Pressure regulating flap for fire protection springs shut as spring solder fuses at specified temperature thus balancing temperatures across rooms to maintain door function.

摘要

Pressure regulating is a leg spring on the flap blade (3) held in tension by a fusible solder (8) so as to release the spring at pre-set ambient temperature and so lock the flap blade. The flap is locked at 72 deg C and the pressure gradient is adjusted continuously and can be balanced out under normal conditions, i.e. without fire, this without affecting fire protection. The entire equipment including fire protection is built into a sleeve (1) housed in an inbuilt sleeve to compensate for wall thickness. The spring is only released in a range 5 to 80 deg C, specifically at 72 deg C.