Busted steam check valve of pressur

[RORCULLO123]

Busted steam check valve of pressure boiler drum....

Our company has 4 coal fired boiler and two fuel fired boiler. We are required to maintain 1 MPa to maintain the production operate in a good condition.we operate 2 boler at a time to avail these requirement.the connection of the two boiler are in a parallel manner.

at time that we operate the bunker and the other boiler the cheked valve head of bunker side was explode...

the question is, what is the most probable cause of explosion.Is the connection of the boilers are critical if they run not simulteneiously? What are the tips to avoid this kind of sequeces if there is ?Is pressure hammer exist, that is why the pressure at the bunker exceed to the check valve design pressure limit?

thanks....ROCULLO123

 

[TBP]

I'd say waterhammer as a result of water being trapped between the closed stop & check, and the closed stop valve at the header. There should be a free-blow drain between these valves, as well as a steam trap to prevent any accumulation of water in this short section of pipe. Even with relatively low pressure in the boiler, and/or the header, if either valve is opened - no matter how slowly - you can get condensation induced waterhammer. A steam bubble forms in the relatively cool condensate, then instantly collapses. The resulting pressure spike as water rushes in to fill this vacuum can be spectacular. Take a look at Wayne Kirsner's work at

http://www.kirsner.org

He has a series of photographs of valve and line failures, as well as articles he written on this phenomenon.