Compared with other pipes, ductile iron pipes have higher resistance to internal forces and pressure, better corrosion resistance and wear resistance. At the same time, it has the advantages of convenient construction, good interface sealing performance, and large operating safety factor. In recent years, there has been a rapid development in the market for cast iron materials. This kind of material production is more prone to cracks, heavy skin, slag inclusion quality problems. The occurrence of cracks and centrifugal casting process produce unreasonable pouring system; heavy skin is related to pouring temperature and pouring speed; slag is related to metal chemical element content and slag treatment. Prevention and control measures are: 1. Improve the centrifugal equipment, effectively prevent cracks from reducing the residence time of molten iron at high temperatures, and strengthen the gestation, especially the effect of bred inflow. The amount of inoculant added to the flow is controlled to 0.1-0.25% of the amount of molten iron; ensure uniform distribution of the mold powder and control the amount of inner surface of the tube mold to be 20-30 g/m2. Control the smelting process parameters of water-cooled metal centrifuges. Centrifuge to prevent fluid splashing caused by the phenomenon of molten iron, the sand core should be placed properly to avoid burrs. Control the composition of molten iron and reduce the silicon content of molten iron. W (Si) should be controlled at 0.8-1.2% after sizing into nodulizer. In the centrifuge casing, circular arc-shaped spray cooling pipes are evenly arranged, and they are installed in sections, and the cooling water in each section is prevented from affecting each other. 2, optimize the process parameters, reduce the weight of the pipe body to control the pouring temperature and inlet and outlet temperature of the body cooling water, shorten the interval between the two castings. The control body cooling water inlet temperature is 28-36°C and the outlet temperature is 50-57°C. In the water-cooled metal centrifugal casting process, excessive casting speed should be prevented, and the appropriate turn-up speed and main machine run speed should be adjusted; ensure that the depth of punching point of the pipe die is 0.25-0.3mm, the diameter is 4-5mm, and the points and points The edge spacing is 0.5-0.7mm. 3, control of raw materials to join, reduce slag slag defects in order to solve the problem of reducing sulfur content in molten iron, reduce the production of sulfide, should control W (S) <0.02%; properly increase the casting temperature, is conducive to slag floating; ball The content of rare earth in the agent is not too high, and the content of rare earth is preferably controlled at 1-2%; the effect of slag and slag retention of molten iron is enhanced; the flow of residual magnesium in the iron liquid is not easy to be too high (control at 0.035-0.045%). Reduce iron oxide surface oxidation. By adopting the above corresponding measures, the quality of the ductile iron pipe has been significantly improved, cracks, heavy skins, and slag inclusion defects have been greatly reduced, waste products have been reduced, and the comprehensive finished product rate has been greatly increased. Above sources of information