Three Types of Steam Traps and Their Applications

We defined Steam Traps in the previous EEE Boilerman blog posts: Thermostatic Steam Traps and Thermodynamic Steam Traps. For a quick review, refer to the blog from Uni Klinger Limited, an equipment manufacturer in India, that states, “Steam traps are used to trap steam & allow discharge of condensates and non-condensable gases with a negligible consumption or loss of live steam from steam piping, steam tracers, and in steam-consuming equipment.”

Types of Steam Traps

The three main types of steam traps are mechanical, thermostatic, and thermodynamic. Each operates differently from the other. Mechanical steam traps “-operate according to the difference of the density of steam and condensate, which allows the condensate to flow,” states an information page from Ayvaz, a leading manufacturer of steam equipment. Float, Free Float, and Bucket Steam Traps fall under the mechanical steam trap category.

The Uni Klinger blog titled Different Types of Steam Traps and its Applications states, “Thermostatic Stream Traps remove condensate through the temperature difference of steam & liquid phase.” Liquid Expansion, Balance Pressurized, Bi-Metallic, and Bellowed steam traps are considered thermostatic.

The same post explains that thermodynamic traps operate “-on the dynamic principals of steam & condensate (Velocity difference) and use of Bernoulli’s principle.” You can visit https://bit.ly/483VZQZ to learn more about Bernoulli’s Principle. The two types of thermodynamic traps are Disc-type and Steam Jacketed steam traps. Again, please look through previous Engineered Energy Equipment blogs for a detailed look at thermostatic and thermodynamic steam traps.

Steam Trap Applications

Mechanical Steam Traps

An article about Mechanical Steam Traps posted by Spirax Sarco, a steam equipment manufacturer that advises companies, talks about ball float steam traps, saying, “It will discharge condensate as soon as it is formed, regardless of changes in steam pressure.” The same article claims these steam traps are “-the first choice for applications where the rate of heat transfer is high for the area of heating surface available.” The same webpage states, “The inverted bucket steam trap can… withstand high pressures.” Inverted bucket traps are also safer on applications requiring open failure mode, like turbine drains.

Thermostatic Steam Traps

“The liquid expansion steam trap may be usefully employed as a ‘shutdown drain trap,” according to the Thermostatic Steam Traps information page created by Spirax Sarco. Small and light but can carry a large load, modern balanced pressure steam traps have “considerable resistance to damage from waterhammer, superheat and corrosion,” reports the same Spirax Sarco article. Another steam trap that is compact but has a large capacity, the Bi-Metallic trap, is “-constructed using two strips of dissimilar metals welded together into one element. The element deflects when heated.” The article continues, saying “-this type of steam trap will not freeze up when working in an exposed position,” and “-are designed in such a way that they will not receive any damage even if freezing does occur.”

Thermodynamic Steam Traps

The Spirax Sarco page about Thermodynamic Steam Traps informs readers that these traps are:

Simple, robust, and reliable and can operate up to very high temperatures and pressures
Able to operate across their entire working range without any adjustment or change of internals
Not damaged by freezing and are unlikely to freeze if installed with the disc in a vertical plane
Easy to test because an audible “click” occurs as it opens and closes

Our boiler professionals recommend equipment manufactured by Sterlco or Sterling. Although researching parts to purchase for the steam boiler in your specific situation is brilliant, it is always beneficial to get an expert opinion before making such a significant decision. Don’t hesitate to contact our specialists to confidently choose the type of steam trap you need!

References