US1824397A - Underwater torch and method therefor - Google Patents

Description

E. ELLSBERG UNDERWATER TORCH AND METHOD THEREFOR Filed Dec. 20, 1927 lNvENToR fda/ard' f/lsberg.

BY Kaw/@ATTORNEY Patented Sept. 22, 1931 UNITED STATES EDWARD. ELLSBERG, OF WESTFIELD, NEW JERSEY UNDERWATER TORCH AND METHOD THEREFOR Application led December 20, 1927. Serial No. 241,387.

- My present invention relates more particularly to blow torches for cutting and for autogenous welding of metal, It involves discoveries whereby it is made commercially 6 practical to cut metal under walter and particularly toperform such operation in a.

reliable manner on a commercial basis at great depths. As is well known, metal cutting torches l utilize a mixture of fuel gas and pure oxygen discharged in a composite jet llame adapted to locally heat the metal to a high temperature, whereupon a. jet of pure oxygen is blown through the llame onto the hot spot to melt or burn away the metal, the operation being carried on progressively along the line of the desired cut. In the present state of the art, acetylene and otheI` of the higher hydrocarbon gases or mix- 9 tures thereof with hydrogen, are used as the fuel constituent of the jet, because of their great fuel value per unit volume.

It has long been proposed and often attempted to perform similar metal cutting operations under water, as in submarine construction and ship salvage work, by surrounding the blow pipe flame with a sheath of air for the purpose of isolating the llame and excluding the water from the 5 surface of the metal on which the llame is directed. In connection with my work in the United States Navy, I have investigated and tested all of the most -romising of the suggested ways of doing t is, with the result that all of them have proved unreliable and frequently dangerous under relatively small depth pressures, say, 15 to 30 feet and all of them have proved entirely inoperative for the greater depths at which divers frequently do their ship salvage work. My invention involves discovery and solution of all of the difficulties which have heretofore beset such under-water metal cutting operations.

In torches of this kind, submarine or otherwise, the ratio of fuel gas to oxygen and its proper mixture must be carefully regulated in order to effect the required preheatng of the metal and the cutting thereof by the supplemental oxygenjet.

Heretofore it has been found extremely difficult and in practice impossible, to satisfactorily effect such adjustments under waterv for various reasons. It isy dillicult enough even in above-water Work. The low visibility under water makes it dillicult to see the apparatus and the work, and it is still more difficult to judge the flame conditions within the bubbling air envelope. Furthermore, the combustion conditions of 6o the jet are very different from those` in the atmosphere; Where the pressure is practically constant, it is 15 pounds per square inch. Under Water, however, even one foot increase or decrease of depth causes a change c5 of approximately 1/2 pound in the pressure the Water exerts upon the flame supply jets. Thus, at a depth of only 30 feet, the pressure is increased to l5 pounds per square inch above atmosphere, while at a workable depth of 180 feet, it is 90 pounds per square inch above atmosphere. These multiplied pressures correspondingly multiply the density of the gases in the flame within the bubble and also the back pressure on the jets which 'J5 supply the bubble. Consequently, the speeds of the gases emerging from the torch are proportionally reduced while the speed of propagation of the flame is proportionally increased. For both of these reasons, so the liability of the torch t0 back lire increases rapidly with increase of depth. As

a result it has been found impractical for a diver to properly adjust his mixture under practical conditions of under-Water work'. 235 Consequently, gas pressures for the torch have generally been controlled from abovewater in accordance with carefully prepared charts or tables of depth pressures, for the fuel gas, for the oxygen, and for the air $0 sheath, the basic pressure for proper operation at the shallowest depth, being determined by` a very careful test under laboratory conditions. While this is the best that can be done in accordance with the prior art, it proves `entirely unsatisfactory under vthe conditions of practical use by a diver where it is seldom possible to determine the precise depth of the torch, either initially, or as the work progresses. Moreover, such Work under the same conditions and withv the same maximum heating effect. For this purpose, I employ a gauge and a test bar of metal that can be held at an exactly predetermined distance from the tip of the torch, in fixed relation thereto so that the diver can closely inspect his jet and the effects of his jet on the metal. This makes it practical to supply the submarine torch with adjusting valves to be manipulated by the diver until the desired effect is produced on the test bar. In this Work, an adjustable gauge for the test bar is mounted on the tip of the torch so that when the desired adjustment is attained, it is only necessary to displace the test barand place the gauge of the torchl in direct contact with the hull of the ship or other metal to be cut, whereupon precisely the same perfect heating effect will be had on the work that was had on l the test bar.

An im ortant development is that thi method o testing and adjusting with laboratory exactness under most trying underwater conditions, soon teaches the diver precisely what positions he should set his various valves, after he has once got started on any particular job, other adjustments for substantially changed conditions being effected by resort to the test bar or to another novel method which I have discovered. The latter discoveryis that the relation between the gases used, can be easily ascertained at any depth by opening valves one at a time and adjusting each to get the proper length of bubble of each gas. For a proper mixture, the ratio of these lengths is Vconstant at each depth. Preferably, all

valves are marked so that the operator can note their individual ad'ustments and can reset them to the require opening when all gases are turned on together.

' None of the pro osed under-water torches of the prior art isclose what I have discovered to be the desirable relation for discharge of the primary fuel gas and oxgyen mixture with reference to the jet for the cutting oxygen. The same thing is true of the air sheath, with reference to the fuel and oxygen jets. I prefer to have the primary gas-oxygen mixture discharged through a circularly arranged set of parailei, relatively small jets and the cutting oxygen being discharged through a central parallel jet. The air sheath jet is a thin annulus surrounding and discharging substantially parallel with the jets of the fuel-oxygen mixture and the cutting oxygen jet. lVith such parallel arrangement of all the gas streams, turbulence is avoided and the air sheath surrounding the fiame simulates and reproduces With satisfactory 4approximation the combustion supporting relation of atmospheric air to the Haine, in the operation of an above-water torch of similar construction.

Another feature' involves discovery that there are fundamental but more or less obscure difficulties attendant upon use of acetylene and other higher carbon fuel gases, or mixtures, which have been supposed to be essential for under-water work, because their high caloriiic values were considered necessary for properly preheating submerged metal. Acetylene gas, for instance, is unstable when used under pressures and may be very dangerous when employed in a torch at any considerable depth. When subjected to depth pressures near and above 15 pounds above atmosphere, it is likely to detonate or decompose explosively, a danger entirely different from and less understood than the ordinary blow back explosions to which ordinary oxygen blow pipe mixtures are liable. Other of the high carbon gases and mixtures are subject to the same and other practical difiiculties resulting from the pressures under which they must be supplied to the jet. Freezing up is a common difficulty attendant upon the use of these gases. While various features of my invention are applicable to the use of such fuel gases, particularly at small depth, an im ortant discovery is that substantially pure ydrogen, though it has far less fuel value, is of all others, the one that can be safely used at the greatest depths. Moreover, when properly used in accordance with my invention, its fuel value and heating effect are entirely suiiicient for underwater work. These discoveries reverse the teaching of the present-day art.

The above and other features of my invention will be more evident from the following description in connection with the accompanying drawings, in which Fi l is a side elevation of a torch and attac ments in accordance with my present invention;

Fig. 2 is a view partly in section, showing the various supply pipes and air sheath nozzle in axial section in the plane of the paper, the burner tip being shown in elevationg Fig. 3 is a section on line 3 3, Fig. 2;

Fig. 4 is a vertical ction through the burner tip in the same plane as Fig. 2;

Fig. 5 1s a detail view of the test bar and attachment for the torch; and

Fig. 6 is an elevation of the gauge viewed at right angles to the direction shown 1n n these drawings, some of the structural features of the torch may be substantially the same as found in certain makes of abovewater torches but never in under-Water ltorches so far as I am aware. As concerns the burner tip and certain other features n 6 su plied from oxygen hose 7; and pipe 9 for t e cutting loxygen which is also derived from hose 7 but separately controlled by means of valve trigger 10. As will be evident from Figs. 2, 3 and 4, the hydrogen ipe 2 discharges into annular cavity 11, in iiead 12 and thence through radial holes 13 to the parallel fuel-oxygen nozzles 14, 14. The oxygen from pipe 5 passes into the annular space 15, which is cut oil' from 11 by contact of collar 16 with the contracted walls within the head 12, and from said, annular space 15 the oxygen flows through radial holes 17, into each of the same jet forming passages 14, 14, that are sup lied through the hydrogen inlets 13, there eing an oxygen inlet 17 and a hydrogenY inlet 13 for each of said passages 14.

The cutting oxygen from pipe 9 is dis-I charged into cavity 18 in the base of lsaid head 12, and Hows thence through the axial passage 19, around whichthe oxyhydrogen jets 14 are circularly arranged.

The improved attachment for affording lmy novel air sheath in combination with the flame jets 14, 14 and cutting jet 19, includes an exterior jacket or nozzle which may comprise a screw-threaded base portion 20, adapted for clamping engagement with the annulus 21 of the above described oxyhydrogen nozzle. This air sheath nozzle includes a cylindrical jacket portion 22, surrounding and of substantially greater diameter than said. jet nozzle, to afford an annular interspace 23 of substantial cross-section, permittlng relatively slow non-turbulent flow of the air up to a point 24 near the 'tip of the nozzle. Here the cross-section of this annular air-passage is greatly reduced, as shown. In this reduced portion, theinner wall 25 of the air sheath nozzle is approximately cylindrical and the tip of the nozzle at 26 is near'enough cylindrical so that the air sheath jet is discharged approximately parallel with the jets from passa es 14, 14,

which latter are to be rotected an supplied with air by said air s eath jet. The air is supplied to annular space 23 through a pipe 27, secured at one end by a gastight union 28, to a nipple 29 screw-threaded in collar 20 as shown, and at the other end b a union 30 secured to a valve 3l supplie through pipe 32 and hose 33. The air sheath supply pipe 27 and its connections 31, 32, 33 are held in fixed relation to the handle 1 of the torch by collars 34, 35 detachably secured about said handle. The jacket thus constructed distributes compressed air or other similar gas in a uniform stream around the tip of the torch in a direction parallel with the flame and oxygen jets and at a sufficient pressure entirely to displace the liquid from ltheI vicinity of the torch tip, and to form a proper cavity of air, free of liquid in which ignition and combustion of the gases to be burned can take place. The chamberk diameter is reduced near the end of the tip, so that the air is forced to escape as a film completely surrounding the tip. The length of the jacket is required to be from about 1A inch longer than the tip to l@ inch shorter; a jacket materially longer than this will prevent proper preheating of the metal b cooling 1t and one materially shorter wil allow the film air to escape without properly protecting the flame from the liquid. A long jacket will also cause the compressed air to mmgle with and dilute the pure oxygen 'discharged through the cutting hole in the tip and make cutting impossible. The valve rovided on or in the vicinity of the torch andle so that the operator may adjust the pressure of the air supplied to the jacket so as always to maintain a film of air around the tip properly to protect the flame, regardless of the depth of liquid, friction in hoses, and variations in pressure ofv the air supply at the surface, provided only that an excess pressure of air be maintained on annular space 23.

- My novel gauge as shown in Figs. 1 and 6 includesfingers 36 extending parallel with the axis of the burner nozzle, having end gauge surfaces 37, in a plane at right angles to said' axis. The auge fingers are made adjustable axially o? the jet, preferably by making them integral with a screw nut 38 engaging threads 39 on exterior of the air sheath nozzle. VSuch an adjustable gauge or spacer is ractically essential in under-water work to .'eep the tip of the torch at the adjusted to suit the condition at the depth at which cutting is to be done.

j While this gauge construction and mounting is new and useful for a'diver highly experienced in the use of my apparatus in accordance with the above described methods, I prefer to provide, even for the experienced diver, a means for supporting a metal test bar 4() in fixed contact with the gauge surfaces 37 of gauge fingers 36. Aconvenient and simple form of clamp comprises members 41, 42 formed at their outer ends with opposite edge clamps 43, 44 engaging the test bar 40'. At their opposite ends, they are formed for detachable engagement with the torch structure. The portions 46, 47,

straddle the pipes 9, 5, 2 and 27, said pipes being preferably all in the same plane so that the plane of the cla-mp and the bar held thereby is substantially fixed. Preferably, the clamps 41, 42 are of spring material held together as by screws 48 and clamping nuts 49, 49, preferably designed so that the bar 40 will be securely but slidably held in 'the clamping jaws 43, 44, while the mounting jaws 46, 47 will be securely held to the pipes, for ready attachment or removal. To facilitate the attachment, the outer ends 46a, 47 a. are preferably cui'ved outward as shown.

-From the statement of the nature and objects of my invention, first above given, the uses of the above described apparatus will be obvious. The above-water source of supply through hose pipes 3, 7 and 83 requires no special cont-rol provided only the pressure be in excess o the maximum pressure required at any depth at which it is proposed to Work. The diver will first turn on and adjust one ofthe gases as, for instance, the hydrogen, to get a suitable length of cavity in the Water land will then note the proper setting of the valve which he then closes. He will then do the saine thing separately for the oxygen and for the air, adjusting for the length of bubble of each which he knows by experience will be necessary for the predetermined adjustment of the hydrogen. Then turning on all the valves to the predetermined settivng, the mixture may be ignited in any of the usual ways as by an electric sparker inserted in the bubble. The test bar may be applied as shown in Fig. l sothat in full view and at closest range the diver may further adjust the oxygen and hydrogen by means of valves 4 and 8, until the flame is exactly right and heats a white hotspot on the bar. If desired, he may then test the oxygen cutting jet by manipulation of trigger l() to cause combustion of the liron or steel. Having thus attained desired operation on the test bar at the desired depth, he will then apply the torch with the gauge surfaces 37 in contact with the metal to be cut, with the certainty that maximum heating and cutting effects will be obtained. The

test bar and method of using the same is not specifically claimed herein, being reserved for another application.

It will be understood that an under-water torch constructed in accordance with my invention will be of great use in many other industrial operations besides salvaging ships and the like. F or instance, the torch may.

be used by a fireman for cutting girders, etc. during a fire, while they and the torch are protected from the fire by floods of water from the fire hose; or, the torch may be used indiscriminately for cutting metal above or under water in a cellar which has been Hooded in attempts to put out the fire.

A more conventional commercial use constituting a distinct invention, is the shaping of refractory metal castings as, for instance, chrome steel, by subinerging such castings in a suitable liquid and then using my torch for cutting the submerged casting to shape. In this way, the heat maybe localized so that the cutting torch can be used to shape the surface, yet the liquid will confine excessive heating and damage of quality to a very thin layer of the metal adjacent the cut surface, leaving the rest of the metal unaffected. For this purpose, hydrogen gas giving a temperature somewhere near 2,500 F. is distinctly preferable to acetylene, which gives temperatures nearly 1,000 degrees higher.

, I claim:

l. An under-water cutting torch having a burner nozzle for discharge of an oxygenfuel gas mixture, a substantially cylindrical sheath terminating in a nozzle for surrounding the same with a sheath of air or the like, in combination with a gauge mounted for adjustment lengthwise of said burner nozzle, said gauge comprising diainetiically opposite portions of equal length projecting endwise beyond the nozzle and endwise adjustable by a screw-threaded mounting on said nozzle.

2. An under-Water-cutting torch having a burner nozzle for discharge of an oxygenfuel gas mixture, a nozzle for surrounding t-lie saine with a sheath of air or the like, the passages for discharge of the oxygen, the fuel gas, and the air, being approximately parallel in combination with a gauge mounted for adjustment lengthwise of said burner nozzle, said gauge comprising diametrically opposite portions projecting vendwise beyond the nozzle and having a screw-threaded mounting thereon, and means for independently supplying and adjustably controlling oxygen, fuel gas and air to cool the torch nozzle.

3. rlhe method of adjusting an oxygenfuel gas flame surrounded by an air sheath, for under-water cutting, Which method includes adjusting the proportions of the gases by separately and successively projecting and adjusting the pressures of uuignited jets of each, at substantially the depth at which the cutting is to be performed to obtain a desired ratio of lengths for the respective bubble cavities formed by'each gas separately, then simultaneously supplying all of the gases to their jets at the respective pressures thus predetermined. j

"1. The method of under-Water cutting of metal, which includes producing and maintaining a flame of minimum turbulence by supplying the mixture of gaseous fuel and oxygen to the flame through a plurality of parallel circularly arranged jets, protecting said jets and the flame by a surrounding air jet discharged approximately parallel with said jets; and adjusting the proportions of the gases b jecting andyadjusting the pressures of unignited jets of each, at substantially the depth at which the cutting isto'be performed to obtain a desiredratio of lengths for the respective bubble cavities formed by each gas separately, then simultaneously supplying all of the gases to their jets at the respective pressures thus predetermined;

Signed at Westfield, in the county of Union, and State of New Jersey, this 15th day of November A. D. 1927. y

EDWARD ELLSBERG.

separately and successively pro-

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