Problem in cyclone separator purge valve

[manojhere99]

I have a problem with cyclone separator purge valve which is operating in hydro power station. At cyclone drain, two valves are located one is manual drain & another is motorised valve. During purging operation manual valve which is always open is working fine whereas motorised valve is getting damaged. Earlier both valve have same material, when we faced problem of motorised valve damage. We changed motorised valve material to higher grade then we found that performance has slightly improved but still motorised valve get damaged whereas there is no problem with manual valve.

What can be the reason for failure of MO valve & possible solution.
One reason I think is that valve size may not be sufficient & during the time when valve is opening/closing, velocity is increasing or decreasing & creating failure. So we are thinking to increase valve size. However I am not very sure about this solution & what size I should select.

 

[kevplumb]

I have a problem with cyclone separator purge valve which is operating in hydro power station.

hardly DIY then

 

[WDIK]

is this a flowmech vortex scrubber?

or similar

as for the rest more info required