Steam Traps - Care and Maintenance

Steam Traps - Care and Maintenance 

Steam traps have play a very important role in steam distribution systems. The service performed by steam traps is primarily to discharge condensate. Normally a steam trap can be easily and quickly selected by considering only the average operating conditions. However, an exact analysis of these conditions will give the proper data necessary for selecting the type and size for greater savings and proper plant operation. After the careful selection of the steam trap, it must be properly installed, tested, periodically inspected, cleaned and maintained to keep it operating efficiently.

Traps need cleaning periodically. A simple way to prevent dirt from entering is to drop a short length of pipe vertically below the supply to the trap (called a dirt leg) which can be cleaned easily and frequently.

Traps can be seriously damaged by scale or pipe comings in lines. A good practice is to install strainers ahead of the traps which should be inspected and cleaned frequently.

Traps are subject to severe wear if steam blows through continuously. They should be inspected for worn valve parts or a change in operating conditions.

When a steam trap fails to discharge, inspect the heating system and be certain that all units are drained with separate traps, thus guarding against short circuiting, loss of energy, and reduction of operating efficiency.

Traps operating under high pressure or superheated steam are often insulated in a manner similar to adjacent pipe lines. In such instances, they shall be fitted with dirt pockets, test valves, and drains.

Steam traps installed in areas exposed to climatic conditions will lose heat if not insulated and may freeze unless adequately protected. Discharge lines should be short and self draining and traps should be fitted with a drain tapping and valves.

Steam traps handling large volumes of air require more frequent inspection and proper venting for efficient operation. Vents shall be used to avoid air binding and ensure positive drainage. Gauge glasses shall be kept in proper repair, for they indicate whether or not the trap is working. Periodic cleaning and gauge glass replacement shall be considered as a high priority in the maintenance of steam traps.

All steam traps require protection from corrosion to prevent unnecessary deterioration. All valves, joints, and gaskets should be kept tight to avoid steam leakage and ultimate energy losses. For continuous and efficient operation. steam traps require periodic inspection and maintenance for purposes of eliminating foreign matter and obstructions in supply and discharge lines. Each steam trap at an assigned work station should be inspected as specified by the preventive maintenance program.