GB839255A - Improvements in fire and explosion protection systems - Google Patents

Abstract

839,255. Explosion suppressing and fire extinguishing in tanks. GRAVINER MANUFACTURING CO. Ltd., and WILKINSON SWORD Ltd. Oct. 18, 1957 [Oct.. 22, 1956], No 32047/56. Class 47 For suppressing explosions or extinguishing fires in a closed storage tank for explosive liquids, one or more elongated frangible containers of explosion suppressant liquid are provided to extend vertically from adjacent a lower surface of the tank to adjacent an upper surface of the tank, each container having an electrically ignitable explosive charge therein, and incipient explosion detection means are provided for igniting at least one of the charges upon the onset of an incipient explosion. In Fig. 1 a static tank 10 is provided with a number of vertical columns each comprising several contain-- ers 12 of the general form described in Specification 799,526. Incipient explosion detectors 11 are situated above the maximum fuel level in the tank 10, and these detectors may be pressure-rate-ofrise detectors of the kind described in Specifications 643,188 or 719,622 and 786,871 or may be of photo-electric form as described in Specification 749,597. The detection means 11 are connected to the igniters of the explosive charges in the containers 12 via an electric power source 13 which may be of the form described in Specification 786,873. Float or diaphragm actuated level switches 14 are connected to short circuit current or to open circuit the igniters of the explosive charges in the containers 12 so that ignition is prevented of those containers 12 which are wholly or partly submerged in the liquid contents of the tank 10. In Fig. 4, the tank 21 of a mobile fuel bowser or tanker is provided with two incipient explosion detectors 20, mounted at opposite ends, and connected so that both must be operated in order to effect distribution of suppressant. In this way, movement of the fuel to one end of the container due to movement of the tank will not cause inadvertent operation. The suppressors 22 may be of sufficient length for only one to be used in each of three compartments defined by apertured baffles 21a which limit fuel movements. The suppressors may be similar to that described in Specification 799,526, or as shown in Fig. 6, may consist of a glass envelope 22a containing an explosive charge 23 of chord form supported in a glass tube 24 and arranged to be ignited by an electrically fired detonator 25. The envelope 22a is held against a mounting plate 27 by a clamp 28 and bolts 29. Supports 31 are provided for the lower end of each suppressor 22.