Technical requirements for castings
No cold partition, cracks, shrinkage, penetrating defects, and serious incomplete defects (such as under-casting, mechanical damage, etc.) are allowed on the surface of the casting.
1. The casting tolerance zone is symmetrical to the basic size configuration of the rough casting.
2. No cold partition, cracks, shrinkage, penetrating defects, and serious incomplete defects (such as under-casting, mechanical damage, etc.) are allowed on the surface of the casting.
3. The castings should be cleaned up without burrs or flashes. The pouring riser on the non-processing indication should be cleaned and flush with the surface of the casting.
4. The casting characters and marks on the non-machined surface of the casting should be clear and identifiable, and the position and font should meet the drawing requirements.
5. The roughness of the non-machined surface of the casting, sand casting R, is not more than 50μm.
6. Castings should be clear of pouring risers, spurs, etc. The residual amount of the pouring riser on the non-processed surface should be leveled and polished to meet the surface quality requirements.
7. The molding sand, core sand and core bone on the casting should be cleaned.
Technical requirements for forgings
1. The nozzles and risers of each steel ingot should be removed enough to ensure that the forgings are free of shrinkage and serious deflection.
2. Forgings should be forged on a forging press with sufficient capacity to ensure that the forgings are fully forged.
3. Forgings are not allowed to have visible cracks, folds and other appearance defects that affect use. Local defects can be removed, but the cleaning depth should not exceed 75% of the machining allowance. The defects on the non-machined surface of the forging should be cleaned and smoothly transitioned.
4. White spots, internal cracks and residual shrinkage holes are not allowed in forgings.
8. The castings have inclined parts, and the dimensional tolerance zone should be arranged symmetrically along the inclined plane.
9. The molding sand, core sand, core bone, succulent, sticky sand, etc. on the castings should be smoothed and cleaned.
10. The right or wrong type, casting deviation of the boss, etc. should be corrected to achieve a smooth transition and ensure the appearance quality.
11. The wrinkles on the non-machined surface of the casting should have a depth of less than 2mm and a spacing greater than 100mm.
12. The non-machined surface of the machine product castings needs to be shot blasted or roller treated to meet the requirements of Sa2 1/2 cleanliness.
13. Castings must be treated with water toughness.
14. The surface of the casting should be smooth, and the gate, burr, sticky sand, etc. should be removed.
15. Castings are not allowed to have casting defects such as cold partitions, cracks, holes and so on that are detrimental to use.