substrate deformation of WC coating in gate valve

[ehsan]

Hi
Our customer that produce gate valve say that after several working opening/closing of gate valves we have some deformation of substrate of WC coating on the gate.this deformation is effect of seat on the coating substrate of gates(to be crushed). base material of gates in this kind is 4130 AISI with 25 HRC .is this possible that we have some heat treatment on gates before coating for solve this problem?(such as nitriding or ...)

[Gordon]

Hi Ehsan

Not sure if surface treatment will be the answer here, I think you will need to consider changing to a stronger base material.

[Asiaf]

Hi,

The conversation is rather old ! Hope the problem is solved , The reason I joined this site is to say that I have experience of exactly the same problem and we solved it before so I,m ready to co-operate in this case !

Overall direction of the history of covnersations is in correct directions but some fundumental steps are incorrect so it needs some changes from the base up to end stage of filling the face with epoxy.

Our main activity was repairing of shear gate valves of Cameron brand which is used in oil drilling facilities. 5000 PSI is rather low pressure for such application while 15000 psi is some how normal pressure.

Regards
Asiaf