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1. The standard tolerance of outline not noted in the drawing should be in accordance with the requirements of GB1184-80 guidelines.
2. The standard tolerance size of length not noted should be within ± 0.5 mm.
3. The radius of Corners not noted can be as R5 unless otherwise specified, blend all intersections.
4. Chamfer: Corners can be chamfered as C2 unless otherwise specified.
5. Remove burrs and flashes.
1. On the machined surface of the parts, there should be no scratches, abrasions and other defects that damage the surface of the parts.
2. The machined thread surface should not be allowed to have defects such as black skin, bump, messy buckle, and burr.
Before painting, all steel parts must be free of rust, oxide, grease, dust, mud, salt, and dirt.
3. Before removing rust, remove grease and dirt from the surface of steel parts with organic solvent, alkali, emulsifier, steam, etc.
4. The time interval between the surface to be coated by shot blasting or manual rust removal and the primer coating shall not be more than 6hrs.
5. The contacted face between riveted parts must be coated with a thickness of 30 ~ 40μm anti-rust paint before coating. The edge of the lap joint should be closed with paint, putty, or adhesive. The primer damaged due to processing or welding should be repainted.
1. Tempering treatment, HRC50 ~ 55.
2. Medium carbon steel 45 or 40Cr, high-frequency quenching 350 ~ 370 ℃, and then tempering, HRC40 ~ 45.
3. Carburizing depth: 0.3mm.
4. High-temperature aging treatment in final processing.
1. After fine machining, parts shall not be placed directly on the ground, the necessary supports and protection measures must be adopted.
2. Processing face does not allow rust and defects that affect the performance, life or appearance like the bump, scratches.
3. No peeling allowed on the surface of rolling finishing.
4. After final heat treatment process, no oxide scales on the surface, the tooth surface and contacted face should not be annealed.
1. Each sealing parts must be soaked in oil before assembly.
2. Before assembly, the inspection must be done strictly to ensure the removal of all of residual, sharp corners, burrs, and foreign objects. Ensure that the seals are not scratched when they are installed.
3. After bonding, the excess adhesive should be removed.
1. After gear assembly, the contact spots and side gaps between the tooth faces should conform to GB10095 and GB11365 guidelines.
2. Gear (worm wheel) benchmark end face and shaft shoulder (or positioning sleeve end face) should be fitted. The 0.05mm gaps should not allow the gauge plug in. And it should ensure the perpendicularity requirements for the gear benchmark end face and axis.
3. The combination face of gear box and cover should be in good contact.
1. Casting tolerance should comply in the basic size configuration of the blank casting.
2. The casting surface does not allow cold shut, cracks, shrinkage and penetrating defects and serious defective class defects (such as under-casting, mechanical damage, etc.)
3. Castings should be cleaned up, no burrs, flashes, the sprue should be cleaned up and flushed with the surface of the casting unless it is indicated in machining.
4. Castings and signs on the non-machined surface should be clear and legible, the location and font should be in line with the requirements of the drawings.
5. The roughness of the non-machined surface of the casting, sand casting R, should be no more than 50μm.
6. Castings should be cleared of sprues, flying spurs, etc. The residue of the sprue on the non-machined face should be leveled and polished to achieve the surface quality requirements.
7. Molding sand, core sand and core rod should be cleared.
8. To the casting with an inclined part, its size tolerance zone should be symmetrically configured along the inclined side.
9. The molding sand, core sand, core rod, sticky sand and residual on the casting shall be shovel ground smooth and cleaned.
10. The wrong type, convex casting deviation, etc., should be corrected to achieve a smooth transition and ensure the appearance quality.
11. The wrinkles on the non-machined face of the castings, the depth should be less than 2mm and the spacing should be more than 100mm.
12. The non-machined surface of the castings of machine products are required to be shot blasted or roller-treated to reach the requirement of cleanliness Sa2 1/2 level.
13. Castings must be treated with water toughening.
14. The surface of the casting should be flat, and the sprue, burr and sticky sand should be cleared.
15. Castings are not allowed to have cold shut, cracks, holes, and other casting defects that are detrimental to use.
1. The spout and riser of each ingot should have enough removal amount to ensure that the forging is free from shrinkage and serious deflection.
2. The forgings should be forged and formed on the forging press with sufficient capacity to ensure that the forgings are fully forged inside.
3. Forgings are not allowed to have visible cracks, folding and other defects that affect the appearance of use. Partial defects can be removed, but the cleaning depth shall not exceed 75% of the machining allowance, the defects on the non-machined surface of the forgings shall be cleaned up and rounded transition.
4. Do not allow the existence of white spots, internal cracks, and residual shrinkage of the forgings.
