In almost all four-stroke piston internal combustion engines, there is a gas distribution mechanism based on a camshaft. All about the camshafts, their existing types, design and features of work, as well as the correct choice and replacement of shafts, read the proposed article.

vigator (motors with a lower shaft arrangement); Head mounting (top shaft motors). Usually, there are no additional elements in the lower shafts; they are lubricated by oil mist in the crankcase and by supplying oil under pressure to the bearing journals through bushings. In the upper shafts, there is often a longitudinal channel and cross-drilled holes in the bearing journals - this ensures lubrication of the journals by supplying oil under pressure. The engine can have one or two RVs, in the first case one shaft drives all the valves, in the second case one shaft drives only the intake valves, the second only the exhaust valves. Accordingly, the number of cams on the common RV corresponds to the number of all valves, and on each of the separate RVs the number of cams is half the total number of valves. The RV drive can be carried out using a belt, chain or gear directly connected to the crankshaft gear. Today the most commonly used

The device and principle of operation of the camshaft

The car engine is a very complex mechanism, one of the most important elements of which is the camshaft, which is part of the timing. The correct operation of the engine largely depends on the accurate and smooth operation of the camshaft.

on the engine device, the gas distribution mechanism can have a lower or upper valve arrangement. Today, timing belts with overhead valves are more common. This design allows for faster and easier maintenance, which includes adjusting and repairing the camshaft, which requires camshaft parts. Camshaft arrangement From a structural point of view, the engine camshaft is connected to the crankshaft, which is ensured by the presence of a chain and a belt. The camshaft chain or belt slides over the crankshaft sprocket or camshaft pulley. A camshaft pulley such as a split gear is considered the most practical and effective option, therefore it is often used to tune engines in order to increase their power. The bearings, inside which the camshaft bearing journals rotate, are located on the cylinder head. If the neck mounts come out of

Constructive and technological characteristics of the part

The camshaft of an automobile engine is one of the critical parts. The operation of the engine as a whole is determined from the state of the main working surfaces of the shaft. The main defects of the engine camshafts are:

1. Wear of the camshaft bearing journals;

2. Wear of the cams in height;

3. Changing the cam profile;

4. Shaft bending.

All of the above camshaft defects cause knocking in the valve mechanism, a decrease in engine power, and an increase in bearing clearances, in addition, causes a drop in oil pressure in the lubrication system. The operation of the valve-distributor mechanism is theoretically estimated by a parameter called "cut time" and is characterized by the area limited by the curve of the change in valve lift over time.

Figure 5 shows the curves of changes in the area of \u200b\u200bthe valve-distribution mechanism. Shaded areas: the lower one characterizes the reduction in area as a result of cam wear along the profile.

A decrease in the "section time" of the valve as a result of the wear of these mating parts leads to a decrease in the filling time of the cylinders and a drop in engine power.

Figure: five. Change in area "time-section" with wear

valve and distribution mechanism

Restoration to normal dimensions of the valve lift is carried out by resurfacing the cam along the entire profile and is justified by the fact that if you remove the same (with respect to the unworn cam) layer of metal from the cam, the amount of valve lift and the moments of opening and closing the valve do not change. You only need to bring the clearance between the valve and the tappet to normal value (Fig. 6).

Figure: 6. Camshaft cam, ground to oversize

with saving the profile

The design dimensions and technical conditions for the manufacture and repair of the camshaft of the ZIL-130 car are given in Appendix. 3.

Objective:

1. To study the possible types of defects in the camshaft for those. conditions for control-sorting and establish existing defects on the controlled shaft;

2. To study the nature and magnitude of wear of the camshaft cams;

3. Acquire skills in using special fixtures and tools for measuring the shaft cams.

1. External inspection of the camshaft;

2. Measurement of all cam in 2 zones with determination of cam wear in height;

3. Determination of camshaft deflection;

4. Measurement of the camshaft bearing journals;

5. Building the profile of one cam.

Equipment, devices, tools:

1. Workbench for camshaft installation;

2. Device for measuring cam elements;

3. Tools:

a) micrometers 25-50, 50-75 mm;

b) indicator with a stand with an accuracy of 0.01 mm;

c) triangular scraper.

4. Technical conditions for control and sorting of parts during overhaul.

Research objects

Engine camshafts: GAZ-51, ZIL-130, M-21, YaMZ-236 (YaMZ-238), etc.

Work order:

1. Carry out an external inspection of the camshaft and record the results of the inspection in the report form.

2. By external inspection the following shaft defects are established:

a) spalls on the journals, gears and cams;

b) cracks of different sizes and locations;

c) local wear, scuffing and risks;

d) breakdown and clogging of the thread, wear, damage to the keyway, etc.

Measurements are established:

a) wear of the bearing journals;

b) wear of the cams in height;

c) shaft deflection.

3. Adjust the measuring tool.

4. Take measurements to the extent specified in this manual.

5. According to the results of external inspection and measurements of the camshaft in accordance with those. the conditions for control-sorting belong to one of 3 categories: a) suitable, b) not suitable, c) require repair.

6. Enter the measurement results into the report form and build the pusher lift curve for the new and changed cam.

7. Prepare a report, making a conclusion on the work.

8. Hand over the workplace to the laboratory assistant.

Determination of the repair size of the camshaft journals

Repair size: D p \u003d D z - Z,

where D p is the closest required repair size of the shaft journal, mm;

D z - measured diameter of the shaft neck, mm;

Z - machining allowance (per diameter).

Grinding allowance

where Z  - allowance, taking into account the uneven wear of the journals, Z \u003d 0.06 mm;

f - shaft deflection that cannot be straightened (permissible according to TU, f \u003d 0.05 mm;

Z h - allowance, taking into account the depth of the notches on the necks (the depth of the damaged layer Z h \u003d 0.08 mm);

 в - error of locating and fixing the shaft during grinding ( в \u003d 0.02 mm).

Work instructions:

1. Determination of the wear of the bearing journals.

To determine the wear of the bearing journals of the shaft, it is necessary to measure each journal of the shaft in 2 planes 1 - 1 (1st chord) and 2 - 2 (2nd chord), spaced 5 mm from the edges of the bearing journals (Fig. 2.7).

In each belt, the bearing journals are measured in 2 mutually perpendicular planes A - A, parallel to the plane of the keyway and plane B - B, perpendicular to the plane passing through the keyway.

When measuring journals, the camshaft should be mounted on prisms or at centers.

2. Determination of cam height wear.

To determine cam height wear:

a) measure each cam in 2 planes (fig. 7);

b) compare the obtained results of height measurements with the nominal height of the new cam and determine the amount of wear of the cams in height.

c) give an opinion on the possibility of further operation of the camshaft cams without repair, based on the permissible wear value for those. conditions or designate a method for restoring the cams to the nominal value.

Figure: 7. Camshaft cams measurement scheme

Determination of shaft deflection.

To determine the deflection of the shaft, the camshaft is installed in the center:

a) to the middle neck (with a symmetrical shaft arrangement), alternately bring the measuring rod of the indicator head;

b) set the rod of the indicator head to the position at which the small arrow gives a deviation of 1 - 2 mm and bring the zero of the movable scale to the large arrow,

c) orient the camshaft along the cam to be measured relative to the measuring device,

d) set the cam to the maximum lift position, which is determined by a small arrow reading when the camshaft turns,

e) turn the shaft 90 in either direction and set the indicator arrow to zero,

f) rotating the shaft, fix the cam lift according to the indicator readings, every 10 of the rotation angle. The maximum cam lift should correspond to an angle of rotation of 90 from the origin,

g) according to measurements and tabular data (for a new cam, see the poster), plot the cam lift curves (new and modified).

Reference data are presented in Appendix 2.

Control questions

List the main structural elements of the camshaft and its defects?

What parameters characterize the condition of the bearing journals and camshaft cams?

How to determine the largest neck size for which the repair size category is assigned?

How to check the camshaft for deflection?

In what sequence is the micrometer set to "0"?

How to check the cam profile of the camshaft?

1. INTRODUCTION

The growth of the car park in our country has led to the creation of a car repair production. The need to repair machines arises with their appearance, therefore, human activity aimed at satisfying this need exists as long as there are machines. A well-established repair facility maximizes the service life of vehicles. During the downtime of the car for repair, the company suffers losses. It is necessary to bring the car to the line as soon as possible, this is possible only with a quick and high-quality repair. To carry out such repairs, an accurate calculation of the sequence of operations, time and methods of eliminating defects is required.

More and more ATPs are paying great attention to the complex organization of restoration work. Complex restoration reduces repair time and labor intensity. Currently, there are many auto repair plants that are engaged in the overhaul of vehicles and their systems and assemblies. This allows to ensure higher reliability of the car in further operation and the car restored after major overhaul is 30-40% cheaper than the cost of a new car, which is very important for ATP. Many parts that are subject to restoration can be repaired can be repaired at an ATP that has special technological equipment, this for the enterprise will cost in a shorter time and in lower material costs.

It is necessary to rely on modern scientific knowledge and have a well-organized engineering service to effectively manage such a large field of activity as auto repair production. The organization of car repairs in our country is constantly paid great attention. Thanks to the development of effective methods for the restoration of worn parts, progressive technology of the dismantling and assembly complex of works and the introduction of more advanced technical means in the repair production, prerequisites have been created to increase the service life of cars after overhaul, although currently the service life of a repaired car is 60-70% of the resource of new cars and the cost of repairs remains high.

2 TECHNOLOGICAL PART

2.2 Operating conditions of switchgear

shaft ZIL - 130

During operation, the camshaft is subjected to: periodic loads from the forces of gas pressure and the inertia of the movement of masses, which cause alternating voltage in its elements; friction of the journals on the bearing shells; friction at high specific pressures and loads in the presence of abrasive; dynamic loads; bending and twisting, etc. They are characterized by the following types of wear - oxidative and violation of fatigue strength, molecular-mechanical, corrosion-mechanical and abrasive. They are characterized by the following phenomena - the formation of products of the chemical interaction of metals with the environment and the destruction of individual microdistricts of the surface layer with the separation of material; molecular seizure, material transfer, destruction of possible bonds by pulling out particles, etc.

2.3 The choice of rational ways to eliminate defects in the part

Defect 1

The wear of the bearing journals is ground to one of the repair dimensions. Grinding is carried out on a circular grinding machine. Since the simplicity of the technological process and the equipment used; high economic efficiency; maintaining the interchangeability of parts within a certain repair size.

Defect 2

When the thread is worn out, it is eliminated by vibration-arc surfacing, since a slight heating of the part does not affect their heat treatment, a small heat-affected zone, and a sufficiently high process productivity.

Defect 3

When the eccentric is worn, it is deposited and then grinded on a grinding machine. Since: simple technological process and use of equipment; high economic efficiency; maintaining the interchangeability of parts within a certain repair size.

2.4 Development of technological process diagrams, elimination of each defect in the departmentness

Table 1

Defects	Parts repair methods	Operation No.	Operations
1st circuit			Galvanic (iron)
Wear of bearing journals	Ironing		Grinding (grinding the neck) Polishing (polish the neck)
2nd scheme			Screw-cutting lathe
Thread wear M30x2	Submerged arc surfacing		(cut off worn threads) Screw-cutting lathe (grind, cut threads)
3rd scheme			Surfacing (weld
Worn keyway	Submerged arc surfacing		groove) Screw-cutting lathe (turn) Horizontal milling (mill groove)
4th scheme			Surfacing
Worn eccentric	Surfacing		(to melt the eccentric) Screw-cutting lathe (turn eccentric) Cylindrical grinding (grinding eccentric)

2.5 Plan of technological operations with the selection of equipment, fixtures and tools

No. p.	the name of the operation	Equipment	Gadgets	Tool
								working	Measure bodily
	Galvanic (iron-blasting)	Iron bath	Iron suspension	Isolation brush	Calipers
	Grinding (grind the necks		Leash cartridge	Grinding wheel L \u003d 450	Micrometer 25-50 mm
	Polishing (polish the necks)	Cylindrical grinding machine ZB151	Leash cartridge	Polishing wheel	Micrometer 25-50 mm
	Screw-cutting lathe (cut thread)			Through cutter with plateI5K6	Calipers
	Surfacing (weld the neck under the thread)	Installation for surfacing		Welding naya pro drag	Calipers
	Screw-cutting lathe (grind, cut a thread)	Screw-cutting lathe 1K62	Leader chuck with centers	Through cutter with plateI5K6	Calipers limiting threaded ring
	Surfacing (weld groove)	Installation for surfacing	Three-jaw self-centering chuck	Welding naya pro drag
	Screw-cutting lathe (turning)	Screw-cutting lathe 1K62	Leader chuck with centers	Through cutter with plateI5K6	Calipers
	Milling (milling a groove)	Horizontally- milling machine 6N82G	Kronshte- yn jack	Tsilin- driches- kaya milling cutter	Calipers
	Surfacing (weld exuentric)	Installation for surfacing	Three-jaw self-centering chuck	Welding naya pro drag	Calipers
	Screw-cutting lathe (grind the eccentric)	Screw-cutting lathe 1K62	Leader chuck with centers	Through cutter with plateI5K6	Calipers
	Cylindrical grinding (grind eccentric)	Cylindrical grinding machine ZB151		Grinding wheel L \u003d 150	Micrometer 25-50 mm

2.6 Brief description of equipment

Screw-cutting lathe 1K62

1 Distances between centers, mm 710, 1000, 1400

2 The largest processing diameter of the bar passing through the spindle, mm 36

Over support - 220

Over bed - 400

3 Spindle revolutions per minute 12.5, 16, 20, 25, 31.5, 40, 50, 63, 80, 100, 125, 160, 200, 250, 315, 400, 500, 630, 800, 1000, 1250, 1600, 2000

4 Longitudinal gears of the support in mm per 1 spindle revolution 0.07, 0.074, 0.084, 0.097, 0.11, 0.12, 0.13, 0.14, 0.15, 0.17, 0.195, 0.21, 0.23, 0.26, 0.28, 0.3, 0.34, 0.39, 1.04, 1.21, 1.4, 1.56, 2.08, 2.42, 2, 8, 3.8, 4.16

5 Cross feeds of the support 0.035, 0.037, 0.042, 0.048, 0.055, 0.065, 0.07, 0.074, 0.084, 0.097, 0.11, 0.12, 0.26, 0.28, 0.3, 1.04, 1.21, 1.04, 2.08, 3.48, 4.16

6 Electric motor power 10 kW

7 Overall dimensions of the machine, mm

Length 2522, 2132, 2212

Width 1166

Height 1324

8 Machine weight 2080-2290 kg

Cylindrical Grinding Machine

1 The largest diameter of the workpiece is 200 mm

2 Grinding wheel diameter, in mm 450-600

3 The greatest travel of the table 780 mm

4 Maximum transverse movement of the grinding wheel headstock 200 mm

5 Maximum length of the grinding piece 7500 mm

6 Power of the main electric motor 7 kW

7 The number of revolutions of the spindle of the grinding head per minute - 1080-1240

8 Number of revolutions of the headstock spindle per minute 75; 150; 300

9 Limits of speeds of longitudinal motion of a table meters per minute 0/8 $ 10

Horizontal milling machine 6Н82

1 Dimensions of the working surface of the table, in mm 1250х320

2 The greatest movement of the table, in mm

longitudinal - 700

transverse - 250

vertical - 420

3 Number of spindle revolutions per minute - 30; 37.5; 47.5; 60; 75; 95; 118; 150; 190; 235; 300; 375; 475; 600; 750; 950; 1180; 1500

4 Longitudinal and transverse feed, rpm - 19; 23.5; thirty; 37.5; 47.5; 60; 75; 95; 150; 190; 235; 300; 375; 475; 600; 750; 950

5 Vertical feeds are equal to 1/3 of the longitudinal

6 Power of the electric motor, in kW

reduced spindle - 7

reduced feed - 2.2

7 Machine dimensions, in mm - 2100х1740х1615

8 Machine weight, in kg - 3000

2.7 Selecting installation bases

Defect 1

When the bearing journals are worn, the locating base will be the journal for the timing gear and the gear for the thread.

Defect 2

When the thread is worn out, the support journals will be the locating base.

Defect 3

When the eccentric is worn, the locating base will be the journal for the timing gear and the gear for the thread.

2.8 Calculation of cutting conditions and times

2.8.1 Galvanic operation

1) Wipe the part with a rag;

2) Clean the surfaces to be coated;

3) Mount the parts on the suspension

4) Insulate areas that do not require coverage

5) Degrease the part

6) Rinse in cold water

7) Treat on the anode in a 30% acid solution

8) Wash in cold running water

9) Wash in hot water

10) Hang in the main bath

11) Soak in a bath without current

12) Switch on the current and gradually increase the current density

13) Apply a layer of metal

14) Unload the part from the bath

15) Rinse in cold water

16) Rinse in hot water

17) Neutralize in salt solution

18) Wash in hot water

19) Dry

20) Remove the part from the hanger

Main time:

The sum of the overlapping time before loading the parts into the bath:

∑ t op.n \u003d 2 + 0.4 + 0.4 + 0.5 + 10 + 10 \u003d 23.3

Time for loading the part into the main bath and for unloading from the batht v.n:

a) Time of movement of the worker during work 0.10 min

b) Time to move one suspension 0.18

c) loading and unloading the cart 0.18

d) time for loading parts into the bath and unloading 0.30

t v.n \u003d 0.1 + 0.18 + 0.18 + 0.30 \u003d 0.76

Total overlapping time:

134,7+(0,76+23,3)=158,76

Overlapped time:

Cleaning and wiping of parts 0.4; 0.28 min

Suspension mounting time 0.335 min

Time for insulation of uncoated surfaces 14.5 min

14,5+0,4+0,28+0,335=15,5

Piece by piece calculation time

Time to service the workplace

t \u003d 23.3 * 0.18

The number of parts simultaneously loaded into the bath

The number of baths simultaneously served by one worker

2.8.2 Cylindrical grinding

2) grind the necks;

3) remove the part.

Determine the speed of rotation of the processinge my details:

M / min, (10)

where C v - constant value depending on the processed material,

The nature of the wheel and the type of grinding;

d - Diameter of the processed surface, mm;

T - Resistance of the grinding wheel, mm;

t - Depth of grinding, mm;

β - Factor that determines the proportion of the width of the grinding wheel

K, m, x v, y v - exponents.

M / min.

Determine the speed:

RPM, (11)

where V D - grinding speed, m / min;

π \u003d 3.14;

d - diameter of the work piece, mm.

1000 4.95

n \u003d \u003d 105.09 rpm,

3.14 1.5

S \u003d β B, mm / rev, (12)

where B - width of the grinding wheel, mm;

β - coefficient that determines the proportion of the width of the grinding

Circle;

β \u003d 0.25 (L1 page 369 tab. 4.3.90 - 4.3.91).

S \u003d 0.25 1700 \u003d 425 mm / rev.

Determine the main time:

t o \u003d i K, min, (13)

n S

where L - estimated length of grinding, min;

y - The amount of cutting in and out of the tool, mm;

S - Longitudinal feed, mm / rev;

K - coefficient depending on the grinding accuracy and wheel wear,

(L1 p. 370);

i - the number of passes.

L \u003d l + B, mm, (14)

L \u003d 1.5 + 1700 \u003d 1701.5 mm

, (15)

Let's take: S \u003d 0.425 m;

K \u003d 1.4;

i \u003d 1.

Min.

t pc \u003d t o + t vu + t vp + t norm, min, (16)

where t about - main time, min;

t woo

t VP - auxiliary time associated with the transition, min.

Let's take: t vu \u003d 0.25 min;

t VP \u003d 0.25 min.

Min, (17)

Min, (18)

Min,

Min,

Min.

2.8.7 Screw-cutting lathe

1) install the part in the driver chuck;

2) cut off the worn out thread;

3) remove the part.

Determination of the amount of entry and exit of the tool:

Y \u003d y 1 + y 2 + y 3, mm, (55)

where y 1 - the size of the cutter penetration, mm;

U 2 - cutter overrun (2 - 3 mm);

U 3 - taking of test chips (2 - 3 mm).

Determine the amount of cutter penetration:

Mm, (56)

where t \u003d 0.2 mm - cutting depth;

φ – cutter entering angle (φ \u003d 45 º).

Mm,

y \u003d 0.2 + 3 + 3 \u003d 6.2 mm.

Determination of cutting speed:

Mm / rev, (57)

where С v, x v, y v - coefficients depending on working conditions;

K - correction factor characterizing specific

Working conditions;

S - cutter feed (0.35 - 0.7 mm / rev, L-1 page 244 tab.IV 3.52);

On the machine we acceptS \u003d 0.5 mm / rev;

C v \u003d 141 (L-1 p. 345 tab.IV 3.54);

x v \u003d 0.18 (L-1 p. 345 tab.IV 3.54);

g v \u003d 0.35 (L-1 p. 345 tab.IV 3.54);

K \u003d 1.60 (L-1 p. 345 tab.IV 3.54).

mm / rev.

Determine the number of revolutions:

RPM, (58)

where d - diameter of the treated surface, mm.

Rpm

Determination of the main time for the neck groove:

Min, (59)

where l \u003d 18 mm, length of the processed surface;

Y is the amount of cutter cutting, mm;

n - the number of revolutions;

S \u003d 0.35 - 0.7 mm / rev - cutter feed (L-1 p. 244 tab.IV 3.52);

On the machine we acceptS \u003d 0.5 mm / rev.

We will accept the nearestn \u003d 500 rpm.

Min.

Definition of piece time:

t pcs \u003d t о + t wu + t vp + t norm, min, (60)

where t about - main time, min;

t woo - auxiliary time for installation and removal of the part, min;

t VP - auxiliary time associated with the transition, min;

t vu IV 3.57);

t VP \u003d 0.25 min (L-1 p. 347 tab.IV 3.57).

Min, (61)

Min, (62)

Min,

Min,

Min.

2.9 Determination of piece - calculation time

Min, (92)

where t pcs - piece time, min;

T PZ - preparatory and final time, min;

Z - the number of parts in the batch.

Determine the size of the parts in the batch:

ΣТ пз

Z \u003d, (93)

Σ t pcs K

where ΣТ пз - total preparatory and final time for all

Operations, min;

Σ t pcs - total piece time for all operations, min;

K - seriality coefficient, 0.05.

2.10 Operation card

Table 5

	tool		t operas min		m / min	about	t about min	rpm	t in min
		Working								measuring
Surfacing 2. Weld on the tops of the cam 3. Remove the part	Grinding wheel	Calipers			3,71	65,64	54,26		0,22
Grinding 2. Grind the cams 3. Remove the part	Grinding wheel	Staples			4,95	105,09	10,67		0,25 0,25
Polishing 1. Install the part into the driver chuck. 2. Polishing the part. 3. Remove the part.	Abrasive belt	Staples			0,49	104,03	0,53		0,25 0,25
Grinding 1. Install the part into the driver chuck 2. Grind the necks 3. Remove the part	Grinding wheel	Staples			14,48	85,40	13,53		0,25 0,25
Surfacing 1. Install the part on the journal under the timing gear and the gear under the thread 2. To weld the necks 3. Remove the part	_____	Calipers			3,71	21,88	56,26		0,22
Oversized grinding 1. Install the part into the driver chuck 2. Grind 4 necks to fit the repair size 3. Remove the part	Grinding wheel	Staples		6,897	4,02	23,09	1,73		0,25 0,25

Continuation of table 5

Lathe 1. Install the part into the driver chuck 2. Cut off worn threads 3. Remove the part	Through cutter with plate	Calipers			38,076	505,25			0,25 0,25
Surfacing 1. Install the part into the support journal fixture 2. To weld the neck under the thread 3. Remove the part	______	Calipers			3,71	50,71	56,26		0,22
Lathe 1. Install the part into the driver chuck 2. Grind the neck and cut the threads 3. Remove the part	Straight through cutter with plate	Calipers			41,846	555,28			0,25 0,25
Milling 1. Install the part in the bracket or jack 2. Milling flat 3. Remove the part	Cylindrical cutter	Calipers				12,7	0,57		0,25 0,25
Locksmith 1. Install the part in a vice 2. Drive the thread 3. Remove the part	Die	Threaded ring	0,014

3 CONSTRUCTION PART

3.1 Description of the device and operation of the prisabout keeping

The device is designed to clamp the camshaft of the engine ZMZ - 402.10

The chuck is driven by a cam-type chuck. The chuck consists of a disc 8 attached to the flange of the stnak spindle, a floating slider 7, two cams 2 sitting on pins 4, pressed into the holes of the floating slider, rings 12 and 18, balls 13, bush 15, springs 1 and 17 , strip 24, protecting the slider from falling out, cover 10, casing 11, retainer 26 and other fasteners.

To install the shaft to be machined in the center, it is necessary to turn the casing 11 counterclockwise until the retainer 26 hits the groove of the ring 18. In this case

Achieved is the rotation of the cams 2 to the extreme position at which the shaft is installed.

When the machine is turned on, the latch 26 comes out of the groove of the ring 18, and at this time, under the action of the spring 1, the casing 11 rotates clockwise and with it the cover 10, the ring 12 and the cams 2, which are pressed against the workpiece. Under the action of the moment of the cutting forces, the part by the friction force grabs the cams pressed against its surface. The clamping force automatically increases with increasing torque.

Four sets of cams are used to secure shafts with a diameter of 20 to 160 mm.

The cartridge of this design is successfully used at machine-building plants in Czechoslovakia.

CONCLUSION

Completing the course project, I learned to choose rational ways to eliminate defects.

The methods and methods that I used in the calculations are not laborious and have a low cost, which has an important role for the economy of a car repair company.

These defects can be repaired at small enterprises where there is a turning, grinding and electroplating workshop, as well as the necessary specialists.

I also learned to use the literature, choose certain forms for calculating cutting conditions and time norms.

I learned how to draw up an operational map, learned what the main time is, the preparatory and final time, the time for installing and removing the part, the time associated with transitions, organizational and piece time.

I learned the structure and operation of the device, got acquainted with a brief description of the equipment, learned how to choose it to eliminate defects.

And also I learned to develop diagrams of the technological process, draw up a plan of technological operations with the selection of the necessary equipment, fixtures, tools.

Bibliography

1 Aleksandrov V.A. "Reference book of the standardizer" M .: Transport, 1997 - 450s.

2 Vanchukevich V.D. "Grinder's Handbook" M .: Transport, 1982 - 480s.

3 Karagodin V.I. "Repair of cars and engines" M .: "Masterstvo", 2001 - 496s.

4 Klebanov B.V., Kuzmin V.G., Maslov V.I. "Car repair" M .: Transport, 1974 - 328s.

5 Malyshev G.A. "Handbook of the technologist of auto repair production" M .: Transport, 1997 - 432s.

6 Molodkin V.P. "Handbook of a young turner" M .: "Moscow worker", 1978 - 160s.

7 "Methodological guidelines for course design" 2 part. Gorky 1988 - 120s.

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stamping rolling steel crankshaft

Introduction

1.1 Description of the spark plug

2. Analysis of the existing production technology of the ZIL-130 camshaft

2.3 Smelting pig iron

2.5 Siphon casting of steel

2.6 Section rolling of steel

2.8 Fitter-mechanical processing

2.9 Technology of hardening heat treatment

2.10 Control

3. Determining the production type of the crankshaft

3.1 Blast furnace process

3.2 Steel production

3.3 Siphon casting of steel

3.4 Hot metal forming

3.5 Hot die forging

3.6 Metalwork and heat treatment

4. Development of requirements for manufacturability of product design

4.1 Manufacturability requirements for the blast furnace process

4.2 Manufacturability requirement of the 45 Steel camshaft

4.3 Processability requirement for steel casting

4.4 Processability requirement for hot die forging

4.5 Manufacturability requirements for machining

4.6 Processability requirement for heat treatment

5. The latest technology in the production of casting

Conclusion

Introduction

The camshaft (camshaft) is an element of the timing (Gas Distribution Mechanism), which is responsible for the synchronization of the engine (intake and exhaust strokes). The camshaft is the shaft on which the cams are located, which are responsible for opening and closing the intake and exhaust valves.

The camshaft must withstand the engine operating mode at a variety of crankshaft speeds, at plus 1000 0 C in the cylinders and minus 50 0 C on the street, for hours, and sometimes days, continuously, almost without rest. In this case, the shaft must not only make the valves associated with it move, but also protect them from overloads. Only special steels or bleached cast iron, from which the camshafts of modern motors are made, can withstand such enormous loads, and even then, subject to their hardening heat treatment, good lubrication.

Purpose of the study: to study the technology of production of the camshaft

Research object: the process of the camshaft production technology.

Research subject: camshaft production technology.

Research objectives:

Examine the scientific literature on the topic.

Describe the detail.

Analyze the operating conditions of the camshaft.

Analyze what materials are needed to make a spark plug.

5. Describe each technological stage of the part production.

1. Production technology of the camshaft ZIL-130

1.1 Description of the spark plug

In internal combustion engines, the timely admission of a fresh charge of the combustible mixture to the cylinders and the release of exhaust gases is provided by a gas distribution mechanism.

The ZIL-130 engine has a gas distribution mechanism with an overhead valve arrangement.

The gas distribution mechanism consists of camshaft gears, a camshaft, pushers, rods, rocker arms with fastening parts, valves, springs with fastening parts and valve guides.

The camshaft is located between the right and left cylinder banks.

When the camshaft rotates, the cam runs onto the pusher and raises it together with the rod. The upper end of the rod presses on the adjusting screw in the inner arm of the rocker arm, which, turning on its axis, presses the valve stem with the outer arm and opens the inlet or outlet port in the cylinder head. In the engines under consideration, the camshaft acts on the pushers of the right and left cylinder banks.

The gas distribution mechanism with overhead valves makes it possible to improve the shape of the combustion chamber, the filling of the cylinders and the combustion conditions of the working mixture. The better shape of the combustion chamber also improves the compression ratio, power and efficiency of the engine.

The camshaft is used to open the valves in a specific sequence in accordance with the order of the engine.

Install it in the holes in the walls and the ribs of the crankcase. For this purpose, the shaft has cylindrical ground support journals. To reduce friction between the shaft journals and the supports, bushings are pressed into the holes, the inner surface of which is covered with an anti-friction layer.

On the shaft, in addition to the bearing journals, there are cams - two for each cylinder, a gear for driving the oil pump and an interrupter-distributor and an eccentric for driving the fuel pump.

From the front end of the camshafts of the ZIL-130 engine, the sensor of the pneumatic centrifugal limiter of the engine crankshaft speed is actuated. To reduce wear, the rubbing surfaces of the camshaft are hardened by heating with a high frequency current.

The camshaft is driven from the crankshaft by means of a gear transmission. For this purpose, a steel gear is mounted on the front end of the crankshaft, and a cast iron gear is mounted on the front end of the camshaft. The timing gear from turning on the shaft is held by a key and secured with a washer and a bolt wrapped in the end of the shaft. Both camshaft gears have helical teeth, which cause axial displacement of the shaft when the shaft rotates.

To prevent axial displacement of the shaft during engine operation, a flange is installed between the gear and the front bearing journal of the shaft, which is fixed with two bolts to the front wall of the cylinder block. Inside the flange, a spacer ring is installed on the shaft nose, the thickness of which is slightly greater than the thickness of the flange, as a result of which a slight axial displacement of the camshaft is achieved. In four-stroke engines, the working process takes place in four piston strokes or two revolutions of the crankshaft, i.e. during this time the intake and exhaust valves of each cylinder must open sequentially, and this is possible if the camshaft revolutions are 2 times less than the crankshaft revolutions , therefore, the diameter of the gear mounted on the camshaft is made 2 times larger than the diameter of the crankshaft gear.

The valves in the engine cylinders must open and close depending on the direction of movement and the position of the pistons in the cylinder. On the intake stroke when the piston moves from in. m. t. to n. m., the inlet valve must be open, and closed during the compression, expansion (stroke) and exhaust strokes. To ensure such dependence, marks are made on the gears of the gas distribution mechanism: on the tooth of the crankshaft gear and between the two teeth of the camshaft gear. When assembling the engine, these marks must match.

Pushers are designed to transfer force from the camshaft cams to the rods.

The rods transmit the force from the pushers to the rocker arms and are made in the form of steel rods with hardened tips (ZIL-130). The rocker arms transmit the force from the rod to the valve. They are made of steel in the form of a two-armed lever, planted on an axle. To reduce friction, a bronze bushing is pressed into the hole of the rocker arm.

The hollow axle is mounted in struts on the cylinder head. The rocker arm is held against longitudinal movement by a spherical spring. On ZIL-130 engines, the rocker arms are not equal arms. An adjusting screw with a locknut is wrapped in a short arm, abutting against the spherical surface of the rod tip.

The valves are used to periodically open and close the openings of the intake and exhaust channels, depending on the position of the pistons in the cylinder and on the order of engine operation.

In the ZIL-130 engine, the inlet and outlet channels are made in the cylinder heads and end with plug-in sockets made of high-temperature cast iron.

Figure 1. Cam profile: 1 - rest sector; 2 - acceleration sector; 3 - lateral surface; 4 - top; 5 - sector of maximum valve opening

The valve consists of a head and a stem. The head has a narrow, 45 or 30 ° beveled edge (working surface) called a chamfer. The chamfer of the valve must fit snugly against the chamfer of the seat, for which these surfaces are rubbed together. The intake and exhaust valve heads do not have the same diameter. For better filling of the cylinders with a fresh combustible mixture, the diameter of the intake valve head is made larger than the diameter of the exhaust valve.

1.2 Analysis of the operating condition of the cylinder head

The camshaft must withstand the engine operating mode at a variety of crankshaft speeds, at plus 1000 0 C in the cylinders and minus 50 0 C on the street, for hours, and sometimes for days, continuously, almost without rest. In this case, the shaft must not only make the valves associated with it move, but also protect them from overloads.

The most important element of the camshaft is the cam. The thick, or wide, part of it is intended for rest, the thin one is the most loaded. Absolutely all areas of the surface are important for him, which are shown with the corresponding names in Figure 1. Moreover, the importance and subtlety of calculating the profile of each part of the cam constantly increase as the maximum number of revolutions of the engines increases.

Turning with the shaft, the cam must select the thermal gap in the friction pair working with it and begin to lift the valve from the seat, preparing it for full opening. This is where the acceleration sector comes into play. The profile of this section of the cam determines the rate of valve lift and the nature of the increase in loads on the cam from the valve spring. In the free state, the spring presses the valve against the seat with a force of up to 15 kilograms. When the valve is fully opened, the spring resistance adds another 30 kilograms. If we take into account that the ratio of the lever arms in the valve drive is not in favor of the cam, then the load on it increases and in the maximum value can approach 50 kilograms. It is distributed only on a thin line over the entire width of the cam, the area of \u200b\u200bwhich, as a rule, is not more than 0.2 mm 2.

All these figures are approximate, but their values \u200b\u200bare close to the real ones for most passenger cars, and thanks to them it is possible to calculate the specific loads on the working surface area of \u200b\u200bthe cam. A rough calculation will give a value of 200 kg / mm 2.

Only special steels or bleached cast iron, from which the camshafts of modern motors are made, can withstand such enormous loads, and even then provided that they are hardened by heat treatment, good lubrication and precise observance of the working and resting times of the cams, which is determined by the clearances. It depends on the size of the "valve clearances" how - with a blow or gradually - the valve starts to open, and how - gently or with a rebound - it will sit back in the saddle.

The camshaft is affected by a whole range of external force factors that can cause its inoperability. The main reason for the failure of the RV is wear or chipping of the working surfaces of the cams. In order to successfully resist wear, the shaft must have a high hardness. However, the high hardness of the material throughout the entire volume can cause an increase in brittleness and, as a consequence, fatigue failure. Therefore, the best result is obtained by surface hardening of the camshaft material (carburizing, HFC hardening). This increases the hardness (and with it the wear resistance) of the surface layer, and the shaft core remains tough enough to successfully resist fatigue cracks.

Also, strict requirements are imposed on the accuracy of manufacturing individual shaft elements:

The bearing journals must be processed according to the 2nd class of accuracy and according to the 8th class of cleanliness; the runout of their dimensions relative to the extreme neck should not exceed 0.015-0.02 mm. The thrust end of the first neck must have a 7th grade of cleanliness, its perpendicularity to the neck must be no more than 0.02-0.03 mm. Ovality and taper of the necks no more than 0.01mm.

The working surfaces of the cams must be treated according to the 8th class of cleanliness. The axes of symmetry of the cams must be maintained with an accuracy of 0є30 "in relation to the keyway. The deviation of the axis of symmetry of the middle cam relative to the keyway should not exceed 0є30". The deviation of the symmetry axes of the remaining cams relative to the average should not exceed 0є20 ". The deviation from the theoretical lift of the flat pusher when checking the cam profile at individual points should be no more than 0.1-0.2 mm and from the nominal real position of the phases of the cams no more than 1є ... 2є ...

The displacement of the keyway axis relative to the diagonal plane should not exceed 0.02-0.03 mm.

The teeth of the ring gear of the oil pump drive and the distributor must be of the 7th class of cleanliness.

1.3 The choice of material for the manufacture of parts

Currently, a wide variety of materials and hardening methods are used, which is associated with the different nature of the operation of shafts, the scale, conditions and traditions of production at enterprises of various industries. The following options for the manufacture and hardening of camshafts are mainly used:

1. Shafts made of medium-carbon steels of grades 40, 45, 50, manufactured by hot stamping, with hardening of cams and bearing journals by surface hardening during surface induction heating. Most truck and tractor engine camshafts are manufactured using this method.

2. Shafts made of case-hardened steels (20X, 18XGT, etc.), hardened by carburizing followed by surface hardening with surface induction heating of cams and necks

In this case, the machining of the shafts by cutting is facilitated, but the overall labor intensity and complexity of heat treatment increases.

3. Cast shafts made of pearlitic gray and ductile iron, hardened by surface hardening during induction heating of the cams and necks, or by bleaching the working surfaces (spouts) of the cams.

Table 1. Composition of steel 40x SCh35

Chemical element

Table 2. Prices of materials

Characteristics of steel Steel 40:

Quality structural carbon steel, marked as steel 40, has a wide range of applications:

It is used to make crankshafts, camshafts, connecting rods, toothed rims, flywheels, gears, bolts, axles and other parts after improvement;

It is also used for the manufacture of medium-sized parts, which are subject to requirements for high surface hardness and increased wear resistance with low deformation, for example, long shafts, travel rollers, gear wheels, using additional surface hardening with HFC heating;

Limited weldability (to obtain high-quality welded joints, preheating to 100-120 degrees and annealing after welding is required), flock insensitivity, in addition, steel 40 is not prone to temper brittleness.

Mechanical properties possessed by steel 40: short-term strength limit - 520-600 MPa, proportionality limit - 320-340 MPa, relative elongation - 16-20%, relative contraction - 45%, impact strength - 600 kJ / sq. m., material hardness: HB 10 -1 \u003d 217 MPa

Characteristics of gray cast iron SCH35:

Despite the presence of graphite, the tightness of cast iron is sufficiently high if there are no casting defects in the casting. So, when tested with water or kerosene at a pressure of up to 10-15 MPa, bushings 2 mm thick have complete tightness. Cast iron castings with fine graphite and low P content in the absence of hairline cracks can withstand liquid pressures up to 100 MPa and gases up to 70 MPa.

The weldability of gray cast iron is significantly worse than that of carbon steel; therefore, gas and arc welding, as well as welding of defects (especially large ones) on castings, is carried out using a special technology.

The machinability of gray cast iron is inversely proportional to its hardness. It improves with an increase in the amount of ferrite in the structure, as well as with an increase in the homogeneity of the structure, i.e., in the absence of inclusions of phosphide eutectic, carbides with increased hardness in it. The presence of graphite is useful as the chips are crumbly and the pressure on the tool decreases.

Mechanical properties which gray cast iron SCh35 possesses: Modulus of elasticity E N / mm 2 * 10 -4 - 13-14.5; elongation, y,% - 0.6-0.9; bending strength, y, N / mm 2 - 630 \\, Material hardness: HB - 179-290 MPa.

Camshaft Requirements:

* Processing accuracy (The bearing journals must be processed according to the 2nd class of accuracy and according to the 8th class of cleanliness; the runout of their dimensions relative to the extreme neck should not exceed 0.015-0.02mm; The thrust end of the first neck must have the 7th class of cleanliness, its perpendicularity in relation to the neck is not more than 0.02-0.03 mm; The working surfaces of the cams must be processed according to the 8th class of cleanliness.);

* Wear resistance (The hardness of all hardened shaft elements is HRC 54-62)

* Low weight (15.7 kg);

* Balance.

According to the mechanical properties of making the camshaft from suitable materials, Steel 40 will be (according to the hardness of the material, low price).

2. Analysis of the existing production technology of the camshaft ZIL-130

2.1 Sequence of technical production

Preparation of material for blast furnace smelting.

Smelting pig iron

Getting steel in electric furnaces

Casting steel

Section rolling of metal by pressure

Stamping

Fitter-mechanical processing

Heat treatment

2.2 Preparation of materials for blast furnace smelting

The blast furnace works fine if it is loaded with lumps of optimum size. Too large pieces of ore and other materials do not have time to react in their inner layers during their lowering in the furnace, and part of the material is wasted uselessly; too small pieces fit tightly to each other, leaving no necessary passages for gases, which causes various difficulties in work, the most convenient material for blast furnace smelting are pieces up to 80 mm in diameter.

Therefore, the pieces of ore mined at the mines are sieved through the so-called screens, and pieces larger than 100 mm in diameter are crushed to the required size.

When crushing materials, as well as when mining ore in mines, along with large pieces, fines are formed, which are also not suitable for smelting in shaft furnaces. It becomes necessary to agglomerate these materials to the required size.

2.3 Smelting pig iron

Pig iron is obtained from iron ores in blast furnaces. Blast furnaces are the largest modern shaft furnaces. Most of the currently operating blast furnaces have a useful volume of 1300-2300 m3 - the volume occupied by the materials and smelting products loaded into it. These furnaces are about 30 m high and produce 2000 tons of pig iron per day.

The essence of blast furnace smelting is reduced to separate loading into the upper part of the furnace, called the top of the furnace, ore (or agglomerate), coke and fluxes, which are therefore located in the furnace shaft in layers. When the charge is heated due to the combustion of coke, which is provided by hot air blown into the furnace, complex physicochemical processes take place in the furnace (which are described below) and the charge gradually descends towards the hot gases rising up. As a result of the interaction of charge components and gases in the lower part of the furnace, called the hearth, two immiscible liquid layers are formed - cast iron and slag.

Materials are fed to the furnace by two skip hoists with tilting ladles with a capacity of 17 m3, delivering sinter, coke and other additives to the charging device to a height of 50 m. The charging device of the blast furnace consists of two alternately descending cones. For even distribution of materials on the top of the furnace, the small cone with the cylinder is rotated by a predetermined angle after each filling (usually 60 °).

In the upper part of the hearth there are tuyere holes (16-20 pcs.), Through which hot, oxygen-enriched air at a temperature of 900-1200 ° C is supplied to the furnace under a pressure of about 300 kPa.

Liquid cast iron is released every 3-4 hours alternately after two or three notches, which are opened for this with an electric drill. The cast iron pouring out of the furnace carries with it the slag that is above it in the furnace. Pig iron is directed along the gutters of the casting yard to pig iron ladles located on railway platforms. The slag poured out with the cast iron is preliminarily separated from the cast iron in troughs using hydraulic dams and sent to the slag trucks. In addition, a significant portion of the slag is usually tapped from the blast furnace prior to tapping the pig iron through the slag taphole. After the release of cast iron, the taphole is closed by plugging it with a refractory clay plug using a pneumatic gun.

Conventionally, the process taking place in a blast furnace can be divided into the following stages: combustion of fuel carbon; decomposition of charge components; reduction of oxides; carburizing iron; slagging.

The combustion of fuel carbon occurs mainly near the tuyeres, where the bulk of the coke, when heated, meets with air oxygen heated to 900-1200 ° C, entering through the tuyeres.

The resulting carbon dioxide, together with nitrogen in the air, rises and, meeting with hot coke, interacts with it according to the reaction

CO2 + C \u003d 2CO

The decomposition of the components of the charge proceeds in different ways - depending on its composition. When working on brown iron ore, the most important processes here are the destruction of hydrates of iron oxide and aluminum oxide, the decomposition of limestone by reaction

CaCO3 \u003d CaO + CO2

Reduction of oxides can take place with carbon monoxide, carbon and hydrogen. The main purpose of the blast furnace process is the reduction of iron from its oxides. According to the theory of Academician Baikov, the reduction of iron oxides proceeds stepwise according to the following scheme

Fe2O3 -Fe3O4 -FeO -Fe

Carbon monoxide plays the main role in the reduction of oxides

ЗРе2О3 + СО \u003d 2Ре3О4 + СО2

This reaction is practically irreversible, proceeds easily at a very low CO concentration in the gas phase. For the development of this reaction to the right, a temperature of at least 570 ° C and a significant excess of CO in gases are required

Fe3O4 + CO \u003d ZFeO + CO2 - Q

Then a hard iron sponge is formed

FeOtv + CO \u003d Fetv + C02 + Q3.

One of the main indicators of the operation of blast furnaces used to compare the performance of different plants is the utilization rate of the useful volume of the blast furnace (KIPO):

It is equal to the ratio of the useful volume V (m3) to the daily production of cast iron Q (t). Since the productivity of the furnace Q is in the denominator in the formula, the lower the utilization rate of the useful volume of the blast furnace, the better it works. The average KIPO in the USSR in the early 1970s was about 0.6, while in 1940 it was 1.19, and in 1913 - 2.3.

The best KIPO, equal to 0.39-0.42, has been achieved in recent years at the Cherepovets Metallurgical Plant.

For the production of pig iron, in addition to blast furnaces, various auxiliary equipment is used. Air heaters are the most important among them. For the successful operation of a modern blast furnace with a volume of 2,700 m3, it is required to blow about 8 million m3 of air and 500,000 m3 of oxygen per day using powerful blowers.

2.4 Getting steel in electric furnaces

The production of steel in electric furnaces increases from year to year, since a higher temperature and a reducing or neutral atmosphere can be obtained in them, which is very important when smelting high-alloy steels.

For steel production, three-phase electric arc furnaces with vertical graphite or carbon electrodes and a non-conductive hearth are most often used. The current heating the bath in these furnaces passes through the electrode - arc - slag - metal - slag - arc - electrode circuit. The capacity of such furnaces reaches 270 tons.

The furnace consists of a cylindrical metal casing and a spherical or flat bottom. The inside of the furnace is lined with refractory materials. Like open-hearth furnaces, arc furnaces can be acidic and basic. In the main furnaces, the hearth is laid out of magnesite bricks, on top of which a rammed layer of magnesite or dolomite (150-200 mm) is made. Accordingly, in acidic furnaces, dinas bricks and quartzite-on-liquid glass packing are used.

Furnaces are loaded through a window (using troughs and a filling machine) or through the roof (using a loading bucket or mesh). In this case, the roof with the electrodes is made removable and during the loading period it is raised, and the furnace is taken to the side and the complete furnace cage is loaded with a bridge crane at once or in two steps. After that, the oven is quickly covered again with the roof.

Obtaining steel in electric arc furnaces has undeniable advantages: high quality of the steel produced, the ability to melt any steel grades, including high-alloy, refractory and heat-resistant; minimal waste of iron in comparison with other steel-making units, minimal oxidation of expensive alloying additives due to the neutral atmosphere of the furnace, ease of temperature control.

The disadvantages are: the need for a large amount of electricity and the high cost of processing. Therefore, electric arc furnaces are used mainly to obtain high-alloy steels.

2.5 Siphon casting of steel

Casting steel is the process of pouring liquid steel from a casting ladle into molds-metal receivers, where the metal solidifies, forming ingots. Steel casting is an important stage of the production cycle, during which many physical and mechanical properties of the metal are formed, which determine the quality characteristics of finished metal products.

In steelmaking, molten steel from a ladle is poured either into molds or in continuous casting plants. There are 2 ways of pouring steel into molds - from above and by a siphon (there is also a conditionally third casting method - a siphon from above, but it is not widely used and therefore is not considered in this article). In the first case, the steel goes directly from the ladle to the mold; after filling the mold, the hole in the ladle is closed, the ladle is moved to the next mold with a crane, and the process is repeated. Siphon casting makes it possible to simultaneously fill several molds (from 2 to 60) with a metal melt, installed on a pallet, in which there are channels lined with hollow refractory bricks; steel from the ladle is poured into the central gating system, then it enters the molds from below through channels in the pallet. The choice of method depends on the range of steels, the mass and purpose of the ingots, and other factors.

Figure 2. Siphon casting of steel. 1-cast iron pallet, 2 - mold, 3 - casting ladle, 4 - central sprue, 5 - refractory mass, 6 - slag catchers, 7 - siphon brick

The siphon method, as a rule, is used to cast ingots of small weight, however, the trends of recent years show that this method is becoming more widespread when casting large ingots weighing up to several hundred tons. This is due, firstly, to the fact that the current level of development of the out-of-furnace processing technology makes it possible to reproducibly provide a low hydrogen content and, accordingly, there is no need for vacuum casting. Secondly, with siphon casting, there is the possibility of a less expensive (than casting in vacuum) and, at the same time, a sufficient reliable method of protecting the metal jet from secondary oxidation. Thirdly, this casting method makes it possible to stabilize the nitrogen content in the finished metal (important for steel grades alloyed with nitrogen). And finally, fourthly, modern refractory materials make it possible to practically eliminate the contamination of the metal by exogenous inclusions from the siphon channels.

Advantages of the siphon casting method in relation to casting from above - obtaining a high quality of the surface of the ingot, associated with the fact that the metal comes from the bottom and rises relatively slowly and calmly, in this regard, the ingots cast by the siphon method do not require peeling and significant cleaning; exclusion of the ingot part due to the absence of the need for its presence (the pen is used to reduce the time of the spray jet when it hits the bottom of the mold at the first stages of casting due to the faster creation of the molten metal pocket); the possibility of simultaneous casting of several ingots, which allows pouring a large mass of metal at once without interrupting the jet, equal to the mass of each individual ingot, multiplied by the number of molds poured simultaneously; simplification of the system for protecting the metal surface on casting from secondary oxidation: for this, all molds are closed with lids, under which argon is introduced; the entire siphon supply is inflated with argon; the casting ladle is lowered until the gate touches the riser receiving funnel; with careful assembly of the composition with molds, careful handling of the siphon supply (without fear of spoiling), you can pour clean steel that has undergone deep refining in metal finishing installations; casting time is shorter because several ingots are cast simultaneously, while melting of a large mass can be poured into small ingots; Siphon casting makes it possible to control over a wider range of the filling rate of the molds and to monitor the behavior of the metal in the molds throughout the entire casting period. The disadvantages of the siphon method for casting metal is the displacement of the heat center to the bottom of the ingot, and, as a consequence, the deterioration of the conditions of directed (bottom-up) solidification and, accordingly, an increase in the likelihood of the formation of axial looseness; the need to heat the metal before casting to a higher temperature due to the cooling of the metal in the center and siphon tubes and due to the lower casting speed than when pouring from above; increased costs for gating system refractories; increased pollution by exogenous inclusions from the siphon wiring; increased metal consumption for the gating system (from 0.7 to 2% of the mass of the poured metal); increased labor intensity in the assembly of foundry equipment.

Install pallets strictly horizontally (level). The temperature of the pallet before the set must be at least 100 ° C. Siphon supplies (stars, cups, spans and end tubes) intended for the pallet assembly must be dry and free from chips and cracks. The collection of pallets begins with placing on a hearth of dry sand or sifted through a sieve with a 3 mm cell of waste generated during disassembly of the pallets. When stacking an even number of streams, siphon bricks with lubricated collars are placed simultaneously in two opposite channels of the pallet, starting with an asterisk. Each brick is rubbed against the previously laid one. Half a normal brick is laid at the ends of the streams, and both streams are simultaneously wedged. The gaps between the siphon brick and the pallet are covered with dry sand or waste sifted through a sieve. The backfill is thoroughly rammed, and the seams are poured with 25 ... 30% aqueous solution of sulfite-alcohol stillage.

Prepared molds must be installed on the tray steadily, strictly vertically. Place an asbestos cord between the tray and the mold. When installing the molds, it is forbidden to hit the mold against the pallet and center.

Before feeding the metal for casting, the oxygen activity in the metal melt and its temperature should be measured. The metal temperature should be 80 ... 110 ° C higher than the liquidus temperature for a given steel grade. The oxidation of the metal is determined by the requirements for the chemical composition and contamination with non-metallic inclusions.

For thermal insulation of the metal mirror and its protection against secondary oxidation, slag mixtures should be used: lime-cryolite, fuel-free slag mixtures (green-graphite). The consumption of slag mixtures is 2 ... 3.5 kg per ton of liquid steel. The slag mixtures are fed into the mold before pouring in dense three to four-layer paper bags. The time for filling the mold with metal to the profit is 5.5 ... 6 minutes. The time of filling the profit should be approximately at least 50% of the time of filling the ingot body. The pouring of the metal is directly controlled by the master of the smelting section, who observes the surface of the rising metal in the mold and controls the rate of filling of the metal in the mold. When filling the mold, it is necessary to avoid turning the crust and boiling of the metal at the walls of the mold.

Siphon casting of steel allows for a wide range of regulation of the ingot filling speed. The normal casting speed is considered to be such a speed at which the metal rises calmly, without splashes. After filling 2/3 of the profitable extension, a part of the insulating mixture is poured onto the metal surface and casting is continued at a low speed. After the end of casting, the rest of the insulating mixture is poured. Take a metal sample when the metal enters the profitable part and the jet speed is reduced.

Features of siphon casting:

In the case of siphon casting of steel, the zone of intensive metal circulation is constantly located in the lower part of the ingot, and the heat center is also located here. This contributes to the blurring of the hard metal crust and, accordingly, causes a decrease in its thickness. Moreover, this takes place where the ferrostatic pressure reaches its maximum value. These conditions delay the formation of a gap in the lower part of the ingot and create inhibition of steel shrinkage along the height of the ingot, which can lead to the formation of transverse cracks on the surface of the ingot.

As a rule, small-weight ingots are cast by the siphon method. Meanwhile, with the transition to siphon casting of ingots weighing more than 20 tons, the probability of the development of shrinkage defects in the axial part of the ingot increases. In this case, the location of the thermal center in the lower part of the ingot can lead to a corresponding displacement of the zone of axial porosity. The figure below shows an ingot with a mass of 435 t from NiCrMoV steel (H / D 1.15), intended for a generator rotor with a mass of 200 tons, made at the Thyssen Heinrichshutte plant by the siphon method. The zone of axial shrinkage porosity in this ingot has shifted to its lower part.

When casting from above, the zone of the most intensive circulation of liquid steel moves sequentially from bottom to top. The maximum ferrostatic pressure is absorbed by the already completely solidified, strong shell of the ingot.

The lower part of the ingot, cast from the top, crystallizes under conditions of relatively calm state of steel, that is, at a higher rate, which leads to a more rapid formation of a gap between the ingot and the wall of the mold. The inhibition of shrinkage along the height of the ingot is reduced. For this reason, when pouring steel from above, it is possible to pour steel at a higher speed than when casting by a siphon method.

In the process of siphon casting, liquid steel, flowing through the channels of the gating system, inevitably comes into contact with the refractories. In this case, due to a sharp change in temperature, small cracks are formed on the inner surface of the brick, leading to chipping (peeling) of the brick. Refractory particles that have broken off from the channel surface contaminate the steel. Subsequently, with the simultaneous action of high temperature and deoxidation products on the siphon brick, the surface layer of the siphon refractory softens. Oxides and steel deoxidation products penetrate into the formed pores; interacting with the refractory, they form low-melting compounds, which are washed off by the moving stream of metal and also fall into the ingot. The greatest contamination of steel by exogenous inclusions occurs at the end of filling the molds, when the siphon refractory is softened to a greater extent. The nature of erosion of siphon refractories depends on their quality and the chemical composition of the cast steel. With a satisfactory quality of siphon refractories, the surface of the solidified metal sprue is smooth and shiny, and, conversely, with a low quality of siphon refractories, the solidified sprue has a rough surface.

With an unsatisfactory quality of refractories during siphon casting, steel contamination with exogenous non-metallic inclusions can occur to a greater extent than when casting from above. Moreover, a sufficiently large number of such inclusions can remain in the lower part of the ingot.

However, the issue of eliminating the listed disadvantages can be solved by using high-quality refractories, therefore, the choice of refractories and the preparation of the gating system and pallet should be given special attention.

2.6 Section rolling of steel

Rolling - reduction of metal between rotating rolls with a change in the shape of the cross section or the ratio of the geometric dimensions of the section. Due to the action of friction forces, the ingot or billet is drawn by the rolls into the gap between them, compressed in height and stretched along the length and width. In this case, the workpiece takes the form of a gap between the rolls, called a groove.

Rolling is used to produce rails, construction beams of various cross-sections, sheets of various thicknesses, bar stock, pipes, i.e., the main products for the development of many types of industry, construction and transport.

The rolling scheme is shown in Figure 3.

As follows from the diagram, two rolls set at a distance h (slot), rotating in different directions, capture due to friction a workpiece having a height H, which passes between the rolls in the direction of the arrow. In the process of passing between the rolls, the height of the workpiece H decreases to h, and the length increases. The H-h value is called the absolute compression rate, and the (H-h) / H * 100% ratio is called the compression ratio, or relative compression.

Figure 3. Diagram of the rolling process

Figure 4. Rolls for rolling metal: a - sheet, b - profiles

Figure 4 shows the rolls for rolling sheets and profiles. A group of rolls installed in a frame forms a so-called stand.

Several interconnected stands equipped with special auxiliary devices make up the rolling mill.

Mills, depending on the manufactured products, are sheet rolling (sheet production), section rolling (production of beams, rods, strips), tube rolling (pipe production), rail and girder and special mills.

Rolling mills also differ depending on whether the metal is processed in hot or cold condition.

Depending on the number of rolls, the rolling mills are two-roll, three-roll, multi-roll. Mills are called reversible if rolling is carried out both in one and in the opposite direction.

Over the past two decades, Soviet designers have created many rolling mills with high productivity and very high rolling speeds. The thin strip rolling mill can produce up to 35 m / s of finished products. Metal moves here at a speed of 125 km / h, that is, at the speed of the fastest train.

Large-capacity rolling mills designed for pre-crimping large ingots are called blooming and slabbing mills. Blooming mills with roll diameters from 840 to 1150 mm make it possible to obtain products in the form of swaged ingots with a cross section of 140 x 140 to 450x450 mm. Such compressed square-section ingots (blooms) weigh up to 10-12 tons or more.

Slabbing mills are powerful mills for rolling sheet billets up to 250 mm thick and up to 5 m long. Both blooming and slabbing machines have an enormous productivity from 1.5 to 2 million 1 ingots per year.

The need to obtain large ingots is explained by the fact that the growing demand for metal forces the furnaces to be enlarged, while casting steel from large furnaces into small molds is difficult and economically unprofitable.

Types of rental. Rolled metal is called rolled metal. Hire is divided into the following main types: sheet, section, pipes.

The rolling of this profile, depending on the steel grade and dimensions, is carried out in different ways (Figure 5).

Figure 5. Methods I-X of round steel rolling:

I - oval, rhombus or hexagon; II. IV. V - smooth barrel or box gauge; III - decagonal or box gauges; VI - square or hexagonal gauges; VII - circle, etc .; VIII - lancet caliber, smooth barrel or box caliber; IX, X - oval, etc.

Methods 1 and 2 differ in the options for obtaining a pre-final square (the square is precisely fixed diagonally and it is possible to adjust the height). Method 2 is universal, as it allows you to obtain a number of adjacent sizes of round steel (Fig. 2). Method 3 is that the pre-finishing oval can be replaced with a decagon. This method is used for rolling large circles. Method 4 is similar to method 2 and differs from it only in the shape of the rib gauge. The lack of sidewalls in this caliber contributes to better descaling. Since this method allows wide adjustment of the dimensions of the strip emerging from the rib gauge, it is also called universal sizing. Methods 5 and 6 differ from the others in higher hoods and greater stability of ovals in the wires. However, such calibers require precise adjustment of the mill, since with a small excess of metal, they overflow and form burrs. Methods 7-10 are based on the oval-circle calibration system

Comparison of possible methods for producing round steel shows that methods 1-3 allow in most cases to roll the entire range of round steel. Rolling quality steel should be carried out according to methods 7-10. Method 9, as it were, intermediate between the oval-circle and oval-oval systems, is most convenient in terms of regulating and setting the mill, as well as preventing sunsets.

In all of the considered methods of rolling round steel, the shape of the finishing and pre-finishing calibers remains almost unchanged, which contributes to the establishment of general laws governing the behavior of the metal in these calibers for all rolling cases.

Figure 6. Example of calibration of round steel according to method 2

The construction of a finishing gauge for round steel is as follows.

Determine the calculated diameter of the caliber (for a hot profile when rolling by minus) dg \u003d (1.011-1.015) dx is part of the tolerance + 0.01dx where 0.01dx is the increase in diameter for the above reasons: dx \u003d (d1 + d2) / 2 - diameter of a round profile in a cold state. Then

dg \u003d (1.011-1.015) (d1 + d2) / 2

where d1 and d2 are the maximum and minimum allowable diameters.

Prefinishing wheel gauges are designed taking into account the accuracy required for the finished profile. The more the shape of the oval approaches the shape of a circle, the more accurately the finished round profile is obtained. In theory, an ellipse is the most suitable profile shape for obtaining a correct circle. However, it is rather difficult to maintain such a profile when entering the finishing round gauge; therefore, it is used relatively rarely.

The flat ovals are well held by the wires and also provide large crimps. At small reductions of the oval, the possibilities of fluctuations in size in a round caliber are very insignificant. However, the opposite phenomenon is true only for the case when a large oval and a large hood are used.

For round profiles of medium and large sizes, ovals outlined by one radius turn out to be too elongated along the major axis and, as a result, do not provide reliable grip of the strip by the rolls. The use of sharp ovals, in addition to the fact that it does not provide an accurate circle, has a detrimental effect on the durability of the round groove, especially in the output mill stand. The need for frequent roll changes drastically reduces the productivity of the mill, and the rapid development of calibers leads to the appearance of second grades, and sometimes rejects.

The study of the reasons and mechanism for the development of calibers showed that the sharp edges of the oval, which cool faster than the rest of the strip, have significant resistance to deformation. These edges, entering the finishing stand roll groove, act on the groove bottom as an abrasive. Rigid edges at the tops of the oval form grooves at the bottom of the gauge, which lead to the formation of protrusions on the strip along its entire length. Therefore, for round profiles with a diameter of 50-80 mm and above, a more accurate profile execution is achieved by using two and three radius ovals. They have approximately the same thickness as the oval, outlined by one radius, but due to the use of additional small radii of curvature, the width of the oval is reduced.

Such ovals are flat enough to hold them in the wires and provide a secure grip, and a more rounded oval contour, approaching in its shape to the shape of an ellipse, creates favorable conditions for uniform deformation along the width of the strip in a round caliber.

2.7 Hot die forging technology

Forging is a process for producing forgings, in which the forming cavity of the die, called the stream, is forcibly filled with the metal of the original workpiece and redistributed in accordance with the configuration specified in the drawing.

Stamping can be used to produce products of very complex shape, which cannot be obtained by open-die forging.

Forging is carried out at different temperatures of the original workpiece and, in accordance with the temperature, is divided into cold and hot. The most widespread is hot forging (HOB), which is carried out in the temperature range that provides the removal of hardening. The technological process depends on the shape of the forging. In terms of shape, forgings are divided into two groups: discs and elongated forgings.

The first group includes round or square forgings having a relatively short length: gears, discs, flanges, hubs, covers, etc. Stamping of such forgings is performed by upsetting into the end of the original blank using only stamping transitions.

The second group includes elongated forgings: shafts, levers, connecting rods, etc. Stamping of such forgings is performed by broaching the original blank (flat). Before the final stamping of such forgings in stamping strands, it is required to shape the original blank in blank stamping strands, by free forging or on forging rollers.

Stamping schemes:

Since the nature of the metal flow during stamping is determined by the type of stamp, this feature can be considered the main one for the classification of stamping methods. Depending on the type of stamp, stamping is distinguished in open and closed stamps (Figure 7).

Figure 7. Punching schemes:

a) open stamp: b) closed stamp; c) closed stamp with two mutually perpendicular parting planes

Stamping in open dies (Figure 8, position a) is characterized by a variable gap between the movable and stationary parts of the stamp. Part of the metal flows out into this gap - a flare, which closes the exit from the die cavity and forces the rest of the metal to fill the entire cavity. At the final moment of deformation, surplus metal in the cavity is squeezed out in the flare, which makes it possible not to impose high requirements on the accuracy of the workpieces in terms of mass. All types of forgings can be obtained by stamping in open dies.

Stamping in closed dies (Figure 8, position b) is characterized by the fact that the die cavity remains closed during the deformation process. The gap between the movable and stationary parts of the stamp is constant and small, the formation of a flash in it is not provided. The device of such stamps depends on the type of machine on which they are stamped. For example, the lower half of the die can have a cavity, and the upper half has a protrusion (on presses), or the upper half has a cavity and the lower half has a protrusion (on hammers). A closed stamp can have two mutually perpendicular parting planes (Figure 7, position c).

When stamping in closed dies, it is necessary to strictly observe the equality of the volumes of the workpiece and the forging, otherwise, if there is a lack of metal, the corners of the die cavity are not filled, and if there is an excess, the size of the forging in height will be greater than the required one. Parting of workpieces must ensure high accuracy.

A significant advantage of stamping in closed dies is a reduction in metal consumption due to the absence of flash. The forgings have a more favorable structure, since the fibers flow around the forging contour, and are not cut at the point where the metal exits into the flare. The metal is deformed under conditions of all-round non-uniform compression at high compressive stresses, this makes it possible to obtain large degrees of deformation and to stamp low-plastic alloys.

2.7 Fitter-mechanical processing

The stamped camshafts are heat treated to relieve internal stresses and provide the desired material hardness.

Machining of ends and center holes on the shafts is carried out on double-sided milling and centering machines. Turning the journals and trimming the ends are performed on multi-cutter semi-automatic turning machines with one-sided, double-sided (rotation for both ends of the shaft) or central (rotation for the middle journal) drive. In the last two cases, the twisting of the shaft during processing is significantly reduced.

Due to the low rigidity of the camshafts and the possibility of their deflection from the cutting forces, the journals and cams are machined using rests. For this purpose, the middle journal of a four-cylinder engine or two middle journals of a multi-cylinder engine, after centering the workpiece, are roughly and cleanly machined under a steady rest. Shaft journals are ground on cylindrical grinding machines in centers.

The cams have a complex shaped profile, and their processing requires the use of copying machines. Turning of the cams is carried out on copy-turning semi-automatic machines. To obtain the required profile of the cam during its turning, the cutter installed in the tool holder must be appropriately displaced relative to the axis of rotation of the shaft in the transverse direction. To ensure favorable cutting conditions (creating the necessary cutting angles), the tool must also rotate depending on the angle of the cam line at this point. Both of these movements on the machine are created using the appropriate cam mechanisms.

Figure 8. Schematic diagram of turning a camshaft cam on a copying lathe: 1 - workpiece; 2 - copy shaft; 3 - copier

Figure 8 shows a schematic diagram of turning a cam on a copying lathe, the workpiece being worked out, the copy shaft and the copier rotate synchronously. The tracer shaft generates radial movement of the cutter in accordance with the cam profile, and the tracer rotates the cutter, keeping the cutting angle constant. Longitudinal feed is provided by moving the workpiece relative to its axis. To prevent bending of the shafts, support rests are used.

...

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1. INTRODUCTION

2 TECHNOLOGICAL PART

2.7 Selecting installation bases

2.8.1 Surfacing

2.8.2 Grinding

2.8.3 Polishing

2.8.4 Grinding

2.8.5 Surfacing

2.8.7 Turning

2.8.8 Surfacing

2.8.9 Turning operation

2.8.10 Milling

2.9.1 Surfacing

2.9.2 Grinding

2.9.3 Polishing

2.9.4 Grinding

2.9.5 Surfacing

2.9.6 Grinding

2.9.7 Turning

2.9.8 Surfacing

2.9.9 Turning

2.9.10 Milling

2.10 Operation card

3 CONSTRUCTION PART

4 CONCLUSION

1. INTRODUCTION

The growth of the car park in our country has led to the creation of a car repair production. The need to repair machines arises with their appearance, therefore, human activities aimed at satisfying this need exist as long as there are machines. A well-established repair facility maximizes the life of vehicles. During the downtime of the car for repair, the company suffers losses. It is necessary to bring the car to the line as soon as possible, this is possible only with a quick and high-quality repair. To carry out such repairs, an accurate calculation of the sequence of operations, time and methods of eliminating defects is required.

More and more ATPs are paying great attention to the complex organization of restoration work. With complex restoration, repair time and labor intensity are reduced. Currently, there are many auto repair plants that are engaged in the overhaul of vehicles and their systems and assemblies. This allows to ensure a higher reliability of the car in further operation and the car restored after overhaul is 30-40% cheaper than the cost of a new car, which is very important for ATP. Many parts that are subject to restoration can be repaired can be repaired at an ATP that has special technological equipment, this for the enterprise will cost in a shorter time and in lower material costs.

It is necessary to rely on modern scientific knowledge and have a well-organized engineering service to effectively manage such a large field of activity as auto repair production. The organization of car repairs in our country is constantly paid great attention. Thanks to the development of effective methods for the restoration of worn-out parts, progressive technology of the dismantling and assembly complex of works and the introduction of more advanced technical means in the repair production, prerequisites have been created for increasing the service life of cars after major repairs, although currently the resource of a repaired car is 60-70% of the resource of new cars and the cost of repairs remains high.

2 TECHNOLOGICAL PART

2.2 Operating conditions of the camshaft ZIL - 130

During operation, the camshaft is subjected to: periodic loads from the forces of gas pressure and inertia of the movement of masses, which cause alternating voltage in its elements; friction of the journals on the bearing shells; friction at high specific pressures and loads in the presence of abrasive; dynamic loads; bending and twisting, etc. They are characterized by the following types of wear - oxidative and violation of fatigue strength, molecular-mechanical, corrosion-mechanical and abrasive. They are characterized by the following phenomena - the formation of products of chemical interaction of metals with the environment and the destruction of individual microdistricts of the surface layer with the separation of material; molecular seizure, material transfer, destruction of possible bonds by pulling out particles, etc.

2.3 The choice of rational ways to eliminate defects in the part

The wear of the bearing journals is ground to one of the repair dimensions. Grinding is carried out on a circular grinding machine. Since the simplicity of the technological process and the equipment used; high economic efficiency; maintaining the interchangeability of parts within a certain repair size.

When the thread is worn out, it is eliminated by vibration arc surfacing, since a small heating of the part does not affect their heat treatment, a small heat-affected zone, and a sufficiently high process productivity.

When the eccentric is worn, it is deposited and then grinded on a grinding machine. Since: simple technological process and use of equipment; high economic efficiency; maintaining the interchangeability of parts within a certain repair size.

camshaft car defect

2.4 Development of technological process diagrams, elimination of each defect separately

Table 1

	Parts repair methods	Operation No.	Operations
			Galvanic (iron)
Wear of bearing journals	Ironing		Grinding (grind the neck) Polishing (polish the neck)
			Screw-cutting lathe
Thread wear	Submerged arc surfacing		(cut off worn threads) Screw-cutting lathe (grind, cut threads)
			Surfacing (weld
Worn keyway	Submerged arc surfacing		Screw-cutting lathe (turn) Horizontal milling (mill groove)
			Surfacing
Worn eccentric	Surfacing		(to melt the eccentric) Screw-cutting lathe (turn eccentric) Cylindrical grinding (grinding eccentric)

2.5 Plan of technological operations with the selection of equipment, fixtures and tools

	the name of the operation	Equipment	Gadgets	Tool
	Galvanic (iron)	Iron bath	Iron suspension	Isolation brush	Calipers
	Grinding (grind the necks	Cylindrical grinding machine ZB151	Driving chuck	Grinding wheel L \u003d 450	Micrometer 25-50 mm
	Polishing (polish the necks)
	Screw-cutting lathe (cut thread)
	Surfacing (weld the neck under the thread)
	Screw-cutting lathe (grind, cut a thread)
	Surfacing (weld groove)
	Screw-cutting lathe (turning)
	Milling (milling a groove)
	Surfacing (surfacing exuentric)
	Screw-cutting lathe (grind the eccentric)
	Cylindrical grinding (grind eccentric)

2.6 Brief description of equipment

Screw-cutting lathe 1K62

1 Distances between centers, mm 710, 1000, 1400

2 The largest processing diameter of the bar passing through the spindle, mm 36

Over support - 220

Over bed - 400

3 Spindle revolutions per minute 12.5, 16, 20, 25, 31.5, 40, 50, 63, 80, 100, 125, 160, 200, 250, 315, 400, 500, 630, 800, 1000, 1250, 1600, 2000

4 Longitudinal gears of the support in mm per 1 spindle revolution 0.07, 0.074, 0.084, 0.097, 0.11, 0.12, 0.13, 0.14, 0.15, 0.17, 0.195, 0.21, 0.23, 0.26, 0.28, 0.3, 0.34, 0.39, 1.04, 1.21, 1.4, 1.56, 2.08, 2.42, 2, 8, 3.8, 4.16

5 Cross feeds of the support 0.035, 0.037, 0.042, 0.048, 0.055, 0.065, 0.07, 0.074, 0.084, 0.097, 0.11, 0.12, 0.26, 0.28, 0.3, 1.04, 1.21, 1.04, 2.08, 3.48, 4.16

6 Electric motor power 10 kW

7 Overall dimensions of the machine, mm

length 2522, 2132, 2212

width 1166

height 1324

8 Machine weight 2080-2290 kg

Cylindrical Grinding Machine

1 The largest diameter of the workpiece is 200 mm

2 Grinding wheel diameter, in mm 450-600

3 The greatest travel of the table 780 mm

4 Maximum transverse movement of the grinding wheel headstock 200 mm

5 Maximum length of the grinding piece 7500 mm

6 Power of the main electric motor 7 kW

7 The number of revolutions of the spindle of the grinding wheelhead per minute - 1080-1240

8 Number of revolutions of the headstock spindle per minute 75; 150; 300

9 Limits of speeds of longitudinal motion of a table meters per minute 0/8 $ 10

Horizontal milling machine 6Н82

1 Dimensions of the working surface of the table, in mm 1250х320

2 The greatest movement of the table, in mm

longitudinal - 700

transverse - 250

vertical - 420

3 Number of spindle revolutions per minute - 30; 37.5; 47.5; 60; 75; 95; 118; 150; 190; 235; 300; 375; 475; 600; 750; 950; 1180; 1500

4 Longitudinal and transverse feed, rpm - 19; 23.5; thirty; 37.5; 47.5; 60; 75; 95; 150; 190; 235; 300; 375; 475; 600; 750; 950

5 Vertical feeds are equal to 1/3 of the longitudinal

6 Electric motor power, in kW

reduced spindle - 7

reduced feed - 2.2

7 Machine dimensions, in mm - 2100х1740х1615

8 Machine weight, in kg - 3000

2.7 Selecting installation bases

When the bearing journals are worn, the locating base will be the journal for the timing gear and the gear for the thread.

When the thread is worn out, the support journals will be the locating base.

When the eccentric is worn, the locating base will be the journal for the timing gear and the gear for the thread.

2.8 Calculation of cutting conditions and times

2.8.1 Surfacing

2) weld the tops of the cam;

3) remove the part.

Welding current:

Da - current density (L-1 p. 313 tab. IV 3.3), A / mm2.

Mass of molten metal:

Rpm, (2)

where an is the deposition coefficient (L-1 p. 313 tab. IV 3.3), g / A · h.

, cm3 / min, (3)

where g is the density of the molten metal, taken equal to

density of the molten metal, g / cm3.

cm3 / min.

, m / min, (4)

m / min.

Surfacing speed:

, m / min, (5)

t \u003d 1.5 mm;

S \u003d 0.3 mm / rev.

m / min,

, rpm, (6)

where D is the diameter of the part being welded, mm.

rpm,

, min. (7)

Let's take: \u003d 0.6 min;

\u003d 0.22 min.

min,

, min. (8)

Let's take: L \u003d 0.6927 m;

tv2 \u003d 0.14 min.

min,

, min,

np is the number of warm-ups.

Let's take: F \u003d 18 mm2;

an \u003d 2.5 g / Ah;

r \u003d 7.8 g / cm3;

\u003d 0.1 min;

np \u003d 1.

min,

, min, (9)

min.

2.8.2 Grinding

2) grind the cams;

3) remove the part.

, m / min, (10)

where Cv is a constant depending on the material being processed, the nature of the wheel and the type of grinding;

t - Depth of grinding, mm;

Let's take:

Cv \u003d 0.24 (L1 p. 369 tab. 4.3.92);

b \u003d 0.25;

d \u003d 1.5 mm;

t \u003d 0.05 mm.

m / min.

Determine the speed:

, rpm, (11)

p \u003d 3.14;

S \u003d in B, mm / rev, (12)

circle;

S \u003d 0.25 1700 \u003d 425 mm / rev.

Determine the main time:

tо \u003d i K / n S, min, (13)

S - Longitudinal feed, mm / rev;

(L1 p. 370);

i is the number of passes.

L \u003d l + B, mm, (14)

L \u003d 1.5 + 1700 \u003d 1701.5 mm

, (15)

.

Let's take: S \u003d 0.425 m;

K \u003d 1.4;

i \u003d 1.

min.

Definition of piece time:

tpc \u003d tо + tvu + tvp + torm, min, (16)

where tо is the main time, min;

tvp - auxiliary time associated with the transition, min.

Let's take: tv \u003d 0.25 min;

tvp \u003d 0.25 min.

, min, (17)

, min, (18)

min,

min,

min.

2.8.3 Polishing

1) install the part in the driver chuck;

2) polish the cams;

3) remove the part.

Determine the rotation speed of the workpiece:

, m / min, (19)

where Cv is a constant depending on the material being processed,

the nature of the wheel and the type of grinding;

d - Diameter of the treated surface, mm;

T - Resistance of the grinding wheel, mm;

t - Depth of grinding, mm;

c - Factor determining the proportion of the width of the grinding wheel

k, m, xv, yv - exponents.

Let's take: Cv \u003d 0.24 (L1 page 369 tab. 4.3.92);

k \u003d 0.3 (L1 p. 369 tab. 4.3.92);

m \u003d 0.5 (L1 p. 369 tab. 4.3.92);

xv \u003d 1.0 (L1 p. 369 tab. 4.3.92);

yv \u003d 1.0 (L1 p. 369 tab. 4.3.92);

T \u003d 0.3 min (L1 p. 369 tab. 4.3.92);

b \u003d 0.25;

d \u003d 1.5 mm;

t \u003d 0.05 mm.

m / min.

Determine the speed:

, rpm, (20)

where VД - grinding speed, m / min;

S \u003d in B, mm / rev, (21)

where B is the width of the grinding wheel, mm;

в - coefficient determining the proportion of the width of the grinding

circle.

Let's take: в \u003d 0.50 (L1 page 369 tab. 4.3.90 - 4.3.91);

B \u003d 1700, mm.

S \u003d 0.50 1700 \u003d 850 mm / rev.

Determine the main time:

{!LANG-9e112ed658983157272b339ec7e3d989!}

{!LANG-3b280f2272baebc9fe8876f113f78682!}

{!LANG-68898724ff1612fef1275f0e7be08791!}

S - Longitudinal feed, mm / rev;

{!LANG-6cd9ae4e75368741543b5f675156d93c!}

(L1 p. 370);

i is the number of passes.

{!LANG-07e4ecd97fcc3e648e98b38c43fbcf49!}

{!LANG-48d33f3d116e93fe622385d9398ef096!}

, (24)

.

{!LANG-d883286e98067e32a7d6cc426b4ec30a!}

{!LANG-8f3840a0de58e8c286a49a4fdf2502d8!}

min.

Definition of piece time:

{!LANG-91f92e3e719cbe6fb26ee20b84845b0e!}

where tо is the main time, min;

{!LANG-4d8ce504c9f0da53b75d4869b6d3508c!}

{!LANG-9a4ffbc0b8eae71afbec554f2431911b!}

{!LANG-3e059ec89c3b0c46279ebe517ebaf519!}

{!LANG-7d19c9efcef200d1f507cc0050456587!}

{!LANG-2e02fd51a99a5436188972d3bab1b094!}

min,

min,

min.

2.8.4 Grinding

1) install the part in the driver chuck;

{!LANG-d20949dc452f03daada5a1d8a0c2ed78!}

3) remove the part.

Determine the rotation speed of the workpiece:

{!LANG-a754e97482aec8cedd3c5b2777cec360!}

d - Diameter of the treated surface, mm;

T - Resistance of the grinding wheel, mm;

t - Depth of grinding, mm;

c - Factor determining the proportion of the width of the grinding wheel

{!LANG-b0469d9160a9293a4d93e2260b57831a!}

{!LANG-a1bb8bdafe159ef3f349e5dca183a05b!}

xv \u003d 1.0 (L1 p. 369 tab. 4.3.92);

yv \u003d 1.0 (L1 p. 369 tab. 4.3.92);

{!LANG-74509154ff3c0f1f00b8a7ee78ffddd1!}

b \u003d 0.25;

{!LANG-cd60050335d7135a7f78d98c7b3f50ad!}

t \u003d 0.05 mm.

m / min.

Determine the speed:

{!LANG-702e45017c1c99f7c9ddc3ca9cddad8c!}

where VД - grinding speed, m / min;

p \u003d 3.14;

{!LANG-45220ac5efce6b50c767af11039f83d0!}

{!LANG-47dbe68677ecc75f4ad43ca02dfd7517!}

where B is the width of the grinding wheel, mm;

{!LANG-feebc302dcef1069746c81299db4f8d0!}

S \u003d 0.25 1700 \u003d 425 mm / rev.

Determine the main time:

{!LANG-3616f8045d4c47daa6f667e4d5b52fdb!}

{!LANG-3b280f2272baebc9fe8876f113f78682!}

{!LANG-68898724ff1612fef1275f0e7be08791!}

S - Longitudinal feed, mm / rev;

{!LANG-6cd9ae4e75368741543b5f675156d93c!}

(L1 p. 370);

i is the number of passes.

{!LANG-441152787e0fa1af2fd32b891495ed2e!}

{!LANG-21471565ab067d892425a0a16c0847b7!}

, (33)

.

Let's take: S \u003d 0.425 m;

{!LANG-8f3840a0de58e8c286a49a4fdf2502d8!}

min.

Definition of piece time:

{!LANG-c33f71be6dd842892d87fa02e3057237!}

where tо is the main time, min;

{!LANG-4d8ce504c9f0da53b75d4869b6d3508c!}

{!LANG-075a5cb5c42b1032dc461c9c71588322!}

{!LANG-9a4ffbc0b8eae71afbec554f2431911b!}

{!LANG-3e059ec89c3b0c46279ebe517ebaf519!}

{!LANG-459d4ba3ab3276392e0004d79d9e2e5d!}

{!LANG-b586841cacf75394d51e5822f5f540b4!}

min,

min,

min.

2.8.5 Surfacing

{!LANG-ce8ae7ecda5c134e54e5330d8664696a!}

{!LANG-785db107915b4bbc657656fdb31d88cd!}

3) remove the part.

Welding current:

{!LANG-078f8f8dbef57a123e2943831d514fa8!}

{!LANG-e806ff41059215b929822e837fcbd7e9!}

{!LANG-b07d5225e2fcd02f6142a28034450f88!}

{!LANG-45288a7a30db7718a9dc2265601b9aaf!}

{!LANG-9810ad7cfcf723f119f1de0d7d5cba6d!}

Mass of molten metal:

{!LANG-b8d13200ee4192eb7fd1f1b07c28bbed!}

{!LANG-b0fdcc241544b7629c7e9af880f65e35!}

{!LANG-90879dec39c78848368261fe822eacd7!}

{!LANG-271e44c82a3fd36a3f0c090aabe6d464!}

cm3 / min.

{!LANG-b23b71bdc3d4decfd55bceb02ed6c269!}

{!LANG-32f3e105b49fadb10b2359f3176bd3ae!}

{!LANG-0936abad9d1b7526feb065f074ef958f!}

{!LANG-e305a7cdd043d89dfc044dfa3a8c9f6a!}

m / min.

Surfacing speed:

{!LANG-b6405bf232e22d1acd5580dabe6440e1!}

{!LANG-09b06cd57f2b8cebd7a46c6e479d5080!}

{!LANG-15164d5183f8c9115c403cfa4f80a9e1!}

t \u003d 1.5 mm;

S \u003d 0.3 mm / rev.

m / min.

{!LANG-7b49516269257866c4900deae30ae1ac!} :

{!LANG-0b6cc1ec245264747c138e1fab386ec6!}

rpm,

{!LANG-00f820ea9de34764463a4e04bfcef1cf!}

Let's take: \u003d 0.6 min;

\u003d 0.22 min.

min,

{!LANG-b7711c2ebeffb4bee29c53857407baef!}

Let's take: L \u003d 0.6927 m;

tv2 \u003d 0.14 min.

min,

{!LANG-108c7db1bb0f45024269a92c464e438d!}

{!LANG-0cbd084d62a02d95be6801cdf4461726!}

{!LANG-c00172ba2725bec9a251efdceb1b681d!}

{!LANG-bdf7265d4ea2438566d29b97f1fcc4f0!}

{!LANG-e84edefa166b3696a1c123fc18b21fa4!}

np is the number of warm-ups.

Let's take: F \u003d 18 mm2;

an \u003d 2.5 g / Ah;

r \u003d 7.8 g / cm3;

\u003d 0.1 min;

np \u003d 1.

min,

{!LANG-f5fd108ca13a1c388facb3053f2af9dd!}

min.

{!LANG-c9f1729ce5f0f776c584b88e2302ad1b!}

1) install the part in the driver chuck;

{!LANG-45c5e351d4a0f722549aa8fbb55cc3ec!}

3) remove the part.

Determine the rotation speed of the workpiece:

{!LANG-94e2c79b2a4f436e76d477c34ca94e5f!}

{!LANG-00427535f49b94a0abee1594bbfbcc73!}

d - Diameter of the treated surface, mm;

T - Resistance of the grinding wheel, mm;

t - Depth of grinding, mm;

c - Factor determining the proportion of the width of the grinding wheel

{!LANG-313dd301cc49166e936c6dc73707b1b1!}

{!LANG-b0469d9160a9293a4d93e2260b57831a!}

m \u003d 0.5 (L1 p. 369 tab. 4.3.92);

xv \u003d 1.0 (L1 p. 369 tab. 4.3.92);

yv \u003d 1.0 (L1 p. 369 tab. 4.3.92);

T \u003d 0.3 min (L1 p. 369 tab. 4.3.92);

b \u003d 0.25;

{!LANG-cd60050335d7135a7f78d98c7b3f50ad!}

t \u003d 0.05 mm.

m / min.

Determine the speed:

{!LANG-22ea5e9bb5cd33dd4ec5ed792993d5f6!}

where VД - grinding speed, m / min;

p \u003d 3.14;

{!LANG-4851a7e786dded3649d58b51f5f81667!}

{!LANG-82d991b11e33105849a2fc769e33db9a!}

where B is the width of the grinding wheel, mm;

{!LANG-9b59a11097d882236bd746effc883e06!}

{!LANG-feebc302dcef1069746c81299db4f8d0!}

S \u003d 0.25 1700 \u003d 425 mm / rev.

Determine the main time:

{!LANG-8152746c44b230ebd5607a6322c2b02e!}

{!LANG-3b280f2272baebc9fe8876f113f78682!}

{!LANG-68898724ff1612fef1275f0e7be08791!}

S - Longitudinal feed, mm / rev;

{!LANG-6cd9ae4e75368741543b5f675156d93c!}

(L1 p. 370);

i is the number of passes.

{!LANG-2ab41e3b7b4af828530691b5f81b1599!}

{!LANG-9a7b801c1d62c22cd237e8c291e92bd2!}

, (51)

.

Let's take: S \u003d 0.425 m;

{!LANG-8f3840a0de58e8c286a49a4fdf2502d8!}

min.

Definition of piece time:

{!LANG-7865312a21b7cf7978c2e09c90fcb78b!}

where tо is the main time, min;

{!LANG-4d8ce504c9f0da53b75d4869b6d3508c!}

{!LANG-075a5cb5c42b1032dc461c9c71588322!}

{!LANG-ce0697cd1a92bdea35224a2f297231d5!}

tvp \u003d 0.25 min.

{!LANG-cb97c483cb0d57e04db841d784ab01c1!}

{!LANG-d3cdb395891d1b7f0da27ae03634efb7!}

min,

min,

min.

2.8.7 Turning

1) install the part in the driver chuck;

{!LANG-7642a365b20bded9a7a5459c2b4ee91d!}

3) remove the part.

{!LANG-5c04b326a0a5676971ae5a842a71ede8!}

{!LANG-401a64a20340ae34f5826a163f88118f!}

:

{!LANG-79344dd7ffacf0092d7e573b057d0750!}

{!LANG-832b404ef8d27363748946ac8a80e573!}

{!LANG-e97e4c603dbc712f1e118666d1491fb7!}

{!LANG-ab820c73dd64142dac629a9ff4e34e6d!}

{!LANG-86ef48bb8ad58f21d31b3d3140c0408d!}

{!LANG-25008b37f68c85a3d4a92379f4406bd2!}

{!LANG-7bd1a90f99bc126db815376a56d1bcbe!}

{!LANG-d2969ed6d3810e933484b189930898e8!}

{!LANG-1bad9ae867ff02642a559d91f24b6372!}

{!LANG-0896df49ccffe504a56451f43d0d8bcb!}

{!LANG-105045e90b883ee7952533dd3f75c9ff!}

{!LANG-2feb4af49537195618dd462f30a16d2b!}

{!LANG-ba2fb8356e64417cbb7af13ed6eb41f7!}

{!LANG-9442380825ad0db0d39d9fc48001de39!}

min.

Definition of piece time:

{!LANG-41be71aa56f069acbc0ada283fb5d194!}

where tо is the main time, min;

{!LANG-4d8ce504c9f0da53b75d4869b6d3508c!}

{!LANG-075a5cb5c42b1032dc461c9c71588322!}

{!LANG-d5be0ce9ce107fddf1cbafe205d7a1aa!}

{!LANG-eb88e3aecf8a75fdee5fb771c26e9222!}

min,

min,

min.

2.8.8 Surfacing

{!LANG-4878e2dee1aea7cc372ebb8abbd770dd!}

{!LANG-c3766f2c6ca63f385c8e692c28c9773a!}

3) remove the part.

Welding current:

{!LANG-037eb8da0ec34fac3c24d3f858c4d425!}

{!LANG-e806ff41059215b929822e837fcbd7e9!}

{!LANG-15536f76715856b55d5c83aa89c250b3!}

d \u003d 1.5 mm;

{!LANG-65ce67ef96f72510e9621e92bcc50ea5!}

{!LANG-9810ad7cfcf723f119f1de0d7d5cba6d!}

Mass of molten metal:

{!LANG-7c44d20e6e4cd580faa29ac9e4e1a337!}

{!LANG-b3fac0916762d6f19cf6f01041d3acf2!}

{!LANG-b0fdcc241544b7629c7e9af880f65e35!}

{!LANG-90879dec39c78848368261fe822eacd7!}

{!LANG-dcdddaf92cf807f4e62067bf4c1923d3!}

{!LANG-deed0b20a8312021b0fcc81870fcdb78!}

{!LANG-e4740d2612f7d792691c1d1f1f4fe9c4!}

cm3 / min.

{!LANG-0936abad9d1b7526feb065f074ef958f!}

{!LANG-2e16a3fc2c244bd5e302969bf70b0744!}

m / min.

Surfacing speed:

{!LANG-d3f12567c8ce31c8bdce68d8dc793dc2!}

{!LANG-09b06cd57f2b8cebd7a46c6e479d5080!}

{!LANG-15164d5183f8c9115c403cfa4f80a9e1!}

t \u003d 1.5 mm;

S \u003d 0.3 mm / rev.

m / min,

{!LANG-611351ec7212145c3cce59bb9ed2f0b6!}

{!LANG-200381bea79bf38908650eeede120471!}

rpm,

{!LANG-92bc2754ae74f233fb51144307dbfd1c!}

Let's take: \u003d 0.6 min;

\u003d 0.22 min.

, min,

{!LANG-1e624a3bcca1f23947c4aacc67944d50!}

Let's take: L \u003d 0.6927 m;

tv2 \u003d 0.14 min.

min,

{!LANG-108c7db1bb0f45024269a92c464e438d!}

{!LANG-0cbd084d62a02d95be6801cdf4461726!}

{!LANG-c00172ba2725bec9a251efdceb1b681d!}

{!LANG-74d381c20c1db7c2dc67043ac5c97e99!}

{!LANG-498e49119788cc804126162bfdaf093c!}

{!LANG-e84edefa166b3696a1c123fc18b21fa4!}

np is the number of warm-ups.

Let's take: F \u003d 18 mm2;

{!LANG-a61c976c1c65ab579700d6d7503a7f33!}

r \u003d 7.8 g / cm3;

\u003d 0.1 min;

np \u003d 1.

min,

{!LANG-0e4d94a8b829ad2f64d37acd366a7727!}

min.

2.8.9 Turning operation

1) install the part in the driver chuck;

{!LANG-5e6a45711bfe6cb5f527998fcd2bf73e!}

3) remove the part.

{!LANG-5c04b326a0a5676971ae5a842a71ede8!}

{!LANG-36efdbcbdfc5021207b4dcf2a79781fe!}

{!LANG-4bdbff3ab35b0da0311c2f2ec9558ff9!}

{!LANG-d5542b441ea3c17e48ef9c55298f10fe!}

{!LANG-86d0f0bacf298099907de9390572f5fb!}

{!LANG-ba48d7863be80a9ea7232e0d52ce7c51!}

{!LANG-582553e9165872b53fcb701a514b5457!}

{!LANG-4fa7c76ca00ee972acb59c8902fb6f7d!}

{!LANG-b3863e0cf80d5c1ba7ee310c0ad6985e!}

{!LANG-832b404ef8d27363748946ac8a80e573!}

{!LANG-e97e4c603dbc712f1e118666d1491fb7!}

{!LANG-ab820c73dd64142dac629a9ff4e34e6d!}

{!LANG-858649cc72b945115742e336fe49a894!}

{!LANG-8243309ba121f9df1e7af07ccbf5bfd7!}

{!LANG-7fedb85ad2d0e12704b7821dbb61faed!}

{!LANG-25008b37f68c85a3d4a92379f4406bd2!}

{!LANG-7b9d495a2b598c752d05ee1e618c1656!}

{!LANG-5b1e859c6f705ebb406ffa0a9011f235!}

{!LANG-5b8683f450919040159a087a51c1773f!}

{!LANG-b3d7215016f9d7d3301cb353e50368f5!}

{!LANG-7cbeed3754a887cdacc4455a1711714a!}

{!LANG-fc130a3624e11ddc837d738c915d4388!}

{!LANG-1bad9ae867ff02642a559d91f24b6372!}

{!LANG-0896df49ccffe504a56451f43d0d8bcb!}

{!LANG-4a8dab02697129f33034ee5ac2b9b358!}

{!LANG-88311f03be3719de87faed8964fb20a0!}

{!LANG-2feb4af49537195618dd462f30a16d2b!}

{!LANG-584a8a26c777fe86ead23a1e408b6633!}

{!LANG-e184212cf13b198efc0713518b15027d!}

{!LANG-399f4a672613d4665e12afee3dd1b32f!}

{!LANG-4cf87a550aabcf1acfc3b6b8ede3fbda!}

{!LANG-9442380825ad0db0d39d9fc48001de39!}

{!LANG-bef5f0f505dec1f31b5e8382aea48a93!}

{!LANG-d8ed81151a98ae1bf5a6fb7f2f6197b2!}

{!LANG-e25756365d14932ba5cc00ee53e9749b!}

min.

Definition of piece time:

{!LANG-e74ba9421e677062f2399fcabac252f5!}

where tо is the main time, min;

{!LANG-4d8ce504c9f0da53b75d4869b6d3508c!}

{!LANG-075a5cb5c42b1032dc461c9c71588322!}

{!LANG-fff091c1e10df49de3dacade78c3e5f5!}

{!LANG-5090dc1b4ad5a2c8508940d3340377a1!}

{!LANG-277a29b6642aad8aae7e1fdce9c89b38!}

{!LANG-4794415dab035656a66565a44247695c!}

min,

min,

min.

2.8.10 Milling

{!LANG-7537f3e89e6907e880f9ce96dc3a616f!}

{!LANG-809dee9d8c5582b23d500f07b9461988!}

3) remove the part.

{!LANG-95c89f079cca710621ed596bc2b42fe6!}

{!LANG-7f756311b74737f4ecc5f76bf651d8df!}

{!LANG-912fec39bc991793d4a81ca86cec4dc6!}

{!LANG-875a9088422269f80334e612ebf8382d!}

{!LANG-661073fc3143fa699deaafbdecff2560!}

{!LANG-7f4782706bd883a561015116c2b09e5c!}

{!LANG-bd9422964ba94e7ffd2d18615ec65cec!}

{!LANG-832b404ef8d27363748946ac8a80e573!}

{!LANG-832b404ef8d27363748946ac8a80e573!}

{!LANG-acea88620d14d1b4be680150be80e173!}

{!LANG-c0c5ded3dfb632aa26b95270891a66b8!}

{!LANG-9acdf69b9c5166fa76fbf1fee76a646d!}

{!LANG-97aebb6b000d1dc509f4696b367873cb!}

{!LANG-ab156e12cfa5bd990ff8a32752c5c534!}

{!LANG-505dac654ad37ff55fdca88e5db8bf0d!}

{!LANG-07612bde395c56981974dfb9e544410e!}

{!LANG-333627415d027ceef0f50ca9aa16e7dd!}

{!LANG-a5b9d624751c80940438dc4ff0308052!}

{!LANG-3919b9b8623fc10eb90242e3fa3f092a!}

{!LANG-e7009cbd36534036ad465ff40955c2a9!}

{!LANG-cf5b8a63178087d4fb2521a801516d89!}

{!LANG-cdab04c62dd555536e75e7ceee4d97cb!}

{!LANG-1bad9ae867ff02642a559d91f24b6372!}

{!LANG-e8488ef0320083424a2ff22ae4c6c50d!}

{!LANG-cf87dc4ee64f34a34dd276c25f9211c1!}

{!LANG-2feb4af49537195618dd462f30a16d2b!}

{!LANG-7b9f47ab00ff94f28c6f8865ac2b9f06!}

{!LANG-44ee9c173939317817e086400937a410!}

{!LANG-088d603d3afa8d088822f341da2ffa62!}

{!LANG-e124346c80fe61d1c78dedae1511bc32!}

{!LANG-9badd730e7ee10a0b6d50a68e52e8766!}

{!LANG-1bad9ae867ff02642a559d91f24b6372!}

{!LANG-3ca6e67a7cfd15be29ea229349c69d21!}

{!LANG-a4eac527113d2f74d0e3a577a1842f0b!}

{!LANG-c989f9269c69a00108e0d0ed0bcb1a9b!}

{!LANG-9657c0457d275afea53c21cae048ab35!}

{!LANG-74d9f7adbcb77b5759cd092cc47225e6!}

{!LANG-b72d9bf08d4dcab83220221792c89b9c!}

{!LANG-4f4b2deb16471ec7ac62d6bf24b6cbc7!}

i \u003d 1.

min.

Definition of piece time:

{!LANG-17a9cd65154318f4edb4131bc2da6ca9!}

where tо is the main time, min;

{!LANG-4d8ce504c9f0da53b75d4869b6d3508c!}

{!LANG-075a5cb5c42b1032dc461c9c71588322!}

{!LANG-fff091c1e10df49de3dacade78c3e5f5!}

{!LANG-5090dc1b4ad5a2c8508940d3340377a1!}

{!LANG-96d9b65063405cda551532c7e1a8f19b!}

{!LANG-9d674570a518cd957ae19d0f69178164!}

min,

min,

min.

{!LANG-ceb34a44fbd0a53ed5c3ed0abede44b7!}

{!LANG-efa897358c73b6de8573df745656972e!}

{!LANG-7c1299318b58286e95944f26d1002cae!}

3) remove the part.

Definition of piece time:

{!LANG-6cbfa5db5add07a41bf4007a80cae014!}

{!LANG-15fc504ac3cf805d152b5e2a2beb343a!}

{!LANG-0818a9f6b1ac2577d0a6f68bcca902cb!}

{!LANG-7347935d0eed0e02a101c4cfbf5dda18!}

{!LANG-b678c93e0538b90c8f96ef0f30c094ff!}

{!LANG-909ccf8d2154aabd19a0333a512e2321!}

{!LANG-832b404ef8d27363748946ac8a80e573!}

min,

, min,

, min,

, min,

min,

min,

min,

min.

{!LANG-e2a0f4b4fc4572cfafc196a62307e26b!}

{!LANG-234031185337070ff821b23fa6a5776d!}

{!LANG-2108a8f4d597d7ed5c1014dc7b80e841!}

{!LANG-ce2cafe1f77be8c6629aff815be263b7!}

{!LANG-78f4526f59b4b6e5ca9dc21a710b5a7d!}

{!LANG-104e1a54162b4cd6fb65c72f4c488ec7!}

{!LANG-783d656fb46e8132c607a7360dc4a0ec!}

{!LANG-03d4c8ec1de3d1a71d9023c95d1f6bfa!}

{!LANG-d80ccd7504913b2d9b799c4199bcd0da!}

{!LANG-e1676bd7f60f5b37b9bc16ba034220b0!}

{!LANG-7b2779269143f063a62294cf48d2d538!}

.

2.9.1 Surfacing

min.

2.9.2 Grinding

min.

2.9.3 Polishing

min.

2.9.4 Grinding

min.

2.9.5 Surfacing

min.

2.9.6 Grinding

min.

2.9.7 Turning

min.

2.9.8 Surfacing

min.

2.9.9 Turning

min.

2.9.10 Milling

min.

{!LANG-6973e943b1e86ecb6577a48919e8ee78!}

min.

2.10 Operation card

{!LANG-028df4490b45cc1e1851046028f3faf0!}

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Surfacing {!LANG-bc41740deea26049fc0fa051e0515b4e!} {!LANG-fe8e30b0566b06d7d7a410154b06483e!} {!LANG-dd777138f7b430b93e864651a9941e0b!}		Calipers
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3 CONSTRUCTION PART

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4 CONCLUSION

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