Valve selection issue
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Valve selection issue: For the DN50 ball valve used in the discharge circulation of the separator at the bottom of our MVR evaporator, a lined version can last for 10 days, while a carbon steel version lasts only 4 days. The operating temperature is 200 degrees, and the medium is high-concentration brine. In the case of a lined ball valve, damage occurs due to deformation and peeling of the fluorine coating, while the outer carbon steel body gets corroded and perforated. However, with the same medium, under the same operating conditions, and using the same type of valve from the same manufacturer, it functions properly in other locations; but here, the valve is often left in a partially open position, which leads to severe erosion. What should be done? How much does a DN50 fluorinated lining ball valve cost? We need to replace it every 10 days, and during replacement, production has to be stopped and the material inside has to be emptied
It’s probably the sealing material that’s damaged
Choose a corrosion-resistant material; for the type of valve, use a globe valve or a control valve. Stainless steel, such as 316L, or high-nickel materials starting with 9 can be considered. If that doesn’t work, then alloys will have to be used
Have the procurement department find reliable manufacturers that can produce corrosion-resistant valves, have them supply the products, communicate with them, and encourage them to continuously improve their processes – this will solve the problem.
Fluorinated-lined valves come in F4, F46, and PFA types; among these, PFA has the highest temperature resistance, up to 180°. The temperature of your medium exceeds the maximum tolerance of these lined valves, so they will break down after just a few days of use. If you need valves that are resistant to corrosion and high temperatures, don’t worry about the cost. Feel free to contact me at 18721019856 if you need any assistance
Why is the temperature so high? Isn’t this just causing discomfort for oneself?
Every product has its appropriate application scenarios; if you use it outside those scenarios, you need to either improve the manufacturing process or replace it with a valve that is suitable for that use case!
By using imported PFA, it is possible to withstand temperatures up to 220 degrees; using RPTFE for the valve seat should yield better results
Spanish TTV valves – I can meet all your requirements; contact me. Cao Yuhui 15956378939
I think it’s time to switch to a different alloy, one based on nickel or even better, and go with a hard-seal version