Fusible Plug – Two-Piece Design - IBR Approved

A fusible plug is a crucial safety device fitted on the crown of the firebox or boiler shell, designed to protect the boiler against accidents caused by low water levels. The two piece design fusible plug is manufactured as a robust, one-body construction, ensuring high reliability and long service life. It contains a fusible alloy core with a predetermined melting point (typically around 450°F–550°F / 232°C–288°C). When the water level falls below the safe limit and the plug is exposed to steam or fire instead of water, the fusible alloy melts. This allows steam to escape with an audible warning, extinguishing the fire and preventing overheating or boiler explosion. The single piece design eliminates the need for multiple threaded parts, reducing chances of leakage, misalignment, and mechanical failure. This makes it ideal for high-pressure steam boilers, process heaters, and IBR-certified applications.