US2599796A - Means for the extinction of fire in tanks for combustible liquids - Google Patents

Description

Jun 10, 9 A. E. WICKLANDER 2,599,796

MEANS FOR THE EXTINCTION OF FIRE IN TANKS FOR COMBUSTIBLE LIQUIDS 2 SHEETS-SHEET 1 Filed March 11, 1950 INVENTOR ATTORNEY J 1952 A. E. WICKLANDER MEANS FOR THE EXTINCTION OF FIRE IN TANKS FOR COMBUSTIBLE LIQUIDS 2 SHEETSSHEET 2 Filed March 11, 1950 INVENTOR mamas f/ /A/l flfl Mmwvm ATTORNEY Patented June 10, 1952 MEANS FOR THE EXTINCTION OF FIRE IN TANKS FOR COMBUSTIBLE LIQUIDS Anders Emanuel Wicklander, Nynashamn, Sweden Application March 11, 1950, Serial No. 149,187 In Sweden October 31, 194.9

9 Claims.

The present invention refers to the extinction of fire in tanks, containers or other storage rooms for combustible liquids, particularly tanks for inflammable oils, such as gasolene and crude oils.

The principle of fire extinction in tanks according to known methods aims at the provision of an insulating blanket of a fire extinguishing agent, generally foam, between the liquid and the air, thus starving the fire by stopping or retarding the evaporation. In a known method,.

the foam is supplied through the roof of the tank or through the upper portion of the wall of the tank by means of one or more inwardly projecting pipes, which are open toward the interior of the tank, and from these pipes the foam is introduced above the surface of the liquid in order then to fiow out to cover the whole of the liquid surface, after sufficient quantities of foam have been applied, the result being then the starving 'of the fire. This method of supplying the foam is rather uneconomical, however, inasmuch as one must take into consideration that large portions of the foam will be broken down, when the foam passes directly through the flame-zone, which may have a temperature of up tol000 0., or that the foam is carried off by the wind. For this reason another method (the subsurface method) has been evolved, according to which foam is pumped in through the ordinary supply lines for the oil directly into the oil, in which the foam has been permitted to rise to the surface. This method also suffers from a considerable drawback, inasmuch as the foam on its way in the oilup to the surface is broken down to a-considerable extent, which is particularly the case with oils of a low viscosity, such as gasolene.

The primary object of the invention is to facilitate the supply of fire extinguishing agents to tanks or other storage rooms for combustible liquids in a manner more satisfactory than ac cording to the known methods. The invention is based on the observation that, when a fire occurs in tanks containing an inflammable oil next to the liquid surface underneath the flame-zone, there is a layer consisting of evaporated oil, which maintains the fire when fiowing in a constant current from the colder surface of the liquid. In this gas-zone the temperature is considerably lower than in the flame-zone thereabove. One object of the invention is to utilize this gas-zone for the supply of a fire extinguishing agent in a manner such that the supplying apparatus will not be made ineffective bythe re. I

2. l The invention comprises a method of fire-extinction as well as a suitable contrivance for such extinction. f The method is primarily distinguished by the feature that a fire extinguishing agent, such as foam or an inert gas, is introduced into the storage room (the tank) at-a point underneath the liquid surface therein: through the combustible liquid, said agent being prevented on its way through the liquid from coming into contact with the latter, until it has reachedthe surface of the liquid or has been brought into-the proximity of the same. The fire extinguishing agent may thus be introduced at a point of the Wall of the tank located at a low level, if desired through the bottom of the tank, but for the conveyance up to the surface a contrivance is made use of, which prevents the fire extinguishing-agent from coming into contact with the liquid and .from being destroyed by the latter. For the conveyance on or more closed envelopes maybeemployed, into which the fire extinguishing agent is-introduced, and the envelope is made from a material resistant to the contents of the tank, which material might be destroyed, however, through an infiuence from the heat of the fire on that portion. of

the envelope which, during-the fire, is above the liquid surface in the tank, so that the envelope is opened bythe fact that said portion is burnt off or fused, or is destroyed in some other way, so that the fire extinguishing agent is permitted to reach the surface of the liquid. The envelope may be constructed in various ways, and measures other than destroying a portion of the envelope may be resorted to forthe opening ofthe same.

An apparatus devised in accordanc with the invention is primarily distinguished by thefeature that it is provided with .a conveying means adapted to bring fire extinguishing means from a point on the wall of the storage room, which is located underneath the level of the liquid in this room, up to the surface of the liquid, in a manner such as to prevent the fire extinguishing means from coming into contact with the combustible liquid, until it has reached the level of the liquid, or has been brought to the proximity of the same.

The invention will be explained more closely in the following. with reference to the accompanying drawings, which illustrate a few examples of embodiment. Fig. 1 is a vertical section of an oil tank under fire, this figure also showing .zones caused by the fire. Figs. 2, 3, 4 and 5 are vertical tion and arranged on a tank. Fig. 6 shows a de= tail.

In Fig. 1, I designates a tank or other storage chamber or room for a combustible liquid, such as a gas oil. The upper surface of the liquid is locatedat l 2. Under fire there is a zone l4 next to the surf'ace of theeliquid, 'saidizone consistin of vapour; which in a constant current-from the colder surface of the liquid maintains the fire. Here, the temperature is considerably lower than.

in the flame-zone I6 thereabove; the smokeezoner l8 developing above said flameezone; lnlthe fi i zone M, where the temperature is comparatively low, as stated, a. suitable fire extinguishing means, such as water or foam, is introduced an cording to the invention, saidsmeanszbeinggpere 1 mitted to extend over the surface of theliquidrsor:

as to cut off the latter from the air evaporation. and insulate the surface thus starving the fire (stopping thesupply of gas) v I'fthe level of theliquid inthetank were constant and known; the fire extinguishing means could be supplied from the side-through'a duction of an envelope 26 intended to convey an extingutfihinggagent or means from a pipe conduit ram-m thewmzface of the liquid. The envelope may takethe form of a flexible hose or tube. whichjrra-position of preparedness is lying folded in a pocket 39 between the pipe conduit and the dneningahz. .Thesouter end of the hose is secured wi'tltnaitight fit to the inlet socket of the pocket,

.smthat. leakage of liquid from the tank is prevented. Provided between the pocket and the opening is acut-off vaive 3| attached to a socket 32"surroundingtheopening: V

The valve-34 is; normallyolosedi-wliereby liquid is prevented from escaping fromthe tank through device loeatedimmediately above thesurface of m the-liquid. Inpractice; the level of the liquid generally" varies' to 'agreat extent according to the degreeof filling of the-tank. In order that th'e fire extinguishing meansshall permit of beingintroduced at theproper level; without becominguestroyed by the heat from the flame-zone Orrbytheiiquid inthe: tank, it= is introduced, according-tattleinvention, at' a; point beneath the is'urfaeeioffethe" liquidrand' is caused to-pass I through :the. liquid; it beingpreventedfromcom,- V

' intoscontact'with the latter before havlngfreachedthe'surface of; the liquid. The point of: introduction is selected at a; comparatively low. level; preferably attire-side of; the tank whiciialsq-involves theadvantagethatthemeans ofiintroduction become readilyaccessible;

Tq-conveyithe extinguishing-meansfrom the pointof'irrtroductionto'the gas zone above the f surface of-the liquid, a conveying means may be m mes: which-within the; scope-of the invenj tlbnmaybefbrmedin manydifierent ways; a few of whiohiarecshowniby Way; of example in the Inprincipl'e, this: contrivance-is cOnstltutedhya shell or-a1renvelope, into: which the extinguishing-meansis introduced at the bottom tube corweyed toand deliveredonto -a pointiabove besidie'the'surface oftheliquid; Fig, 2 shows a" tank i0; which is filled with a combustibleliquid to the'level l2, the envelope; in consideration taki'ngtheiorm of a pipe or tube 20,,which' is permanently secured-within the tankin a position suited. for the supply of extinguishing means. A H nozzletor socket 22 the extinguishing means extends through the, wall of the tank tov adjoin the pipe 20. The pipex2'fl' extends a vertical direction beside the'wall of the t'ank,,to which it maybe. secured. It. is closed as the upper and the lower ends, but consists of a material, which is readiiydestroyed at a certain increase of the temperature, whereby the pipe is opened. At a. fl'regthis destruction may thus consist in that the whole oi'the portion 23 of? the pine projecting above the surface. l2 of the. liquidis burnt off; so

that" extinguishing means supplied through the socket '22" can be pumped without impediment. lira constant current up. to the surface of the Iiguidto'b'ef spread over the latter. This device may lie-used for: arbitrary extinguishing; means, consequently not only for such having a specific gravitypsmallen than that of the liquid in the tank, such as'foamsand gas, but also for water the opening -2 4 At a.-fire;;thevalve 3 l is opened,

the-hose thenpreventing any discharge-ofliquid. Fire-extinguishing agent is now supplied under pressure through the-conduit28 so as to fill the hose 26; whichis pressed into thetankwhere it unfolds. The hose is of: a'l'engthsuchthatit may'reach with its innerendifor'a distance above thesurfa-ceof theliquid; In; Fig.3, the hose ismarked -in-this position by dash lines 26. Various measures of expediencwmay be taken to bring the;hoseinto this position. Thesimplest way is" tomakeuse of afire extinguishing-agent,

the specifie'weight off which is semuch below that of the combustible liquid that. thehose is caused to rise to the surface. Particularly suitable as;;a fire extinguishingagentis, therefore; mechanically or chemically-produced foam or some inert gas. Another way isto arrange a guiding rneans within thetank; suchas:;a rigid; preferablyperforated pipe 33; through whichthehose-is directed upwardly-during its projection. Thehose nrustjae closed against the contentsoj; tanlr while floating upror rising to the suriace, in; order then to be opened, :so that;the-extinguishing agentmay find itsway-o-utto be spreadgoverthe surface of the liquid. Arr-entirely automatic opening of the hose may be achieved" in apartieularlv simple manner by thehose being made from a material, which is destroyed, for instance lay-being ignited, and which then burns or melts under; the influence ofthe heat of radiation from the flame- The hose may. consist, v for instanc of synthetic rubber, which looses its strength; at a temperature, as low. as 70, for example and'which is thus destroyed at the temperature prevailing inthegas zone tld in Fig; 1). Plastic of a low meltingpointis also serviceable. When the hose projects for some distance abovethe liquid' sura this 'pr jeetine-pnrtipn. wilithereimte be opened,;so that the extinguishing agentmay find its wayout.

The envelopecneed' not take the iorm of a hose, but mayhaveany suitable iiorm providedit is capable of conveying the I extinguishing agent through the combustible liquid upto the surface of the l W thout-the ext neuishinsagentand he liq dbein .b us tzinto mutual contact e tnoth r. formiis ndieatedby-chaim dotted lines Ml inFig; 3. 1 7 Irrespective of. whether the form of a hose. or not, it may be opened through the influence of the pressure from the extinguishntelone takes. th

ing agent therein, the envelope then consisting of a more temperature-resistive, perhaps a refractory material, such as asbestos. 'I'o render this possible, the'inner end of the envelope may be provided with breakage or weakening lines, for instance in the form of a circumferentially extending weakening line 34, as shown in Fig. 6, the end portion 36 thus bursting oif, when the pressure has reached a sufficiently high value in the envelope. a valve may be provided, which is adapted to open through the pressure in the shell. This facility is elucidated in Fig. 5, which shows the hose 26 in a projected position with its upper end above the liquid surface 12. the upper end is a valve member 36, which is kept in its closed position by a locking spring 38; the resiliency of this spring may be outweighed by the pressure in the hose, so that the valve can be opened through the influence of this pressure. If required, a float may be arranged in'a suitable position on the hose, said float aidingtoward bringing the end of the hose up to the surface of the liquid.

A special advantage of the closed pipe or hose employed according to the invention is that it forms itself a sealing means and in contradistinction to devices for introduction of foam through the tank roof improves the sealing possibilities and reduces the breathing losses.

As a conveying means for the extinguishing agent, particularly where the latter consists of foam or gas, balloons may be used in placed a pipe or a hose, said balloons being filled with an extinguishing agent and introduced into the tank in large quantities. An arrangement for this purposeisindicated diagrammatically in Fig. 4. A nozzle is secured to the socket 34 in the a film in contact with the contents of the tank is introduced through said pipe 50. This filmforming agent is pressed out into the annular opening 52 between the nozzles, and the film is' dilated by the extinguishing agent introduced through the'nozzle 48. In the example shown, the extinguishing agent is conceived of asconsisting of foam created in a foam injector 54 provided with an injector nozzle 56, a water inlet 58, and an inlet 80 for a foam-forming agent. The film is closed by means of a device arranged in front of the nozzles 46, 48, so that the. film is caused to form balloons 62, which in rapid succession rise to the liquid surface l2, where they are opened by the destruction of the film through the influence of the heat of the fire. For the production of the balloons any suitable apparatus may be used, which is capable 0.1 producing balloons in rapid succession, the ordinary means for the supply of gas as used in previously known balloon producing machines being used here for the supply of foam.

What I claim is:

1. An apparatus for extinguishing fire in tanks or other storage chambers containing an inflammable liquid comprising an inlet opening for introducing a fire extinguishing medium below the surface of said liquid, an envelope for said fire extinguishing medium adapted to be projected from said inlet opening to a point above the liquid surface, said envelope being made of material at least a portion of which is fusible but impervious In place of such breakage lines,

Arranged on 6 to said liquid, and means for projecting said envelope and said fire extinguishing medium from said inlet opening. I

2. An apparatus for extinguishing fire in tanks or other storage chambers containing an inflammable liquid comprising an inlet opening for introducing a fire extinguishing medium below the surface of said liquid, an envelope for said fire extinguishing medium adapted to be projected from said inlet opening to a point above the liquid surface, said envelope being made of material at least a portion of which is fusible but impervious to said liquid, a pocket connected to said inlet opening for normally housing said envelope, and means for projecting said envelope and said fire extinguishing medium from said pocket.

3. An apparatus for extinguishing fire in tanks or other storage chambers containing an inflammable liquid comprising an inlet opening for introducing a fire extinguishing medium below the surface of said liquid, a collapsible envelope for said fire extinguishing medium adapted to be projected from said inlet opening to a point above the liquid surface, said collapsible envelope being made of material at least a portion of which is fusible but impervious to said liquid, a pocket connected to said inlet opening for housing said envelope in collapsed condition and means for projecting said fire extinguishing medium and said envelope from said pocket.

4. Apparatus for extinction of fire in tanks or other storage chambers for combustible liquids comprising a flexible tube being closed save for an inlet and made from a material resistant to the combustible liquid but destructible by the influence of the fire, said tube having an inlet below the liquid level in the chamber, means to keep said tube in a folded state of readiness, means to develop the tube through the liquid up to and above the surface thereof, where it is closed, and means to supply extinction means to said tube.

5. Apparatus for extinction of fire in tanks or other storage chambers for combustible liquids, comprising a flexible envelope being closed save for an inlet located below the liquid level in said chamber, means to supply extinction, means to the envelope through said inlet, said extinction means having a specific gravity lower than that of the liquid in the chamber and thereby causing a portion of the envelope to rise to the surface of the liquid, the envelope being made of a material resistant to the liquid but destructible by the fire, whereby the envelope is automatically opened above the surface of the liquid due to the fire itself.

6. Apparatus for extinction of fire in tanks for combustible liquids comprising a pocket at the wall of the tank below the liquid level therein, said pocket having an inlet'and an outlet. a flexible tube folded together in said pocket, said tube having an open end at the inlet and a closed end at the outlet, and means to supply extinction means into the tube to develop the tube in the liquid of the tank causing the closed end to rise above the liquid surface.

7. Apparatus for extinction of fire in tanks for combustible liquids comprising a pocket at the wall of the tank below the liquid level therein, said pocket having an inlet and an outlet, a flexible tube folded together in said pocket, said tube having an open end at the inlet and a closed end at the outlet, and a foam jet pipe for supplying foam under pressure into the tube to develop the tube into the liquid causing the closed end :o': the-tube to .rise t9 t e suriace iof' he -.1i m

to the bueyeiieyef thefeam- 8. Apparatus for extinction ofiire i mks. for

having. an open'endat the inlet and a, closed, end at the-outlet,.mean s to supply extinction means into the tube to develop the tube in the liquid,

and means uidin the tu or ausi th tinction means but being .elosed save for this inlet, said. inlet being located below thelevel of the liquid in-the storage chamber, a pocket for said.

4 .emnelepeet he well pi thete k o .c emher, sai

pocke beineitself open te a 'd he innerxef h chamber but being closed bythe envelope.

ANDERS EMANUEL WICKLANDER- mummi s CI ED The iellowine re c are otrecorsl 11 th fil o t is pa e U D TATE A T Number Y N ame Date 1,776,206 Verner Sept. 16,:1930 1,843,882 Norling Feb. 2, 1932 "1,876,425 King Sept. .6, 1932 FOREI PAT NTS .1n,1 -v C unt Dat 700,499 Fra Dee-23.

Claims (1)

1. AN APPARATUS FOR EXTINGUISHING FIRE IN TANKS OR OTHER STORAGE CHAMBERS CONTAINING AN INFLAMMABLE LIQUID COMPRISNG AN INLET OPENING FOR INTRODUCING A FIRE EXTINGUISHING MEDIUM BELOW THE SURFACE OF SAID LIQUID, AN ENVELOPE FOR SAID FIRE EXTINGUISHING MEDIUM ADAPTED TO BE PROJECTED FROM SAID INLET OPENING TO A POINT ABOVE THE LIQUID SURFACE, SAID ENVELOPE BEING MADE OF MATERIAL AT LEAST A PORTION OF WHICH IS FUSIBLE BUT IMPERVIOUS TO SAID LIQUID, AND MEANS FOR PROJECTING SAID ENVELOPE AND SAID FIRE EXTINGUISHING MEDIUM FROM SAID INLET OPENING.

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