What Are The Technical Requirements For Machine Parts Processing?

- May 20, 2019-

What are the technical requirements for machine parts processing? Simple understanding of mechanical parts processing is actually a process of changing the shape and size or performance of parts with processing machinery. But in this process, we need to pay attention to some corresponding requirements:

First, we need to pay attention to the contour processing of parts:

1. Shape tolerance without injection should meet the requirements of GB1184-80; 2. Allowable deviation of length and dimension without injection (+0.5mm); 3. radius of fillet without injection R5; 4. chamfer without injection is C2; 5. sharp chamfer is blunt; 6. sharp chamfer is blunt to remove burr flying edge.

Secondly, in the surface treatment of parts, we need to do:

1. There should be no scratches, scratches and other defects on the surface of parts. 2. No black skin, bumps, chaos and burrs are allowed on the surface of threads. Before painting, rust, oxide scale, grease, dust, mud, salt and dirt must be removed on the surface of all steel parts that need to be coated. 3. Before rust removal, organic solvents, alkali, etc. should be used first. The grease and dirt on the surface of steel parts can be removed by liquid, emulsifier and steam. 4. The surface of riveted parts contacting each other must be coated with anti-rust paint of 30-40 micron thickness before joining. The lap edge shall be sealed with paint, putty or adhesive. Due to processing or welding damage of the primer, it should be re-painted; 5. The time interval between the surface to be painted and the primer to be painted after shot peening or manual rust removal shall not be more than 6 hours.

Thirdly, the technical requirements of mechanical parts after precision processing:

1. Parts after finishing shall not be placed directly on the ground, and necessary supporting and protective measures shall be taken; 2. No rust borers and defects affecting performance, life or appearance shall be allowed on the surface; 3. No peeling shall occur on the surface after rolling; 4. Parts after heat treatment in the final process shall have no oxide skin on the surface. There should be no annealing for the finish machined mating surfaces and tooth surfaces.

Fourthly, heat treatment of parts: 

1. After quenching and tempering, HRC50-55; 2. Medium carbon steel: 45 or 40Cr parts are quenched at high frequency, tempered at 350-370 C, HRC40-45; 3. Carburizing depth 0.3mm; 4. High temperature aging treatment.

Fifth, sealing treatment of mechanical parts:

1. Seals must be soaked with oil before assembling. 2. Strict inspection and removal of sharp angle, burr and foreign matter remained in parts processing before assembling. Ensure that the seals are not scratched when they are loaded; 3. Remove the excess adhesives flowing out after bonding.

Understanding the above five technical processing requirements and paying attention to these problems in the manufacturing process of mechanical parts, we can produce high-quality mechanical parts and equipment to meet the market demand.