US1732912A - Method of removing defects from steel billets - Google Patents

Description

Oct. 22, 1929. R; E, JR 1,732,912

METHOD OF REMOVING DEFECTS FROM'STEEL BILLETS Filed June 2. 1928 A TTORNEY Patented Oct. 22, 1929 UNITED STATES;

PATENT OFFICE v ROBERT M. ROOKE, JR.. OF JERSEY CITY, NEW JERSEY, ASSIGNOR TO AIR REDUCTION COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK METHOD on nEMovme narrows anon STEEL 3mm Application filed June 2, 1928. Serial No. 282.291.

' ated in rolling or forging as'flaws in the final product.

These defects are in thenature of cracks,

fissures or seams extending inward from or I below the surface. In the original billets. or in the material after rolling or forging. they are variously known as seams, cracks, hair cracks. hair seams, lap seams. laps, cold laps,

. cold shuts, and snakes, a snake being a long wavy seam often found in billets. Seam may be used as a general term.

The usual practice is to gouge out the seam or defect with a pneumatic hammer and chisel. This has the disadvantage of being slow, and while it may be successful, it is difficult to see whether or not the channel is made to the bottom of the crack. as the chisel has a tendency to cover up the defect. Moreover, the chiseling operation being laborious, the gouge may not be made wide enough, and if too narrow it will be closed in by subsequent rolling or working, with the result that the defect will not be eliminated in the final product.

According to the present invention the defects are gouged outby burning the metal away in anoxygen stream scooping crosswise of the defect. In this way the gouge may be made of any width and ofs'uflieient depth with equal ease, and the defect appears to be opened up and magnified, whereas when the chisel method is used it is often difficult 'to determine whether all thedefect has been re moved.

Furthermore, the present method has a great advantage in speed, thereby increasing the output and reducing the laborcost. In some mills it is costing $14.00 to $16.00 a ton for chipping billets, which means about- 1 per pound on the finished product. By the present method this expense is greatly reduced.

- In the accompanying drawings forming part hereof:

Fig. 1 is'a perspectiveview illustrating the manner of removing a defectin a billet' by means of the invention; 4 A

Fig. 2 is an end viewof the same;

Fig. 3 is a schematic view representin a portion of an end or cross-section of a billet, showing in the middle a seam, at the left a properly made gouge which has removed a. defect, and at the right a gouge which has seemingly removed a defect but is too narrow;

Fig. 4 is a similar view of the same illustrating the effect of rolling; and

Fig. 5 is a schematic view of a portion of a' billet indicating the result that would be obtained with an ordinar Y oxygen cutting jet if the attempt" were ma e to remove a defect therewith.

Fig. 1- illustrates a billet 2 having a seam or snake 3 in one.surface.- A wide, shallow depression including the place where the seam was has been gouged out by an oxygen stream, aided as a practical matter b heating jets, delivered from an oxyacety ene or like torch 4. A portion of the seam has been removed.-

downwarchand then, as its velocity fails and a r as it is consumed, is deflected upward again, so as to burnthe metal and blow out the oxide,

forming the broad curved depression 6. The

" torch held in the same manner, the kerf 27 not only not removing the seam but constituting another defect.

At the left of Fig. 3 there is shown a properly formedgouge. and at the right a gouge that is too narrow. Fig. 4 shows that, after rolling, the seam 3 is still present and isbecoming a concealed flaw, and that whereas the properly formed gouge is being flattened out. the narrow gouge is being closed in.

The drawing indicates the head 7 and the forward portions of the pipes 8, 9 and 10 of" would occur if the regua cutting torch,

the oxygen for combustion with the metal,

- the pipe 9 the oxygen for the heating jets, and

the pipe 10 the acetylene or other combustible gas for the heating jets. The method can be performed with an ordinary cutting tip by throttling down the oxygen sufliciently to se- 7 cure the requisite low outflow velocity from v out deflection,

the'cutting jet orifice, or the torch or tip 'used may be specially designed to deliver a low veloclty stream of suitable size.

In operating on billets or the like to remove defects by this process, the seam is entirely visible at all times while the work is under way, and the operator can easily regulate the depth and width of the channel so as to remove the seam entirely and leave the billet in proper condition for rolling. The tip ma be inclined slightly forward, as Well as laterally of the scam, the particular angle of the tip and the inclination of the side of the gouge being readily determinable by the operator taking into account the speed of cutting, the gas and oxygen pressures, and the shape of the channel to be made.

While the term cutting has been used, it will be understood that the action that takes place is similar to cutting only in that there is a 4 true combustion of the metal with the oxygen. Otherwise, the/process is carried out in a manner entirely different from regular cutting, wherein a high velocity jet acts withand, for the cutting of kerfs through metal, the action is confined as narrowly as possible between parallel planes.

Instead of acetylene, any other suitable combustible gas may be used for the heating jets.

lclaim: p

The herein described method of preparing defective billets or the like for rolling or forging, which comprises gouging out the surface portion of the billet containing a seam or other defect by combustion with a stream of oxygen of suitable velocity directed at an inclination to the surface of the metal and crosswise with respect to the direction of displacement of the stream.

' ROBERT M. RDOKE, JR. 1

the pipe 8 serving to conduct

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