US 3808863 A
This invention relates to rolling elongated bars between a backed-up forming roller and die means. The die means is preferably formed by a pair of rollers which most conveniently roll T-section bar. The die means may alternatively be a long die. Containment means is provided to prevent the die means bursting outwardly during rolling.
Description (OCR text may contain errors)
United States Patent [191 Marcovitch 1 FORMING OF ARTICLES BY ROLLING  Appl. No.: 185,333
Related U.S. Application Data  Continuation of Ser. No. 889,627, Dec. 31, 1969,
 Foreign Application Priority Data June 18, 1969 South Africa 69/4340 Feb. 14, 1966 South Africa 66/804  U.S. CL 72/199, 72/177, 72/241, 72/224  Int. Cl B2lb 1/08  Field of Search 72/225, 177, 199, 179., 72/224, 241, 242; 29/1495 C  I References Cited UNITED STATES PATENTS 1,856,269 5/1932 Schultz et a1. 72/224 .[451 May 7,1974
Primary Examiner-Milton S. Mehr Attorney, Agent, or Firm-Young & Thompson [5 7] ABSTRACT This invention relates to rolling elongated bars between a backed-up forming roller and die means. The
2 Claims, 8 Drawing Figures 1 FORMING OF ARTICLES BY ROLLING This is a continuation, of application Ser. No. 889,627, filed Dec. 3l, 1969, and now abandoned.
This invention relates to apparatus for forming metal articles by rolling.
According to this invention there is provided apparatus for forming ended metal articles by rolling, comprising a forming roll, back-up rolls on which the forming roll is rotatably mounted, and die means; the die means and the forming roll being formed with cooperating surface means one of which defines a recess and the other of which fits closely into the recess and defines therewith a working space in which a workpiece may be shaped by. the two surface means. Preferably containment means is provided to act on the sides of the roll or die means in which the recess is formed to balance outward forces during the forming operation.
The die means may be formed as an elongated die or may be comprised by one or two or more die rolls. The die means is conveniently also backed up and the recess or surface means is preferably formed in the die means. The containment means may also be in the form of additional back-up rolls where the die means comprises the roll or rolls. Alternatively the containment means may comprise a plurality of jacks, which where the die means comprises a roll or rolls are arranged on the axis of the roll or rolls. I
When the die means is formed as a pair of rolls these may be arranged with their axes slightly inclined to one another, and may be spaced apart so that the recess formed thereby has 'no base.
When the die means is formed as a roll or rolls,a bending roll may be provided adjacent the die means continuously to bend the formed workpiece.
When the die means comprises an elongated die, the forming roll and its back-rolls may conveniently be mounted on a bracket which is movable on a back-up surface relative to the preferably stationary die.
Embodiments of the invention will now be described by way of example with reference to the accompanying drawings.
SHORT DESCRIPTION OF DRAWINGS In the drawings:
FIG. 1 is a section through apparatus for rolling T section bar, the section being taken on line 1 l of FIG. 2;
FIG. 2 is a side view of the apparatus of FIG. 1;
FIG. 3 is a side view of the apparatus for rolling chanin the form of a pair of die rolls 12.
The forming roll 11 has an enlarged central portion 14 with a cylindrical working surface, and a pair of stout stub axles 15. The forming roll 11 is engaged by a back-up roll 16 of substantially greater diameter than the central portion 14 and having a recess 16a to accommodate the central portion 14. The axial length of contact between the stub axles 15 and the back-up rolls 16 is substantially greater than the axial length of the central portion 14 of the roll 11.
The die rolls 12 are arranged with their axes 17 inclined by a very small angle to one another and intersecting approximately mid-way along the length of the central portion 14, of the forming roll 11. The die rolls 12 are mounted on axles 18 carried in bearings 19 in the apparatus housing (indicated generally at 21).
Each roll 12 comprises a head portion 22 and a flange protion 23. The head portion 22 has a frustoconical rolling surface 24 which tapers to its outer end where it is provided with a domed top portion 25 having a frustoconical edge 26 which lies at right angles to the rolling surface 24. The front face 27 of the flange portion 23 is also frustoconical and lies parallel to the frustoconical edge 26 of the domed portion 25 of the head portion 22. The cone angles of surfaces 24, 26 and 27, the inclination of the die axes 17 and the disposition of the rolls 14 is such that (i) the parts of the surfaces 24 opposite the forming roll 11 are aligned and are parallel to the surface of the working surface of the central portion 14 of the forming roll 11, (ii) the front faces 27 of the flange portions 23 are spacedapart by nel section bar, the section being taken on line 3 3 FIGS. 1 AND 2 Referring now to FIGS. 1 and 2, the apparatus there shown'is the currently preferred embodiment of the invention. The apparatus is adapted to roll a T section the axial length of the forming roll 11 and closely receive part of the forming roll 11, therein, and (iii) the frustoconical edge portions 23 are spaced from one another.
The working surface of the portion 14 and the surfaces 24, 25 and 27 form a rolling recess in which a workpiece or stock is rolled. As the die rolls 12 are spaced apart the rolling recess is without a base for the space in which the leg 31 of the T section bar 10 is formed.
A pair of back-up rolls 28 having their axes at right angles to the axes 17 respectively are provided adjacent the location of the forming roll 1 1. These back-up rolls 28 are of substantial diameter and act on the rear face '35 of the flange portion 23 of the die rolls 12 to support rolls it is bent by the roll 34 into the appropriate arcuate shape with either the cross-piece or leg of the T innermost;
It will be seen that as the forming roll 11 is backed up by the large back-up rolls 16 and as the flange portions 23 of the die rolls 12 are held against bursting by the containment means, it is possible to act on the workpiece 10 with extremely high pressures acting on the part of the workpiece passing through the throat. These pressures may be of the order of one hundred and fifty tons per square inch or more. This enables a workpiece to be cold rolled into a T section in a minimum of passes and, in particular, normally in one pass.
It is also possible to produce a highly polished and accurately dimensioned T section with a relativelylong .central leg 31 from rough rectangular section stock or workpieces 32 billets 32.
It will also be appreciated that as the bar is ended,
i.e., it is not endless as, for example, a ring, the rolling recess is circumferentially wholly bounded and any reduction of the cross-section of the workpiece as compared to that of the stock 32 is compensated for by the elongation of the workpiece.
It must be pointed out, however, that due to the side entrapment and high intensities of pressure used, a large reduction in one pass is obtained as well as filling of all details. of the die space.
It is further pointed out that the severe side entrapment encourages filling of the die space and reduces tendency for the bar to enlongate instead of filling this die space.
FIGS. 3 AND 4 Apparatus for rolling channel section, ended bars 41 is shownin- FIGS. 3 and 4. This apparatus comprises a main forming roll 42 and die means in the form of-a single die roll 43. The forming roll 42 has an enlarged central portion 44 having a profiled working surface formed with a pair of steps 44a. The form roll 42 also has a pair of stout stub axles 45. The stub axles 45 are each engaged by a pair of back-up rolls 46 of substantially greater diameter than the central portion 44. The axial length of contact between the stub axles 45 and the back-up rolls 46 is substantially greater than the axial length of the central portion 44 of the roll 42.
The die roll 43 is arranged with its axis 47 parallel to the axis 48 of the roll 42 and is supported over its entire length by a pair of back-up rolls 49. An annular recess 51 is formed in the die roll 43. The enlarged central portion 44 of the forming roll 42 closely fits the recess 51 and the surfaces of the recess and the portion 44 define a rolling recess in which a rough, generally rectangular section workpiece 52 is cold rolled into a polished bar 41 of the desired and accurate section.
In order to pre-stress the die roll 43 and to prevent it bursting'under the-rolling forces a pair of hydraulic cylinders 54 are provided arranged with their axes aligned with the axis 47 of the roll 43 and carrying enlargements 55 at the ends of their piston rods 56. These enlargements 55, which can be in the form of pads, act
on the ends of the roll 43 and serve as containment means therefor. The piston rods may rotate with the roll 43 during operation of the apparatus. Alternatively the enlargements 55 may be rotatably mounted on the ends of the piston rods 56.
This apparatus will operate at pressures of the same order as those mentioned above for cold rolling the workpiece and as in the first described embodiment, a bending roller 57 may be provided to form arcuate bars 58, with the base of the channel section either inside or outside.
FIGS. 5 AND 6 In the apparatus shown in these Figures, the die means is in the form of an elongated, rigid fixed die 61 in the upper surface of which there is formed a rectan gular section recess 62. A forming roll 63 has an enlarged central portion 64 which has a profiled central working surface with side steps 64a and which closely fits the recess 62 so that the surfaces of the portion 64 and the recess 62 define a forming recess. Stout stub axles 65 project from the ends of the roll 63 and are supported by a pair of back-up rolls 66 which are of substantially greater diameter than the roll 63. The back-up rolls 66 are carried on a shaft 66a in a bracket 67 which is slidable on the underside of a rigid guide frame 68. The axial length of the contact between the stub axles 65 and the back-up rolls 66 is substantially greater than the axial length of the central portion 64 of the roll 63.
The side walls of the recess 62 would preferably be in the form of inserts resting against tapered wedges which may be withdrawn to release the workpiece from the die 61. Other ejection means may however be used for extracting the workpiece- In use, rough, rectangular section, cold stock 69 is inserted in the recess 62 in the die 61. The bracket 67 is caused to move along the frame 68 and the roll 63 cold rolls the stock 69 to form channel section bar 71. If desired the rolling can take place in a number of passes and the frame 68 moved towards the die 61 between each pass.
Here again the pressure intensities of the forming roll 63 on the workpiece 69 are of the order mentioned above. a
The die 61 is usually sufficiently strong to accommodate bursting forces. However, clamps (not shown) may be provided at spaced locations along the die 61 acting on the sides 72 of the die 61 to prestress it in order to enable it to withstand the immense bursting stresses imposed during the rolling operation.
It should be noted that where the axial length of the raised portion 64 of the forming roll 63 becomes long, it may be desirable to back up this portion 64 also with a complementarily shaped back-up roll. In any event, the backed up length of the roll 63 should always be in excess of the axial length of the portion 64.
In this figure there is shown a detail of the forming roller 73 and die 74 used in the apparatus of FIGS. 6 and 7 to produce T section bar 75. The forming roller 73 has a cylindrical central protion 76 of enlarged diameter. This portion 76 fits closely into the mouth of the'die-reeess 77.
With this arrangement it is possible to convert by cold rolling rectangular stock into T section bar 75, which may typically be 2 inches X I inch and of 0.040 inch wall thickness.
The forming roll may alternatively be supplemented with other forming rolls and/or carried as shown in and described with reference to FIGS. 19 and 20 of my co pending application Ser. No. 615,613 filed Feb. 13, 1967.
The apparatus shown in FIG. 8 is used for cold rolling T section workpieces and is similar to the apparatus of FIGS. 1 and 2 save that instead of using external die rolls 12, internal die rolls 81 are employed.
These die rolls 81 are of large diameter and are arranged with their axes 81a inclined at a large angle to each other. The forming roll 82 is received within the rolls 81 and are backed up by back-up rolls 8 3 rolling on stub axles 84 projecting from the central portion 85 of the forming roll 82. The central portion of 85 of the forming roll 82 fits closely into the recess formed by the GENERAL By fitting the forming roll closely into the die recess, the workpiece can be very accurately shaped by the die means and forming roll with no material overflow.
, The rolling operations could also take place with the metal hot or warm.
frustoconical working faces 86, 87 and 88 of the die The rolling of the workpiece is preferably carried out at a speed of the order of one hundred feet per minute to prevent undue scoring of the sides of the die recess by the sides of the enlarged central portions of the rollers. However this speed is determined by the hardness and other properties of thematerials used for these parts and may be greater or less as the case may be.
The invention is not limited to the precise constructional details hereinbefore described and illustrated in the drawings. Thus for example in the FlGS. l and 2, FIGS. 3 and 4 and FIG. 7 embodiments the die roll may be made up of three rolls bolted together. Similarly the die 61 may be made of three rectangular plates members bolted together.
1. Apparatus for forming metal articles by rolling,
comprising a forming roll .having working surface means, back-up rolls on which the forming roll is rotatably mounted, a die roll formed with a peripheral recess having working surface means, the forming roll fitting closely into the recess and defining therewith a working space in which a workpiece may be shaped by the two working surface means, and containment means comprised by a plurality of jacks provided with pressure pads acting on the end faces of said die roll.
2. Apparatus for forming metal channels by rolling from bar stock, comprising a forming roll having a working surface characterized by an enlarged central portion having a cylindrical peripheral surface terminating in first side surfaces substantially perpendicular to the axis of the forming roll, said forming roll having a pair of surfaces extending outwardly from said first side surfaces and terminating in second side surfaces substantially perpendicular to the axis of the forming roll, back-up rolls on which the forming roll is rotatably mounted in line contact, and a die roll having a peripheral recess complementary in shape to, but larger than, said enlarged central portion and in which said enlarged central portion is disposed, said peripheral recess being bounded endwise by end walls substantially perpendicular to the axis of the die roll and spaced apart a distance to receive said second side surfaces closely therebetween, whereby said forming roll and die define between them a rolling recess in which bar stock may be cold rolled to a channel of the desired and accurate CI'OSS section.