GB1265141A - - Google Patents

Abstract

1,265,141. Automatic sprinkler systems for load bearing metal framework. NATIONAL RESEARCH DEVELOPMENT CORP. 17 Feb., 1969 [17 Nov., 1967]. No. 52375/67. Heading A5A. [Also in Divisions E1 and E2] A load-bearing metal frame structure heated on the occurence of a fire is cooled by vapourisation of a cooling fluid exposed to the atmosphere whilst in contact with the structure, the fluid being passed along ducting provided by the structure or being directed substantially exclusively at the structure from separate ducting. In one embodiment box beams 14 Fig. 12 and an upright 10, having apertures 202 to provide exposure to the atmosphere, are supplied with cooling fluid from a separate conduit 22 (not shown), under the control of valve means which opens at a predetermined elevated temperature which is less than the boiling point of the cooling fluid. In a modification the girders 14 themselves substantially provide the ducting for the flow of fluid. In another embodiment in which the girders themselves function as ducting, apertures 41 Fig. 6 therein, and baffles 40 are provided to direct a flow of cooling fluid over the exterior surface of the uprights 10D. In Fig. 8, separate ducting 130, 131, 132, 133 contains apertures which direct cooling fluid against the webs of I beams forming the framework, and open-ended branch pipes direct cooling fluid on to the uprights. Several modifications of these embodiments are also described. The fluid may be supplied under the control of a manually operated valve or supplied from an external source by a fire brigade. The system of the invention can use the same supply of cooling fluid as a conventional sprinkler system.