Definition - What does Steam Trap mean?
A steam trap is a valve that is automated to differentiate between steam and condensate, holding back the steam while discharging the condensate under different pressures. They are often used as a common measure to prevent corrosion in pipes by removing condensate; thereby keeping the steam dry.
Corrosionpedia explains Steam Trap
The purpose of the steam trap is to close, just like an automatic valve, in the presence of steam and selectively remove condensate. A steam trap dislodges condensates and non-condensable gases for the purpose of producing dry steam. Steam vessel or pipe systems are incomplete without a steam trap. The trap is vital on a condensate line because it connects steam usage with condensate return.
The amount of condensate that traps can process varies considerably. Condensate can be displaced at several temperatures, such as at steam temperature or below steam temperature. This variation applies to discharge pressures as well. Steam traps are capable of operation anywhere from a vacuum to well over 100 bars in pressure. Therefore, a wide range of steam traps are commercially available to suit different operating requirements of a pipe or vessel. Steam traps work best when their characteristics are matched to that of the application.