US1040569A - Method of making seamless tubes. - Google Patents

Description

uw. OEFUTT. METHOD OF MAKING SEAMLESS 'l'UES Patented Oct. 8, 1912 l2 8HEETS-SHEET 1.

FIG.5

mvg-mon SEAMLESS TUBES,

APPLIUATION FILED SI1T.2B,1910.

0A w T E E H u... S T E E H qu 2 Patented Oct. 8,

s L 5 E. N w.. W

over a plug.

.ing operations.

VUNITED s Arias PATENT oFFIon.

JOHN W. OFFUTT, OF ELLWOOD CITY,\1ENNSYLVANIA, .ASSIGNOR TO THE SHELBY STEEL TUBEV COMPANY, OF PITTSBURGH, .PIINNSYLTANIILI A CORPORATION OF New .mn/snr. y

Specication of Letters Patent.

Patented oet. 8,1912.

Applicationled September 28, 1910. Serial `;t\To...54,339.

To all @ahem fit may concern Be it known that I, JOHN W. vOrrufrr, of `Ellwood City, .in the county of 'Lawrence and State of Pennsylvania, have invented a 5 new and useful Method of Making Seamless Tubes, of which the following is -a full, clear, and exact description, reference being had to the accompanying drawings, .forming part of this specification. 5

My 'nvention relatcsto the 'manufacture of seamless tubes and more particularly relates to the manufacture ofhot finlshed tubes not necessarily requiring furthercold' rolling or drawing operations' to complete 15 the tubes.

Heretoforc, in making sea-lnlesstubes, ,the billets after being pierced are lessened in diameter and wall-thickness in the passes of a rolling mill by reducing the pierced billets. In `the piercing operation and in reducing the billets by rolling over thel plugs, which are held stationary 1n position in the passes formed between the rolls ofi the rolling mill by means ofsuitfable.rodsI or` |25 mandrels, the surface of the pierced :billet or tube -is rough and irregular, thevinner sur-- face of the hollow tube being scratched and roughened to such an extent that the product is not salable until after furtherdinish- Owing to the construction of the reeling rolls employed in carrying out the reeling operations, theA4 tube is rotated` about its longitudinal axis by the reeling operation. l'n the reclingmechanism shown,

3.5 While the reeling rolls and the frame in which the-reeling rolls are supported rotate around the longitudinal axis of the tube, the frictional resistance of the roll bearings and of the contacting surfaces of the rolls and 40 the tub'e causes the tube and its mandrel to` rotate withthe -frame of the reeling mecha-1 l I,nism unless lmeans `are provided for holding.

and preventing such rotation of the tube and 'the .surface `defeat-te in the rolled tubes are .not removed 1b `the action of the reeling.y

I rolls. :In additionito these defects,- the .tubes are notgformed true to ga e or wall thickness, nor `are they of the l esired .round or circular .cross section, a cold drawing op 'eratio ',.heing necessary to yfinish such .tubes .One object of my invention is to provide `anILilutifofoyed .method of making seamless 'tubes mj which the..pierccd tubes are aptomaltlcallydicld and;

l prevented from-rota ing ahoutftheirlougitudinal.axisv during the 'suct cessive forming operations, and surface detects removed fronrthc tubesthereby.

Another object of the inventionis to provide an improved'method of making seamless tubes in whichdefects upon the inner and outer surfaces of the tubesare eliminated and by which 'the'tubes are'completed to gage or wall Athickness and circular in cross section without cold drawing.

A further object-,of this invention is to provide an yimproved method of making such .tubes by which tubes of the desired size and gage are'produced without grooves or scratches orother surface defects hereto- 'fore present in tubes as made by existing methods and a hot finished seamless tube is made which is round or cylindrical and which does not necessarily require further cold drawing operations i-n order to be a marketable product.

A still `further object of my invention is to .provide ,a method of making seamless tubes in which heated, pierced billets are placed upon a mandrel and are then sub jected, in a series of continuous steps, to rolling, reeling and sizing operations nrranged 'to `permit of the -easy withdrawal of the mandrel after `the sizing operations and to provide a method of forming suchtubes permitting the use of a-mandrel shorter than the finished tube.

InIthe accompanying drawings, 'Figure 1 is a sectional plan showing fthe preferred ronstruction and `arrangementof apparatus for use in carrying out my improved method offorming-pierced billets into tubes. Fig. 2 is a diagrammatic `plan showing another arrangement of apparatus constructed and adapted for use 1n carrying out my improved method. Fig. 3 1s asectional side elevation of the rollingmill and the reeling rolls forming part of theapparatus shown in .Fig 2. Pig. 4 is a detail longitudinal section showing, on `a larger scale, the reel. ino' mechanism of Figs. 1 and 2. .Fig. 5 `is a longitudinal plan, the billet- ,being shown in longitudinal section, showingthe pierced billet or,partly Aformed tube in position on thermandrel as arranged during the rolling and.rceling operations forming part of this..

furnace `in whiclhthe billets or blanks are heated, and B, 3, are the uolls of' a piercing mill .which is located conveniently 1n front -110 "be heated to the desired temperature. The

' pierced or hole in the pierced billet A, as shown in.

, 10', 10g, of the continuous rolling mill l heated billets are successively removed from the furnace and are subjected to a piercing operation between the rolls` 3, 3.- ot` the piere- Iing mill,- the plug 4 being held in position between the rolls `during the piercing operation by the rod or mandrel 5. The billets are caused to travel lengthwise during the piercing operation by rthe action of, the piercing rolls 3, 3, and finally are delivered upon the eonveyer (i. The rod or mandrel is then removed trom the pierced billet, the plug 4 having` become detached from the end of this rod or mandrel 5 at the comple` tion of the piercing operation, andA the billet, after the bar 5 is removed, is delivered sidewise across the ways or skids 7 to the conveyer 8. A cylindrical mandrel 9, preferably oit greater length than the iinished tube is then'placed within the opening Fig. 5. The billet A on its mandrel is then .fed forwardly between the `first`set of rolls 10 of the rolling mill and passes between the rolls ot the successive stands of horizon ta'l and vertical rolls, 10, 10",' 10c, 10d, 10,

shown.

A. in which the tube is slightly In the iirst stand ot rolls 10 the billet is forced tightly around the cylindrical mandrel 9 and is reduced. somewhat in cross sectional area, and, in the later stands of rolls, the thickness of the wall and `cross sectional area of the pierced billet or partly finished tube A is further reduced and the tube. elongated. Ihevrollech partly formed tube, together with its mandrel is then delivered forwardly' into the bite ot the reeling rolls 11, reduced in wall thickness by the action. of the reeling rolls and is made truly cylindrical giving the tube a yfinished surface. flhe tube which has been pressed tightly into very close contact upon the mandrel i) by the action of v the-.rolls of the rolling mill, is increased inV bore and the mandrel is loosened by this reeling operation sutiiciently to permit of its easy removal after the reeling'operation is completed. l

As shown in Fig. 2, the tube and its mani ,di-el are delivered from the reeling rolls 11 upon the conveyor 13 and are then transt'erred sidewise upon the skids or ways llt to the conveyer 15. T he mandrel 9 is then extracted from the rolled and recled tube,- power being applied when necessary by means ot' the mechanism o the extractor bench 16, to e'l'ect'the removal of the Inandrel and the tube is delivered lengthwise be` tweenl the rolls of the sizing apparatin formed as shown by the horizontal rolls '12 and vertical rolls 12", and is formed to the desired. diameten The siz'ed tubes are then delivered lengthwise by the conveyer 15 into the cross rolls 17 by which they' are straightened and completed, and the finished tubes are then delivered upon the conveyer 18 leading from the cross rolls to a cooling bed orother place-of disposal.

1n using apparatus like that shown iu- Fig. ito carry out my improved method, the pierced billets A after beingplaced on a mandrel, are introduced into the rolls of the rolling mill as before described. The wall thickness eda the tubeis reduced in the sue- .cessive passes `formed b these rolls and the tube is delivered there romnto ythe reeling rolls. In this case the reeling rolls and the "frame onwhich the rolls aremounted are constructed as shown in detail in Fig.4,anrl the frame and rolls are rotated about the longitudinal axis of the blank and mandrel 'in the saine mannen as shown .infFigs 9 and 3. The rolled and reeled blank upon emerging from the reeling'rolls entersthe sizing rolls. and a port-ion of the blank is sized while the mandrel is still within the blank. The blank then passes to the mandrel extractor bench where the mandrel is removed Vfrom the sized tube.

`The reeling,r operation slightly increases the diameter of the opening or holevin thel tube and loosens the tube which has been tightly rolled upon the mandrel by the rolling operation. While the passes in the sizing rolls slightly reduce thediameter of the tubes, these passes are so proportioned that the tube, although reduced in diameter in being sized, is not reduced sulliciently to be again closed tightly aiound the mandrel within the tube. The sized tube, after the mandi-el is removed, then passes forwardly trom the sizing rolls to cross rolls, in which it is straightened in the saine manner as shown in Fig. 2 before described. The s'o finished tubes, after being cut to lengt-h, are in readiness for shipinentiinless itis desired to further reduce the tubes by a cold draw ing process. Should suclncold drawing step be necessary, the hot finished tubes are then pickled sind are cold drawn on drawing benches, 'in the usual manner, which not forming part of my improved method need not be lfurther describe( When a mandrel shorter than the finishedtube is employed, instead of one which is .ot

greater length than'that of the finished tube, portions of the tube will have a, lon itudinal movement `relative to the mandrel during the rolling and reelingr operations.

The 'iuli'antages of my invention will be apparent to those skilledin the art.

By using my improved method a hot iam;

4pierced eine@ 01 nwe is enigmi n a Single heels and in a,Y series of continuons related steps Into u nislieclseeniless tube.

Modifications 1n' the cenetruetion end en l. rangement of the :q )pmatus foi' carrying out .im wing i he apmy method muy be made with from myY invention Aas defim` 'ended claims. -l`While preferehlT 'ie11`,bbviously pierced billets may be healed the heet-K l .1l-:Ll: blanks are pier'ced und hen @rushed et. eleiinitlel heet, prier to the piercing @perve- Lemme the steps eonsisting in subjecting a heated tubular blank while on 4:i mandrel succesi sively and simultaneously-to the action'of thesolls of rolling mill, a reeling machine and ef sizing rolls to thereby form the tubes in a, manner a'ordng e continuous'opera.- tion.

3. 1n thennannfeture ofseizinless ltubes,

the steps consisting in subjecting eheated tubular blank ywhile on a mandrel successively to the action o the rolls of a'ji-olling mill, e reeling machine and of sizingblls,

lhe aelzion of the reeling and of fthe .Sizing rollsV being simultaneous to-thereby form the ,tubes 1n a" manner aerdmg a continuous operation.

.ln testimony whereof, I have hereunto set my hand.

l JQHNWUEFUW *Witnesses/I l Y flBRowN, Y

Leggere H. llllfmn.

ce y

Images