The reason why the stainless steel screw and the stainless steel nut cannot be used together is that the stainless steel bolt and the stainless steel nut are often sewn after being fastened in the assembly of the low temperature pipe flange, and it is difficult to remove it again.

Workaround:

1. Cryogenic treatment. Insulate the parts into the cryogenic liquid nitrogen tank for a certain period of time to reduce the deformation caused by the temperature difference and metallographic structure, thereby increasing the valve at a low level

A treatment for the sealing performance of warm time;

2. The nut is directly changed to copper nut;

3. Using anti-bite agent;

4. Apply grease to the screw before tightening the nut.