US1901428A - Method of cutting metal by means of gases - Google Patents

Description

March 14, 1933. J. 1.. ANDERSON HETHOD 0F CUTTING METAL BY MEANS OF GASES Filed Dec. 13, 1950 2 Sheets-Sheet l J. L. ANDERSON METHOD OF CUTTING METAL BY MEANS OF GASES March 14, 1933.

2 Sheets-Sheet 1 Filed Dec. 15 1930 1 NTOR 5/ ATTORNEY Patented Mar. 14, 1933 amaze;

U ITED STATES PATENT OFFICE urns L. summon, or many, new 3mm, assmuon no em. annucrxon ooxrm, mconromrrm, or new Yonx, 1w. 1. .0. oonronarron' or now somemzon or corms Maren :5! ms or cases Application and December 1a, 1980. Serial No. 502,096.

This invention relates to a method of out I ting metal by means of gases and to apparatus therefor.

- The cutting of members such as those of 6 H or I cross-section is an important application of the invention, and is the one illustrated herein. However, the invention in its broad aspect may be understood as having- .reference to the cutting of members which, although otherwise of substantially uniform cross-section, have at some one or more 0- sitions in the extent thereof a web or 0t er decided increase in cross-section. Such increase has under pastconditions of o ration produced an undesirable result w en the member was cut by a jet of oxygen gas directed at the metal to form a slot extending transversely of the intersection of web with the body of the member bein out.

forth it has been customary to dispose the cutting jet substantially perpendicularly to the surface of the member; in some cases the jet has even been directed angularly' in the direction in which the jet was moved, a method commonly used to counteract, to some degree, the lag of heat conduction through the metal.

' In these operations the jet was first directed to cut through the main portion or flange oi the memberyit was then moved transversely of the flange, and toward the intersection of the flange and the addition or web. At such intersection the increased thickness of the metal reacted upon the jet in such manner that the face of the cut produced was not'even. The increasedcross- I section of the metal wouldmake the preheating eiiect of the flame jets preceding the cutting jets insuficient for complete penetration by the cutting jet. The cutting jet would continue to cut the ordinary slot as long as possible, and then, as the resistance of the increased section balked further penetration, the gases seeking an outlet would turn back upon themselves and seek escape "upwardly out of the cut and in effect envelop the jet. As can readily be understood,

thcefiect of such gas behavior would be to 53 cause the oxygen to cut away metal from the In cutting members 0 the character set ly those metallic forms in which a portion of wall of the cut in addition to that originally oxidized by the direct blast Churning of the gases within the cut resulted in the formation of a cavity in the web, having dimensions much-larger than those of the desired kerf, or at least caused ragged and irregular cutting into the web. Subsequent machining of the cut end of the member to the complete depth of the cavit was necessary, and this involved an excessive waste (if material and time tobring the cut fsiqe .to the form required for structural work in which. such members are used.

It has also been found that the cut ng jet has had the efiect of drawing through he cut with itself the cold, non-combustible air gases, and in such manner to form a'blanket around the cutting jet which would be detrimental to continued combustion of the metal. The dead nitrogen of the air acted to rob the metal of heat necessary to attain the desired temperature of metal combustion.

lt-is an object "i this invention to provide a. method of editing metal, and especialsubstantially uniform cross-section is joined by one-or more webs, or fins, or like enlargements or lateral extensions, in which the cutting j at is so disposed that, when it encounters an one of the intersections, the kerf will have su stantially the same formation as that produced by the jet when cuttingfiange metal only. To accomplish this result, the cutting jet is directed at an inclination to the surface over which it moves reverse to the course of travel of the jet relative to the metal surface, in other words by inclining the jet backward. By so disposing the cutting jet, and either continuously or at the particular time when the jet is cutting through theincreased metallic CI'OSSrSGCtlOIl. by discharging through the jet an excess of the oxidizing gas over that determined by the amount of gas necessary to cut metal of flange thickness only, and in a preferred method also by heating the metal in advance of the cutting jet to a greater degree than would ordinarily be necessary for efiective cutting of metal of flange thickness, the "cutting of the flange and the intersection metalmay be accomplished quickly v scri d, nor to the specific method, as the and without interruption and without any undesirable cut formations. j

It is a further object of the invention to dispose preheating jets for the cutting operation in such manner that the hydrogen envelope gases produced thereby will dis lace the air ordinarily drawn through the s 0t, and thus rovide a combustible sheath for the cutting et which will be efiective to heat the metal within theslot and facilitate cutting at great depths to which the ordinary preheatin jets would not supply the necessary heat to acilisame may be modified in various particulars without departing from the scope and spirit of the invention, one particular execution of which has been illustrated and described, without attem ting to show all the various forms and mo ifications by which the invention might be carried out.

In the drawings:

Fig. 1 is an elevational view, partly in sec-,-

tion, illustrating in' connection with theeutting of members of H cross-section applications of the old method and of a method embodying the invention;

Fig. 2 is a plan view of a face of a member such as shown in Fig. 1, illustrating the cut produced by the old method;

Fig. 3 is a bottom plan view 'of a torch usedin applying the invention; and

Fig. 4 is a vertical longitudinal view through the body of such'torch.

In Fig. 1 there is shown an H-column 10 sectional consisting of-a web 12 and integrally formed flanges 14 and 30. In this figure an ordinary cutting torch 16 has been disposed to direct a jet 18 of oxygen at the flange 14, in the customary manner, that is, substantially perpendicular to the surface of the metal upon which it acts. it hastbeen-found that the penetration of heat applied to the surface of the member to be cut by the preheating jets 20lags to such extent that the cut, produced by jet 18, is substantially of the character shown in Fig. 1, that is. a out which at the point of impingement of jet 18 is substantially perpendicular to the surface of the flange but which ta rs oif into the curving surface 22 and the, e edge 24 before the gas from jet 18 issues forth from the out. This isthe normal contour of the breast of the out, where the oxygen jet is continually advancing, transversely to itself, into new metal. For the purpose of illustration the breast of the out is shown ahead of the jet,

, centuates the difliculty presented by the In the ordinary procedure nt an actual condition. When the jets arrive at the intersection of web and flange this lag acgreat- 1 increa'seddepth of metal, with the result t at the as, instead of continuously burning off the e go 24, is not only quite incapable of penetrating to the full epth of the web, but, in attempting to dig into the web, mere ly churns around within the cut that has been made, and the excess of the o'xidizin gas acts to burn away additional metal on either side of the out. A recess, such as shown at 26, is thus produced before the jet gases burst forth but of course this does not represe on the o%posite side of the web to continue e other part of the flange in the cutting t customary manner.

V Attempts have been made too rate with the cutting jet impinging oblique y upon the metal in the*direction of movement of the jet relative to the metal, but this roduces even worse results in the way of poo eting at the web than when'the jet is perpendicular or substantially per endicular to the flange.

Cutting in accor ance with the invention is illustrated in connection with the other flange 30 of Fig. 1 and the adjoining portion of the web. The cutting is performed by a torch 32 constitutin oart of the invention.

The torch prefera ly comprises a tip body 34 having an orifice face 36. Opening through the face 36 are a plurality of orifices 38, disposed in a single file, the number thereof being determined in accordance with the thickness of metal to beoperated upon, the speed of cutting, and other similar factors. -Rearwardly of orifices 238, face 36 is cut out into a plurality of recessed portions 40, forming faces 42, angularly disposed so that orifices 44 drilled into the body of such' faces will direct gas jets 46 at the flange 30 substantially oppositely to the direction in which it is intended to move the torch over the flange. Orifices44 are drilled in pairs, equally spaced from the line of orifices 3 8, for the purpose hereinafter a peering.

Body 34 is formed with anot er an rly disposed face 50, the disposition of w ich is similar to that of faces 42, and from which opens orifice52 to direct a single et 54 of pure oxygen at themetal in a direction substantially parallel to jets 46 but along sub-- stantially the same line of metal surface as was heated directly by from orifices 38. i Gases for the jets at orifices 38 and 44 are the gas jets issuing fed through individual bores or drilled o nings from apassage 56 in body'34, whic is supplied with a mlxture ofvoxygen and some fuel gas, such as acetylene, under ressure, so that a "plurality of oxy-fuel gas amejets are directed from these orifices upon the metal. The passage or chamber 156 ji u plied with the mixed gases throughpa g 61, 62 f om a mixer forming part 'of-"th torch. The mixer and the conduits for leadingthe gases to the mixer need not be illustrated, since such matters are well understood. The cutting jet 54 is fed from anindividual' passage 60 which is connected in a usual way with the oxygen supply to deliver a stream of pure oxygen through this orifice.

The jets 58 from orifices 38' serve to heat directly the metal along the proposed line of cut. The burning hydrogen envelope gases from these jets spread out over the laterally adjacent metal and serve to heat the metal, considerably spacedaway from the line of jeis, to a fairly high temperature,

Jets 46, however, are dis osed at 'a marked distance on each side of te line of jets 58. Concentration of heat in the neighborhood of jets 46 is important as the jet 54 immediately follows them. The laterally spaced jets, in addition to other advantages gained, facilitate such concentration. Radiant heat from the inner sides of the spaced a art jets is added to the heat already put in a ong the line oi cut by the jets 58. Furthermore, jets 46 by their angular disposition bring their very hot side portions into moredirect con tact with the surface of the metal, without losing any substantial portion of the effect arising from the hot flame tip. Radiant heat from the jets is also more efiective since heat, radiated substantially perpendicular to the directionof the jet is brought to hear directly upon the metal surface.

Since flame jets 46 are directed toward the position at which the jet 54 issuin from orifice 52 is located, the unconsumed ydrogen envelope gases, which are liberated in greater quantities because of the inability of stones herio oxygen to reach them, will be force to travel alongthe metal surface toward the point at which the cutting jet 54 impinges. Afters out has been initiated by jet 54, the rush of gas produced by this jet will be efiective to draw'into the cut 62 such:

hydrogen and carbon monoxid envelope gases as move into its pathfrom jets '46. The combustion of the oxygen and these envelope gases within the cut produces a heat- 4 ing oi the metal in closer proximity to the metal to be burned than can be effected by jets disposed on the outer surface of the met- 81, a result especially desirable in cases of metal of great thickness since the heat created is applied iediately as cutting proceeds and immediately to the metal that is to be cut. Hydrogen, as is well-known, because of its extremely long flame, is very effective for the desired purpose, its flame extending well down into the kerf, preheating the oxygen which has become chilled by its expansion at orifice 52. The slag formed by the cutting action is maintained in greater fluidity than occurs by the customary methads of operation, since it is bathed in an atdi?osition of jets is on either side of the line 0 jets 54 and 58 serves also to enable jet 54 to operate with a minimum disturbance and deflection arising from the action of the ases moving away from 'ets 46 and, in eflect, m slight tangency with-t e side edges of the oxygen jet, a result which would not be as efl'ectual if only a single file of jets, disposed as are jets 46', were utilized. Y

7 The efiect of disposing the cutting jet 54; at a rearward inclination is as follows: the torch moves over the surface of flange 30 and the oxygenjet is required to act upon the increased cross-section at the intersection of the flange and the weblQ, the out, which originoted in the dan e, will continue through flange and. web, the gradual increase in the efi ective depth of the out being compensated for as the reactionproceeds. Since no barrier to continued cutting as great as the length of the web is suddenly interposed during the cutting action, but rather a gradjet 54 should he direct-ed obliquely oppositely to the direction of travel of the jet relative to the metal; however, the jet may also'be dis osed at a double inclination, longitudina y and laterally, to make an angular cut in the flange and web, that is, a cut the faces mosphere eta. reducing gas such as hy xll rhogen.

of which are'not perpendicular to the surinvention hereof.

The rearward obliquity of the cutting jet. 54 to the face of the metal, that is to say the obliquity in the plane of movement at right face of the metal out-and yet embody the angles to the surface, as represented in the drawings, is to be understood as being a decided inclination, on the order of 45, or somewhat more or less. The particular angle may be varied in accordance with the angular relation between the flange and web, or other parts corresponding to these, their relative thickness, and other considerations, an inclination 45 being typical. The oblique heating jets 46 are delivered at a similar pronounced inclination, though their inclination may be made to form a lower angle with the face of the work in order to impel their combustible envelope gases more definitely to the region where the cuttin jet is forming the lierf, or with somewhat less advantage the r inclination may be made less acute.

By discharging through jet 54, either continuously, or immediately that it comes to the intersection, a considerable excess of the oxidizing gas, cutting of the web metal may be continued, after the jet has passed beyond the intersection, and even though such metal is no longer directly connected to the flange metal beingrcut and has lost the efl'ect of contime will-continue cutting the web metal to' produce a kerf, continuing the original slot, made as the jet crossed the web.

In cutting beams and columns, either integral or built-up o the torch will be moved in relation to the work, In other cases the work may be moved past a stationary torch, in which event the inclination of the cutting jet will be in the direction of movement of the work, which is the same thing as inclining the jet reversely to the direction of movement when it is the torch and not the work which is moved lOther modifications of the process and apparatus will suggest themselves to those skilled in the art.

I claim:

1. A method of cuttin continuously across the flange portions 0% metallic members formed by the intersection of two plate-like portions, in which at least one of such. rtions terminates at the intersection, w ch includes: directly obliquely at the flange portion a jet of an oxidizing gas in quantities greater than necessary to penetrate only the metal of said flange, eflectlng relative movement of the flange portion and the oxidizing gas jet so that the direction of the jet is o posite to the movement thereof relatlve to t e rtion, and acting on the metal of the flange in advance of such jet with an extensive series of successive preheating flame 'ets, art at least of said preheating jets being irected oxidizing jet.

. of such jet with preheating 2. A method of cuttin the flange portions 0 metallic members formed by the intersection of two plate-like portions, in which at least one of such portions termintes at the intersection, which in- 'cludes: eflecting relative movement of the flange portion and an oxidizing gas jet, and

acting on the metal of the flan e in advance ame jets, the combustion products of which include a" combustible gas, said preheating jets being laterally spaced and inclined rearward so as to provide a supply of such gas which is impelled mto the path of the oxidizing jet.

3. A method of cutting continuously across the flange portions of metallic members formed by the intersection of two plate-like portions, in which at least'one of such portions terminates at the intersection, which includes: directing an oxidizing gas jet obliquely at the flange portion, effecting relative movement of the fla oxidizing gas jet so that t c direction of the f H or I section, or the like, I

continuously across tion of portion and the jet is opposite to themovement thereof relative to t e portion, and act' on the metal of the flange in advance of su jet with pre-' heating flame jets.

'4. A method of cutting continuously across a flat surface portion having a formation ex tending from said portion on the side obversel of said flat-surface, the line of cut exten ing transversely of the intersection of said portlon and formation, which includes:

directin obliquely rearward at the flat surface of t e portion a jet of an oxidizing gas in quantities greater than necessary to penetrate only the metal of said portion, and effectin relative movement of the portion and the oxidizing as jet. 1 5. A method of cutting a metallic member along a proposed line, in which relative motion of the member and an oxidizing jet is eflected, which includes: heating the metal of the member by means .of forward .heating. jets directed to play stantially in line wit the line of the out, directing a plurality of other heating jets ohliquely rearward at the metal on each side of the previously heated metal, and finally subupon the metal subjectmg the metalto the action of the oxidizmg et substantially along the initially heatedline.

relativermotion of the jets and the member is effected, the direction of said oxygen 10b and part at least of said preheating jets be ing oblique to, and in opposite direction to,

the movement of the jets relative to the memobhquely in the same general sense as the be 7. A method of cutting a metallic member b means of an oxidizing gas et, wherein: tlie metal is preheated by a plurality of flame jets, the products of the combustion thereof including hydrogen, the oxygen jet is obliquely directed rearward at the preheated metal, said flame jets are laterally spaced and directed obliquely rearward at the metal, and relative motion of the-jets and the member is eflected.

8. A method of cutting metallic members along a roposed line, in which relative moe member and an oxidizing jet is effected, which includes: heating the metal of the member by a series of forward heating jets acting substantially in line with the line a of the cut, directing a plurality of other heat-- ing jets at the metal on each side of the pre-'- viously heatedmetal, and finally subjecting the metal to'the action of; the oxidizing jet substantially along the initially heated line. JAMES L. ANDERSON.

jet is directed at the preheated metal, and 19 6. A method of cutting a metallic member 5' j

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