Requirements for non - standard castings, coating and piping

Non - standard parts processing casting requirements

1. Cold insulation, cracks, shrinkage cavity and penetrating defects and serious incomplete defects (such as undercasting, mechanical damage, etc.) are not allowed on the surface of casting.

2. The casting shall be cleaned without burr or flash, and the casting riser on the non-processing indication shall be cleaned flush with the casting surface.

3. The cast letters and marks on the non-machined surface of the casting shall be clear and legible, and the position and font shall meet the requirements of the drawing.

4. Roughness of unprocessed surface of casting, R of sand casting, no more than 50 micron.

5. Casting risers and flying spines should be removed.The residual amount of pouring nozzle on the non-processed surface should be leveled and polished to meet the surface quality requirements.

6. The molding sand, core sand and core bone on the casting should be cleaned.

7. Where the casting is inclined, the dimensional tolerance zone shall be configured symmetrically along the inclined plane.

8. Sand, core sand, core bone, fleshy, sticky sand, etc. on the casting should be shoveled and ground flat and cleaned.

9. The casting deviation of wrong type and convex boss shall be corrected to achieve smooth transition and ensure the appearance quality.

10. Folds on the non-machined surface of the casting with a depth less than 2mm and a spacing greater than 100mm.

11. The non-processed surface of machine castings shall be shot peening or roller treatment to meet the requirements of cleanliness Sa2 1/2 level.

12. Castings must be toughened with water.

13. The casting surface shall be flat, and the gate, burr and sand shall be cleaned.

14. Casting defects such as cold insulation, cracks, holes, etc. are not allowed in the casting.'

Non-standard parts processing '

Non-standard parts processing coating requirements

1. Rust, scale, grease, dust, dirt, salt and dirt, etc. must be removed from the surface of all steel parts to be coated before painting.

2. Before derusting, remove grease and dirt on the surface of steel products with organic solvent, alkali, emulsifier, steam, etc.

3. The time interval between the surface to be coated after shot peening or manual derusting and priming shall not be more than 6h.

4. The surface of the riveting parts in contact with each other must be coated with a thickness of 30 to 40 micron anti-rust paint before connection.Lap edges shall be sealed with paint, putty or adhesive.Reapply primer damaged by machining or welding.

Non-standard parts processing piping requirements

1. Before assembling, all pipes shall be free of flash, burr and chamfering at the pipe end.Use compressed air or other means to remove debris and rust from the inner wall of the pipe.

2. Before assembly, all steel pipes (including prefabricated pipes) shall be degreased, pickled, neutralized, washed and rust-proof.

3. When assembling, tighten the threaded connection parts of pipe clips, supports, flanges and joints to prevent loosening.

4. All welded parts of prefabricated pipes shall be subjected to pressure test.

5. When piping is replaced or transferred, the separation port of the pipeline must be sealed with adhesive cloth or plastic pipe to prevent any sundries from entering and labeled.