Stellite steam erosion

[lgracey]

Please relate any experience on damage mechanisms to Stellite 6 on valve seats and plugs if the valves are passing subcooled water at 300 degrees C and 155bar? The downstream side of the valve is at STP thus the liquid flashes to steam. The environment is typical to a nuclear 900MW PWR reactor primary circuit Power Operated Relief Valve.

 

[hacksaw]

you need to be more specific about the valve you are using, it is not a service that merits a generic answer

 

[Metalguy]

While Stellite 6 and other numbers are very erosion-resistant, they sure aren't erosion-proof. Your conditions are severe.

BTW, since you're dealing with the primary-side, don't you have concerns with cobalt-reduction in valves (for radiation reduction)?