US2452348A

US2452348A - Fire extinguishing method

Info

Publication number: US2452348A
Application number: US601234A
Authority: US
Inventors: Walter A Beach
Original assignee: Cardox Corp
Current assignee: Cardox Corp
Priority date: 1945-06-23
Filing date: 1945-06-23
Publication date: 1948-10-26
Anticipated expiration: 1965-10-26

Description

Oct. 26, 1948.

Filed June 25, 1945 a"? H i i w. A. BEACH 2,452, 348

FIRE EXTINGUISHING METHOD 2 Sheets-Sheet l INVENTOR.

- ilbzlierABeacb Oct. 26, 1948 I Y w A. BEACH FIRE EXTINGiIISl-IING METHOD Filed June 25, 1945 2 Sheet-Sheet 2 I we 44 [limb HUM: Itifltj V IN V EN TOR.

Patented Oct. 26, 1948 S EARCti 2,452,348 FIRE EXTINGUISHIN G METHOD Walter A. Beach, Chicago, Ill.,,assignor to Cardox Corporation, Chicago, Ill., a corporation of Illinois Application June 23, 1945, Serial No. 601,234

3 Claims.

This invention relates to methods for extinguishing fires in enclosures in which flammable substances are employed in performing certain process or treatment steps.

It is the present practice in numerous industries to perform certainprocess or treatment steps, involvin the use of highly flammable substances, such as liquids, gases, powders, or the like, in relatively small booths or enclosed spaces whichare entirely, or almost entirely, open at one side or wall. Consequently, fires occur in such enclosures relatively frequently due to the quantity of wasted treatment substance that accumulates on the floor. This accumulated material usually is sufllcient to produce a flre that involves the entire interior of the enclosed space. The construction of these enclosures with a sizable permanent opening, the readily displaceable charactor of the flammable substances employed, and the size of the conflagration present a diflicult extinguishing problem.

It is a primary object of this invention to provide methods of extinguishing fires involving highly flammable substances that are burning in enclosed spaces, such as spray booths, which are provided with relatively large, permanent side wall openings.

A further important object of the invention is the provision of methods for employing carbon dioxide, or other similar extinguishing medium, to eifect the extinguishment of fires involving processingor treatment booths or enclosures, having large permanent side wall openings, without endangering surrounding property as a result of scattering burning treatment substances or causing flash-out of flame through the openings.

Other objects and advantages of the invention will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like numerals are employed to designate like parts throughout the same,

Figure 1 is a perspective view of two adjacent processing or treatment booths, or enclosures, with the fire extinguishing apparatus embodying this invention properly associated therewith,

Figure 2 is a vertical sectional View taken through one of the booths, or enclosures, of Fig. l and on line 2-2 thereof.

Figure 3 is a vertical sectional view taken on line 33 of Fig. 1,

Figure 4 is a schematic view looking down on one of the processing booths and illustrates the swirling motion of the extinguishing medium that cause the medium to swirl through a differentpath within the enclosure.

In the drawings, wherein for the purpose of illustration are shown the preferred embodiments of this invention, and first particularly referring to Fig. 1, the reference characters A and B designate two enclosures or booths in which Processing or treatment steps are intended to be performed with the aid of suitable, flammable substances, which may take the form of liquids, gases, or powders. These booths or enclosures are formed by the three side walls C, D and E, the rear walls F and G, the top walls H and I, and the bottom walls L and M.

During the use of these enclosures or booths A and B for performing process or treatment steps on different articles, objects, or parts,-the highly flammable treatment substance, particularly when it is sprayed or blown on the objects being treated, will accumulate on the floors L and M of the enclosures. This accumulated material, therefore, will constitute the source of supply of fuel that feeds a fire after ignition has occurred in a booth. If the treatment substance is a liquid, the fuel will be formed by the mixing of vapors rising from the flammable liquid and the air within the enclosure.

To effect extinguishment of a fire within such an enclosure, or booth, it is necessary to accomplish one or more of the following:

1. Create a fire extinguishing atmosphere within the enclosed space. This is rendered diflicult bythe fact that the enclosures are entirely open at their front walls.

2. Cool and highly flammable substance that is feeding the fire, and all associated heat absorbing objects and materials, below the ignition temperature Of the flammable substance.

3. Cut off from the fire zone the vapors that are rising from the highly flammable substance and mixing with air to form the combustible mixture.

4. Accomplish the above without blowing the highly flammable substance out of the booth, or enclosure, and without causing flash-out of the flame through the open side wall of the booth.

The fire extinguishing medium that is preopen sides of the enclosures.

ferred for practicing this invention is carbon dioxide. It will be appreciated, however, that other inert, or fire extinguishing, liquefiable gases may be employed, such as nitrogen, methyl bromide, etc. The extinguishing medium is illustrated in Fig. 1 as being conducted to the two enclosures A and B by the main supply line I and the two branch lines 8 and 9. Manually operable or automatically actuated control valves I and II are located in the branch lines 8 and 9, respectively, to provide means for starting and stopping the fiow of the extinguishing medium to the discharge nozzles l2 and I3 that are connected to the respective ends of the branch lines 8 and 9 that are located within the enclosures or booths A and B.

To create a fire extinguishing atmosphere within the enclosures A and B, it is necessary to discharge into these enclosures the fire extinguishing medium at a sufficiently rapid rate to take care of the loss of the medium through the Additionally, the extinguishing medium should be discharged into the enclosures in such a way that it will sweep across the bottom walls, or floors, of the enclosures to cut off and dilute the fuel forming vapors that rise from the highly flammable substance accumulated on the enclosure fioors. These two desired results could be accomplished very easily if it were not for the fact that the fire extinguishing medium, also, must be discharged in such a way that its.velocity will be dissipated or reduced to a substantial extent before the medium sweeps the floor of an enclosure. Otherwise, the highly flammable substance will be blown through the open side of the enclosure and the fire will be spread to adjacent areas outside the involved hazard. Additionally, the fire extinguishing medium should be discharged in such a manner that it will build up or accumulate within the enclosure and will not cause the flame to flash-out through the open side of the enclosure.

It has been determined that all of the above desired results best can be accomplished by so locating the nozzles I2 and I3 that they will occupy positions approximately two-thirds of the way back from the open fronts of the enclosures and relatively close to one side wall. In addition, the nozzles should point downwardly, or toward the adjacent side walls, at an angle of approximately 45 and should point backwardly, or toward the back walls, at an angle of approximately 15. This preferred location and angular arrangement is illustrated in Figs. 2 and 3.

By considering Figs. 4 and 5, it will be seen that this location and arrangement of the discharge nozzle !2 causes the discharged extinguishing medium to impinge against and be deflected by the adjacent side wall C and then to impinge against and be deflected by the rear wall F. These two deflections of the discharged stream of fire extinguishing medium cause the latter to partake of a swirling motion within the enclosure and to sweep across the floor, to dilute and cut off rising vapors, after being deflected by the rear wall F. Consequently, the velocity of the discharged medium, by the time it reaches the floor, is reduced to such an extent that it will not blow the highly flammable substance through the open side of the enclosure. The location of the discharge two-thirds of the way back from the open front of the enclosure causes the extinguishing medium to build up at the back of the enclosure first and to work toward the open front as a solid cloud or bank of extinguishing atmosphere.

Again referring to Fig. 1, it is pointed out that if the booth, or enclosure, is large enough to be represented by the two booths A and B, when thrown together by the removal of the intermediate side wall D, both of the discharge nozzles I2 and [3 should be employed to effect extinguishment in this large enclosure. With the intermediate side wall D removed, and with both nozzles discharging the fire extinguishing medium, the two discharges will meet and blend together at the intermediate zone of the enclosure. Consequently, a solid fire extinguishing cloud or bank will be formed throughout the entire vertical section of the enclosure, at the rear portion thereof, and will advance toward the open front in the same manner as has been described above in connection with the enclosure A.

Referring now to Fig. 6, it will be seen that the fire extinguishing medium supply line H is so arranged that the discharge nozzle I5 is located about two-thirds of the way back from the open front of the enclosure and is so positioned that the discharged stream will first impinge against the top wall H at approximately the transverse center line thereof. The discharged stream then will be deflected toward and will impinge against the side wall C of the enclosure. After this impingement, the extinguishing medium will be caused to sweep across the floor L as a result of the swirling motion imparted to the extinguishing medium.

This embodiment of the invention will not take care of as wide an enclosure or booth as the nozzle arrangement illustrated in Figs. 1 to 5 inclusive because the velocity of the discharged medium is reduced to a greater extent by the time the medium sweeps the floor of the enclosure and passes over to the vicinity of the side wall D. That is to say, if the enclosure is too wide, there is a detectable delay in extinguishing the fire at the side of the enclosure that lies adjacent the Wall D.

A suitable nozzle for discharging the fire extinguishing medium into the enclosures is illustrated in the patent of Harry Ensminger, No. 2,289,352, issued July 14, 1942.

It is to be understood that I do not desire to be limited to the exact order of method steps as they have been disclosed, for variations and modifications of the same, which fall within the scope of the accompanying claims, are contemplated. It further is to be understood that the particular type of apparatus herein shown and described is to be taken as a preferred example of the invention, and that various changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described the invention, I claim:

1. A method of extinguishing a fire involving a highly flammable, readily displaceable substance that is burning on the floor of an enclosure that is open at its front, comprising releasing liquid carbon dioxide into the enclosure to produce a mixture of snow and vapor, and so directing the mixture that it will impinge against and be deflected by two angularly arranged walls of the enclosure to reduce the velocity of the discharge before the extinguishing medium reaches the floor and to cause the medium to sweep across the floor in a direction substantially paralleling strata amt:

the open front for cutting off flammable vapor rising from the floor to feed the fire.

2. A method of extinguishing a fire involving a highly flammable, readily displaceable substance that is burning in an enclosure that is open at its front, comprising releasing carbon dioxide into the enclosure to cause its sudden expansion to convert it to a snow and vapor mixture, and directing the said mixture at such an angle with respect to a rear corner of the enclosure that the mixture will impinge against the two angularly arranged walls forming said rear corner in a general downward direction and inwardly away from the enclosure opening to reduce its velocity and to cause the resultant extinguishing atmosphere to build up at the rear of the enclosure and to move toward the front opening as a dense cloud or bank.

3. A method of extinguishing a fire involving a highly flammable, readily displaceable substance that is burning on the fioor of an enclosure that is open at its front, comprising releasing liquid carbon dioxide into the enclosure to pro-.

duce a mixture of snow and vapor, and directing the mixture at such an angle with respect to the top wall of the enclosure that the stream will impinge successively against said top wall and a. side wall to reduce its velocity and to give the medium a swirling motion within the enclosure 6 which will carry it across the floor in a direction substantially paralleling the open front for cutting off flammable vapor rising from the floor to feed the fire.

WALTER A. BEACH.

REFERENCES CITED The following references are of record in the file of this patent: 10

UNITED STATES PATENTS Number Name Date 301,744 Monch July 8, 1884 726,200 Stover Apr. 21, 1903 1,760,359 Hiss May 27, 1930 1,831,193 Quitschalle Nov. 10, 1931 2,050,687 Allen Aug. 11, 1936 2,084,719 Allen June 22, 1937 2,090,279 Allen Aug. 17, 1937 2,097,908 Allen Nov. 2, 1937 2,125,057 Wood July 26, 1938 2,202,176 Timpson May 28, 1940 2,283,775 Thompson May 19, 1942 2,322,758 Williamson et a1. June 29, 1943 FOREIGN PATENTS Number Country Date 1,084 Great Britain Jan. 13, 1912