Steam Trap Installation Guidelines

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This post was last edited by Watt Energy Saving on 2020-6-6 22:20 Installation Guidelines for Steam Traps Steam traps need to be installed correctly in accordance with the detailed installation manual provided by the supplier, and all information on the correct installation of the trap. What should be paid attention to in a good trap application. It must be noted that the system pressure level cannot exceed the maximum allowable pressure and temperature (PMA and TMA) marked on the valve body. The actual working principle cannot exceed the designed maximum operating pressure (PMO) of the trap, otherwise it will be difficult to ensure safe and effective operation. To ensure safe and reliable isolation, shut-off valves (including relief valves, shut-off valves, inspection valves, etc.) should be used during maintenance. Depending on the application equipment, bellows-sealed globe valves or ball valves can be selected. If possible, it is recommended to use a trap directly. All steam traps have small discharge holes and movable parts. If impurities, welding slag, iron filings, etc. in the pipeline enter the trap, it will easily cause blockage, resulting in leakage or damage to the trap. Therefore, it is necessary to install a Watt energy-saving 10 mesh-30 mesh Y-shaped filter upstream of the trap. The Watt inverted bucket trap is designed with a built-in Y-shaped filter, eliminating the need to install a separate filter. However, for some traps with built-in baffle filters, it is still recommended to install a separate Y-shaped filter for easy cleaning. A trap device should be installed upstream of the steam trap to facilitate monitoring and detecting trap failure or water accumulation in the equipment. In some applications, a sight glass is installed downstream of the trap, but this is becoming increasingly rare. The sight glass should be installed at least one meter downstream from the spray trap. When there is back pressure in the condensate drain pipe, a check valve should be installed downstream of the steam trap to prevent the inlet pressure from reducing or water accumulation in the steam space during shutdown. Watt's energy-saving experience suggests that the check valve should also be installed one meter downstream from the spray trap. It is not recommended to use lift-type check valves and other models that require higher opening pressure. Forgetting to close the bypass can result in steam leaks or trap failure, and may increase condensate recovery pipe pressure. Therefore, we generally do not recommend installing hydrophobic bypasses. If it must be installed, it is recommended to install a ball valve with better sealing performance. The steam trap should be installed lower than the steam system, and there should be a small-diameter downpipe about 150mm upstream of the trap. Otherwise, the sealing bladder/component of the pressure-balanced trap and bimetallic trap cannot be controlled by the condensate temperature at low load, which will lead to misoperation of the trap. For steam traps connected by welding, arc welding should be used because the internal parts do not need to be removed when connecting using arc welding. Using other welding methods may deform the valve body or damage internal components. Care should be taken to ensure that the steam trap is installed in the correct direction and that the steam trap should be installed in the correct flow direction as shown on the trap body. Especially for mechanical steam traps with vertical lifting mechanisms (such as float traps and inverted bucket traps). If installed in the incorrect direction, trap wear, failure, and steam loss may result. Static steam traps cannot be installed upside down and head down. At low loads, such head down installation will cause the sealing bag or components to be immersed in cold stagnant condensate, which will cause the trap to open too wide and increase the displacement, which in turn will try to close the trap. These two opposing effects can cause the trap to malfunction. Watt's energy-saving experience shows that impurities such as welding slag in the pipeline can easily enter the valve cap and affect the normal operation of the sealing bag/component. Pressure-balanced traps and bimetallic traps cannot be installed sideways, otherwise the sealing bag/component will be half immersed in condensate and half exposed to steam, resulting in misoperation of the trap. . In order to save costs, some customers use one trap to drain the condensate from several devices, which is called group trap. However, in fact, due to the different working pressures of each equipment, water accumulation in the system will occur. Therefore, Watt Energy Saver recommends that a separate drainage system should be used for each piece of equipment.