The Basic Functions of a Steam Trap and Common Steam Trap Applications

Durable steam traps came into widespread use at the height of the Industrial Revolution. Late 19th century industries were dominated by steam, which was used to generate power, perform work, and deliver heat to industrial process systems. Due to the widespread use of mechanical equipment today, steam traps—from manufacturers like Armstrong, Barnes & Jones, Spence, Spirax Sarco, and Mepco—are used to provide thermal efficiency, while effectively removing condensate to prevent mechanical damage inside process equipment, turbines, and piping.   

An article written by Terry Acers, which appeared in Valve Magazine, gives us more information about the functions of steam traps:  

“Steam traps are automatic valves that differentiate between steam and condensate. Their primary function is to discharge condensate from ­collection points in distribution piping and process equipment, and then close tightly on steam to prevent unnecessary energy loss. As the steam space in most systems is full of air at ambient temperatures, a secondary function is to vent air during startup.”

When steam releases heat energy in the heat exchanger while boiling hot water, or from any other process application, the steam reverts back to water. This water, which is technically known as condensate, must be separated from the steam and removed from the system to avoid backing up the system. Other non-condensable gasses, such as carbon dioxide, must be separated from the steam and removed from the system to facilitate steam flow and proper heat transfer, and to prevent components from corroding.

Listed below are the general application categories for steam traps.

Drip Applications

This process involves removing the condensate that forms in steam lines when steam loses heat energy due to radiation losses. Drip traps don’t require large condensate capacities and don’t necessarily need to discharge large amounts of air. This type of application is by far the most common one, and inverted bucket traps are often used for drip trap applications because of their ability to handle large amounts of dirt.

Process Applications

This type of application is used to remove condensate and air directly from the heat exchanger. Process trap applications require a higher condensate handling capacity and must discharge larger amounts of air. The most common trap choices for process applications are float and thermostatic traps, as well as thermostatic traps.

Tracing Applications

Steam tracing helps increase a product’s temperature via jacketed pipes or tubing filled with steam. A common tracing application involves wrapping high viscosity oil pipelines in steam tubing to lower the viscosity of the oil. An efficient steam trap—which can be ordered from reputable suppliers like A.L.B. Industrial Supplies Inc.—needs to be installed at the end of the steam tubing to remove unwanted condensate.

(Article Information and Image from The Mighty Steam Trap; Valve Magazine)