Processing
The Production Flow Chart of Ductile Iron Pipes
1.Molten |
The raw materials are molten in electric induction furnace. The temperature and composition of the molten iron are monitored and controlled in the holding furnace. |
2.Desulfurizing, Spheroidizing and Inoculation Treatments |
The molten iron is treated with magnesium and become spheroidized. |
3.Centrifugal casting |
Two methods are applied in the centrifugal casting: one is metal mold water-cooling process, the other is wit-spray hot mold process. |
4.Continuous heat treatment |
After casting, the pipe is sent to the heat treatment furnace to change its metallographic structure. |
5.Test and inspection |
After mechanical processing, metallographic examination, flattening test, hydrostatic pressure test and scale inspection are applied. |
6.Inspection and Testing |
After inspection, the internal of pipe is applied with a cement mortar lining or epoxy powder coating. |
7.Lining, Coating and Final Inspection |
The outside of pip is applied with metallic zinc, on top of metallic zine, bitumen paint is applied. |
The Production Flow Chart of Ductile Iron Fittings
1.Molten |
The raw materials are molten in electric induction furnace. The temperature and composition of the molten iron are monitored and controlled in the holding furnace. |
2.Modeling and casting |
The molten iron is treated with magnesium and become spheroidized. |
3.Modeling and casting |
According to the size of fittings: Either furan resin sand molding method or cement molding method is applied. |
4.Spray cleaning and machining |
After the casting is taken out, the casting is sprayed and grounded, and then machine processed. |
5.Test and inspection |
After mechanical processing, metallographic examination, flattening test, hydrostatic pressure test and dimensional inspection are applied. |
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6.After inspection, the internal surface of fitting is applied with epoxy powder coating. |
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7.The external surface of fitting is applied with metallic zinc and bitumen coating. |