In order to improve the tensile strength of its products, angle valve casting should adopt a lower carbon equivalent to a certain extent. The carbon content in valve castings is mostly 2.6% to 3.6%. The lower limit should be taken according to the wall thickness of the casting. The content of manganese, generally the manganese content of the valve casting is 0.4% to 1.2%, and the upper limit is taken as much as possible in the case where the casting does not have a white mouth.
Angle valve casting can also adopt alloying method to improve the tensile strength of castings. Appropriate addition of trace alloys such as chromium, molybdenum, tin and other elements can also significantly improve the tensile strength of gray cast iron. At the same time, we must cooperate with the treatment of molten iron.
The determination of the stress relief annealing temperature for angle valve casting must take into account the chemical composition of the cast iron. Ordinary valve castings When the temperature is above 550 ° C, partial cementite graphitization and granulation may occur, resulting in lower strength and hardness. When an alloying element is contained, the temperature at which cementite begins to decompose can be increased to about 650 °C.
Related Industry Knowledge
- Reasons for affecting efficiency
- Pump selection
- Classification of impeller
- Impeller shape classification
- How to prevent impeller wear
- Impeller anti-corrosion measures
- Pumps-working principle
- Open impeller
- Multistage pumps how to type?
- Sewage pump, sewage treatment suppo...
- Process design and modeling materia...
- Copper alloy pump body castings and...
- Raw materials and properties of tin...
- Casting temperature and process req...