Valve material

The valve body material for valves can be either forged or cast; the choice depends mainly on the valve’s size, pressure rating, and operating environment. Generally, forged components are preferred for small-sized valves, as forging provides better mechanical properties and density, making them suitable for high-pressure environments. Large-sized valves are often made from castings, mainly because the casting cost is lower, making it more suitable for manufacturing valve bodies of large size or complex shapes. Therefore, the material selection for the valve body is indeed related to its size. .

For conventional non-petroleum enterprises, casting is generally used; for globe valves and gate valves in the forged steel series below DN50, forged steel is the most common material. Other valves include globe valves, ball valves, and gate valves, most of which are cast.

The material of the valve body should be determined based on various factors such as the pressure, temperature, and corrosiveness of the medium; there can be no one-size-fits-all approach.

For small sizes of 40 and below, forgings of A105 are commonly used, while for larger sizes of 50 and above, castings of A216 WCB are typically used. You can look up an existing pipeline grade table.

Generally, castings are used more frequently. However, in situations where certain operating conditions prohibit the use of castings or where it is more appropriate to use other types of blanks, structures such as forgings, forge-welded parts, or plate-welded parts should be chosen according to the specific circumstances; in such cases, deformed alloys suitable for casting must be used. The performance requirements for their wrought alloys and castings are generally the same, but their chemical compositions differ slightly. This is because, while maintaining the required performance levels, castings need to have good castability, whereas other wrought alloy materials require good ductility for processing purposes. The deformed alloys used for the main body materials of valves mainly include forgings, sheets, and pipes. Thus, depending on the manufacturing process of the material, its main types can be divided into four categories: castings, forgings, sheets, and pipes.

The difference between forged steel and cast steel mainly lies in the different processing methods (forging and casting) used for the steel. Forging is a plastic deformation process, while casting is liquid-state molding. Here, for valves with a capacity of 2500CL and a temperature of 300°C, there are both cast and forged versions available; generally, the forged ones are of better quality.

It depends on the place of use, the requirements

The choice between forgings and castings as valve body materials is quite flexible. Many factors and conditions are involved, such as pressure, temperature, medium corrosivity, installation conditions, and so on. A specific choice is needed depending on the circumstances. Rather than making generalizations. Forgings have better performance than castings, but castings are more corrosion-resistant. So it depends on the circumstances.

It is related to the pressure rating and operating temperature; there are both forged and cast versions.