1. Cast steel valves
Cast steel valves are used to pour castings of steel. A kind of casting alloy. Cast steel is a steel casting produced by casting method. Cast steel is mainly used in the manufacture of some complex shapes, difficult to forge or cutting process forming and require high strength and plasticity of the parts.
2. Cast iron valves
Cast iron is a carbon content of more than 2% of the iron-carbon alloy. Generally what we call cast iron valves, with ductile iron, grey cast iron iron by spheroidal treatment obtained, the precipitation of graphite is spherical, referred to as ductile iron. Than ordinary grey cast iron has higher strength, better toughness and plasticity.
Classification of cast iron valves:
Cast iron can be divided into: grey cast iron, white cast iron, malleable cast iron, ductile iron, peristaltic cast iron, alloy cast iron.
3. Distinction:
The first material is different, one is cast steel, one is cast iron.
Second, the pressure resistance of the medium is different, cast steel is a high-pressure valve, cast iron is a low-pressure valve.
Third, the sealing is not the same, cast steel valve sealing performance is better than cast iron valve.
Fourth, the use of different, cast steel valves can be used for high temperature and high pressure environment, cast iron valves can only be used at lower temperatures, low pressure environment.
Cast iron valves are used at a temperature of about 125 degrees, suitable for tap water, sewage and other low-temperature liquid use; cast steel valves can be used at a maximum temperature of 425 degrees, suitable for use in boilers, steam pipelines.
Cast iron is more rigid than cast steel, brittleness is also greater than cast steel, and cast steel has better plasticity and toughness than cast iron, so cast iron is generally used in the pipeline at lower pressure, but also can only be applied to the pipeline at room temperature above, because of the pressure or temperature increases will indicate that the valve will have a certain amount of deformation of the trace of cast iron valves is unfavourable.
Relative to cast iron valves, cast steel valves can be used in the pressure or temperature is relatively high in the pipeline.
