Key differences between the application of valves made of steel and cast iron

Industrial valves are classified into two types — iron and steel. The material used depend on the technical parameters of the design. For design parameters, gate valves, steel and cast iron do not differ from each other. The movement of the shutter is perpendicular to the flow. There are also variations that include a retractable and static stock. The diameters of the passages in models of steel and cast iron are the same. Management there are two types – manual or remote. The main differences between cast iron and steel valves:
  • The material of manufacture.
  • The permissible level of pressure.
  • The sphere of use.
  • Cost.

The level of pressure valves, of steel and cast iron
A significant difference between valves of steel and cast iron is the presence of a certain optimal operating pressure. Cast iron is characterized by greater fragility, but corrosive resistance. Gate valve made of grey cast iron, have a maximum pressure of 1.0 MPa (10 kg / cm2), which is used for diameters from 30 to 60 cm gate Valves, made of ductile cast iron type, may be used in higher level pressure up to 1.6 MPa.
Steel is a durable, plastic that can sustain high temperature. The weak point of this material – susceptibility to corrosion. Gate valves of steel have the ability to function at a pressure equal to from 1, 6 to 6, 4 MPa. Moreover, all variations of steel, including steel gate valve DN80, provide a flanged connection and machined endings to weld. This makes it possible to guarantee a sufficient degree of safety during their use at elevated pressures in the pipeline.


Therefore, choosing a valve for a pipeline, it is necessary to focus our attention on the difference of the maximum allowable pressure. You should also pay for the technical data of the model. So, according to the standard requirements, do not install gate valves of cast iron for highways designed for thermal networks.

Price and application area of the valves
Products made from stainless steel are more expensive compared to cast iron models. Models made of cast iron capable of providing reliable operation with light loads. If the working environment meets the established parameters, applies the modification of cast iron.
Cast iron models have less versatility compared to steel products. Valves made of steel are used for different pipelines for gas, oil, water with a diameter of 60 centimeters. For more aggressive environment used a model of stainless steel.