Steam Traps

Steam traps are analogous to motor vehicles in that each has a single underlying purpose but is available in a wide variety of models and options. Selecting the correct model depends on user needs and preferences. In selecting the right trap a user must think hard about the priority of his needs. While efficiency and reliability may seem obvious requirements, other criteria (such as responsiveness to changing pressures and condensate flow rates, installation flexibility, ease of maintenance, and troubleshooting) are more judgmental. When all of these issues are considered, steam trap selection becomes a matter requiring thoughtful evaluation. At the least, a wrong selection means a savings opportunity missed; – at the worst, it can mean a costly disruption of production.

 

Industrial steam traps can be divided into two major groups: (1) traps designed for draining process equipment such as tire presses, drying rolls, air heaters, and heat exchangers (often referred to as process traps); (2) traps designed for draining steam mains or tracing systems. The latter serve as a protection function and are sometimes referred to as protection traps. Protection services, such as steam main drips and tracer heating, are by a wide margin the most common trap application. They generally see very light condensate loads, often less than 50 pounds per hour. Process traps are generally designed for condensate loads of several hundred pounds per hour to several thousand pounds per hour.

The three types are:

• Thermodynamic traps: traps that are actuated by the principles of thermodynamics and fluid dynamics.
• Mechanical traps: traps that are actuated by a float, responding to changes in condensate level.
• Thermostatic traps: traps that are actuated by temperature-sensitive devices, responding to changes in condensate temperature.