile tram are convenience for disabled people, elderly, passengers with children's strollers, a faster landing and disembarkation.