Mechanical and electrical technical requirements

1. Remove oxide scale of parts.
2. There should be no scratch, scratch and other defects on the surface of parts.
3. Remove burr and flash.
4. After quenching and tempering, HRC50 ~ 55.
5. High frequency quenching, tempering at 350-370 ℃, hrc40-45.
6. Carburizing depth is 0.3mm.
7. High temperature aging treatment.
8. Undeclared shape tolerance shall meet the requirements of gb1184-80.
9. The allowable deviation of unmarked length is ± 0.5mm.
10. The tolerance zone of casting is symmetrical to the basic dimension configuration of blank casting.
11. The fillet radius R5 is not noted.
12. The undeclared chamfer is 2 × 45 °.
13. Blunt the acute angle.
14. All seals must be soaked in oil before assembly.
15. It is allowed to heat the rolling bearing with oil, and the oil temperature shall not exceed 100 ℃.
20. After the gear is assembled, the contact spot and side clearance of the tooth surface shall comply with the provisions of GB10095 and gb11365.
21. When assembling the hydraulic system, it is allowed to use sealing filler or sealant, but it should be prevented from entering the system.
22. The parts and components (including purchased parts and outsourcing parts) entering the assembly must have the certificate of inspection department before they can be assembled.
23. The parts must be cleaned and cleaned before assembly, without burr, flash, oxide scale, rust, chip, oil stain, colorant and dust.
24. Before assembly, the main matching dimensions of parts and components, especially the interference fit size and relevant accuracy shall be rechecked.
25. Parts are not allowed to knock, bump, scratch and rust during assembly.
26. When the screws, bolts and nuts are tightened, it is strictly forbidden to hit or use improper screwdrivers and spanners. After fastening, the screw groove, nut, screw and bolt head shall not be damaged.
27. The fasteners with specified tightening torque requirements must use torque wrench and be tightened according to the specified tightening torque.
28. When the same part is fastened with multiple screws (bolts), the screws (bolts) shall be tightened alternately, symmetrically, gradually and evenly.
29. The taper pin shall be painted with the hole during assembly, and its contact rate shall not be less than 60% of the matching length, and shall be evenly distributed.
30. The flat key and the two sides of the keyway on the shaft shall be in uniform contact, and there shall be no gap on the mating surface.
31. The number of tooth surfaces contacted at the same time by spline assembly shall not be less than 2 / 3, and the contact rate shall not be less than 50% along the length and height of key teeth.
32. After the sliding fit flat key (or spline) is assembled, the parts can move freely without uneven tightness.
33. Excess adhesive should be removed after bonding.
34. The semicircular hole of bearing outer ring, open bearing seat and bearing cover shall not be stuck.
35. The outer ring of the bearing shall be in good contact with the semicircular hole of the open bearing seat and the bearing cover. During the color coating inspection, the bearing cup shall be in the range of 120 ° symmetrical to the center line of the bearing seat and 90 ° to the center line of the bearing cover
Uniform contact within the enclosure. When the feeler gauge is used for inspection within the above range, the 0.03mm feeler gauge shall not be inserted into 1 / 3 of the outer ring width.
36. After assembly, the bearing outer ring should be in even contact with the end face of the locating end bearing cover.
37. After the rolling bearing is installed, it should rotate flexibly and stably by hand.
38. The joint surface of the upper and lower bearing shells should be close to each other and cannot be checked with a 0.05mm feeler gauge.
39. When fixing bearing bush with locating pin, reaming and pin distribution shall be carried out under the condition that the bearing mouth surface and end face are level with the opening and closing surface and end face package of relevant bearing holes. The pin shall not be loose after being driven in.
40. The bearing body and bearing seat of spherical bearing shall be in uniform contact, and the contact shall not be less than 70% by color coating method.
41. When the surface of alloy bearing liner is yellow, it is not allowed to use, and there is no nucleation phenomenon within the specified contact angle. The area outside the contact angle shall not be greater than 10% of the total area of non-contact area.
42. The reference end face of the gear (worm gear) should fit with the shaft shoulder (or the end face of the locating sleeve), and can not be checked with a 0.05mm feeler gauge. The perpendicularity requirements between the gear reference end face and the axis shall be ensured.
43. The joint surface of gearbox and cover shall be in good contact.
44. Before assembly, strictly check and remove the sharp corners, burrs and foreign matters left in the machining of parts. Ensure that the seal will not be scratched during installation.
45. No cold shut, crack, shrinkage cavity, penetrating defect and serious defect (such as under casting, mechanical damage, etc.) are allowed on the casting surface.
46. The casting shall be cleaned up without burr and flash, and the riser on the non machining indication shall be cleaned and flush with the casting surface.
47. The cast characters and marks on the non machined surface of the casting shall be clear and distinguishable, and the position and font shall meet the requirements of the drawing.
48. The roughness of non machined surface of casting, sand casting R, shall not be greater than 50 μ M.
49. The casting riser and flying thorn should be removed. The residual amount of pouring and riser on the non machined surface should be leveled and polished to meet the surface quality requirements.
50. The molding sand, core sand and core bone on the casting shall be removed.
51. The casting parts with inclination should be symmetrically arranged along the inclined plane.
52. The molding sand, core sand, core bone, fleshy and sticky sand on the casting shall be grinded and cleaned up.
53. The dislocation and boss casting deviation should be corrected to achieve a smooth transition and ensure the appearance quality.
54. The wrinkle on the non machined surface of the casting shall be less than 2 mm in depth and more than 100 mm in spacing.
55. The non machined surfaces of machine castings need shot peening or roller treatment to meet the requirements of cleanliness grade Sa21 / 2.
56. Castings must be water toughened.
57. The surface of the casting should be flat, and the gate, burr and sticking sand should be removed.
58. Casting defects such as cold shut, crack and hole which are harmful to use are not allowed.
59. Rust, oxide scale, grease, dust, soil, salt and dirt must be removed from the surface of all steel products to be coated before painting.