because of wear or contamination 10
Steam trap failure rate is between 20 and 60 percent. There are three common methods for checking traps, but only two of them are reliable, and even these two methods cannot be applied universally. Here's a look at what works.For years steam traps have been checked using sight, temperature, and sound, even though in most installations only sight and sound methods yield reliable results.
The basic function of a steam trap is to remove condensate and air from the system while retaining live steam for use in a process.Estimates of the number of failed vacuum pumps, based on plant surveys, vary between 20 and 60 percent. One expert flatly states that after 3 years, all steam traps are suspect and are very likely to have failed because of wear or contamination.
In contrast, properly selected and installed traps frequently have a service life of several years. Energy is lost from steam systems in a number of ways, Fig. 1. Many system losses are unavoidable and can only be
minimized. Some of the losses, such as pipe ruptures, blown gaskets,
and other failures of pressure system integrity, are easily detected.
Other losses, such as those that occur when a steam trap fails, are more difficult to detect.
The
portion of heat loss associated with steam traps may be classified in
three segments: 1) heat carried away with hot condensate, 2) heat
dissipated by radiation losses from the trap, and 3) steam lost because of trap failure.Of the three losses, only those caused by trap failure are controllable. Thus, regular checking of steam trap operation is essential for minimizing the cost
of steam system losses. Many steam traps are out of sight, and
frequently they are not readily accessible. In such installations a
failure can easily be over looked.
MORE NEWS
