What's the general level exam for junior car turners?

The examination is divided into written examination and practical operation.

The specific requirements are as follows:

I. Knowledge requirements

1. Name, model, specification, performance, structure and transmission system of self-use equipment.

2. Lubrication system, usage rules and maintenance methods of self-use equipment.

3 common tools, fixtures, measuring tools (instruments) name, specifications, uses, rules of use and maintenance methods.

4. Types, brands, specifications and performance of commonly used tools; Influence of tool geometry parameters on cutting performance.

5. Types, brands, mechanical properties, cutting properties and knowledge of thermal expansion during cutting of commonly used metal materials.

6. Types and uses of commonly used lubricating oils.

7. Types and uses of common cutting fluids and their effects on surface roughness.

8. Basic knowledge of mechanical drawing, tolerance fit, form and position tolerance and surface roughness.

9. Basic knowledge of mechanical transmission.

10. Basic knowledge of locksmith.

1 1. General process knowledge of related work.

12. Common knowledge of mathematical calculation.

13. Basic knowledge of cutting parameters. Basic principles of selecting cutting parameters.

14. the processing method of stepped shaft and the method to meet the requirements of coaxiality.

15. General nesting processing methods and methods to meet technical requirements.

16. Standard, calculation and turning method of common cones.

17. Types and uses of common threads, calculation methods of main dimensions (including consulting relevant thread tables) and calculation, selection and turning methods of exchanging gears when turning threads.

18. Types and structures of spring chuck, feeding mechanism, tap and self-opening die.

19. Basic knowledge of heat treatment of front axle, hole machining allowance and grinding allowance.

20. Common knowledge of metal heat treatment.

2 1. Common knowledge of self-use equipment and electrical appliances, and knowledge of safe electricity use.

22. Analyze the causes of waste products and preventive measures.

23. Safety technical regulations.

Second, the skill requirements:

1. Operate and maintain self-use equipment, and find common faults in time.

2. Use common tools, fixtures and measuring tools and be able to maintain them.

3. According to the workpiece materials and processing requirements, reasonably select, use and sharpen various commonly used turning tools and drills.

4. Reasonable selection of cutting parameters.

5. Understand the part drawings and correctly implement the process regulations.

6. Correct use of universal fixture and combined fixture.

7. Turning commonly used inner and outer conical surfaces.

8. Turning a workpiece with a simple forming surface.

9. Turning of internal and external triangular threads with general accuracy and shorter rectangular and trapezoidal threads.

10. Processing and measurement of general parts.

1 1. Basic operation skills of locksmith.

12. Correctly implement safety technical operation procedures.

13. It meets the requirements of post responsibility system and civilized production.

Third, the work example:

1. Lathe step shaft (grade 3 ~ 4), coaxiality tolerance of 0.05mm, surface roughness Ra of 3.2mm. ..

2. Turn the duplex gear on the horizontal lathe or turret lathe. The tolerance level of the inner hole is IT7, the coaxiality tolerance is 0.05mm, and the surface roughness of the inner hole is Ra 3.2 mm ..

3. The elliptical or three-ball handle machined by lathe is allowed to be polished with emery cloth, and the shape meets the requirements, and the surface roughness is Ra1.6mm. ..

4. Machine-made M24 bolt, with a length of 300mm and a certain accuracy, has a surface roughness of Ra3.2mm, and has passed the inspection with thread ring gauges.

5. Turn the small sliding screw of CA6 140 lathe and check it with thread ring gauge. The surface roughness is ra1.6mm. ..

6. Turn the disc and wheel parts with outer diameter ≤f 1500mm and inner hole ≤f 120mm on the vertical lathe. The tolerance level is IT8, and the perpendicularity between the two end faces and the hole axis is 0. 08 mm, and the surface roughness is ra 3.2 mm.