POWDER FIRE EXTINGUISHING METHOD AND DEVICE Russian patent published in 2005 - IPC

FIELD: fire-fighting, particularly unmanned powder systems for surface or volumetric extinguishing of class A, B and C fires and electric equipment with voltage up to 1000 V in coal, metal mining, chemical, oil and atomic industries, in transport and in civil, industrial and residential buildings, offices and garages.

SUBSTANCE: method involves delivering previously-aerated gas-and-powder mixture including fire extinguishing powder and retarding gas into volume or to surface to be protected, wherein the delivering is performed with the use of high-pressure containers with spraying nozzles uniformly distributed over the volume or the surface to be protected. Pressure is selected to overcome fire heat depression with rate exceeding fire heat flow rate; performing free gas-and-powder mixture flow into volume or to surface to be protected. Fire-extinguishing device comprises at least two containers with fire-extinguishing powder. Each container is provided with spraying nozzles with opening pressure regulation and connected to common retarding gas source through powder aerator formed as radial tubes with orifices and valves. Containers are united with retarding gas source through tubular channel into common pipeline. Vents leading from pipeline to each container are provided with shutoff valves connected with holders for pipeline securing. Each shutoff valve comprises body with cylindrical inlet connection pipe at least partly arranged inside the body and installed coaxial thereto. Inlet connection pipe has closed bottom. Cylindrical outlet connection pipe slides over the body and is brought into contact with the body by means of sealing member arranged in annular groove made in lower part thereof. Lower sealing member end is to be engaged with inner annular extension of lower body part by outer annular extension thereof to prevent axial displacement of outlet connection pipe beyond the body. Connection pipes are provided with side cuts communicating one to another through inner volume of shutoff valve body. Outlet connection pipe may move together with container attached thereto in direction opposite to gas-and-powder mixture delivery direction to seal inlet connection pipe orifices by side surface thereof. Each container is provided with inlet pipe to which aerator pipes are connected in gas-dynamic manner. Spraying nozzles provide operation of all containers simultaneously, one by one or selectively and free gas-and-powder mixture delivery under pressure overcoming fire heat depression and with rate exceeding fire heat flow rate. Spraying nozzle of each container has immovable cylindrical nozzle member, sliding nozzle member arranged coaxially with immovable one and shutoff valve. Shutoff valve is made as a cylinder with bottom closing gas-and-powder mixture delivery orifice and contacting with sealing plug arranged inside immovable nozzle member. Shutoff valve is provided with shear leaden rivets inserted in orifices formed on outer surface thereof. When rivets are brought into contact with annular seat groove bottom formed on mating part of immovable nozzle member rivets are unriveted. Sliding nozzle member and shutoff valve are connected one to another through plate rigidly secured to sliding nozzle member from one plate side and with shutoff valve from another side thereof so that plate may bend relative vertical axis together with the shutoff valve, wherein lower part of immovable nozzle member and upper part of sliding one have beads to provide mutual engagement thereof.

EFFECT: increased extinguishing capability, extended operational functionality due to provision of optimal gas-and-powder mixture delivery regime on the base of fire heat parameters; widened range of gas-and-powder mixture delivery heights, increased mixture density and uniformity of spray cone, decreased flow resistance of the spraying nozzle.

26 cl, 7 dwg