US1679586A - Tip for cutting torches - Google Patents

Description

' UNITED STATES f PATENT 'oFFlcE.-ij

GEORGE c. QUELcII, ofE oAxMoNT, PENNSYLVANIA, AssIGNoR To INTERNATIONAL -I oxYeEN COMPANY, or NEWARK, NEW JERSEY, A coRPoRATIoN 0E uNEW JERSEY.

TIP EoR CUTTING ToRcHEs.

Application led Decemberl, 1926. Serial No. 156,210. I

My` invention refers t o an improvement in the class of cutting tips for torches for 'the cutting of ferrous metals.

Inlsuch torches, which are now in large` corresponding ccssation of the preheating flame. f

`Combustion of the metal, under the oxy-` gen jet, then occurs, reducing the metal to magnetic oxide of iron, the pressure ]et of oxygen forcing the oxide throughl andv away from the narrow kerf made in the metal as the cutting actionproceeds along a given line. i

In torches of this generalA class, the device is usually provided with three supply pipes orrl conduits,l leading to the terminal head embodying the tip, providing for the supply of high pressure oxygen for cutting, low

pressure oxygen, `and a combustible gas for burning therewith for prheating.

In general practice, there are two mainl classes or types of tips utilized; first, where the combustible mixture of oxygen and fuel gas, for -preheating, is formed or combined' within the torch proper 'or within`its hea-d; second, where the combustible mixture 1s formed between balanced gases, or by proper relation of the conducting orifices, or. b injector action within the torchG tip itsel mounted in the surrounding head.

There are also variations in the terminal construction of thetip, which may be either plane across the delivery end with all of the jet openings emerging on the same plane, or with the tip of the jet recessed, providing a forwardly extending tubular shell for protection of the preheating flame.

'Ihe plain end tips'are ordinarily used for fuel gases having a kindling or igniting point below 600 C., such as hydrogen igniting with an igniting point of 580 vor acetylene at 480 C. A. Y

The recessed tips are odinarilyused for fuel gases having a kindling o r ignitingv point above 600 C., as in the case of hydrocarbon gases, which-liquefy Within a container at -or below` the pressures usually considered standard for-'low or high pres-l. silre containers.

In the use of such gasesfor metal cuttingwith torches of the class involved,.it has been necessary, and the practice is common 1n theV 1ndustry, to use. a tip designated. as a recessed or cup tip. V.

The object of my present invention is to provide a cutting torch tip for the pur ose of securing a more stable preheating am with a gaseous mixture of high kindling or igniting point, as above 600 C.

lso, to provide a' cutting torchi'ti for` use with natural gas or other gases o similar high kindling quality adapted for use, with oxygen, in cutting and like operations.

One of the objects accomplished by the construction shown is to provide for .an alternating path for gas circulation, or for gas and a small oxygencontent, through an alternating course, with channels and mixing cavities.so arranged as to eilect a complete and thorough mixture of the` gaseous body, in such alternating or tortuous path.

Also, to provide beyond such zone of uniform density, contracted outlet ports which re then enlarged to increase the area of the outlet ports for expansion of the gases before emission; and enlarged final emission areas at the ti'p terminal, surrounding the main oxygen supply port, and on the same transverse plane therewith.

By the construction involved, I effect a desirable uniformity of density of the gaseousmixture, at the point of combustion. I alsov avoid the necessity of recessing the tipi ory its'ca'sing, thereby preventing burning, and lengthening its available time of use.

These objects aie secured by providing the individual preheating gas delivery passages,

with alternating or intervening communicating admixture pockets and final terminal delivery channels adapted to conduct the gaseous mixture under uniform pressure and with such accelerated terminal delivery. In the construction shown, these features are embodied in both of the main classes of tips above identified, and as hereinafter more fully described.

In the accompanyingI drawings, showing certain preferred embodiments -of the inv vention: f

Fig. 1 is a sectional view of the fhead of,

- cutting torch, lof the first class, provided lill of Fig. 2;

with one form of my improved tip;

Fig. 2` is a similar sectional View of another construction of tip and its mounting, of the second class, partly in elevation;

Fig. 3 is a cross-section on'the line III- F'g. 4 is an end view of the tip of Fig. 2;

Fig. 5 is a .partial longitudinal sectional View on the line V-V of Fig. 2;

Fig. 6 is a cross-section on the line VI-Vl of Fig. 2; and e Fig. 7 is a similar View on the line VII- Vfl of Fig. 2. .W Referring to the drawings, A is the head of Ia standard torch having the usual high pressure oxygen pipe 2, a low pressure oxygen pipe 3, and a gas supply pipe 4 communicating with the .several corresponding passages 5, 6- and 'l'.

As is generally understood in the art, the preheating mixture is effected by mixing the low pressure oxygen from port 6 with the preheating gas, as acetylene, hydrocarbon, etc., of passage 7. The jet member of the present invention, for such construction, is adapted to be mounted in head A. in connection with its integral inner distributing head or member -as similar` tips, having a central opening from one end to the other forthe passage and terminal emission of the high pressure oxygen supply, with -outer terminal surrounding enission jets for the preheating oras.

.b In the form shown in both cases, Figs. 1

and 2, such tip is enclosed within an outer surrounding shell or enclosing tube 14 fixedly held in contact with the confronting flange of member a by a threaded fitting 12.

Otherwise, as in Fig. 2, the tip is provided with a terminal threaded inner end 13, for insertion within the headB. v v Shell 14 in such case is co-operatively mounted with any suitable similar fitting 12. With either construction, I provide; a

' series of annular'abutments 15, with alternating reduced connecting neck portions 16 of the tip member, providing annular mixing chambers 17, between the several abutments. The abutments 15 are provided with longitudinal circulating ports 18, said ports preferably alternating in longitudinal arrangement, as shown, whereby Jto provide a tortuous progressive path for the combustion mixture from its introduction into the initial of such abutments and intervening admix ture chambers'may bel provided, dependent on the conditions, kind ofgas used, etc.

The outer end of thetip is tapered, as at 19, for interfitting connection within the outer tapered portion 2() of shell 14. Such tapered porti/on of the tip is longitudinally grooved as at 21. Any suitable number of such grooves may beprovided, preferably six, equally spaced aroundthe central oxygen outletopening- 8, providing an enveloping or surrounding sheath of preliminary heating gas. Y

Each of such channels 20 is enlarged at its middle portion, as by a milling cutter or other suitable tool, so as to increase the depth of the groove, as indicated at 22. The cross sectional area of. the groove is maintained uniformfrom such deeper portion toward the end, however, whereby to provide open unrestricted delivery ports for the gas with decreased velocity, as it nears the exit opening.

The ends of the channels -20 are finally materially enlarged, as indicated at 23, as

enlarge the cross sectional emission opening for the combustion mixture. Any suitable formation may be'utilized, as by flaring the walls of the channels 21, so as to deliver the combustible mixture outwardly at further decreased velocity through the end of the tip on the same transverse plane asthe high pressure oxygen hole 8.

The shell 14 fits tightly around .the circular exterior'of the tip, as in Figs. 1 and'2, making close contact with the several enlargedabutment portions 1 5, and with the tapered terminal 19, thereby providing closed interior passageways for the gas.

The purpose of interposing the severalabutments 15 between the alternating annular spaces 17, and especially with the off'- set or non-registering channels 18 through the abutments, is to provide for thoroughradmixture of the gaseous mixture, and to promote and ensure a common and continuous degree of densityI throughout, with uniform pressure, from one end of the tip towardthe outlet end.

At such outlet end the volume of gaseous mixture in the final chamber 17 passes outwardly through channels 21, with such uniform' pressure, in passing therefrom into the laterally enlarged emission` apertures 23.

There is, as a result, an ample supply of gaseous mixture, with no tendency for the flame to blow away from the end of the tip when a given quantity of gases are passing through the preheating holes, as would be -by an end milling cutter or drill, adapted to perature.

' in volume of the p nal, in either ci the constructions shown, and

'effected by lowering of est sequent increase in',preheating time.

thel case if the passages 21 were continued' uniform through to the end, as is the comvinon practice.

I am', therefore, able to deliver the vpregh the end of the tip high pressure cutting oxygen, necessity of any shrouding or protecting tubular extension minals. As a result, there is no tendency for the preheating flame to be disturbed when the cutting jet of oxygen is operating, as is the case when such recessed tip is used.

My experiments with hydrocarbon gases, and particularly natural gas, having a high 'kndling or' igniting temperature, have shown that with a cutting equipment designed forl gases of low kindliig point, a flame cannot be held at the end of a plain tip, unless the flame were highly oxidized. Such over-oxidation is objectionable because it materially reduces the flame tem- When ahydrocarbon proper proportion of oxygen, to secure maximum liame temperature, the flame will not burn continuously yat the end of the tip, unless the volume is decreased to a fraction of the volume for which a givensize tip was designed. ASuch decrease of volume is pressure, so that a hydrocarbon gas of high ignition point will burn at the end of the tip if the pressure or velocity of the mixture at the point where the gases leave the tip, is thus lowered.

It is well. understood that 4it is necessary to burn a comparatively large' volume of combustible gas` mixture in al small areain order to raise the temperature of the metal locallyto the combustion point in the shortpossible time. The lowering of pressure at the end of the tip when elected only by a lowering in volume necessarily decreases the capacity of a given Size tip, with acon- In my invention I secure the desired lowering lin pressure, without any decrease hydrocarbon fuel gas mixed with the proper proportion of oxygen, and secure the maximum ame temperature obtainable. This result is directly due to the preliminary bustible gas elements in the alternating channels, vand to the zonalenlargement the individual jet passages themselves, and .the final enlarged discharge orifices for a short distancef'b'ackwardly of the tip termias above described. i

It will be understood, of course, that the mixture passages may number and arrangement vof thel surroundine be changed or vari beyond the passage ter,

gas is mixed with a complete admixture of the com-' within the judgment of the designer orv skilled mechanic, and with regard 'to the kind of work to beperformed andthe gaseous mixture employed. I, therefore, do not desire to be limited to the particular construction shown, but to include such variations withinthe scope vof the 'following claims.

What I claim is:

l. In a cuttin torch, the combination with y an enclosing s ell having a` central high pressure oxygen supply port and laterally arranged low pressure oxygen and gas supply ports respectively, and an enclosing shell connected with said head, of a. cutting tip having a central oxygen conduit communieating with the central port and an inner reduced neck providing an annular chamber with ports leading therefrom to the laterally arranged low pressure oxygen and gas supply ports, a plurality of annular abutments and reduced 'neck portions alternately located beyond said annular chamber, each of said abutments having a pair of oppositely located longitudinal ports arranged alternatingly between similar ports of an adjacent abutment,.wth la iinalterminal abutment within the endmost portion-of the casing havingan annular series of iinal delivery channels leading from the endmost annu-y lar chamber to the end of the cutting tip,

larged towards their middle portion without said delivery channels being outwardly ensubsequent diminution. and' having further enlargedl outlet terminals ending on the plane of the end of the shell.

` 2. A cutting tip of the class described hav;

ing a central oxygen conduit adapted to communicate with a central supply port, a tapering head having ports adapted to' communif seijes of final delivery channels leading from'` thaendmost annular chamber to the end of the cutting tip,

portion without subsequent diminution and aving further enlar ed outlet-terminals ending on the plane o the end of the tip.

In testimony whereof I hereunto aiiix my signature.

GEORGE C. QUELCH.

said delivery channels being outwardly enlarged towards their middle iio

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