Regulating valve in the high, low temperature valve does not work the normal solution (5 methods)
1) uniform line swelling decreased two-seat valve leakage method
Two-seat valve in the normal temperature test, the leakage is not too large. However, an input high temperature leakage volume soared. This is because the seat is fixed on the valve seat sealing surface of linear expansion linear and valve sealing surface is not a double expansion caused by a DN50. If the valve seat, valve core is made of stainless steel, valve for carbon steel, used in F at room temperature 70 degrees in the sealing surface of the valve seat and valve, expansion of 0.06mm sealing surface line, an increase of leakage is more than 10 times. The solution:
The selection of the valve body and the valve core are made of the same material, the stainless steel valve. But stainless steel valve than carbon steel valve high price by more than 3 times. From the perspective of economy should be considered;
The selection of the sleeve valve replaced, due to the sealing surface of the sleeve, the sleeve and the valve plug is the same material.
2) the valve seat sealing welding method
When the temperature up to 750 ° F, the seat of threaded connection caused by leakage in the surface and the thread seal is connected with the valve, which can be threaded erosion, dangerous seat falling, encounter this kind of failure, should think of seal welding of the valve seat, to prevent loosening and shedding.
3) lining welding method
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