We are using plastic material for o

[fujit]

We are using plastic material for our valve seat insert and want to confirm that the material is good for the pressure-temperature rating of the valve. Could i get advice on the stress mode to consider for this purpose -
1. Stress due to the seat being compressed to the ball due to pressure
2. Shear stress caused by friction between the seat and the ball while the ball is turning
3. Bending and/or shear stress as the pressure is trying to force past the seat insert

Direct advice will be appreciated as will reference to some design guide.

 

The first one to ask is the valve manufacturer.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[btrueblood]

1 2 and 3 are all important for different reasons. Wear, erosion, creep/relaxation, and degradation of the polymer due to material/temperature effects also need to be considered.