Part surface treatment:
1. There should be no scratches, scratches, etc. on the surface of the part.
2. The surface of the machined thread is not allowed to have black skin, bumps, buckles and burrs.
All steel parts that need to be painted must be removed from rust, scale, grease, dust, earth, salt and dirt before painting.
3. Before removing the rust, first remove the grease and dirt on the surface of the steel parts with an organic solvent, an alkali solution, an emulsifier, steam, or the like.
4. The time interval between the surface to be coated and the primer to be blasted or manually descaled shall not exceed 6h.
5. The surfaces of the rivet joints that are in contact with each other must be coated with a 30 to 40 μm antirust paint before joining. The lap joint is applied with paint, putty or adhesive. Repaint due to processing or welding damaged primer.
Heat treatment of parts:
1. After quenching and tempering treatment, HRC50～55.
2. Medium carbon steel: 45 or 40Cr parts are subjected to high frequency quenching, tempered at 350 to 370 °C, and HRC is 40 to 45.
3. Carburizing depth is 0.3mm.
4. Perform high temperature aging treatment.
Technical requirements after finishing
1. The finished parts should not be placed directly on the ground when they are placed. The necessary support and protection measures should be taken.
2. The processing surface is not allowed to have rust and affect performance, life or appearance of bumps, scratches and other defects.
3. Roll the finished surface without peeling after rolling.
4. The parts after heat treatment in the final process shall have no scale on the surface. Finished mating surface. Tooth surface should not be annealed
