US2099497A - Guide for tube rolling mills - Google Patents

Description

' Nov. 16, 1937. J. w. OFFUTT I 2,099,497.

GUIDE FOR TUBE ROLLING MILL S Filed 'May 20, 19Z 6 2 Sheets-Sheetl JOHN W. OFFUTT,

Nov 16, 1937.

J; w. OFFUTT GUIDE FOR TUBE ROLLING MILLS Filed May 20, 1956 2 Sheets-Sheet 2 lm enfor. f JOHN W. OFFUTT,

s PATENT OFFICE GUIDE FOR TUBE ROLLING MILLS John W. Ofintt, Ellwood City, Pa., assig'nor to gational Tube Company, a corporation of New erscy Application May 20, 1936, Serial No. some UNITED STATE This invention relates to guides, .and more particularly to those used in seamless pipe and tube mills as an integral part thereof for preventing excessive circumferential distortion of the blank, or work-piece, during processing.

In the manufacture of seamless tubes a solid, and round, billet is heated to a forging temperature and pierced. The dimensional characteristicsof the pierced billet, or work-piece, are subsequently changed by expanding or reducing its diameter and/or wall thickness. During piercing and most of these subsequent operations, the work-piece is internally supported by means of a plug or mandrel.

The forces employed to eflect displacement of the heated work-piece comprise a plurality of metal-working rolls whose axes ase usually angularly inclined to the line of pass, which effects a combined rotary and longitudinal feeding eflect. While the work-piece is being acted upon by the metal-working rolls it becomes necessarily distorted at the metal-displacement area of the pass. This distortion is usually ovalshaped but is subject to modification dependent,

of course, upon the elements comprising the pass.

In order to prevent excessive diameter expansionfor unit area of reduction it is necessary to constrict this distortion during formation. This is usually accomplished by disposing supplementary guide members in the pass.

- The usual form of guide is in the nature of p a pair of stationary elements disposed intermediate the metal working rolls, one above and one below the line ofpass. These guides are, of course, subject to a very great abrasive action and intenseheat from the work-piece. In some instances, the temperature of the guide is raised to a point where the metal of which it is composed becomes plastic and begins to flow. Conditionssuch as these soon cause the guides to become unfit for use, due to their wearing away to such a marked degree as not to present the Another object is to provide a guide of the class described which will present a surface for contacting the work-piece which changes over a comparatively large area; thus distributing the wear and heating effects rather than concen-- 5 trating them at one point, which is the effect rendered by conventional devices.

A further object of the invention is to provide a novel guide having the characteristics referred to, but one which may, at the same time, be 10 easily and inexpensively installed on existing types of mills.

The foregoing and further objects will be apparent after referring to the drawings, in which:

Figure 1 is a sectional end elevation of the 15 apparatus of the invention as applied to a seamless tube mill.

Figure 2 is a side elevation of the apparatus of Figure 1.

, Figure 3 is a side elevation of a modified form 20 of the invention.

Figure 4 is a sectional side elevation of a detail of Figure 3. I

Figure 5 is a plan of the detail of Figure 4.

Figures 6 and 7 are end elevations of the detail 25 of Figure 4.

Referring more particularly to the drawings, the numeral 2 designates a pair of metal-working rolls which are shown as being of the well known barrel type, havingtheir axes oppositely 30 inclined with respect to the line of pass they are intended to define. It' is to'be understood that any conventional type of piercing point, plug or mandrel may be disposed, if desired, between the metal-working rolls 2 in order to internally as support the work-piece while it is being processed according to any of the current seamless tube practices.

A pair of supports 3 are arranged above and below the horizontal center line of the-mill com- 40 prising the metal-working rolls 2, and are recessed as at 4. A pin 5 is disposed in the aperture l in each pair of supports 3, and each carries a swivel-block I which is journaled thereon. Each of the swivel-blocks 1 is provided with a 45 threaded aperture 8.

The guiding members of the invention are generally indicated at l0, and provide curved contact faces II, which are composed of inserts of a high grade heat and wear resistant material. The effective area of the contact faces I: of the guiding members I II is several times as long as the length required for conventional stationary guides.

The guiding members I 0 are each provided with a threaded aperture I5 in which there is disposed a screw I6, which also extends into the threaded aperture 8 of one of theswivel-blccks 1. An adjusting nut I1 is secured to the intermediate portion of each of the .screws I6, in order that the disposition of the guiding members III may be adjusted with respect to the swivel-blocks I. The guiding members I0 have a slotted aperture I8 in both of their sides, together with a transversely extending intercommunicating aperture I9.

A support 2I is provided at each end of the mill comprising the working rolls 2, and each has an upper and lower aperture 22 extending therethrough. A pair of'shafts 23 is slidablysupported in the upper and lower apertures 22, in the supports 2I, and are each threaded on one of their ends, as at 24. Each of the shafts 23 is provided intermediate its ends with a block 25 which is of such cross-section as to slidably fit within the transversely extending aperture I9 in one of the guiding members Ill. The blocks 25, on the shafts 23, are each apertured as at 26 to receive a pin 21 which extends from both sides thereof to ride in the slotted apertures I8 in the guiding members III.

A worm gear 29 is provided for each of the shafts 23, and are each internally threaded, as at 3|, to cooperate with the threads 24. A vertically disposed shaft 32 is suitably journaled on the support 2I which is adjacent the threaded portions 24' of the shafts 23. A pair of worms 33 are secured to the shaft 32 in spaced relationship such as will permit their enmeshment with the worm gears 29. A motor 35 is secured to the support 2| carrying the vertically disposed shaft 32, and drives the latter through a coupling 36. The motor 35 is preferably one which may be rapidly reversed.

In operation, the motor 35 is driven in such manner as to move the shafts 23, in the apertures 22, and accordingly move the guiding members .Ill toward the outlet end of the pass, and thus present successive areas of the inserts I2 for contact with a work-piece progressing between the metal working rolls 2. In this manner, wear will be evenly distributed over the inserts I 2, and result in their life of service being greatly increased. In certain cases, it will prove highly desirable to drive the motor 35 at a high rate of speed alternately in both directions in order that the guiding members I0 may make several oscillations during the processing of a single workpiece.

In Figure 3 of the drawings, a modified form of the invention is shown as comprising, in part, a

pair of shafts 38 which are journaled on a support 39. Each of these shafts 33 carries a crank 40 on its end adjacent the guiding members I0.

Each of the cranks 40 carries a pin M, and a similar pin 20 is provided on each 'of the guiding members II) in lieu of the apertures I3 and I9. A link 42 is connected between the bosses 23 and 4|, on the guide members III and cranks 4|, respectively. Each of the shafts 33 also carries a worm gear 44, which is adapted to be in driving connection with the worm 33 on the shaft 32, previously mentioned. The elements of this modification of the invention are somewhat more compact than those described in-Figure 2, and

prising the profiling of the contact faces I2 to provide a larger opening at the end of their movement toward the outlet end of the pass than at the beginning thereof. The guiding members I0 may thus be reciprocated to the ends of their movement to free a work-piece which might otherwise be stuck.

.This modification provides a pair of contact faces similar, in a broad sense, to those of the inserts I2, but are taper grooved, as at 46, and slightly flared toward one end, as at 48. In practicing this form of the invention, the motor 34 is not driven during the processing of the metal working rolls 2, but the guiding blocks Ill may be suitably adjusted to accommodate various diameters of work-piece. The metal working rolls 2 may therefore be adjusted in accordance with well known practice, when changing over to another sized work-piece, and the guiding members Ill moved forwardly and backwardly in the pass in such a manner as to present a smaller or larger semicircular contact face. It will be readily apparent to those skilled in the art that a great saving in time will be effected in settingup" the mill for a changed size.

While I have shown and described several specific embodiments of my invention, it will be understood that I do not wish to be limited exactly thereto, since various modifications may be made without departing from the scope of my invention, as defined by the following claims.

I claim:

1. Apparatus for forming metallic tubular blanks comprising, in combination, a plurality of metal-working rolls which are constructed and arranged. to helically advance a work-piece in a continuous manner, at least one guide member disposed to present its guiding surface to that portion of the work-piece which is in the pass of said metal-working rolls, said guide member having. its guiding surface longitudinally arced and being capable of only limited swinging movement in a plane through the axis of the work-piece to present different longitudinal portions of its guiding surface thereto, .and means for imparting swinging movement to said guide member whereby excessive localized heating and wearing of said guiding surface is substantially reduced.

2. Apparatus for forming metallic tubular its guiding surface tothat portion of the workpiece which is in the pass of said metal-working rolls, said stationary guide member having its guiding surface longitudinally arced and being capable of only limited swinging movement in a plane through the axis of the work-piece,

and means for imparting swinging movement to said guide members to present different longitudinal portions of its guiding surface to successive work-pieces processed by said metal-work-, ing rolls whereby excessive localized heating and wearing of said guiding surface is substantially reduced.

3.- Apparatus for forming metallic tubular blanks comprising, in combination, a plurality of metal-working rolls constructed and arranged to helically advance a work-piece in a' continuous manner, at least one guide member disposed to present its guiding surface to that portion of the work-piece which is'in the pass of said metalworking rolls and capable of only limited swinging movement in a plane through the axis of the work-piece, the guiding surface of said guide member being longitudinally curved on an are having its focus at substantially the axis about which it swings to present different longitudinal portions of its guiding surface thereto while maintaining a guide pass of constant size, and means for imparting swinging movement to said guide member during the passage of the workpiece between said metal-working rolls, whereby excessive localized heating and wearing of said guiding surface is substantially reduced.

4. Apparatus for forming metallic tubular blanks comprising, in combination, a plurality of metal-working rolls which are constructed and arranged to hlically advance a workpiece in a continuous manner, and at least one guide member disposed to present its guiding surface to that portion of the work-piece which is in the pass of said metal-working rolls, said guide member being capable of only limited swinging movement in a plane through the axis of the workpiece to present different longitudinal portions of its guiding surface thereto, the guiding surface of said guide member having a groove of varying diameter which is longitudinally curved on an are having its focus ofiset with respect to the axis about which said guide member swings,

and means for imparting swinging movement to said guide member to produce guide passes of different sizes.

\ JOHN W. OFFUTT.

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