Common materials for pumps

1、 Cast iron
Gray cast iron is the most commonly used type of cast iron, and the national standard code is ht. Generally, this material is used for the pump body, impeller, pump cover, and suspension of clean water pumps (diesel engine water pumps), and three brands are commonly used: ht150, ht200, and ht250. The ht150 is used for non main components such as bases and gaskets, the ht200 is used for pump bodies, pump covers, suspensions, etc., and the ht250 is used for impellers, mouth rings, shaft sleeves, etc. Different countries have different manifestations of gray iron. For example, the Japanese code is fc, the German code is gg, and the United States is first-class.
Ductile iron is a kind of cast iron with better comprehensive properties. The national standard code is QT. Because its mechanical properties are close to those of steel, and its casting and processing properties are superior to those of steel, it is often used as a substitute for cast steel. The most commonly used brands are QT450-10, QT500-7, and QT600-3. Due to limitations such as casting, the impeller of the water pump is currently used with materials, and the cut open impeller has excellent cost performance. The DIN standard for ductile iron is GGG, and the United States is for ductile iron.
In addition, there are corrosion resistant cast iron - high silicon cast iron, wear-resistant cast iron - white cast iron, high toughness cast iron - malleable cast iron, and so on. Due to some difficulties in processing, there are not many products used.
2、 Cast steel
Due to the high strength of cast steel, usually when the pressure& GT; At 1.6 mpa, the pressurized components are mostly cast steel, with the national standard code being zg, and the most commonly used brand being zg230-450. Japanese and Americans usually use cs to denote cast steel.
3、 Stainless steel
The most widely used stainless steel is austenitic stainless steel, such as 0Cr18Ni9, 1Cr18Ni9Ti, 0Cr18Ni12Mo2Ti, and so on. Austenitic stainless steel is an excellent corrosion resistant material except for small amounts of media such as hydrochloric acid and dilute sulfuric acid. It is the most commonly used corrosion resistant material for chemical pumps. In Japan and the United States, SS304, SS316, and SS316L are commonly used to represent austenitic stainless steel. Martensitic stainless steels such as 2Cr13 and 3Cr13 have better mechanical properties than austenitic stainless steels, and are commonly used as materials for pump shafts and bushings. The corresponding code for Japan and the United States is SS420. In addition, high alloy stainless steel (alloy 20) and dual stainless steel are also ideal corrosion resistant materials.
4、 Carbon structural steel
Generally, it is divided into ordinary carbon structural steel and high-quality carbon structural steel. The most representative ordinary carbon structural steel is Q235, which is widely used in various steel plates and sections. The most representative high-quality carbon steel is 45 steel, widely used in non corrosive pump shaft materials.
5、 Alloy steel
The most representative alloy steel is 40cr, commonly used as a high-strength pump shaft material.
6、 Non metallic materials
The non-metallic materials used for pumps are mainly used for sealing, such as PTFE, fluororubber, nitrile rubber, etc. Among them, PTFE is used for chemical pump seals and mechanical seals due to its excellent corrosion resistance and high temperature resistance. It is suitable for almost all chemical media at 250 ° C. Its disadvantages are high hardness and difficult assembly. Large.
Fluororubber is also a good temperature and corrosion resistant material. The upper limit of temperature resistance is 160 ℃. When the user has no special requirements, it is recommended to use the sealing ring made of this material for chemical pumps; Nitrile rubber is mainly used for static sealing of oil or water resistant media.