Is the valve body of the valve made of forged steel or cast steel?
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I am working on the technical specifications for valves, and the templates I found specify that the valve body can be made of cast steel or forged steel. Should I use forged steel or cast steel? Used in shale gas gathering and transportation projects, ball valves, gate valves, globe valves, and safety valves are all available. Natural gas contains 1.7% carbon dioxide, no hydrogen sulfide, and is saturated with water; the chloride ion concentration in this water is about 20,000 mg/L. The design pressure is 7.5 MPa, and the temperature ranges from around 20 to 50 degrees Celsius.
Forged steel is definitely used when costs permit. Wrought steel is much more expensive. But the quality has to be good.
For small-diameter, low-pressure applications, cast steel can be used; for larger diameters with higher pressure ratings, forged steel must be employed.
1. Ordinary valves: those with a diameter of DN40 and below are made of forged steel, while those with a diameter of DN50 and above are made of cast steel. 2. High-pressure and hydrogenation valves: forged steel for those below DN150; cast steel can be used for those above DN150 due to the difficulty in forging and the limited availability of molds.
Forged steel is used for DN50 and below, while cast steel is used for DN50 and above. Large diameters are all made of cast steel. The strength is sufficient.
Thank you all for your advice. It was quite challenging for me to prepare a technical specification sheet for valves for the first time; in the past I had only worked on small projects involving inspections and modifications, and the clients themselves purchased the materials, so I didn’t pay much attention to it. Some projects used A105 and 16Mn, while others used WCB.
I’m a new recruit with little experience; I’ve learned how to work with various materials for flanges, elbows, tees, reducers, and blind flanges. If you need any assistance, you can contact me via phone or WeChat at 13668620835
Ball valves can be made of forged steel, while the material for other valves depends on their shape; for other types of valves, if their shape is complex, using forged steel would result in much higher costs, sometimes even double the cost. For ball valves, forged steel can be used, with little increase in cost. There are many references available for the technical specifications and data sheets of ball valves; the design institutes of Sinopec and CNPC have standardized the specifications for oil and gas transmission.
There are corresponding standards for selecting the casting and forging materials of valves. Design agencies have references to follow when carrying out initial designs, and these selections must also be made in accordance with the owner’s requirements and the conditions under which the valves will operate.