US817796A - Apparatus for cross-rolling tubular bodies or blanks. - Google Patents

Apparatus for cross-rolling tubular bodies or blanks. Download PDF

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US817796A
US817796A US20107804A US1904201078A US817796A US 817796 A US817796 A US 817796A US 20107804 A US20107804 A US 20107804A US 1904201078 A US1904201078 A US 1904201078A US 817796 A US817796 A US 817796A
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plug
rolling
blanks
mandrel
cross
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US20107804A
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John H Nicholson
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National Tube Co
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National Tube Co
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B19/00Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work
    • B21B19/02Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work the axes of the rollers being arranged essentially diagonally to the axis of the work, e.g. "cross" tube-rolling ; Diescher mills, Stiefel disc piercers or Stiefel rotary piercers
    • B21B19/04Rolling basic material of solid, i.e. non-hollow, structure; Piercing, e.g. rotary piercing mills

Definitions

  • the piercing-point is a conical-shaped mandrel which has an uninterrupted continuous conical surface that acts as an anvil over which the biilet is advanced,
  • Fig. 1 is a Fig.
  • Fig. 3 is a view similar to 2, showing another form 'f of the invention.
  • Fig 4 shows a special alpphcation of the invention to reducing t e wall thickness without enlarging the dlameter of the tube.
  • B, C, and D are three plugs or mandre s independently rotatable and coaxiallymounted one in front of the other upon a mandrel-bar F.
  • G and H are rolls,
  • I qual rolls having a plurality of conical or conoidal surfaces that cooperatewith the plugs B C, and D.
  • J and K are guides which, as shown, snugly surround and guide the blank or tube L all points except Where the rolls G and H act upon it. It Wlll be notice'din Fig.1 that the tubular body L, aswell understood, will be slightly elliptical in form, while under the action of the rolls G .and H of course the guides J and K must conform and allow for at substantially,
  • diverging portions 11 and the piercing or expending mandrel B first give the rolling, compressing, and feeding of the metal onto the point of the plug B and thenv the expansion and reduction of the wall thickness upon the lar er base portions of the plug B.
  • Fig. 1 provision is found for thinning the wall of the tube without at the same time enlarging it too much.
  • the rolling-surfaces 12 compress and reduce the tube exteriorly without any interior support from the C at a-somew at smaller diameter than the largest part of lug B.
  • the rolling-surfaces 13 diverge, and consequently com ress, expand, and reduce the thickness 0 the tube upon the plu 0.
  • Plug 0 therefore repeats an efiect simi ar to that of the base portion of plugB.
  • plug D is a cylindrical smoothing-plug, which 006 erates with the rolling-surfaces 14'of the r'ol s, which form between them a parallel and not a diverging portion of the pass.
  • the interval between the plug D and the rolling-surfaces 14 should converge slightly, too slightly to be noticed in the drawings, so as to merely smooth out the irregularities on the interior and exterior of the tubular wall without materially expending or materially confining the wall.
  • the exte-' rior rolling-surfaces therefore have a pro-
  • Plug B has a rear-extending center or trunnion 17, which fits a recess in the plug G and permits the point of plu B-to turn relatively to the plug C.
  • a was er 18 is interposed between them.
  • the washers 18 may e of diderent thicknesses to nicely adjust the position of plug B longitudinally; but in addltion to ermitting adjustment these washers are 0 great importance as compensating for the wear, which is very much greater u on the plugs B and C than upon the plug Owing to the increased eripheral speed of the larger diameters of t e rollers G and H and a consequent increased speed effect due to the skew of the roll, there is a tendency for the heated metal which is being rolled to travel more rapidly between the plug D and the surfaces 14 than between the plug B and the surfaces 11 and 10.
  • the rolling-tubes are in the form of disks and N.
  • the plugs B, C, and D are substantially the same as in Fig. 1.
  • Several adjustment-washers 16 and 18 are shown, and the exterior rolling-surfaces of the rolls or disks M and N are also shown adjustable by means of the removable rings 20 and 21 secured by adjustable bolts 22 and backed by washers 23 and 24.
  • This construction is valuable not only as permitting adjustment, if necessary, of the width of the pass, but more particularly as permitting the com ensation for the wearin away of the rol in surfaces.
  • As the s aces wear away add itional annular washers 23 and 24 may be inserted or thicker ones substituted for those already in place.
  • Fi 3 differs in principle from Figs. 1 and 2 on y in the omission of the intermediate lug C. This figure therefore provides only or the initial action upon the p ug B and the smoothing and finishing action .upon the phig D.
  • ro mechanismcom rising apiercing lug or mandrel means f dr forcing the bl nk on said piercing-plug, diverging rollwalls for e anding, elongating and simultaneously riiducing the thickness of the blank on said plug, converging roll-Walls for externally compressing the blank, asecond plug or mandrel rotatable independently of sai against said first-named plug,
  • first-named plug roll-walls for again expanding, elo ating and reducing the thickness of the bla u on said second-named plug, an independent y-rotatable smoothing-mandrel, and roll-walls for compressing and smoothing the tube on said smoothing-mandrel.
  • rolihng mechanism com a piercg lug or mandrel, means or forcing the bla on said piercing-plug, diverging rollwalls for e an elongating and simultaneously re ucing the thickness of the blank on said plug, conver roll-Walls for externally compressing the lank, an independently-rotatable smoothing-mandrel, and rollwalls for compressing and smoothing the tube on said smoothing-mandrel.
  • ro gmechanism com rising apiercingnilug or mandrel, means f dr forcing the bla on said piercing-plug, diverging roll- Walls for expanding, elo ating and simultaneously reducing the thil mess of the blank on said lug, a second plu or mandrel rotatable in ependently of sai first-named plug, and roll-walls for a ain expanding, elongating and reducing the t 'ckness of the plug upon said second-named plug.
  • rolhng mechanism com rislng a piercing plug or mandrel, means or forcing the blank on said piercing-plug, diverging rollwalls for expanding, elon ating and simultaneously reducing the thic ess of the blank on said plug, converging roll-walls for externally compressing the blank, a second plu or mandrel rotatable independently of said first-named plug, and roll-walls for againexpending, elon ating and reducing the thickniess of the b ank upon said second-named u p 7%
  • a aratus for cross-rolling tubular bodies or l i l anks in a heated state the combination of a lurality of exterior rolling bodies, a plurahty of independently-rotatable interior bodies, said exterior and interior bodies constituting means for rolling and reducing the heated metal in a single pass upon the interior bodies in succession, and between
  • apparatus for cross-rolling tubular bodies or blanks in a heated state the combination of means for simultaneously expanding and reducing the thickness of the heated metal between interior and exterior expanding-surfaces, a cylindrical interior supportingbody, rotatable independently of said interior expanding-surface, and means for subsequetly compressing and smoothing the metal inside and out upon said substantially cylindrical interior supporting-body in the same pass, for substantially the purposes set forth.
  • a rolling mill having a plurality of rolls forming a pass, a plurality of mandrels supported in succession in the said pass, and means for adjusting one portion of the active rolling-surface of one of the rolls relatively to the other ortions, for substantially the purposes set orth.
  • rolhng mechanism comprising a piercmg In or mandrel, conve g roll-Walls for orclng the blank on sai rercing-plug, diverging roll-walls for expan g, elon ating and simultaneously reducing the thickness of the blank on said plug, converging roll -walls for externally compressing the blank, an independently-rotatable smoothing mandrel, and roll-walls for compressing and smoothing the tube on said smoothingmandrel.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Metal Rolling (AREA)

Description

No. 817,796. PATENTED APR. 1'7, 1906.
J. H. NICHOLSON.
APPARATUS FOR GROSS ROLLING TUBULAR BOfiIES OR BLANK. APPLICATION FILED APR. 1, 1904.
3 SHEETS-SHEET 1.
awuv/wtoz 5 0 9 1 7 1 P P A D E T N E T A P APPARATUS FOR GROSS ROLLING TUBULAR BODIES 0R BLANKS.
APPLICATION FILED APR.1. 1904.
3 SHEETS-SHEET 2.
No. 817,796. PATENTED APR.17', 1906. J. H. NICHOLSON.
- APPARATUS FOR (moss ROLLING TUBULAR BODIES OR BLANKS.
AAAAAAAAAAAAAA AA PR. 1, 1904.
cold-drawn to a finish with nnrrnn srnrns ngrrnnr omen.
JOHN H. NICHOLSON, OF PITTSBURG,-PENNSYLVANIA, ASSIGNOB. TO
NATIONAL TUBE COMPANY, OF NEW OF NEW JERSEY.
YORK, N. Y., A CORPORATION I APPARATUS FOR CROSS-ROLLING TUBULAR BODIES 0R BLANKS.
Specification of Letters Patent.
Patented A ril 17, less.
Application filed April 1,1904. Serial No. 201,078.
To all whom it may concern:
Be it known that 1, JOHN H. NICHOLSON, third vice-president of the Shelb Steel Tube Company, a citizen of the Unite States, and a resident of Pittsburg, Pennsylvania, have invented certain-new and useful Improvements in Apparatus for Cross-Rolling Tubular Bodies or Blanks in a Heated State, of which the following is a specification accompanied by drawings.
The cross-rolling process as invented by the Mannesmanns and improved by Ralp Charles Stiefel and others, while satisfactory under certain conditions, has 'ven considerable trouble where it is desire to make small tubes with thin smooth walls in a single piece without undue strains upon the' metal. In these processes the piercing-point is a conical-shaped mandrel which has an uninterrupted continuous conical surface that acts as an anvil over which the biilet is advanced,
the revolving rolls rotating the billet, im-
in the metal, and reduc the thickhes iif the wall of the formin iube. This 0 eration produces a hollow b ank or tube, t e thickness of the wall being dependent upon the size of the piercing-mandrel and the opening or pass between the rolls, Vandit is a general law in iercing with these t es of machines that t e thinner the wall the arger the diameter of the tube and the more severe the stress or strains put upon the physical conditions of the metal.
It is the prime object of the present im-' provement to divide or split u the rolling operation into a number of di erent steps or suboperations (but all being performed simultaneously on the sanebmazhine) }tor the ose of im re an ett r' t e coni t i ns under whib h the walls ar lecreased 'in thickness and whereby the lineal length of cross-section 'on the lane 1 of Fig. 1. '2 is a similar view ot a modification, part of an of the standard lengths required for pipe or oiler tubes.
These and certain other aims and advan tages will readily be apparent to those skilled in the art; and the invention consists of apparatus for carrying out the above objects embodying the features of construction, combinations of elements, and arrangement of parts having the eneral mode of o eration substantiall as hereinafter fully described and claims in-this s ecificationand shown in the accompanying rawings, in which' Figure .1 1s a die ammatic illustration,
partly in longitudina section through a ass,
sho
the rolls and plugs or mandre s in full an the metal in section. Fig. 1 is a Fig.
one roll being shown in section. Fig. 3 is a view similar to 2, showing another form 'f of the invention. Fig 4 shows a special alpphcation of the invention to reducing t e wall thickness without enlarging the dlameter of the tube.
In Fi. 1, B, C, and D are three plugs or mandre s independently rotatable and coaxiallymounted one in front of the other upon a mandrel-bar F. G and H are rolls,
preferably I qual rolls, having a plurality of conical or conoidal surfaces that cooperatewith the plugs B C, and D. J and K are guides which, as shown, snugly surround and guide the blank or tube L all points except Where the rolls G and H act upon it. It Wlll be notice'din Fig.1 that the tubular body L, aswell understood, will be slightly elliptical in form, while under the action of the rolls G .and H of course the guides J and K must conform and allow for at substantially,
this ellipticity and longitudinally should be plfofiled in the same way as the rolls are proed to form the ass. The rolls, as welliu'n-,
derstood, are pre erably skewed to produce a Y feeding efl ect, though some parts of the process and some advanta' es may be derived without skewing the rcfils, the metal being forced throu h by a ram; but the 'feedin elongatin e if ,a rameed only is rovided. The X0llSG and H have rolling-s g andof the pass, which in cooperation with the.
ect of the rolls will be sacrificed aces 10,11, 12, 13, and 14. Surfaces 10 form a converging portion.
diverging portions 11 and the piercing or expending mandrel B first give the rolling, compressing, and feeding of the metal onto the point of the plug B and thenv the expansion and reduction of the wall thickness upon the lar er base portions of the plug B.
n Fig. 1 provision is found for thinning the wall of the tube without at the same time enlarging it too much. Thus the rolling-surfaces 12 compress and reduce the tube exteriorly without any interior support from the C at a-somew at smaller diameter than the largest part of lug B. The rolling-surfaces 13 diverge, and consequently com ress, expand, and reduce the thickness 0 the tube upon the plu 0. Plug 0 therefore repeats an efiect simi ar to that of the base portion of plugB. Finally plug D is a cylindrical smoothing-plug, which 006 erates with the rolling-surfaces 14'of the r'ol s, which form between them a parallel and not a diverging portion of the pass. The interval between the plug D and the rolling-surfaces 14 should converge slightly, too slightly to be noticed in the drawings, so as to merely smooth out the irregularities on the interior and exterior of the tubular wall without materially expending or materially confining the wall. lugs C, and Dcooperate with progressively-increasing diameters of the exterior rollmgurfaces, the mean diameter of the surfaces 13 being greater than of surfaces 11 and the mean diameter of surfaces 14 being greater than that of surfaces 13. The exte-' rior rolling-surfaces therefore have a pro-,
essively-increasing peripheral s eed from out to rear ofthe pass, and the ugs B C D in order to have roper speed re ations with the external .bo es must be free to rotate relatively to each other. This is accomlished-by mountin the plug D so that it is cc to upon t e rejecting end of the mandrel-bar? (seenin ottedlines within it.) The plug C is 'rewise mounted so as to turn freely upon the end of the mandrel-bar, and one or more washers 16 are preferably interposed between 'C and D to take the end thrust. f Plug B has a rear-extending center or trunnion 17, which fits a recess in the plug G and permits the point of plu B-to turn relatively to the plug C. A was er 18 is interposed between them. By increasing or decreasing the thickness of washers 16 the plug 0 may be adjusted longitudinally, and thereby'the space between the plug C and the rolling-surfaces 13 may be adjusted with great nicety. Similarly, the washers 18 may e of diderent thicknesses to nicely adjust the position of plug B longitudinally; but in addltion to ermitting adjustment these washers are 0 great importance as compensating for the wear, which is very much greater u on the plugs B and C than upon the plug Owing to the increased eripheral speed of the larger diameters of t e rollers G and H and a consequent increased speed effect due to the skew of the roll, there is a tendency for the heated metal which is being rolled to travel more rapidly between the plug D and the surfaces 14 than between the plug B and the surfaces 11 and 10. This seems to produce an elongated or tensile ef fect upon the metal in the pass, and it seems to go through the pass with less expenditure of mechanical energy than would otherwise be the case, while, furthermore, the independent freedom to rotate of the successive plugs B C D contribute to this advantageous effect and not only reduces the power required, but also greatly lessens stresses and strains to which'the metal is subjected. It is 'possible by this process and by means of this a paratus to roll a tube with a thin smoot wall without an undue strains in the metal and to acromp ish this at a single pass, so that the tube is ready for finishing on a cold-bench without the subsequent usual rollin operation. From a given size of bil let or lank it seems possible to make thinner Walls with smaller sizes of tubes than has heretofore been thought possible of attainment by the known processes and apparatus. In Fi 2 the rolling-tubes are in the form of disks and N. The plugs B, C, and D are substantially the same as in Fig. 1. Several adjustment-washers 16 and 18 are shown, and the exterior rolling-surfaces of the rolls or disks M and N are also shown adjustable by means of the removable rings 20 and 21 secured by adjustable bolts 22 and backed by washers 23 and 24. This constructionis valuable not only as permitting adjustment, if necessary, of the width of the pass, but more particularly as permitting the com ensation for the wearin away of the rol in surfaces. As the s aces wear away add itional annular washers 23 and 24 may be inserted or thicker ones substituted for those already in place.
Fi 3 differs in principle from Figs. 1 and 2 on y in the omission of the intermediate lug C. This figure therefore provides only or the initial action upon the p ug B and the smoothing and finishing action .upon the phig D. I
ig. 4, on the other hand, shows three successive plu s C for thinning the Wall of the tube, and t e rolls P Q have successive sets of cooperating, converging, and diverging surfaces 112 113212 213 312 313. The plu D cooperates with the rolling-surfaces 14, t at correspond with surfaces 14!. in the other figures. In this figure it will be seen that the metal is compressed against the expanding plu -surfaces and reduced in thickness, Whi e being enlarged in diameter, and then it is again compressed, so as to reduce the external diameter and again rolled thinner upon an expanding-surface, and so on to the final finishing-plug D. The process disclosed s17,7ee
in this application to be carried out b the a paratus described and illustrated orms t e subject-matter of a separate atent application, Serial No. 201,077, filed April 1, 1904 but obviously some features of this a paratus may be used Without others and t e invention may be embodied in widely-varying forms.
Therefore, Without the invention to the constructions shown and described nor enumerating equivalents, I claim and desire to secure by Letters Patent the following:
1. In a paratus for cross-rolling tubes or blanks, ro mechanismcom rising apiercing lug or mandrel, means f dr forcing the bl nk on said piercing-plug, diverging rollwalls for e anding, elongating and simultaneously riiducing the thickness of the blank on said plug, converging roll-Walls for externally compressing the blank, asecond plug or mandrel rotatable independently of sai against said first-named plug,
first-named plug, roll-walls for again expanding, elo ating and reducing the thickness of the bla u on said second-named plug, an independent y-rotatable smoothing-mandrel, and roll-walls for compressing and smoothing the tube on said smoothing-mandrel.
2. In a paratus for cross-rolling tubes or blanks, rolihng mechanism com a piercg lug or mandrel, means or forcing the bla on said piercing-plug, diverging rollwalls for e an elongating and simultaneously re ucing the thickness of the blank on said plug, conver roll-Walls for externally compressing the lank, an independently-rotatable smoothing-mandrel, and rollwalls for compressing and smoothing the tube on said smoothing-mandrel.
3. In a paratus for cross-rolling tubes or blanks,ro gmechanism com rising apiercingnilug or mandrel, means f dr forcing the bla on said piercing-plug, diverging roll- Walls for expanding, elo ating and simultaneously reducing the thil mess of the blank on said lug, a second plu or mandrel rotatable in ependently of sai first-named plug, and roll-walls for a ain expanding, elongating and reducing the t 'ckness of the plug upon said second-named plug.
4. In apparatus for cross-rolling tubes or blanks in a heated state, the combination of a plurali y of interior plugs or mandrels, each rotatable at a different rate of speed, a plurality of externally rolling-bodies diiierent portions of each of which rotate at different rates of speed forming a single pass and provided with rolling-surfaces between which the metal is first pressed against and expanded and reduced upon one of said interior plugs and thereafter rolled upon another of sai interior plugs between rolling portions of the external rolls that are rotating with a higher peripheral speed than those pressing for substantially the purposes set forth.
plurality of externally rolling-bodies forming a single pass, said rolling-bodies being constructed and fitted to rotate at a greater fperipheral speed at the rear end than at the ward end of the pass, thereby causing an elongat' effect upon the tubular wall in the pass, or substantially the purposes set forth. 6. In apparatus for cross-rolling tubes or blanks, rolhng mechanism com rislng a piercing plug or mandrel, means or forcing the blank on said piercing-plug, diverging rollwalls for expanding, elon ating and simultaneously reducing the thic ess of the blank on said plug, converging roll-walls for externally compressing the blank, a second plu or mandrel rotatable independently of said first-named plug, and roll-walls for againexpending, elon ating and reducing the thickniess of the b ank upon said second-named u p 7% In a aratus for cross-rolling tubular bodies or l i l anks in a heated state, the combination of a lurality of exterior rolling bodies, a plurahty of independently-rotatable interior bodies, said exterior and interior bodies constituting means for rolling and reducing the heated metal in a single pass upon the interior bodies in succession, and between said bodies and the exterior bodies, for substantially the purposes set forth.
8. In apparatus for cross-rolling tubular bodies or blanks in a heated state, the combination of means for simultaneously expanding and reducing the thickness of the heated metal between interior and exterior expanding-surfaces, a cylindrical interior supportingbody, rotatable independently of said interior expanding-surface, and means for subsequetly compressing and smoothing the metal inside and out upon said substantially cylindrical interior supporting-body in the same pass, for substantially the purposes set forth. 9. A rolling mill, having a plurality of rolls forming a pass, a plurality of mandrels supported in succession in the said pass, and means for adjusting one portion of the active rolling-surface of one of the rolls relatively to the other ortions, for substantially the purposes set orth.
10. In apparatus forcross-rolling tubes or blanks, rolhng mechanism comprising a piercmg In or mandrel, conve g roll-Walls for orclng the blank on sai rercing-plug, diverging roll-walls for expan g, elon ating and simultaneously reducing the thickness of the blank on said plug, converging roll -walls for externally compressing the blank, an independently-rotatable smoothing mandrel, and roll-walls for compressing and smoothing the tube on said smoothingmandrel.
IIS
11. In apparatus for cross-rolling tubes or ing, elongating and reducing the thickness of 10 blanks,roll1ng mechanism comprising a piercthe blank upon said second-named plu ing in or mandrel, conver g roll-walls In testimony whereof I have signe this for dorcmg the blank on sai iercing-plug, specification in the presence of two subscrib diverging roll-walls for expan 'ng, elongating Witnesses. ing and simultaneously reducing the thick- I JOHN H. NICHOLSON. ness of the blank on said plug, a second plu Witnesses: or mandrel rotatable independently of said HELEN WOLFE,
first-named plug, roll-walls for again expand- H. W. PHELPS.
US20107804A 1904-04-01 1904-04-01 Apparatus for cross-rolling tubular bodies or blanks. Expired - Lifetime US817796A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4392369A (en) * 1980-04-01 1983-07-12 Mannesmann Aktiengesellschaft Diagonal rolling of hollow stock

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4392369A (en) * 1980-04-01 1983-07-12 Mannesmann Aktiengesellschaft Diagonal rolling of hollow stock

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