Technical Requirements For Ductile Iron Pipe Fittings

1. The chemical composition of ductile pipe fittings should not exceed 0.30% phosphorus and 0.10% sulfur.

2. The surface hardness of continuous cast iron pipes should not be greater than HB210, and the surface hardness of metal and sand centrifugal cast iron pipes should not be greater than HB230.

3. The air tightness test medium adopts compressed air. The air tightness test pressure should not be lower than 0.3MPa (3kgf/mm2f).

4. The structure cast iron pipe should be gray cast iron, with dense structure, easy to cut and drill.

5. Surface quality The inner and outer surfaces of the cast iron pipe are not allowed to have obvious defects such as cold partitions, cracks, dislocations, etc. that hinder the use.

6. Various local defects of thinning shall not exceed (2+0.05T)mm. With the consent of the purchaser, local defects can be repaired. However, the repaired cast iron pipes shall be re-tested for hydraulic pressure and air tightness according to this standard.

7. In addition to meeting the above requirements, the sealing surfaces of sockets and sockets must not have continuous axial grooves and pockmarked surfaces.

8. The outline of the socket flange should be clear, and slight defects that do not affect the use are allowed.

9. The inner and outer surfaces of the coated pipe should be coated with bitumen or other materials. If required to be lined with cement mortar or uncoated

10. The coating of cast iron pipes for water supply should be insoluble in water, and the water should not produce odor and taste, and the content of impurities.