Who can tell me advantages and disadvantages with stellite or tungsten carbide hardfacing?
Item is a trunnion mounted ball valve, hardfacing on ball and seats.
AKA milanflyer@ http://www.valvezone.com
If you buy a lined butterfly valve according to API 609 cat A, the valve shall be tested according to API 598.
API 598 say that pressure testing shall be done before painting.
But this makes no sense for a lined valve with the liner as sealing surface against the flanges of the pipes.
If you get...
If I have understood this correctly, in reverse acting gate valves, you pull the plug up to close the valve. Gate down = open valve.
What are the benefits of such a design?
In what kind of aplications is this valve used?
