Fire sprinkler system for coal conveyor - has differential pressure valve which operates when ampoule breaks and stops automatically after preset time

摘要

The sprinkler system is installed near the drive end of a coal conveyor belt and operates when a fire occurs. It comprises a differential pressure valve (2), the incoming water (1) being applied to two different sized heads. The smaller (13) is held closed by the larger (12). When heat breaks an ampoule (6), the pressure drops on the larger head, the valve opens and the sprinklers (7) operate. A plunger (8) is extended to activate an alarm (9). A bleed (10) eventually fills a tank (4) enclosing the system and a float valve (3, 5) is closed in the ampoule line. This re-establishes the pressure differential and the system stops automatically.