US1928741A - Rolling mill of the pilgrim-step type for the manufacture of metallic tubes - Google Patents

Description

Oct. 3, 1933. L. TSCHULENK ROLLING MILL OF THE PILGRIM STEP TYPE FOR THE MANIjFACTURE OF METALLIC TUBES Filed June 8, 1931 4 Sheets-Sheet 1 3 ROLLING MILL OF THE PILGRIM STEP TYPE FOR THE MANUFACTURE OF METALLIC TUBES L. TSCHULEN K Filed June 8, 1931 4 Sheets-Sheet 2 NM Wm R u z j 1 n. u v u 1, R K n n. i N u m 8, 1931 4 Sheets-Sheet 3 I 0 0m 40 8 M ||l llll III. N .lzl l L L. TSCHULENK Filed June Oct. 3, 1933. ROLLING MILL OF THE PILGRIM' STEP TYPE FOR THE MANUFACTURE OF METALLIC TUBES Oct. 3, 1933. L. TSCHULENK 1,928,741

ROLLING MILL OF THE PILGRIM STEP TYPE FOR THE MANUFACTURE OF METALLIC TUBES Filed June 8, 1931 4 Sheets Sheet 4 26 I .To/m/ Patented Oct. 3, 1933 ROLLING mu.

ma non 'rrrr: TALLIC 'rcass OF THE PILGRm-STEP MANUFACTURE OF ME- Leopold Tschulenk, liiahrisch-Ostrau-Witkowitz, Czechoslovakia Application June 8, 1931, Serial No. 543,058, and

in Germany May 20, 1930 4 Claims. (CL 80-14) My invention relates to a rolling machine or mill of the pilgrim-step type for manufacturing swing metallic tubes or pipes, and more particularly to a rolling mill of the said character provided with oscillating or reciprocating rolling segments adapted to be operated hydraulically,

and it consists in the combinations, constructions and arrangements herein described and claimed.

It has been suggested heretofore to use, in connection'with rolling mills having oscillating rolling members of segmental shape, pressure liquid cylinders disposed horizontally in the rear of the supporting structure for the driving purpose.

In contradistinction to the state of the art as above recited the pressure liquid cylinders of the rolling constructed in accordance with the present invention are arranged in that vertical plane of the roll supporting standard or structure in which the points of connection between the driving means and the oscillatory rolls or roll segments are situated.

The advantages resulting from such construction and arrangement reside, in the first line, in a very compact form requiring butlittle space for accommodation and ensuring best possible access to all parts-of the rolling mill for control, repair and particularly respecting conveyance and manipulation of the work under treatment. A further advantage resides in the complete positive closure or consumption of forces in the roll supporting standard during operation so that large encumbering and expensive foundations need not be provided for the reception of free forces.

Rolling mills of the pilgrim-step type as hitherto constructed for the manufacture of tubes and pipes are almost exclusively provided with revolving rolls and correspondingly revolving power engines, and the eificiency thereof is limited to the manufacture of tubes of a diameter below or not exceeding beyond about 20.inches since otherwise, that is to say, in case of larger cross-sectional areas the mill would be too bulky and the expenses to be incurred for the construction and defrayed'for the operation of such a huge machinery would be excessive and not repay.

As contrasted with the known rolling mills of the pilgrim-step type a rolling mill constructed in accordance with the present invention can be given any desirable dimensions for rolling tubes of practically largest cross-sectional areas, because its weight in general is far inferior to that a of a corresponding mill provided with revol rolls and, in economical regards, the operation or drive by means of a pressure liquid'ls much less expensive than a drive through the agency of large slow running electromotors.

Another important feature of my invention is the provision of a very short, reciprocating mandrel whereof the length is actually only a little in excess of the developed calibre or arenate surface of the rolling segments. Due to this feature the hollow blank to be rolled will not cool down so rapidly as in a mill as hitherto constructed and provided with the usual mandrels of a length more or less in excess of that of the work under treatment.

These and other features of my invention will more fully appear in the following description or will be obvious therefrom. In the accompanying drawings forming a part of this specification and showing, for p p ses of exemplification, a preferred form and manner in which the invention may be embodied and practised, but without limiting the claimed invention to such illustrative instance, and in which more than two rolling ments or members are provided in one plane, although the advantages inherent in the present invention will also be secured even in case of providing two working members only.

In the accompanying drawings wherein like characters designate like parts throughout the several views:

Figure 1 is a view in vertical longitudinal section of a rolling mill constructed in accordance with the present invention,

Figure 2 is a view in horizontal section taken on the line 2-2 of Figure 1,

- Figure 3 is a view in full vertical cross-section taken on the line 3-3 and in half-section taken on the line e-,f of Figures 1 and 2,

Figure 4 is a view in vertical section on the line 4-4 of Figures 1 and 2,

Figure 5 is a view in vertical section on the line 5-5 of Figures land 2,

Figure 6 is a view in vertical section taken on the line 6-6 of 1 and 2,

Figure 7 is a view in vertical section on the line 7-7 of Figures 1 and 2 and Figures 8 and 9 are sectional views of the device for turning and feeding the hollow blank, supplementary to Figure 7, but shown on an enlarged scale.

In Figure 1 the operating parts of the rolling mill are shown in the position they occupy at the moment of the beginning of the rolling operation while Figure 2 illustrates the position thereof at the time immediately upon the insertion of the big hollow blank 1. In order to illustrate the advantages of the invention in a best possible way,

the embodiment including the provision or four segmentalrollingmembers2adaptedtooscillate or reciprocate on the Pilgrim-step principle and -mountedinacommonverticalplanehasbeen shownin' the drawings. The said segmental rolling members 2 are shaped to form or provided with lever-like extensions 3. pivotailyco'nnected with short pressure-rods'4 which in turn are pivotally mounted in hydraulic plungers 5 so that the latter will operate to reciprocate the rods 4 and thereby impart motion to the rolling members 2. This arrangement isoi particular advantage inasmuch as any auxiliary means for guidingtherods4maybedispensedwith. For the purpose of returning the working plungers 5 and the rolling members 2 back to the outer or initial positions, separate returning plungers 6 are provided. The said auxiliary plungers 6 disposed in pressure-water cylinders. 11 are connected with the working plungers 5 by means or 'crouheads 7 and pull rods 8; The'iour oscillating or reciprocating rolling members 2 are supported in bearings provided in the standard 9 and the hydraulic cylinders 10 and 11 of the working plungers 5 and the returning plungers 6, v respectively, are also connected or integr l with the standard a. ;-In order to prevent the latter 'irom being detrimentally aiiected by bending stresses during the rolling operation, the diemetrically opposite pressure-water cylinders are interconnected in pairs, by means of strong powertul rods 12. The rolling members 2 are con- Enected with a carriage 14 by means of horizontal .-.rods 13 so that the carriage will co-operate to reciprocate simultaneously with the rolling mem- -.bers 2 the connection of the latter with the said carriage also involving a positive interconnection -oi' the said rolling members'and consequently a 'positiv'einterdependence respecting the moments -oi the same. The carriage 14 serves for the re-' ception and support of the hollow, cylindrical blank 1 prior to and .during the rolling operation. .-In the-rolling mills o! the pilgrim-step type as =hitherto constructed or suggested, the rolling mandrel is'usu'allyoia greater-length thanthe blanks to be rolled. The mandrel '15 provided in .a rolling mill constructed according to the present invention, however, is comparatively short. and, as regards its length a littlein excess only or thelengthoithecalibre orrollingsuriaceoi the. rolling members 2. A-turther advantage of the mandrel 15 resides in its positive connectionwith the rolling members 2'so'as to'be compelled to reciprocate simul with the oscillating.

The operation of the rolling-mill hereinbeiore "describedisas-followst A Thetubularblank iisplacedonthecarriage 14 at a. point between the'standard' 9 and the withdrawn mandrel 15 with the abutting bushing ,30 therein likewisewithdrawmas will be seen in Figure 2. The inner diamctcr'ofthe blank 1 ua-little greater than that otthe finished tube. or theouter diameteroi the mandrel 15.'The latter is ilrmlyattached toarod 16, as usually, which is hollow and adapted to be cooled by means of am suitable cooling agent such as water. The'flrstoperationnowis topushthe mandrel -15by meansotitsrod16,!orwardsthroughthe blanksoasi'obringthesametotheirontoithe blank and into its working position between the rolling members2aswill-beseen inFigure 1.

The operation of advancing and withdrawing the rod 16-with the mandrel'iii maybe accom- PM with. t aid aw ppr priate In the embodiment shown the operation is etiected by means of a double-acting hydraulic cylinder 17 shown in Figures 1 and 2 with parts broken away which however will be sell-suggesting to the men of the art. v

The mandrel 15. is connected with the carriage 14 by means of the rod 16 due to the lockingot the latter through the agency of a locking slide 18, see Figure 6, so as to positively partake of the reciprocatory movement or the rolling-members a reversible electromotor 19, see Figure 6, adapt: ed to operate a worm-gear 20 and a threaded stem 21, being provided for raising and lowering the said locking slide 18.

Obviously after each working stroke or movement and subsequent back-lash or return movement of the rolling members 2 the tubular blank 1 must be advanced or fed a corresponding length by the mandrel 15 and simultaneously turned about its axis for at best degrees. To this end I provide an electromotor 22'which, through the agency of a suitable gearing including a worm 23, a worm-wheel 24 and a spur gear wheel 25, will transmit motion to two toothed wheels 26 keyed to the spindles 27 and therefore, adapted to impart motion to the latter. The nuts 28 engaging about the threaded spindles 27 are firmly secured to or integral with the carriage 14. The successive rotations of the spindles 27 cause the crosshead 29 to be displaced within the carriage 14 relatively to the standard 9 by a corresponding length. I

Mounted in the cross-head 29 is the abutting bushing 30 which is adapted to advance together with the advancing cross-head 29 so as to feed the tubular blank 1 on the mandrel towards the rolling members 2 by a corresponding length or -s tep. 'For the purpose of compensating for the little diiterences in speed between the cross-head 29 and the, abutting bushing 30 during the working stroke or operation of the-rolling members 2,

.due to the unequal pressures of the latter-on the tubular blank, a yielding means such as a coiled spring 31, as shown in Figure 1, may be provided.

Keyed to the threaded spindles 27 are pinions- 32 which are adapted to transmit rotary motion to the gear 33. The latter is nrmly connected or I integral with the bushing 34 through which the elongation or rear end 35-01 the mandrel rod 16 passes. Mounted in the section 35 of the rod 16125 .are sliding keys 36, so that upon rotation of the bushing 34 the rod section 35, the rod 16 and the mandrel 15 attached to the latter will be caused to rotate at the same time.

- Similar sliding keys 37 are provided 16 and adapted to cause the abutting bushing 30 to also rotate simultaneously with the rod 16. The rolling mandrel, when rotated, in turn causes the blank to also rotate, due to frictional engagement, sifnce immediately upon the beginning of the roll- 135 ing operation, the blank will be compressed by the rolling members to firmly adhere to the mandrel.. Preferably I insert a suitable ball-bearing 38 in the cross-head 29 between the annular rearend flange thereof and the step-wise rotating'ym coiled spring 31, in order to reduce friction.

. It will beseen that the described arrangementsafl'ord the possibility of .teeding the. tubular blank after each working stroke of the rolling members 2, by a corresponding or adequate length and turn-"1 ing the blank atthesametime'by apartialrotation. Obviously the blank willthus be led and turnedalwaysatterthesamehasbeeniullyre-- ieesediromthepressureoitherollingmembers.

.. operation described repeats as 16 cntherod as required for completely rolling the blank to the shape and size of a finished tube or, in other words, until the finished tube is extrudedfrom the mandrel, when the locking slide 18 will be raised by the motor 19 and the rod 16 together with the mandrel 15, the rod section 35 and the hydraulic cylinder 17 will be withdrawn into the position shown in Figure 2, so that the place or space for the insertion of a further blank will be clear for a next rolling operation.

The rear section 35 of the rod participates in the reciprocatory movement of the carriage 14, as already intimated hereinbefore. Now in order to prevent the reciprocating rod section 35, while the mandrel 15 is in its working position, from moving the piston rod 39 of the hydraulic-cylinder 17 idly to and fro I provide a somewhat enlarged bore 40 in the extremity of the rod section 35. The length of this enlarged bore 40 corresponds to the length of the travel or stroke of the carriage, so that the head 41 of the piston rod 39 of the hydraulic cylinder can remain at test during the rolling operation properly speaking.

In order to facilitate the stepwise rotation of the tubular blank 1, I provide a system of rollers 42 in the carriage 14, as shown in Figure 4, adapted to be adjusted to conform to the external diameter of the blank 1.

In the embodiment shown separate working plungers 5 and separate return-plungers 6 are provided for the reason that in case of leakage the stuffing-boxes can be readjusted or the packing thereof renewed, or filled up in a ready and rapid manner in order to remove the defect without unduly interrupting thereby the operation of the mill.

Obviously, however, it is possible to substitute for each single-acting plunger a hydraulic cylinder with a double-acting piston in connection with each rolling member 2. On the other hand in case of providing working and return-plungers as shown in the embodiment described, the pressure rods 4 are not absolutely necessary and may be dispensed with, and also in case of substituting said hydraulic cylinders for the plungers as above contemplated, there would be no absolute necessity of providing such pressure rods which rather might be replaced, if desired or preferred, by any other appropriate or equivalent constructional means.

I am also aware that various other changes in the arrangement, construction and combination of the several parts of my improved rolling mill can be made and substituted for those herein shown and described without in the least departing from the nature and principle of my invention. I would, therefore, have it understood that I' do not limit myself thereto, but hold myself at liberty to make such departures therefrom as fairly fall within the true spirit and scope of my invention and the spirit and scope of the appended claims.

What I claim is:

1. A rolling mill of the pilgrim-step type for the manufacture of metallic tubes having big diameters comprising a supporting frame, a plurality of oscillating rolling elements with their working faces shaped according to a part of the inner surface of a torus, means for hydraulically operating the said rolling elements including hydraulic cylinders, the latter being carried by the supporting frame in juxtaposition to each other, all of their longitudinal middle-axes radiating outwardly from the axis of the mandrel and being contained in the same vertical plane, the latter being situated at right angles to the axis of the mandrel and in front of the'blank.

2. A rol1ing.mill of the pilgrim-step type for the manufacture of metallic tubes having big diameters comprising a supporting frame, a plurality of oscillating rolling members with their working faces shaped according to a part of the inner surface of a torus, means for hydraulically operating the said rolling members including hydraulic cylinders with plungers and short pressure-rods, connecting the said plungers with the rolling members, the cylinders and plungers being carried by the supporting frame, all of their longitudinal middle-axes radiating outwardly from the axis of the mandrel and being contained in the same vertical plane, the. latter being situated at right angles to the axis of the mandrel and in front of the blank. I

3. A rolling mill of the pilgrim-step type for the manufacture of metallic tubes having big diameters comprising a supporting frame, a plurality of oscillating rolling members with their working faces shaped according to a part of the inner surface of a torus, a mandrel being a little longer than the working face of the rolling members, the latter being attached to a rod connected with a carriage for the reception and stepwise feed of the tubular blank, the carriage being arranged behind the supporting frame and connected with the rolling members by connecting rods, the'mandrel and the carriage being arranged to positively follow the reciprocating movement of the rolling members, means for hy draulically operating the rolling members including hydraulic cylinders, the longitudinal middleaxes of the same radiating outwardly from the axis of the mandrel and being contained in the same vertical plane, the latter being situated at right angles to the axis of the mandrel and in front of the blank.

4.' A rolling mill of the pilgrim-step type for the manufacture of metallic tubes having big diameters comprising a supporting frame, a plurality of oscillating rolling members with their workingfaces shaped according to a part of the inner surface of a torus, a mandrel being a little longer than the working face of the rolling members and being attached to a displaceable rod, the latter being connected to a carriage for the reception and stepwise feed of the tubular blank by a looking slide, the slide being arranged behind the supporting frameand connected with the rolling members by connecting rods, the mandrel and the carriage being arranged to positively follow the reciprocating movement of the rolling members, the longitudinal middle-axes of the same radiating outwardly from the axis of the mandrel and being contained in the same vertical plane, the latter being situated at right angles to the axis of the mandrel and in front of the blank.

- LEOPOLD TSCHULENK.

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