US2208139A

US2208139A - Apparatus for flame machining

Info

Publication number: US2208139A
Application number: US192355A
Authority: US
Inventors: Herbert E Serner
Original assignee: Union Carbide and Carbon Corp
Current assignee: Union Carbide Corp
Priority date: 1935-05-07
Filing date: 1938-02-24
Publication date: 1940-07-16
Anticipated expiration: 1957-07-16

Description

Jy l, 130. s R R 2,208,139

APPARATUS FOR FLAME MACHINING Original Filed May 7, 1935 3 Sheets-Shem, l

I INVENTOR. HERBERT E SERNER BY ATTRNEYV Y W, H. E. SERNER APPARATUS FOR FLAME MACHINING 3 Sheets-Sheet *5 Original Filed May 7, 1955 v INVENTOR HERBERTLSERNER BY I ATTORNEY Patented July;16,1940

UNITED STATES APPARATUS FOR FLAME MACHINING Herbert E. Semer, Oakland, N. J., assignor, by

mesne assignments, to Union Carbide and Carbon Corporation, a corporation of New York Original application May 7, 1935, Serial No. 20,167. Divided and this application February 24, 1938, Serial No. 192,355

11 Claims.

This invention relates to an improved apparatus for flame machining wherein heated metal is removed from the surface of a metallic body by progressively applying a plurality of oxidizing gas streams simultaneously to successive portions of such a surface. More particularly, this invention relates to apparatus for flame machining surfaces of metallic bodies to produce shaped surfaces having a predetermined contour.

This application is a division of my Patent No. 2,125,180, issued July 26, 1938, for an improvement in Method of flame machining.

In starting a flame machining operation to remove metal, a portion of the surface is heated sufliciently to produce ,a wet surface film of molten metal. When an oxidizing gas stream is applied to such wet film, it tends to spread over an area of surface metal that is subjected to the influence of the oxidizing gas stream. This wet film or puddle, which comprises a mixture of molten metal and oxidized metal, is believed to be essential to enable the oxidizing gas stream to penetrate into the metal to melt and oxidize the same. The heat of reaction resulting 25 from the oxidation of molten metal heats metal ahead of the oxidizing gas stream so that, when the gas stream is progressively applied along the surface, a wet surface film is always produced at the areas acted upon by the gas stream.

Although I do not wish to be held to the exact theory of flame machining just described, constant observation and study of flame machining noperations does indicate that the wet surface film produced is essential to maintain a cut and 35 remove metal continuously from successive portions of a surface.

In accordance with my invention, surfaces having a predetermined contour are produced by flame machining by controlling the shape of the 40 wet surface film and the manner in which it is formed at successive surface portions from which metal is to be removed. In the presen application of my invention a plurality of oxidizing gas streams are utilized to control and maintain a single wet surface film or puddle, with one of the streams applied to a surface at the rear of a preceding gas stream to produce the desired cut in a single pass of the gas streams relatively til to the metallic surface. By this method surfaces chining whereby surface metal can be removed from an edge surface of a metal body in such a manner that any predetermined surface contour thereon can be produced; and to provide an improved apparatus for holding and guiding scription proceeds, and the features of novelty which characterize my invention will be pointed out in the claims annexed to and forming a part of this specification.

In the drawings Fig. 1 diagrammatically illustrates one manner of applying two oxidizing gas streams at the edge of a metallic body to coact and produce a smooth out; Fig. 2 is a view taken at line Z2 of Fig. 1 to illustrate more clearly the contour of the surface produced; Fig. l

3 is a view similar to Fig. 1 and diagrammatically illustrates the action of two oxidizing streams which coact to produce a cut having a contour different from that produced in Fig. 1; Fig. 4 is a view taken at line 44 of Fig. 3 to show more clearly the type of cut producedaFig. 5 is a perspective view of the metallic body shown in' Fig. 1 to illustrate more clearly the manner in which the metal is removed to produce the cut; Fig. 6 is a sectional view of a nozzle for use with the apparatus of this invention taken at line 6-6 of Fig. 7; Fig. 7 is an end view of the nozzle taken at line (-1 of Fig. 6; Fig. 8 is a sectional view of the nozzle taken at line 8-8 of Fig. 7; Fig. 9 is a side view, in elevation, of apparatus embodying my invention in which the nozzle shown in Figs. 6- and '7 is employed to produce cuts of the type illustrated in Fig. 2; Fig. 10 is a plan. view of the apparatus shown in Fig. 9; Fig. 11 is a sectional view taken at line "-4 I of Fig. 9; Fig. 12 is an end view of the apparatus in Figs. 9 and 10, taken from the nozzle end; and Fig. 13 is a sectional view taken at line I3l3 of Fig. 12. l

The method of removing surface metal by employing a. plurality of coacting relatively low velocity, oxidizing gas streams is more fully explained in and is claimed in the patent previously referred to.

In flame machining it has generally been the practice to employ a nozzle having a single circular or an elongated discharge orifice for delivering an oxidizing gas stream, and the present method of flame machining can be efiectively carried out by utilizing a plurality of such nozzles. By varying the shape of one or more of the discharge orifices of the nozzles employed, changes in the contour of a out can readily be produced. In place of several independent nozzles it may be preferable in some instances to employ a single nozzle having a plurality of discharge orifices capable of delivering oxidizing gas streams which will coact to produce a smooth out of a desired contour.

' In Figs. 1 and 2 I have diagrammatically illustrated one manner of practicing the method of flame machining to produce a smooth surface having a predetermined contour. The surface contour shown at the edge of plate III in Fig. 2 is particularly desirable for electrically welding two of such plates. It will be noted that the portion ll of the edge surface has a sharp radius of curvature and that the portion It extends down-,

ward therefrom in substantially a straight line which is at an angle to the original edge or uncut portion I3. When two plates having such an edge surface contour are arranged edge to edge, a U-shaped groove is formed which will permit a welding electrode to extend therein with its fusing end adjacent the very bottom of the groove. This will insure an arc being established between the bottom of the groove and the end of the electrode rather than between the side walls of'the groove and the electrode; and when the former occurs a sound and firm weld deposit is obtained.

To make a cut which will produce the surface indicated at H and I2 in Fig'. 2, a plurality of positioned at a slight acute angle to the edge I3 F and in such a directionthat the metal removed is blown ahead of and sideways of the cut as it is being made. a

The oxidizing gas stream 1) is so applied that it efiects the first removal of metal from the edge of the plate I0. As-shown in Fig. 1, the gas stream b'strikesthe surface about a third of the distance from the top surface of the plate l0.

Assuming the surface metal to be sufiiciently heated to have a wet surface film formed thereon, melting and oxidization immediately take I place, and surface metalin the form of slag is blown ahead of and sideways of the cut, along the surface, by the force of the oxidizing gas stream. g

' The oxidizing gas stream a is applied on the surface of the plate l0 adjacent the uncut portion It thereof. The gas stream a is arranged to. strike the edge at a greater acute angle than the gas stream b, so that it will effect the last ;removal of metal as successive surface portions of metal are removed in the direction indicated by the arrow 0. Upon striking the edge surface of the plate ID, the gas stream :1 produces the curved portion ll having a sharp radius of ourvature. The'gas stream a is deflected by, the

curved portion "that it produces, flows under the gas stream 17, and sweeps across and over the edge surface of the plate Hi. In flowing over the lower part of the edge surface of the plate It, the gas stream (1 tends to merge with the tion l2 of the cut will be substantially straight, as shown, the velocity of the gas stream a is 'sufilcient to sweep acrossand over the entire surface of the finished cut that is produced.

The action of the oxidizing gas streams a and b during a metal removing operation is clearly shown in Fig. 5. As the cut is progressively being made, the gas stream b effects the initial removal of metal from a surface portion d extending between the dotted line indicated at l8 and the point I8. Directly behind the gas stream b the gas stream a efiects the removal of a surface portion e extending between the point 20 and the dotted line It. Thus the gas stream a effects a complete removal of surface metal over the entire edge to provide a out which is exceptionally smooth with no rough portions to define the separate action of the streams a and b. A cut having a sectional surface contour as shown in Fig. 2 may be produced when theorifice I4 that discharges the gas stream a is rectangular in shape and the orifice ii that discharges the gas streams b is substantially circular in shape.

As mentioned above, the shapeof the surface contour produced can be varied by employing gas streams that are discharged from diflferent shaped orifices of a nozzle or nozzles. In order p to produce the cut shown at the edge surface of plate It! in Fig. 4, for example, two gas streamsf and a may be employed which are discharged from

circular orifices

22 and 23 of a nozzle 24. The action of the gas streams f and g are the same as gas streams a and b, described above, and hence will not be repeated here. It will be noted, however, that eventhough the gas streams merge and coact to produce a smooth out having a double curvature, the velocity of the rear gas stream 1 that efiectsthe final removal of metal is such that'the desired proiection 25 at the bottom of the cut 26 is produced.

I have found it preferable to preheat successive portions of surface metal to an elevated temperature by high temperature heating flames streams. This maybe effectively accomplished by providing each nozzle with a plurality of orifices to provide high temperature heating flames.

As shown in Figs. 2 and 4, for example, the

nozzles

16 and 24 are provided with a plurality of orifices 21 and 28, respectively, for discharging a suitable 'combustible gas to provide the heating flames. 4

Although several independent nozzles may be employed to provide a plurality of oxidizing gas streams, it is particularly desirable in many instances to make cuts with a single nozzle having a plurality of discharge: orifica. A form of nozzle which is particularly suitable to produce cuts of the type illustrated in Fig. 2 is shown in Figs. 6, '7 and 8. Such a nozzle is fully described and claimed in my copending application Serial No. 191,423, filed February 19, 1938. 7

Referring toFig. 6, the nomle N embodying the principles of this invention may have a shoulder 30 at its. inner" end. An externally threaded clamping nut 3| disposed about the pipe head, which supplies the oxidizing gas.

stance.

it it passage 33 is toward the surface.

such as oxygen or a mixture of oxygen and air, and a combustible gas, such as a. mixture of oxygen and acetylene, to the nozzle.

Disposed within the outer wall of the nozzle is a group of passages 34 which are substantially equally spaced and which extend longitudinally thereof from an inlet 35 to the discharge face 36. The combustible gas is delivered from the bIOWl' pipe head and through the passages 34, which passages are reduced in cross-sectional area at the outer or discharge end of the nozzle. An oxidizing gas passage 31, having an inlet 38 communicating with an outlet inthe blowpipe head, extends longitudinally through the nozzle and terminates a short distance from the extreme end of the nozzle. From the outer end or outlet of the passage 31 two separate gas passages 39 and) extend to the discharge face 36 of the nozzle.

The oxidizing gas passing through the passage 33 is therefore diverted into the passages 39 and 33 to provide two oxidizing gas streams. Where more than two oxidizing gas streams are deemed necessary, the nozzle may be provided with a greater numberof passages at the discharge end to provide the number of oxidizing gas streams desired.

The directions in which the oxidizing gas streams are discharged and applied on a metallic surface will depend upon the particular surface contour desired. In the present embodiment, in order to produce the surface contour shown in Fig. 2, the circular gas passage Ml is inclined to the passage 31 in a direction away from the rectangular-shaped passage 33, as shown in the vertical sectional view in Fig. 6. The rectangular-shaped passage 33 is also inclined to the concentric passage 31 in a plane transverse to or at right angles to the vertical plane shown in Fig. 6,

a and its outlet is ofiset laterally from that of the passage 33, as indicated in Fig. 8.

When the nozzle N is arranged at an acute angle to the surface of a metallic body from which metal is to be removed, the inclination of the gas With this construction the oxidizing gas stream discharged from the passage 33 will strike the surface at a point closer to the discharge face 36 of the nozzle than the gas stream discharged from the passage 33. To permit the gas stream discharged from rectangular-shaped passage 33 to contact or strike the surface at the shortest possible distance ahead of the nozzle, the passage 39 is so formed that the side walls thereof converge, as indicated in Fig. 8. This produces a gas stream which flares sideways immediately after being discharged from the passage 39, so that it is effectively utilized to produce the portion ll of cut shown in Fig. 2, which portion preferablyshould have a sharp radius of curvature to obtain the surface contour desired in this particular in- In order that the nozzle can be positioned with its tip as close as possible to the surface of a metallic body, the discharge end thereof is tapered, as indicated at 4|. This permits the nozzle to be positioned a minimum distance from the metallic body and at the same time insures sufficient clearance as the nozzle is moved relatively to the surface.

In Figs. 9 to 13, inclusive, I have shown apparatus embodying the principles of my invention in which the nozzle shown in Figs. 6, 7, and 8 can be effectively employed to produce the surface contour illustrated in Fig. 2.

To move the nozzle N relatively to the edge surface of the plate It a self-propelled carriage (not shown) may be used. Such a carriage may be driven on the top surface of the plate 10 and guided by a rail mounted thereon. The carriage may have an arm secured thereto which extends beyond the edge of the plate, and on this arm may be mounted a downwardly extending bracket 50. as shown in Fig. 92 Apparatus of this character is described and claimed in J. H. Bucknam and A. J. Miller application, sci-m No. 1,470; filed January 12, 1935. Pivotally connected to the bracket at 5| is an angle member 52 to which in turn is pivotally secured at 53 a sleeve 54 that partially supports the apparatus, as will hereinafter be described. Since the pivotal connection at 5| permits angular adjustment in a vertical plane and the pivotal connection at 53 permits angular adjustment in a plane perpendicular to the vertical plane, the sleeve 54 can be adJusted in any desired position. To enable an operator quickly to position the sleeve 54 indicating scales 55 and 3B are provided at the pivotal connections 5! and 53, respectively.

In this apparatus the position of the sleeve 54 determines the exact angle at which the oxidizing gas streams discharged from the nozzle N are applied on the edge surface of the plate I0. It is desirable to maintain the nozzle N in its adjusted position during an entire metal removing operation and at the same time permit movement of the nozzle when irregularities in the edge surface are encountered. By permitting such movement of the nozzle, the tip thereof will always remain at the desired position to produce a uniform cut. This is accomplished by providing a flexible connection, such as the parallel linkage mechanism M, for partially supporting the nozzle N on a head 57 which is mounted on the sleeve 54.

To the outer end of the headbl is threadedly secured an adaptor connection 58 to which is iixedly connected a bracket 59. The parallel linkage mechanism MI comprises the fixed bracket 59, a movable bracket 60 to which the nozzle N is detachably secured, short links 6| pivotally connected at one end to the brackets 59 and 60, and links 62 pivotally connected to the free ends of the short links 6!. The pivotal connection of the short links 3| to the brackets 59 and 6!) permits horizontal movement of the end bracket 63 and nozzle N secured thereto, and the pivotal connection of the links 62 to. the short links BI permits movement of the bracket 50 and nozzle N in a plane transverse to or at right angles to the horizontal movement. The three parallel links 62 are thus universally pivoted at separate points to the supporting bracket 59 and to the nozzle holding bracket 60 and will therefore maintain the brackets substantially parallel to each other. With this arrangement the nozzle N will have vertical and horizontal movement and at the same time its angular position with respect to the plate ll will always remain constant. this position being determined by the setting of the sleeve 53 on the bracket 50. Qxidizing and combustible gas are delivered from the head 51- and adaptor connection 58 through flexible tubing 63 and 64, respectively, to the oxidizing and combustible gas passages 31 and 34 respectively in the nozzle N.

The nozzle N is also partially supported and guided along the edge of the plate In by a roller or guide 65 having its tread L-shaped with the vertical or flange portion 66 bearing against the edge of the plate and the horizontal portion 6! bearing on the top surface of the plate. At the the extreme edge of the plate, thereby insuring an accurate guiding of the nozzle N even when small projections occur at the extreme edge of the plate. The flange portion of the roller is inclined from the vertical plane in a direction toward the edge of the plate I 9 by inclining the axis of the roller at a relatively small angle to the plate surface, the tread. surfaces 66 and 81 being frusto-conical. With this arrangement the roller naturally tends to bear against the edge of. the plate as it moves relatively thereto, so as to maintain the tip of the nozzle N a constant distance from the edge surface.

The roller 65 is journaled at 68 to thelower end of avertical bracket 69 having at its upper end a sleeve 10 which is mounted on one arm of an angle member 1| and secured thereto by a set screw 12. This arrangement permits angular and axial adjustment of the bracket 69 on one arm of the angle member H. The otherarm of the angle member H extends through an opening in a block 13 and is keyed thereto at I4, as shown in Fig. 12, to permit only axial movement thereof. The angle member is maintained in its adjusted position by a set-screw 15.

The block 13 is loosely mounted on a shaft 16 and is secured thereto through resilient means comprising a torsion spring 11 disposed about a mandrel 18 keyed at 19 to the shaft 16. The mandrel bears against the block 13 and ismaintained in position by a set screw 80. The outer end of. the spring 11 is secured at 8| to the outer end of the mandrel", as shown in Fig. 10, and the inner end thereof is adapted to fit into any one of a plurality of openings formed in the side face of the block 13. The tension of the spring II can be readily fixed by changing the position of the inner end thereof, and such end can be secured to the block 13 by a set screw 82 adapted to fit into any one of a plurality of openings 83 formed on the peripheral surface of the block 13, which openings communicate with the openings formed in, the side face of the block 13.

A clamping block 84 is also loosely mounted on the shaft 16. The front portion of this block is bifurcated and provided with an opening to receive a threaded stud 85 to attach the block 84 to the top edge of'the bracket 69, as shown in Fig. 10. Angular movement 'of the block 84 with respect to the bracket 89 is prevented by a set screw 86 which extends through threaded openings in the bifurcated arms of the block 84.

A screw 81 for adjusting the elevation of the nozzle N extends through an opening in a projection 88 of the block 84, and the end thereof bears against an oif-set peripheral portion of a cam 89 fixedly secured to the shaft I8, as shown in Fig. 13. Upon moving the adjusting screw 81 no angular movement can be imparted to the block 84 and bracket '89 to 'which' the nozzle N is secured because, as mentioned above, the angular position of the nozzle Nwith respect to the plate I9 is dependent solely upon the'position of the sleeve 54. The elevation of the nozzle N can be adjusted, however, through the screw 81.

When the screw 81 is moved to the right, referring to Figs. 9, 10 and113, the cam 89 and shaft 16 are rotated clockwise. This clockwise movement'of the shaft 1.6 increases the angle of the angle member II with respect to the surface of the plate i0 and moves the roller 65 to the I member 93.

left. Since the bracket 59 is in a fixed position, the shaft Hi will be moved upward by the angular movement of the angle member II and horizontal movement of the roller 85. With such upward movement, the shaft 16 will raise the block 84, movable bracket 60, and the nozzle .39.

Conversely, when the screw 81 is moved to the left, the cam 89 and shaft I8 will rotate counterclockwise due to the'weight of the apparatus.

This counter-clockwise movement of the shaft 16 decreases the angle of the angle member H with respect to the surface of the plate I9 and moves the roller 65 to the right. Since the bracket 59 is in a fixed position, the shaft 18 will be moved downward by the angular movement of the angle member II and the horizontal movement of the roller 65. With such downward movement the shaft it will lower the block 84, movable bracket 69, and the nozzle N. To limit the counter-clockwise rotation of the shaft i6 and hence the lowest elevation of the nozzle N, the block 13 is provided with a projecting element 90, the end of which is disposed in the path of a projection 9i secured to the peripheral surface cf the cam 89, as shown in Figs. 12 and 13.

In a simpler form of apparatusrthe block 13 may be secured directly to the shaft IS. A resilient connection of the block 13 to the shaft biased in am; suitable manner to maintain the vertical portion 66 of the tread surface of the roller 65 bearing against the edge of the plate 7 l0. As shown in Figs. 9 and 11, downwardly extending flat members 92 and 93 may be journaled at substantially the opposite ends of the two links 62 in the same horizontal plane. A rod 94 extends freely through an opening in the member 98 and is secured at 95 to the member 92. The linkage mechanism M is urged toward the edge of the plate ill by a helical spring 96 disposed about the rod 94 and having the ends thereof bearing against the member 98 and a nut 91 on a threaded portion of the rod. The tension of the spring 96 can readily be adjusted by moving the nut 91 toward or away from the The operation of the apparatus illustrated in the drawings is substantially as follows: It will be assumed that the bracket 89 is positioned on the arm of the angle member 1| so that the tip of the nozzle N is a minimum distance from the edge of the plate III; that the angle member II is axially adjusted in the block 13; that the sleeve 54 is adjusted so that the nozzle N is positioned at the, desired angle inclined in the direction of advance of the metal removing operation with respect to the edge of the plate "I; that the nozzle N has been positioned at the desired elevation by turning the adjusting screw 81; and that the apparatus is positioned so that the nozzle N is adjacent one end of the plate I0.

With the above assumed conditions, the nozzle N is lowered so that the tip is opposite the bottom surface of the plate I 9. Thismay readily be accomplished by pushing down on the

blocks

13 and 84, the resilient connection of the block determined contour.

bustible gas the portion of the surface impinged by the flame is heated to an (elevated ignition temperature. The nozzle N may then be gradually raised by releasing the pressure on the

blocks

13 and 84. During this movement a narrow strip of the edge of the plate is heated sufflciently to have a wet surface film formed thereon.

when the nozzle N is at the initially adjusted position, oxidizing gas is supplied thereto through the tubing 63 and head-51 from a suitable source of supply. After a out has been started, the carriage (not shown) from which the bracket 50 depends, is propelled relatively to the horizontally disposed plate Ill, lengthwise of the edge to be flame machined. The oxidizing gas streams issuing from the

orifices

39 and 40 of the nozzle will then melt and oxidize the surface metal, and this oxidized and molten metal will be blown ahead of and sideways of the plate edge in a manner previously described, to produce the desired surface contour.

Since the movable parts of the apparatus including the bracket 60, block 84, angle member ii and guide 65 are biased toward the edge of the plate Ill by the spring 96, any irregularities in the surface of the edge will cause these movable parts to move horizontally; and this movement will cause the nozzle N to move a corresponding distance as it is moving with respect to the plate. Due to the parallel linkage M, however, which moves automatically in response to changes in the position of said guiding means, the nozzle will always remain in its adjusted position during the entire metal removing operation. Similarly, any irregularities in the top surface of the plate it will cause the bracket lid and other movable parts to move vertically and maintain the nozzle N at its adjusted position so that the uncut portion it will be of uniform height along the entire edge of the plate.

In view of the foregoing, it will be apparent that I have provided an improved apparatus for removing metal to produce a surface having a pre- Although the desired surface contour in most instances can be obtained in a single pass of the oxidizing gas streams, the desired surface contour may be produced by several passes of the oxidizing gas streams relatively to a metallic body.

The present apparatus for flame machining is particularly useful in preparing the edges of relatively thick metal plates for welding. The finished surface, flame machined as described, carries a very thin coating of iron oxides after the loose magnetic oxide has been removed from the surface. The thickness of this iron oxide film is substantially equal to a wave length of light, and beneath such oxide film there is a thin layer of metal containing carbon in an amount greater than that of the original metal before the flame machining operation. In this manner the flame machined surface is so conditioned and improved that subsequent welding of two plates having such surfaces is considerably facilitated, and the resulting welded joint has a strength and uniformity superior to joints heretofore produced in this field of welding.

While I have shown a particular embodiment of a nozzle and apparatus for carrying out my improved method, it will be apparent that modifications may be made, and certain features can be used independently of others without departing from the spirit and scope of my invention as set forth in the claims.

I claim: 1. Apparatus for removing metal from the surface of a body, comprising the combination of means disposed adjacent said surface for applying at least one oxidizing gas stream thereon;

supporting means; means for flexibly connecting 2. Apparatus for removing metal from a substantially vertical surface of a body, comprising the combination of means disposed adjacent said surface for applying at least one oxidizing gas stream thereon; supporting means; means for flexibly connecting said oxidizing gas stream applying means to said supporting means for partly supporting said applying means and for permitting movement thereof; means adapted to bear against said surface and movable relatively thereto for guiding said applying means; means resiliently connecting said guiding means to said gas stream applying means whereby said applying means may be moved relatively to said guiding means transversely of said surface; means cooperating with said flexible connecting means for urging said guiding means against said surface; and means for relatively moving said oxidizing gas stream applying means and said body lengthwise of said surface.

3. Apparatus for removing metal from a substantially vertical surface of a body, comprising the combination of means including a nozzle adapted to be disposed adjacent saidsurface and inclined at an angle thereto for applying at least one oxidizing gas stream thereon; means adapted to contact said vertical surface and the top surface of said body for partly supporting said nozzle and for guiding the same to maintain the tip thereof a substantially constant distance from said vertical surface as it is moved relatively thereto; supporting means; means flexibly connecting said nozzle to said supporting means for partly supporting said nozzle and for permitting vertical and horizontal movement thereof automatically in response to changes in the position of said guiding means, said flexible connecting means being so constructed and arranged that said nozzle will always maintain the same angular position with respect to said vertical surface irrespective of any movement thereof; means cooperating with said flexible connecting means for urging said nozzle and said guiding means toward said vertical surface; and means for rela-, tively moving said nozzle and said body.

4. Apparatus for removing, metal from a substantially vertical surface of a body, comprising the combination of means including a nozzle adapted to be disposed adjacent said surface for applying at least one oxidizing gas stream thereon; means resiliently connected to said nozzle and adapted to contact said vertical surface and the top surface of said body for partly supporting said nozzle and for guiding the same to maintain the tip thereof a substantially constant distance from said vertical surface as it is moved said nozzle is disposed at an angle to said ver-,

. tical surface, and in which said flexible connecting means is so constructed and arranged that said nozzle will always maintain the same angular position with respect to said vertical surface irrespective of any movement thereof, the angular position of said nozzle with respect to said surface being dependent upon the adjusted position of said member mounted on said supporting means; and position indicating means associated with said member and said supporting means.

6. In apparatus for removing metal from an edge surface of a metallic body supported in a substantially horizontal position, the combination of means including a nozzle adapted to be disposed adjacent said edge surface for applying at least one oxidizing gas stream thereon; means adapted to contact said edge surface and the top surface of said body for supporting said nozzle and for guiding the same to maintain the tip thereof a substantially constant distance from said edge surface as said nozzle is moved relatively thereto; and means resiliently connecting said supporting and guiding means to said oxidizing gas stream applying means whereby said applying means may be moved relatively to said supporting and guiding means transversely of said edge surface.

7. Apparatus for removing metal from a substantially vertical surface of a body comprising the combination of means including a nozzle adapted to be disposed adjacent to said surface for applying at least one oxidizing gas stream thereon; means connected to said nozzle and adapted to contact said vertical surface and the top surface of said body for partly supporting said nozzle and for guiding the same to maintain the tip thereof a substantially constant distance from said vertical surface as it is moved relatively thereto; supporting means; a member mounted on said supporting means and adjust able thereon; means flexibly connecting said nozzle to said member for partly supporting said nozzle and for permitting vertical and horizontal movement thereof; and means for relatively moving said nozzle and said body.

8. Apparatus according to claim 7 in which said nozzle is disposed at an angle to said vertical surface; and in which said flexible connecting means is so constructed and arranged that said'nozzle will always maintain. the same angular position with respect to said vertical surface irrespective of any movement thereof, and said member mounted on said supporting means is adjustable to have any of a plurality of predetermined angular positions whereby the angular position of said nozzle with respect to said surface is determinedby the adjusted position of said member mounted on said supporting means.

9. Apparatus for removing metal from the surface of a body, comprising the combination of nozzle means for applying at least one oxidizing gas stream. against said surface; means associated with said nozzle means adapted to engage said surface 'for. guiding said nozzle means to maintain the discharge end thereof a substantially constant distance from said surface as it is moved relatively therealong; supporting means; means for effecting relative movement between said supporting means and said surface; and mechanism movably connecting said nozzle means to said supporting means for providing movement of said nozzle means toward or away from said surface, said mechanism comprising three parallel links having end portions pivotally connected at three separate points to said supporting means and their other end portions pivotally connected at three separate points to said nozzle means.

10. Blowpipe apparatus comprising the combination of nozzle means for applying at least one gas stream against the surface of a metal body; means associated with said nozzle means adapted to engage said surface for guiding said nozzle means to maintain the discharge end thereof a substantially constant distance from said surface as it is moved relatively therealong; supporting means; means for effecting relative movement between said supporting means and said surface; and mechanism movably connecting said nozzle means to said supporting means for providing both vertical and horizontal movement of said nozzle means, said mechanism comprising a plurality of parallel links, each of said links having one end portion universally pivoted to said supporting means and its other end portion universally pivoted to said nozzle means, the pivotal connections being at spaced apart portions of said supporting means and at spaced apart portions of said nozzle means.

ll; In a blowpipe apparatus for applying gas against a surface of a metal body adjacent an said nozzle means to maintain the tip thereof a substantially constant distance from said adjacent surface of said body and the zone of application of said gas stream at a substantially constant distance from said edge corner during relative movement between said body and said nozzle means along and parallel to said edge corner; said roller having its axis of rotation inclined toward said corner at a relatively small angle to one of said surfaces, said roller having tread surfaces angularly related to each other and to said axis, and an annular recess between said tread surfaces for preventing contact of said roller with said edge corner whereby said nozzle means is guided solely by said surfaces forming the edge corner.

HERBERT E. SERNER.