Air type fusible plugs are used to protect compressed air systems from the risk of an explosion occurring due to ignition of oil vapours in compressors and compressed air systems.

Boiler type fusible plugs are used to protect solid fuel fired boilers from being operated at dangerously low water levels.

Both plugs are designed to operate when high temperatures occur, thereby reducing pressure and providing audible warning of dangerous conditions.

They are made of brass or bronze construction with a centrally located fusible disc. When fusion occurs, air pressure ejects the molten disc which is retained by a vented cap.

The fusing temperature of the disc is chosen to suit working conditions. When specially ordered, stainless steel and high pressure versions of both FP Valves can be supplied.

Air type Fusible plugs should be fitted vertically on the underside of the pipe between the compressor and the receiver, as close as possible to the compressor.

The DN10 size should be used for pipe bores up to DN50, the DN15 size for larger bores.

Fusible Plugs used on vessels are normally fitted to the top of the vessel being protected. Plugs should be checked in service every year and the fusible disc cleaned or replaced as necessary.

Special precautions must be taken when using fusible plugs, especially for hot water & steam applications. Please contact or technical team for details.

Our fusible plugs are made to BS1123: 2006 and must not be used as the primary safety device in any pressure system.