NITROGEN CRYOGENIC PLANT FOR FIRE EXTINGUISHMENT IN CLOSED OBJECTS Russian patent published in 2007 - IPC A62C35/00 

FIELD: fire-fighting, particularly devices using inert gas for fire-extinguishment in space to be protected.

SUBSTANCE: plant comprises cryogenic vessel with liquid nitrogen, gas discharge means, fire-extinguishant supply pipeline, controllable valve, at least one detector and evaporator arranged outside the cryogenic vessel. The evaporator is communicated with lower vessel part filled with liquid nitrogen by means of lower evaporator end and with cryogenic vessel head space by upper end thereof. Controllable valve is installed in initial evaporator section. Fire-extinguishant supply pipeline is made as cryogenic pipeline provided with controllable valve. One cryogenic pipeline end is communicated with cryogenic vessel area filled with liquid nitrogen. Another end thereof has fire detector linked to controllable valves of pipeline and evaporator. Fire detector is made as temperature sensor or smoke sensor or gas sensor. Temperature sensor may be made as bimetal ring formed as annular constant magnet covered with ferromagnetic shell of material with Curie point close to liquid nitrogen boiling temperature. Bimetal ring is thermally isolated from coupling body. Magnetically operated contact, namely reed switch, is built in coupling body. Controllable valve is made as heat-sensitive valve and comprises body, inlet and outlet popes, slide and seat. Outlet pipe is diffuser. The slide is connected to working heat-sensitive spring made of shape-memory material and secured to valve body. The plant may have control panel. The cryogenic vessel may be conveyed, for instance by means of wheel pair.

EFFECT: increased efficiency by optimal inert gas stock usage due to fire-extinguishant phase composition control by regulation of supplied cryogenic liquid flow rate via cryogenic pipeline.

6 cl, 2 dwg