Technical requirements and standards for metal plates

Complete sheet metal technical requirements:

1. Remove scale from sheet metal parts.

2. On the machined surface of sheet metal parts, there should be no scratches, scratches and other defects that damage the surface of the parts.

3. Remove burrs and flash.

4. after conditioning, it is 28 HRC ~ 32 HRC.

5. High frequency quenching of sheet metal parts, tempering at 350 ~ 370℃ for 40HRC~45HRC.

6. The carburizing depth is 0.3mm.

7. Carry out high-temperature aging treatment.

8. Unmarked shape tolerances shall comply with GB 1 184-2000.

9. Unmarked dimensional tolerance shall comply with GB/T1804-M..

10. The tolerance zone of the casting is symmetrical with the basic size configuration of the blank casting.

1 1. Unregistered fillet radius R5.

12. All unmarked chamfers are 2× 45.

13. The acute angle is blunt.

14. Before assembly, all seals must be saturated with oil.

15. When assembling rolling bearings, it is allowed to heat them with oil, and the oil temperature shall not exceed 100℃.

16. After the gear is assembled, the tooth surface contact point and backlash shall comply with the provisions of GB 10095 and GB 1 1365.

17. When assembling the hydraulic system, it is allowed to use sealing filler or sealant, but it should be prevented from entering the system.

18. Parts (including purchased parts and outsourced parts) entering assembly must be certified by the inspection department before assembly.

19. Parts must be cleaned before assembly, and there must be no burr, flash, scale, rust, debris, oil stain, colorant and dust.

20. Before assembly, check the main fit dimensions of parts, especially the interference fit dimensions and related accuracy.

2 1. During assembly, parts are not allowed to be knocked, collided, scratched and rusted.

22. When fastening screws, bolts and nuts, it is forbidden to knock or use inappropriate screwdrivers and wrenches. Screw grooves, nuts, screws and bolt heads shall not be damaged after fastening.

23. Fasteners with specified tightening torque requirements must be tightened with a torque wrench.

24. When multiple screws (bolts) are used to fasten the same part, the screws (bolts) should be tightened crosswise, symmetrically, step by step and evenly.

25. Taper pins should be coated with holes during assembly, and the contact rate should not be less than 60% of the mating length, and should be evenly distributed.

26. Ping Jian should be in uniform contact with both sides of the keyway on the shaft, and there should be no gap between the mating surfaces.

27. The number of tooth surfaces contacted by spline assembly at the same time should not be less than 2/3, and the contact rate in the length and height direction of key teeth should not be less than 50%.

28. After assembling Ping Jian (or spline) with sliding fit, the fittings can move freely without uneven tightness.

29. After bonding, the excess adhesive flowing out shall be removed.

30. The bearing outer ring and the semi-circular hole of the open bearing seat and bearing cover are not allowed to get stuck.

3 1. The bearing outer ring should be in good contact with the semicircular holes of the open bearing seat and bearing cover. During coloring inspection, the bearing outer ring should be in uniform contact with the bearing seat within the range of120 and 90 symmetrical to the center line. When checking with a feeler gauge within the above range, a feeler gauge of 0.03mm shall not be inserted into 1/3 of the outer ring width.

32. After the bearing outer ring is assembled, it should be in uniform contact with the end face of the bearing cover at the positioning end.

33. After the rolling bearing is installed, it should be flexible and smooth to rotate by hand.

34. The joint surface of the upper and lower bearing shells should be closely fitted, and cannot be checked with a feeler gauge of 0.05mm..

35. When fixing the bearing bush with the locating pin, the hinge and pin should be drilled and matched under the condition that the opening and closing surfaces and end faces of the bearing hole are flush with the end bread. The pin must not be loose after driving.

36. The bearing body and bearing seat of spherical bearing should be in uniform contact, and the contact should be not less than 70% by coloring method.

37. Alloy bearing liner surface Huang Shi is not allowed to be used, and it is not allowed to leave the core within the specified contact angle. The nucleation area beyond the contact angle shall not be greater than 10% of the total area of the non-contact area.

38. The reference end face of the gear (worm wheel) and the shaft shoulder (or the end face of the positioning sleeve) should be matched together, and cannot be checked with a feeler gauge of 0.05mm.. And should ensure the verticality of gear reference end face and axis.

39. The joint surface of gear box and cover should be in good contact.

40. Before assembly, strictly check and remove sharp corners, burrs and foreign bodies left in the process of machining parts. Ensure that the seal will not be scratched when loading.

4 1. Cold insulation, cracks, shrinkage cavities, penetration defects and serious incomplete defects (such as insufficient casting, mechanical damage, etc.). ) are not allowed to appear on the casting surface.

42. Castings should be clean without burrs and flash, and gates and risers on non-machining instructions should be clean to be flush with the surface of castings.

43. The casting characters and signs on the non-machined surface of the casting should be clearly identifiable, and the position and font should meet the requirements of the drawings.

44. The roughness (sand casting R) of the unprocessed surface of the casting shall not exceed 50μ m. ..

45. Castings should be cleared of gates, risers and flying thorns. The remaining gates and risers on the unprocessed surface should be leveled and polished to meet the surface quality requirements.

46. The molding sand, core sand and core bone on the casting should be removed.

47. The casting has an inclined part, and its size tolerance zone should be symmetrically configured along the inclined surface.

48. Molding sand, core sand, core bone, meat and sticky sand on castings should be shoveled off and cleaned up.

49. Dislocation, boss casting deviation, etc. Correction should be made to achieve a smooth transition and ensure the appearance quality.

50. The wrinkle depth on the non-machined surface of the casting should be less than 2mm, and the spacing should be greater than 100 mm. ..

5 1. The unmachined surface of machine metal plate castings needs shot peening or roller treatment to meet the requirements of Sa2 1/2 cleanliness.

52. Castings must be toughened by water.

53. The casting surface should be smooth, and the sprue, burr and sand adhesion should be removed.

54. Casting defects that are not conducive to use, such as cold insulation, cracks and holes, are not allowed.

55. Before painting, rust, scale, grease, dust, soil, salt and dirt on the surface of all steel parts that need painting must be removed.

56. Before derusting, use organic solvent, lye, emulsifier and steam to remove grease and dirt on the surface of steel parts.

57. The interval between the shot-blasted or manually derusted surface and the primer shall not exceed 6h.

58. Before connection, the surfaces of riveted parts in contact with each other must be coated with 30 ~ 40μ m thick antirust paint. Lap edges shall be sealed with paint, putty or adhesive. Primer damaged by machining or welding shall be repainted.

59. Before assembly, all pipes shall be deburred and chamfered. Use compressed air or other methods to remove impurities and floating rust attached to the inner wall of the pipeline.

60. Before assembly, all steel pipes (including prefabricated pipes) should be degreased, pickled, neutralized, cleaned and rustproof.

6 1. When assembling, the parts fixed with threads such as pipe clamps, brackets, flanges and joints should be tightened to prevent looseness.

62. The welded parts of prefabricated pipes shall be subjected to pressure test.

63. When replacing or transferring the pipeline, the pipeline separation port must be sealed with adhesive tape or plastic pipe to prevent any sundries from entering, and a label must be attached.

64. Defects must be completely removed before repair welding, and the groove surface should be smooth and level without sharp corners.

65. According to the defects of steel castings, the defects in the repair welding area can be removed by shoveling, grinding, carbon arc gouging, gas cutting or machining.

66. The dirt such as sand, oil, water and rust within 20 mm around the repair welding area and groove must be thoroughly cleaned up.

67. In the whole repair welding process, the temperature in the preheating zone of steel castings shall not be lower than 350℃. ..

68. When conditions permit, weld in a horizontal position as far as possible.

69. When repairing welding, covered electrode should not make a big lateral swing.

70. When the surface of steel castings is stacked for welding, the lap joint between weld beads shall not be less than 1/3 of the weld bead width.

7 1. The nozzle and riser of each ingot should have enough cutting capacity to ensure that the forging has no shrinkage cavity and serious deflection.

72. Metal plate forgings should be forged on a forging press with sufficient capacity to ensure full forging inside the forgings.

73. Sheet metal forgings are not allowed to have visible cracks, folding and other appearance defects that affect the use. Local defects can be removed, but the depth of removal shall not exceed 75% of the machining allowance, and the defects on the non-machined surface of forgings shall be cleaned and transferred smoothly.

74. Sheet metal forgings are not allowed to have white spots, internal cracks and residual shrinkage cavities.

75. Finished parts shall not be placed directly on the ground, and necessary support and protection measures shall be taken. No rust, bumps, scratches and other defects affecting performance, service life or appearance are allowed on the machined surface.

76. The surface of the rolling processing, can not have peeling phenomenon after rolling.

77. There should be no scale on the surface of sheet metal parts after heat treatment in the final process. After finishing, the mating surface and tooth surface should not be annealed.

78. The processed thread surface is not allowed to have defects such as black skin, bulge, bending and burr.

79, blue, discoloration phenomenon.