Automatic cut off system for fluid circuit - includes shut off valve fitted in fluid circuit that is operated by linear actuator via rod with thermal fuse that operates in case of fire

The unit consists of a shut off valve (2) fitted in a fluid circuit that is operated by a linear actuator (3) via a rod (33). The actuator is a single acting spring return (32) jack that hold the valve (2) open when fed from a pressure source (S). In this feed line is inserted a three way valve (7) that is kept normally in the feed position by a wire (73, 74) whose one end is fitted to the control lever of the valve (7) and whose other end is fitted to an anchor point (P). In this wire is a thermal fuse which melts at a given temperature thus allowing the valve (7) to change over to block the feed to the actuator and discharging the pressure chamber (C) in the actuator to atmosphere. Use/Advantage - As an automatic cut off system for a fluid circuit with an industrial application which operates independently in case of a fire. Dispositif pour couper automatiquement un circuit (1) de fluide en cas d'incendie comportant une vanne (2) actionnée par des moyens moteurs (3) sur lesquels agissent des moyens (71) sensibles à la température pour provoquer la fermeture de la vanne (2) en cas d'élévation de la température au-delà d'une limite prédéterminée.