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1. Remove the oxide scale from the parts. 2. The surface of the machined part shall be free from defects such as scratches and abrasions that damage its surface. 3. Remove burrs and flash. 4. After quenching and tempering, HRC 50–55. 5. The parts are subjected to high-frequency quenching and tempered at 350–370°C, achieving a hardness of HRC 40–45. 6. Carburization depth: 0.3 mm. 7. Perform high-temperature aging treatment. 8. The unspecified form tolerances shall meet the requirements of GB1184-80. 9. The allowable deviation for unmarked length dimensions is ±0.5mm. 10. The casting tolerance zones are symmetric with respect to the basic dimensions of the blank casting. 11. Radius of fillet R5 not specified. 12. Unless otherwise specified, all chamfers are 2×45°. 13. An acute angle becomes obtuse. 14. All seals must be soaked in oil before assembly. 15. When assembling rolling bearings, heat installation using machine oil is permitted, provided that the temperature of the oil does not exceed 100°C. 20. After the gears are assembled, the contact patches on the tooth surfaces and the side clearance shall comply with the requirements of GB10095 and GB11365. 21. Sealing fillers or sealants may be used when assembling the hydraulic system, but care must be taken to prevent them from entering the system. 22. Parts and components to be assembled (including purchased parts and outsourced components) must have a certificate of approval from the inspection department before they can be assembled. 23. Parts must be cleaned and purified before assembly; they must be free of burrs, flash, scale, rust, chips, oil stains, coloring agents, and dust. 24. Before assembly, the main fit dimensions of the parts and components, particularly the interference fit dimensions and related precision, should be rechecked. 25. During assembly, the parts must not be dented, scratched, or corroded. 26. When tightening screws, bolts, and nuts, it is strictly prohibited to strike them or use inappropriate screwdrivers and wrenches. After tightening, the screw groove, nut and screw, as well as the bolt head must not be damaged. 27. For fasteners with specified tightening torque requirements, torque wrenches must be used to apply the torque as specified. 28. When securing the same component with multiple screws (bolts), these screws (bolts) must be tightened in a cross, symmetrical, sequential, and even manner. 29. When assembling taper pins, a coloring inspection should be carried out on the pin and the hole; the contact rate should be no less than 60% of the fit length, and it should be evenly distributed. 30. The flat key should make even contact with both sides of the keyway on the shaft, and there should be no gaps in the mating surfaces. 31. During spline assembly, the number of tooth surfaces in contact shall be no less than 2/3, and the contact ratio in the length and height directions of the spline teeth shall be not less than 50%. 32. After the flat key (or spline) with a sliding fit is assembled, the mating parts should be able to move freely without any uneven tightness. 33. After bonding, the excess adhesive that has flowed out should be removed. 34. There must be no jamming between the outer ring of the bearing and the semi-circular holes in the open bearing housing and bearing cover. 35. The outer ring of the bearing should make good contact with the open bearing housing and the semi-circular holes in the bearing cover; when using color inspection, it should be in uniform contact within an angle of 120° relative to the center line with respect to the bearing housing, and 90° relative to the center line with respect to the bearing cover. When checking with a feeler gauge within the aforementioned range, a 0.03 mm feeler gauge must not fit into 1/3 of the outer ring’s width. 36. After installation, the outer ring of the bearing should make even contact with the end face of the positioning end bearing cover. 37. After the rolling bearing is installed, it should rotate smoothly and effortlessly by hand. 38. The mating surfaces of the upper and lower bearing shells must fit tightly together; a 0.05 mm feeler gauge should not be able to fit between them. 39. When fixing the bearing shells with set screws, drilling, reaming, and fitting the screws should be carried out while ensuring that the mating surfaces of the shell flanges and end faces are level with the corresponding mating surfaces and end faces of the bearing holes. The pin must not loosen after it has been inserted. 40. The bearing body of the spherical bearing and the bearing seat should be in uniform contact; this can be checked using the coloring method, and the contact area should be no less than 70%. 41. Alloy bearing linings shall not be used if their surface turns yellow; no nucleation shall occur within the specified contact angle, and the area affected by nucleation outside this angle shall not exceed 10% of the total area of the non-contact region. 42. The reference end face of the gear (worm gear) should fit tightly against the shaft shoulder (or the end face of the positioning sleeve); a 0.05 mm feeler gauge should not be able to fit between them. It is also necessary to ensure that the reference end face of the gear meets the requirements for perpendicularity to the axis. 43. The mating surface between the gearbox and the cover should be in good contact. 44. Thoroughly inspect and remove any sharp edges, burrs, and foreign objects remaining from the part processing before assembly. Ensure that the seal is not scratched when installed. 45. The surface of the casting must be free from cold shuts, cracks, shrinkage cavities, and penetrating defects, as well as severe defects related to incomplete filling or mechanical damage. 46. The castings shall be thoroughly cleaned; there shall be no burrs or flash, and the gates and risers that are not part of the intended surface finish shall be removed so that they are level with the casting surface. 47. The casting marks and labels on the unworked surfaces of castings shall be clearly visible, and their position and font shall meet the requirements specified in the drawings. 48. The roughness of the unworked surface of the casting, for sand casting R, shall not be greater than 50 μm. 49. Castings should be free of gates, risers, and other protrusions. The residues of gates and risers on the unprocessed surfaces must be leveled and polished to meet the surface quality requirements. 50. The molding sand, core sand, and core shims on the casting must be removed completely. 51. In castings with inclined sections, their dimensional tolerance zones should be arranged symmetrically along the inclined surface. 52. The molding sand, core sand, core shims, excess material, and sticky sand on the castings should be scraped and smoothed out, and cleaned thoroughly. 53. Errors such as wrong shapes and uneven protrusions in casting should be corrected to achieve a smooth transition, thereby ensuring the quality of the appearance. 54. On the unworked surfaces of castings, wrinkles with a depth of less than 2 mm should have a spacing of more than 100 mm. 55. The unmachined surfaces of machine product castings must be subjected to shot blasting or roller treatment to achieve a cleanliness level of Sa2 1/2. 56. Castings must undergo water tempering treatment. 57. The surface of the casting should be smooth, and gates, burrs, sand adhesion, etc. should be removed completely. 58. Castings are not allowed to have casting defects such as cold shuts, cracks, holes, etc., which could impair their usability. 59. On the surfaces of all steel components that require painting, rust, scale, grease, dust, dirt, salt, and other contaminants must be removed before applying paint. 60. Before rust removal, use organic solvents, alkalis, emulsifiers, steam, etc. to remove grease and dirt from the surface of steel parts first. 61. The time interval between the surface to be painted, which has been shot-blasted or manually derusted, and the application of the primer shall not exceed 6 hours. 62. The surfaces of the riveted parts that come into contact with each other must be coated with an anti-rust paint of a thickness of 30–40 μm before assembly. The overlapping edges should be sealed with paint, putty, or adhesive. The primer that has been damaged due to processing or welding must be repainted. 63. Before assembly, all pipes should have their end burrs and sharp edges removed, and chamfers applied. Use compressed air or other methods to remove debris and loose rust adhering to the inner wall of the pipe. 64. Before assembly, all steel pipes (including prefabricated pipelines) must undergo degreasing, pickling, neutralization, washing, and rust prevention treatment. 65. During assembly, tighten the parts that are fixed by threaded connections, such as pipe clamps, supports, flanges, and joints, to prevent loosening. 66. All welded joints of the prefabricated pipes must undergo pressure testing. 67. When replacing or transferring piping, the pipe connection points must be sealed with tape or plastic tubing to prevent any debris from entering, and labels must be attached. 68. Before performing patch welding, the defects must be completely removed, and the groove surface should be made smooth and even, with no sharp corners present. 69. Depending on the defects in the cast steel parts, defects in the patch welding area can be removed by methods such as chiseling, grinding, carbon arc gas gouging, oxygen cutting, or mechanical machining. 70. All contaminants such as sand, oil, water, and rust within 20 mm of the weld repair area and the groove perimeter must be thoroughly removed. 71. Throughout the entire process of patch welding, the temperature in the preheating zone of the cast steel part must not be lower than 350°C. 72. Whenever conditions permit, weld in a horizontal position as much as possible. 73. When performing patch welding, the welding rod should not be swung too much laterally. 74. When surfacing welding cast steel parts, the overlap between weld passes shall not be less than 1/3 of the width of the weld pass. 75. The gates and risers of each steel ingot should have sufficient amount of cut-off to ensure that the forgings are free from shrinkages and severe warping. 76. forgings should be forged on a sufficiently capable forging press to ensure thorough forging throughout their interior. 77. Forgings shall not have any visibly visible cracks, folds, or other visual defects that affect their usability. Local defects can be removed, but the cleaning depth must not exceed 75% of the machining allowance; defects on the unmachined surfaces of forgings should be cleaned thoroughly and smoothed over. 78. Forgings are not allowed to have white spots, internal cracks, or residual shrinkage cavities. 81. Finished parts must not be placed directly on the ground; appropriate support and protective measures should be taken. The machined surface must be free from rust, corrosion, as well as any dents, scratches, or other defects that could affect its performance, lifespan, or appearance. 82. The surface after rolling finish machining must not show any peeling. 83. The surfaces of the parts after heat treatment in the final processing stage should be free of oxide scale. The finely machined mating surfaces and tooth surfaces must not be annealed. 84. The machined thread surfaces shall be free from defects such as black skin, dents, misalignment of threads, and burrs. 85. Blueing and discoloration phenomena.