Fusible Plug

Fusible Plug is a fitting used in Steam Boilers to enhance the safety during operation. It’s working depends upon the water level in the Boiler shell. A fusible Plug is a threaded metallic cylindrical object, with a tapered hole in it which goes through its entire length. It is usually of brass, bronze or even gunmetal. In a smoke tube steam boiler, it is fitted on the front tube sheet, just above the tubes (used for flue gas flow) arrangement but below the perforated feed line inside the shell.