GB807523A - Improvements relating to fire-extinguishing apparatus - Google Patents

Abstract

807,523. Fire-extinguishing. PYRENE CO. Ltd. Feb. 8, 1956 [Feb. 10, 1955], No 4054/55. Class 47 In a powder extinguisher, compressed gas from a cylinder 5 passes through a pipe 9 to a pressure operated diverting valve 6 which initially directs the gas along a pipe 10, through a chamber 11 in an isolating valve 7 and down a dip tube 3 into the container 1 where the gas disturbs the powder contained therein When a predetermined pressure is reached in the container 1 the valve 6 operates to divert the gas to two different points through pipes 21, 22 namely, to a flow control device 8 through which the gas thereafter flows to the container, and to the isolating valve 7 which is thereby operated, causing a valve member 15 to open a port 18 through which powder forced up the dip tube 3 by the pressure in the container may pass to a discharge hose 4. The flow control device 8 includes an orifice 26 of a size so correlated with that of the discharge tube and any other passage through which the gas flows, that the pressure in the container falls continuously during discharge. The flow control device also includes a valve which stops entry of the gas into the container in response to a predetermined pressure reached in the container during operation. A manually controlled by-pass valve 47, downstream of the isolating valve 7, enables the hose to be cleared of powder, or the pressure in the container to be released without expelling powder. Specifications 737,581 and 807,088 are referred to.