Steam traps Common problems

Undersized condensate return-lines create one of the most common problems encountered with process steam traps. Hot condensate passing through a trap orifice loses pressure, which lowers the enthalpy of the condensate. This enthalpy change causes some of the condensate to flash into steam. The volume of the resulting two-phase mixture is usually many times that of the upstream condensate. 

It is important to know that steam traps should not be sized based on pipe size. A common problem is poorly sized traps that cause premature failure through excessive cycles and wear on internal parts as well as excessive steam leaks. Therefore, steam traps are selected primarily on duty second, on duty variation for transient cases and third, on equipment requirement (Kenny, 1989). Proper installation and maintenance together with regular vendor service can maintain good steam trap performance and long life. 

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