Classifications

• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62C—FIRE-FIGHTING
  • A62C5/00—Making of fire-extinguishing materials immediately before use
  • A62C5/02—Making of fire-extinguishing materials immediately before use of foam
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62C—FIRE-FIGHTING
  • A62C31/00—Delivery of fire-extinguishing material
  • A62C31/02—Nozzles specially adapted for fire-extinguishing
  • A62C31/12—Nozzles specially adapted for fire-extinguishing for delivering foam or atomised foam
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B3/00—Spraying or sprinkling apparatus with moving outlet elements or moving deflecting elements
  • B05B3/02—Spraying or sprinkling apparatus with moving outlet elements or moving deflecting elements with rotating elements
  • B05B3/04—Spraying or sprinkling apparatus with moving outlet elements or moving deflecting elements with rotating elements driven by the liquid or other fluent material discharged, e.g. the liquid actuating a motor before passing to the outlet
  • B05B3/06—Spraying or sprinkling apparatus with moving outlet elements or moving deflecting elements with rotating elements driven by the liquid or other fluent material discharged, e.g. the liquid actuating a motor before passing to the outlet by jet reaction, i.e. creating a spinning torque due to a tangential component of the jet
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B7/00—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas
  • B05B7/0018—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas with devices for making foam
  • B05B7/005—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas with devices for making foam wherein ambient air is aspirated by a liquid flow

Definitions

• the present invention regards a method for manufacture of a fire retarding foam, whereby water, gas (e.g. air) and foam fluid is mixed and foamed, a nozzle head, comprising a nozzle head insert, which is arranged in such a manner so as to be rotatable under the influence of water pressure, relative to an inlet piece, and at least one outlet pipe, which is a foam pipe and which is in fluid communication with the inlet piece via the nozzle head insert, where the foam pipe, at the end which faces the nozzle head insert, is provided with at least one suction port for intake of air to the foam pipe, in order to produce a fire retarding foam and an arrangement at a fire extinguishing installation, comprising a nozzle head insert, which is arranged in such a manner so as to be rotatable under the influence of water pressure, relative to an inlet piece, on which nozzle head insert is provided at least one nozzle, which is in fluid communication with the inlet piece via the nozzle head insert.
• a nozzle head insert which
• a nozzle head as mentioned above is essentially known from SE 362,793, in which is shown a foam pipe that has inlet ports at the rear, for drawing in air through a venturi effect. The air mixes with the fluid, and is ejected as a foam.
• Norwegian patent no. 124,575 discloses a fire extinguisher with several nozzles provided on a nozzle head, and in which combustion gas is sucked into a cavity in a shell and then led out of this together with the extinguishing water.
• the combustion gases are sucked in through an opening in which is arranged vanes in order to further improve the suction capacity, and into a cup-shaped compartment.
• the water nozzles extend through this compartment.
• the orifices in the water nozzles end immediately in front of openings formed in the cup-shaped compartment. When water pressure is applied, this will act to create underpressure in the cup-shaped compartment, which will draw the smoke out of this. There is no description of any foam being formed by this fire extinguishing device.
• NO 176,748 discloses a spray nozzle for fire extinguishing. Due to the inclined arrangement of the nozzle channels relative to the circumference of the nozzle head, the nozzle will rotate when water pressure is applied. During fire-fighting, the water will be atomised, but no formation of foam has been described.
• NO 179,735 also discloses a nozzle for fire extinguishing, where a whirling device is arranged in each nozzle, which whirling device rotates under water pressure in order to hurl the water out with a strong turbulence, thereby achieving a water fog. Foam formation is not described here either.
• US 5,284,298 shows a rotatable nozzle head for hosing, which is intended for cleaning purposes, and not fire extinguishing. Between the supply pipe and the nozzle pipe is shown a gap that at first seems to be arranged for air intake, however the role of this is to accommodate movements due to expansion of the material, and it should be as small as is practical. Orifices outside of this gap are there to release accumulated fluid and leaks. It is not intended that air be drawn in through these orifices and the gap.
• NO 177,455 shows a rotating nozzle head comprising four nozzles arranged at right angles to each other, wherein the nozzle head rotates due to the reaction force of the water.
• a fan is mounted on the axle of the nozzle head, which fan draws air down towards the nozzles.
• a foam net is provided outside of the nozzles. When the air-liquid mixture hits the foam net, foam is formed.
• US 3,428,131 discloses a device that is very similar to the device in NO 177,455. This also includes a rotating nozzle head, a fan and a foam net. The most significant difference is the direction of foam ejection.
• Foaming additives were at one time introduced for the purpose of creating a barrier between the burning material and the surrounding air, i.e. to keep out the oxygen, which is one of the three elements that are required to sustain a fire.
• the foaming agents formerly called foam fluid, were at first made from boiled slaughterhouse waste, which gave off a terrible smell. These days, these agents are largely produced synthetically. 25-30 years ago, the so-called AFFF (A-trippel-F) fluids appeared, "Aquous Film Forming Foam", and these are still considered to be the best in the market.
• the foam from these fluids form a film or membrane that covers the burning material after the foam itself has dried up, so as to protect against ingress of oxygen and prevent a fresh outbreak of the fire for hours and days after the fire has been put out.
• the AFFF liquids are now tailored to several types of fires.
• the well known Universal ® Gold 3% AR-AFFF made especially for fighting fires involving hydrocarbons and alcohols.
• this is a liquid that is mixed in a 3% ratio with water.
• Concentrates that are mixed in 6% and 1% ratios with water also exist, however 3% is the most common.
• a foam mixing unit is used to add the foam concentrate to water that is on its way to the nozzle, thus forming the foam.
• This mixer is normally of the ejector type, which sucks up the foam concentrate and mixes it with water after having been pre-set to the correct mixing ratio. The mixture is mixed with air in the nozzle itself.
• the object of the present invention is to provide a method and fire fighting means that, in all parts of a room showing signs of fire, efficiently distribute fire fighting foam automatically, quickly and evenly.
• this is achieved by adding the gas (e.g. air) to the water under pressure before the gas/water mixture leaves a nozzle for spreading of the foam.
• the gas e.g. air
• a nozzle head is further achieved according to the invention, by the suction port at least partially being surrounded by a hood that forms a compartment or pressure chamber in front of the suction port, the compartment or pressure chamber having an open side that faces the direction of rotation of the nozzle head insert, whereby air is forced into the compartment or pressure chamber during the rotation of the nozzle head insert.
• An arrangement at a fire extinguishing installation is also achieved according to the invention, by it also comprising a gas source connected to a water source for introducing gas into the water under pressure.
• the gas is preferably an inert gas and causes a significant increase in the foam volume.
• the rotation of the nozzle is provided by at least one, preferably several foam pipes being attached to a rotatably supported nozzle head insert. These foam pipes are placed at a defined radial distance from and at an angle to the linear axis of the nozzle head insert, and thus the water pressure will cause the nozzle head to rotate.
• the foam is formed by air being pulled into the water/foam fluid mixture in the foam pipe.
• the air stream thus enhanced effects a significant increase in the intensity of the foam production, leading to a considerable improvement in the performance of the nozzle head.
• a relatively light foam with a long degradation time is produced, decreasing the risk of post-ignition and giving less water damage.
• the nozzle head is provided with a bell-like blade casing, which defines a pressure chamber between the nozzle head insert and the blade casing.
• the air suction ports going to the foam pipes are in communication with this pressure chamber, and the blade casing is, at its suction port arranged about the circumference of the nozzle head insert, provided with a plurality of blades facing the direction of rotation.
• Figure 1 shows a nozzle head insert
• Figure 2 schematically shows a complete nozzle head according to a preferred embodiment of the invention
• Figures 3 and 4 show a side view and a plan view respectively of an alternative embodiment of the invention
• Figure 5 shows a further alternative embodiment of the present invention.
• Figure 1 shows a nozzle head insert 1 comprising a nozzle casing 2, a bearing house 3 and an inlet piece 4.
• Ball bearings 5 (alternatively sleeve bearings) are provided between the bearing house 3 and the inlet piece 4, so as to enable the nozzle head insert 1 to rotate in relation to the inlet piece 4.
• a check nut 6 keeps the nozzle head insert 1 in position on the inlet piece 4, in addition to which a gasket 7 has been provided in order to prevent water from penetrating to the bearings 5.
• FIG. 2 shows a complete nozzle head 10.
• the nozzle head insert 1 is indicated in broken lines.
• a predominantly bell-shaped blade housing 11, with an opening 12 running around the nozzle head insert 1, is screwed onto the outside of the nozzle head insert 1 by means of screw thread 17 or attached by other appropriate means.
• a compartment or pressure chamber 14 is defined between the blade housing 12 and the nozzle head insert 1.
• a plurality of foam pipes 15 extend through openings (not shown) in the blade housing 12 and are screwed into a threaded opening (not shown) in the nozzle head insert 1, which is in communication with a chamber 8 (see Figure 1) in the nozzle head insert.
• the foam pipes are provided with a plurality of suction ports 16 at their inner ends, which face the nozzle head insert, which ports are in communication with the pressure chamber 14.
• the foam pipes 15 are inclined with respect to the central axis of the nozzle head insert 1, and face the opposite peripheral direction from the blades 13.
• This foam will, due to its long degradation time, have a significantly better smothering effect on the fire than e.g. a water fog, which will only act for a few seconds.
• the foam will in an efficient manner prevent the fire from flaring up again after having been put out.
• the water consumption is also reduced considerably, thereby also reducing or even eliminating water damage.
• Figures 3 and 4 show an alternative embodiment of the invention.
• Figure 3 shows a side view of the nozzle head 10
• figure 4 shows a plan view of the nozzle head 10, with the nozzle head insert 1 only indicated in broken lines.
• each of the foam pipes 15 are provided with a hood 21 immediately in front of the suction ports 16.
• the hood 21 is conical, and fits tightly around the foam pipe 15, while the opposite end, with the greater diameter, is open.
• an open compartment or pressure chamber 14 is formed inside the hood 21.
• the open end of this compartment 14 faces the direction of rotation of the nozzle head 10.
• the hoods 21 will "collect” air, so as to form an air cushion in the compartment 14 within the hood 21.
• the pressure inside the compartment or pressure chamber 14 will be slightly higher than outside.
• the elevated pressure around the suction ports 16 allows more air to be sucked in through the suction ports 16. This increases the efficiency of the foam formation.
• the nozzle head according to the present invention can easily be mounted in an existing fire extinguishing installation, such as a sprinkler system, as the pipe piece 4 can be screwed in to replace an existing nozzle.
• the nozzle head may also be mounted on e.g. a fire hose for domestic use, and may thereby also be used with hand-held equipment.
• Figure 5 shows a nozzle 22 that is connected to a foam mixer 23, e.g. of the venturi type.
• the foam mixer 23 is further connected to a foam fluid receptacle (AFFF) 24 and, via tubing, to a water tank 25.
• AFFF foam fluid receptacle
• the water tank 25 is connected to a gas cylinder 27 through a shut-off valve 26, which cylinder contains gas, for instance pressurised nitrogen or CO 2 .
• a smoke detector 28 and a flame detector 29 are connected to the shut-off valve through a control unit 30.
• This embodiment of the present invention operates as follows:
• the smoke detector 28 and/or the flame detector 29 registers signs of fire. This results in a signal passing from these to a control unit 30 that opens the valve 26.
• a control unit 30 opens the valve 26.
• gas flows from the gas cylinder 27 into the water tank 25.
• the pressure from the gas causes water and gas to flow out through the tubing 31 to the foam mixer 23.
• foam fluid is drawn out of the foam fluid receptacle 24, among other things because of the venturi effect.
• the mixture flows out through the nozzle 22 and quickly expands to a foam.
• the nozzle 22 is arranged rotatably on a nozzle head in an appropriate manner.
• the water in the water tank 25 may be pre-mixed with gas, in order to increase the gas content of the water. If the water is not mixed with gas in advance, gas from the gas cylinder 27 will rapidly flow into the water tank in such a manner as to quickly mix with the water, for instance by leading the gas in through the bottom of the water tank 25.
• a fire extinguishing installation may be installed in places where there is no access to water from the mains.
• this embodiment may also be applied to situations where water from a waterworks is used, in which case the water mixes with the gas before the mixture is lead to the nozzle 22.
• This may, as an example, be implemented by filling water in two or more water tanks, into which the gas is subsequently led. When one tank is empty, this will be refilled.
• the nozzle Due to the high spraying capability and throw of the nozzle, which may get up to 5 to 10 metres, it is not necessary to mount this in the ceiling; it may equally well be mounted on a wall. Neither is it required that the nozzle be installed centrally in the room, as two nozzle heads located in separate corners effectively will cover the room. The nozzle heads may therefore be installed in a manner that does not cause inconvenience.

Landscapes

• Health & Medical Sciences (AREA)
• Public Health (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Fire-Extinguishing By Fire Departments, And Fire-Extinguishing Equipment And Control Thereof (AREA)
• Casting Or Compression Moulding Of Plastics Or The Like (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=19902312

Family Applications (1)

Country Status (3)

Cited By (12)

Citations (7)

• 1998
  • 1998-08-12 NO NO983690A patent/NO983690L/no not_active Application Discontinuation
• 1999
  • 1999-08-12 AU AU53105/99A patent/AU5310599A/en not_active Abandoned
  • 1999-08-12 WO PCT/NO1999/000253 patent/WO2000012177A1/en active Application Filing

Patent Citations (7)

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