General operating temperature of ball valves
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Help: General operating temperature of ball valves
What is the general operating temperature for ball valves? Ball valves made of different materials and with different designs can handle different temperatures. Is 500°C considered a high temperature? Ball valves are used in many applications
The body material of the selected ball valve is alloy steel A182-F11, with a pressure rating of PN10.0. The seat sealing surface is made of PTFE, the ball sealing surface is made of 304, and the valve stem is also made of 304
The body of the ball valve is made of alloy steel A182-F11, with a pressure rating of PN10.0. As it is a CrMo alloy steel, the valve can withstand relatively high temperatures; however, since the valve seat sealing surface is made of PTFE, the temperature cannot be too high. We have used similar materials before, requiring a temperature below 260 degrees℃
The body of the ball valve is made of alloy steel A182-F11, with a pressure rating of PN10.0. As it is a CrMo alloy steel, the valve can withstand relatively high temperatures; however, since the valve seat sealing surface is made of PTFE, the temperature cannot be too high. We have used similar materials before, requiring a temperature below 260 degrees℃
The PTFE sealing surface can handle temperatures up to 260 degrees! It is recommended to use it at around 180 degrees. Generally, when the operating temperature of a ball valve exceeds 200 degrees, a hard seal should be used
Not more than 200 degrees. :lol
This issue concerns the selection of a pressure tapping valve for the orifice plate on a 3.5 MPa steam pipeline; originally, a ball valve was chosen for this purpose. If a ball valve cannot be used in such high-temperature environments, what type of valve should be used instead?
It is not recommended to use ball valves for 3.5MPa steam pipelines; otherwise, a metal hard-seal design must be employed, which is very costly. Ball valves with domestic PTFE seat generally start to have problems when the operating temperature exceeds 150°C. The use of gate valves or globe valves with flexible graphite packing can meet the requirements.
To answer your question, you first need to provide the following information: Is 1.3.5 MPa steam saturated steam or superheated steam? If it is superheated steam, then what is the temperature of that steam? 2. Is it a requirement in your design specifications that ball valves must be used? This is because slow-opening and slow-closing valves are preferred for steam pipes, while fast-opening and fast-closing valves are generally used only during cleaning and purging after the pipes have been installed.
The original poster didn’t clarify one thing, namely the size of the valve and the specific temperature. I think the conditions you mentioned are not suitable for choosing a ball valve! Ball valves are rarely used in steam pipelines. I agree more with what was said by users on floors 10 and 11! Generally, globe valves are used in steam pipelines with a diameter of DN200 or less, while gate valves are typically used for pipelines with a diameter larger than DN200. This post was last edited by 19751107w on 2007-12-20 at 16:44
The operating temperature varies depending on the sealing material used
I’m responding to everyone: this valve is used as a pressure tapping valve for orifice plates on steam pipelines with a pressure of 3.5 MPa. The pipe diameter is DN15, the operating temperature of the steam is 420°C, and the operating pressure is 3.5 MPa. Are these conditions suitable for using this valve? If not, what specification of valve should be chosen?
Use a stop valve! The metal sealing surface should be 1Cr13, and the gasket should be a 304+graphite wound gasket! Ball valves are not suitable for this purpose!
Then the valve below should be fine, right? It’s a ball valve with a DN15 size; the valve body is made of A182-F11 material, with a pressure rating of PN10.0. The seat sealing surface is made of STELLITE, as is the ball’s sealing surface. The valve stem is made of 13%Cr material, and the stem packing consists of 304 stainless steel wire along with flexible graphite. This valve should function properly at 420°C, right?
As a orifice plate pressure tapping valve, it is feasible according to the conditions specified on the 12th floor. :)
It is possible to use ball valves, but it is not economical. Metal hard-sealed ball valves with a DN15 size are definitely more expensive than gate valves or stop valves. Moreover, the sealing mechanism of ball valves is more complex compared to that of gate valves and stop valves; in addition to considering the sealing surface of the valve seat, it is also necessary to take into account the sealing at the valve stem. Ball valves do not have a metal back-seal at the valve stem like gate valves and stop valves. As for sampling valves, stop valves allow for emptying after sampling, while some fluid remains in the cavity of a ball valve. In my opinion, it is more appropriate to choose stop valves with socket weld connections.
The sampling valve also uses needle valves, graphite wound gaskets, and specialty-grade double-headed stud nuts
500 degrees should be fine