US2371671A - Metal rolling process - Google Patents

Description

March 20, 1945. H. BLOUNT ETAL 2,371,671

I METAL ROLLING PROCESS Filed March 23, 1943 2 Sheets-She et 1 Y INVENTORS Bzoww C. KLu DEEN' BY Mafch 20, 1945.

2,371, 71 METAL ROLLING PROCESS Fileduarch 23, 1943 2 she ets -sheet 2 F/a/s INVENTORS H. BLOUNT C. V

Patented Mar. 20, 1945 METAL some raocas's Harry Blount, Baltimore, and Carl V. Lundeen, Towson, Md., assignors to Western -Electric Company, Incorporated, New York, N. Y., a corporation of New York Application March 23, 1943, Serial No; 490,154

18 Claims.

This invention relates to metal rolling processes, and more particularly to processes for rolling continuous lengths of metal into strips.

The customary method of making strip is to reduce slabs by successive flat rolling operations wherein the size of the pass is decreased in each successive roll. This method necessarily results in both a lateral spread and an elongation of the metal.

In the past'metal ha been reshaped, when a lateral spreading of the metal was desired, by passing the metal through a series of rolls which exert pressure against the thinnest section there- ;of. a As pressure is applied to this section, it de;

creases in thickness and the metal flows laterally, with'a considerable amount of elongation.

1 However, in this operation the thin' section is put (Fig. 1) ispassed between rolls ll-Il (Fig. 2) provided with similar shaping surfaces formed of relatively narrow, parallel middle'surfaces, l2-I2 and inclined side-surfaces I3-l3 and "-14 intersecting therewith to form angles A-A, The

rod III is shaped by the'rolls H-ll into a continuou length of metal having a dumbbell-shaped cross-sectional area indicated-by the numeral ii. The area l5 comprises a flat middle section l6 having cylindroidal portions l'I-ll at the ends thereof and-is approximately equal in size to the I cross-sectional area of the original rod l0.

under a substantial tension by the application of pressure thereon, which may result in a rupture or break thereof.

The object of this invention isto provide new and improved processes for rolling metals.

In general, the invention comprises the process of reshaping a continuous length of metal by passing it through a series of forming rolls, and therein applying pressure to the metal so as to cause lateral spreadin yet not placing the sec- The length of metal having the cross-sectional area I5 is then passed between rolls l8-l8 (Fig. 3), having similar. shaping surfaces formed of parallel middle surfaces Ill-l9, whichare wider than the middle surfaces l2-l2 of the rolls ll-I l, intersected by -inclined side surfaces -20 and 2l-2l to form angles 3-3, which are greater than the angles A-A (Fig. 2). The rolls l8-l8 change the metal from a bar having the cross-sectional area designated by the numeral l5 into one having a cross-sectional area designated 22, comprising a flat central section 2 '23 having cylindroidal portions 24-24 at the ends tion being rolled under tension suflicient to cause a rupture or break therein.

Additional features andadvantages of the invention will become apparent from the following detailed description of a, specific embodiment thereof, when read in conjunction with the accompanying drawings, in which Fig. l is a cross-sectional view of the metal to be shaped;

Fig. 2 is a cross-sectional view of the metal being shaped, showing fragments of the rolls wherein the first deformation occurs;

Figs. 3, 4 and 5 are cross-sectional views of the metal being shaped, also showing fragments of the successive roll wherein the shaping is done;

Fig. 6 is a cross-sectional view of the metal in its final size and shape. also showing fragments of-the rolls wherein the metal is so shaped; and

Figs. '7 to 13, inclusive, arecross-sectional-views similar to. those shown in Figs. 1 to 6, which illustrate a modified method of rolling metals embodying the invention.

The particular embodiments of the invention disclosed in the accompanying drawing are particularly applicable to the rolling of copper rods to form fiat strips. In. the embodiment of the invention shown in Figs. 1 to 6, inclusive, a cold copper rod I0 having a circular cross-section 58 middle surfaces 32-33,wh ich are wider than the thereof. The central section 231s longer than the central section 16 of the cross-sectional area l5,

and the cylindroidal portions 24-24 are smaller than the cylindroidal portions l'l-ll of the area l5. Nevertheless, the cross-sectional area 22 is approximately equal to that of the original rod ID.

The length of metal is next passed through rolls 25-25 (Fig. 4) having similar shaping surfaces formed of parallel middle surfaces 28-26.

which are wider than the middle surfaces IS-l! of the rolls lS-IS, and inclined sidesurfaces 21-27 and 23-28 which intersect therewith to form angles C-C which are greater than the angles B-B (Fig. 3). The rolls 25-25 form the metal passing between them into a continuous length having a cross-sectional area indicated bythe numeral 29, comprising an elongated fiat central section 3|! having cylindroidal portions 3l-3l at the ends thereof. The cross-sectional area 23 is roughly equal to that of the original rod l0 and also to the cross-sectional area 22, although the central section 33 is longer than the corresponding section 23 of the area 22 and the cylindroidal portions 3l-3l are smaller than the corresponding portion 2l-24 of the area 22. The length'of metal is then passed between rolls 32-32 (Fig. 5) having similar forming faces comprising parallel middle surfaces 33-33 and inclined side surfaces 34-34 and 35-35. The

middle surfaces 26-26 of the rolls 25-25 (Fig. 4) are intersected by the inclined side surfaces 34-34 and 35-35 to form angles D-D which are greater than the angles C-C (Fig. 4). The rolls 32-32 convert the cross-sectional area 29 of the metal into a cross-sectional area designated 36 which is still nearly equal to that of the rod l and which comprises a fiat central portion 31 having flattened cylindroidal portions 38-38 at the ends thereof.

The metal having the cross-sectional area 36 is then passed between rolls 39-39 (Fig. 6) having flat parallel shaping faces 40-40. The rolls 39-39 form the metal into a continuous strip having a rectangular cross-sectional area designated 4|, which is the width of that desired in the final product. The material maybe worked further by conventional methods if it is desirable to reduce the thickness of the material which emerges from the rolls 39-39.

It is to be noted that the cross-sectional area of the metal being shaped is kept as nearly constant as possible until the metal enters the shap ing rolls 32-32, although the cross-sectional shape of the metal is changed as it advances through the successive preceding rolls. Even when the material has passed through the rolls 32-32, its cross-sectional area is still almost as great as that of the original rod 10.

In practicing the improved process, the circular copper rod I0 (Fig. l) is first passed between rolls ll-H (Fig. 2) wherein the shaping surfaces l2-l2, l3-l3 and l4-l4 thereof exert pressure upon the rod to form a continuous length of metal having a dumbbell-shaped -crosssectional area l5 comprising a flat section IS with cylindroids I'l-l'l at the ends thereof. the shape of the rolls il-Il it is possible to get a maximum of lateral spread of v the rod with a minimum of elongation, while the resulting crosssectional area I5 is approximately equal to the cross-sectional area of the rod ID.

The metal now having the cross-sectional area I5 is then passed between the rolls l8-I8 (Fig. 3). Since thewidth of the surfaces I9-l9 of the rolls I8-l8 is greater than that of the S111? faces I2-I2 of the rolls H-H (Fig. 2), the surfaces l9-i9 are necessarily wider than the cgntral flat portion I6 of the cross-sectional area B-B are greater than the angles A-A, the pressure exerted by the rolls l8-l8 through the shaping surfaces I9-I9, 20-20 and 2l-2I will be applied mainly upon the inner sides of the cylindroids l'l-I'l, resulting in a lateral spread of the cylindroids with a very small amount of elongation of the metal.

Thus, the rolls l8-l8 form the metal into a length having the cross-sectional area 22 composed of a flat section 23, which is wider than the flat section I6 (Fig. 2), with slightly flattened cylindroids 24-24 at the ends thereof. The cross-sectional area 22 is approximately equal tothe cross-sectional area of therod I0. Since the shaping pressure of the rolls l8-I8 is exerted principally upon the cylindroids IT-ll (Fig. 2), the flat center portion 23 (Fig. 3) is not put under any tension likely to rupture or break it.

After having been acted upon by the rolls I8-l8, the metal is next passed between the rolls 25-25 (Fig. 4). The width of the surfaces 26-26 of the rolls 25-25 is greater than that of the fiat section 23 of the cross-sectional area 22, and the angles C-C are greater than the Such being the case, and as the angles angles B-B As a result, the. pressure exerted by the rolls 25-25, through the shaping surfaces 26-26, 21-2! and 28-28, will likewise be applied mainly upon the inner sides of the cylindroids 24-24, which results in a lateral spread of the cylindroids with little elongation of the metal.

Hence, the rolls 25-25 form the metal into a continuous length having the cross-sectional Due .to

area designated 29, which is made up of a fiat section 30 which is wider than the flat section 23 (Fig. 3); with further flattened cylindroids 3l-3I at the ends thereof, while the cross-sectional area 29 is almost equal to the cross-sectional area of the original rod l0. As the forming pressure is exerted mainly upon the cylindroids 24-24 (Fig. 3),, the flat portion 30 is not subjected to any tension sufficient to injure or rupture. the metal.

From the rolls -25 the metalispassed through the rolls 32-32 (Fig. 5).. The surfaces 33-33 of the rolls 32-32 are Wider than the flat section of the cross-sectional area 29 and the distance between the surfaces 33-33 is less than the thickness of the section 30, while the angles D-D are greater than the angles C-C (Fig. 4). In consequence, the rolls 32-32, acting through the shaping surfaces 33-33, 34-34 and 35-35, will exert pressure on both the flat central section 30 and the cylindroids 3I-3l, resulting in a further lateral spread and some elongation of the metal.

The metal is formed by the rolls 32-32 into a length having the cross-sectional area indicated by the numeral 36. This area comprises a flat section 3'|, which is wider and thinner than the flat section 30, and has further flattened cylindroids 38-38 at the ends thereof. However, the cross-sectional area 36 is still almost as great as that of the original rod l0. As the shaping pressure is exerted principally upon the cylindroids 3l-3I (Fig. 4) the flat portion 31 is not subjected to any tension likely to damage the metal.

The metal is finally passed through the rolls 39-39 (Fig. 6). Here the pressure is first applied through the flat shaping surfaces 40-40 against the flattened surfaces of the cylindroids 38-38 (Fig. 5). This results in a further lateral spread of the metal together with a considerable amount of elongation until the portions 30-38 are fiattened down to the thickness of the center portion 3] when the rolls 39-39 flatten the entire body of the metal, primarily through elongation, to the final thickness desired. This produces a fiat strip having a rectangular crosssectional area designated 4| and having the width desired in the finished product. If it is desirable to reduce further the thickness of the strip, this may be accomplished by conventional methods and apparatus well known to the art. The above outlined method has been found to be especially suitable for shaping a xe' 'diameter copper rod into a strip having a final width of .980" and a final thickness of .010".

Figs. 7 to 13, inclusive, show a series of steps which may be used when it is desired to obtain a maximum amount of lateral spread with a minimum amount of elongation of any given diameter rod. For example, by using this process it is possible to obtain a strip having a final width of from about 1%" to about 1 from a 's" diameter rod without subjecting the rolled section to a. tension likely to injure it.

In accordance with this process, the angles formed by the intersection of the flat parallel middle sections and the inclined sides of the shaping surfaces of the rollsare constant in the successive spreading rolls, and the distance between the flat parallel middle sections is also substantially constant. The shaping surfaces of the rolls are so formed as to cause .a maximum of lateral spread of the metal with a minimum of elongation.

It will be obvious from an examination of Figs. 7 to 13, inclusive, that the metal is passed through successive rolls wherein a circular rodis first converted into a continuous length of metal having a dumbbell-shaped cross-section and thereafter pressure is mainly exerted upon the cylindroids at the ends of this cross-sectional area to cause a lateral spread thereof. This results in the production of an ever widening fiat central section of the metal with cylindroids of diminishing sizes at the ends thereof. The cross-sectional area of the'metal is substantially constant as it passes through successive rolls, although-:-the

cross-sectional contour is varied. The metal is finally passed through a pair of rolls having fiat shaping surf-aces, wherein lateral spread and elongation of the metal both result, to form the metal into a strip of the desired width and having a rectangular. cross-section. 4

Obviously, it may be necessary to include annealing steps in the above described processes.

The number of such steps, and the points at which they occur, will be governed by the type and size of the metal being shaped and the final size and shape desired. For instance, in the foregoing processes it may be necessary to anneal the metal after it passes through each pair of rolls, or after it passes through every second pair of rolls.

This invention is not limited to the rolling of circular rods, but may also be employed to form strips from symmetrical rods' having square, hexagonal, octagonal or other cross sections. Obviously, the number of rolls may be varied, as may also the shape and size of the roll shaping surfaces, depending on the type and size of the continuous lengths of metal to be shaped and the final size and shape desired. What is claimed is:

1. The process of forming a flat strip from a cold copper rod of circular cross-section without subjecting the metal to lateral -tension likely to injure it, which comprises subjecting such a, rod

to pressure on diametrically opposed areas to bring said areas into proximity to each other and cause a lateral spreadof the metal with a minimum of elongation, thereby forming a continuous length of metal having a flat central. portion having cylindroidal portions on the ends thereof, thereafter repeatedly exerting pressure without greatly reducing the cross-sectional areathereof, and finally exerting pressure on the fiattened cylindroids and flat central section to cause a limited amount of lateral spread and substantial elongation'thereof to form a strip of rectangular cross-sectional area.

2. The process of forming metal without subjecting the metal to a lateral tension likely to injure it, which comprises repeatedly subjecting a length of metal having a cross-sectional area formed of a flat central section with cylindroidal portions at the ends thereof to pressureapplied mainly upon the cylindroids to cause lateral spread of the metal with a minimum of elonsation, the cross-sectional area of the metal being keptapproximately constant throughout the I foregoing operations, then exerting pressure on both the cylindroids and the flat central section whereby said cylindroids are reduced in size and somewhat flattened. and said central section is reduced in thickness to cause a further lateral spread and an elongation of. the metal without 3. The process of forming a fiat strip from a rod without subjecting the metal to lateral tension. likely to injure it which comprises subjecting the rod to pressure on diametrically opposed areas to bring the areas into proximity to each other and to cause lateral spread of the metal with a minimum of elongation, thereby forming a' length of metal having a cross-sectional area substantially equal tothat of] the original rod and formed of a flat middle section having cylindroidal portions at the ends thereof.

4. The process of forming a flat strip from a ing the rod to pressure on diametrically opposed areas to bring said areas into' proximity to each other and cause a lateral spread of the metal with a minimum of elongation, thereby forming a continuous length of metal having a cross-sectional. area formed of a flat central section having cylindroid portions on the ends thereof, thereafter repeatedly exerting pressure mainly upon the cylindroids to cause a further lateral spread thereof with a minimum of elongation, the cross sectional area of the metal and the thickness of the flat central section thereof being kept ap proximately constant throughout the foregoing operations, then exerting suiilcient pressure on both the cylindroids and the flat central section to reduce the size of said 'cylindroids and some what flatten them and to reduce the thickness of said central section to cause a further lateral spread and some elongation of the metal without materially reducing the cross-sectional area thereof, and finally exerting pressure on the flattened cylindroids and iiat central section to cause a limited amount of lateral spread and substantial elongation thereof to form a strip of rectangular cross-sectional area.

'5. The process of forming metal without subjecting it to tension likely to injure it, which comprises subjecting the rod to pressure on diametrically opposed areas to bring said areas into proximity to each'other and cause a lateral spread of the metal with a minimum of elongation,

' thereby forming a continuous length of metal having a cross-sectional area formed of a flat central section having cylindroidal portions on the ends thereof, thereafter repeatedly exerting pressure mainly upon the cylindroids to causea further lateral spread thereof with a minimum of elongation, the cross-sectional area of the metal being kept approximately constant as the crosssectional shape is varied, then exerting pressure on'both the cylindroids and the flat central section whereby said cylindroids are reduced in size and somewhat flattened and said central section is reduced in thickness to cause a further lateral spread and an elongation of the metal without materially. reducing the cross-sectional area thereof, and finally exerting pressure on the fiattened cylindroids and flat central section to cause a limited amount of lateral spread and substantial elongation thereof to form a strip of rectangular cross-sectional area.

6. The process of forming metal without sub-' jecting it to tension likely to injure it, whichcomprises subjecting a length of metal having a dumbbell-shaped transverse cross-sectional area to pressure exerted mainly upon the cylindroids forming the sides'of said area to cause lateral spread of the metal with a minimum of elongation.

7. The process of forming a flat strip from a rod without subjectin the-metal to lateral tension likely to injureit, which. comprises subjecting the rod to pressure on diametrically opposed areas to bring said areas into proximity to each other and cause a lateral spread of the metal with a minimum of elongation, thereby forming a continuous length of metal having a cross-sectional area formed of a flat central section having cylindroidal portions on the ends thereof, thereafter exerting pressure mainly upon the cylin-- droids to cause a further lateral spread thereof with a minimum of elongation, the cross-sectional area of the metal being kept approximately constant as the cross-sectional shape is varied,

then exerting pressure on both the cylindroids comprises subjecting a metal rod to pressure ex- 1 erted from opposite directions principally upon a central portion of the rod to spread the metal in said central portion laterally, thereby leaving cylindroidal lobes at the sides thereof, and then applying pressure principally upon said lobes to further spread and flatten them without mates rially altering the central portion.

9. The process of forming metal strip which comprises subjecting a metal rod to pressure exerted from opposite directions principally upon a central portion of the rod to spread the metal in said central portion laterally, thereby leaving cylindroidal lobes at the sides thereof, then applying pressure principally upon said lobes to further spread and flatten them'without materially altering the central portion, the cross-sectional area of the metal being maintained substantially 10. The process of forming metal strip which lobes to further spread and flatten them without materially altering the central portion, the crosssectional area of the metal being kept approximately constant as the cross-sectional shape is varied.

11. The process of forming metal strip which comprises subjecting a metal rod to pressure on diametrically opposed areas to bring said areas into proximity to each other and cause a lateral spread of the metal with a minimum of elongation, thereby forming a continuous length of metal having a cross-sectional area formed of a flat central section having cylindroidal portions on the ends thereof, and thereafter subjecting the cylindroids to successive applications of pressure the direction of which approaches a right angle to the plane of the final strip to further spread and flatten the cylindroids.

12. The process of forming metal strip which comprises subjecting a metal rod to pressure on diametrically opposed areas to bring said areas into proximity to each other and cause a lateral spread of the metal with a minimum of elongation, thereby forming a continuous length of metal having a cross-sectional area formed of a flat central section having cylindroidal portions on the ends thereof, thereafter subjecting the cylindroids to successive applications of pressure the direction of which approaches a right,

angle to the plane of the final strip to further spread and flatten the cylindroids, and finally applying pressure upon the metal in a direction at right angles to the plane of the final strip so as to causefurther lateral spread and elongation to form a strip of rectangular cross-section.

13. The process of forming metal strip which the direction of each successive application of pressure being more nearly at a right angle to the plane of the final strip than that of the preceding application and the'cross-sectional area of the metal being kept approximately constant as the cross-sectional shape is varied.

14. The process of forming metal strip which comprises subjecting a metal rod to pressure exerted from opposite directions principally upon a central portion of the rod to'spread the metal in said central portion laterally, thereby leaving cylindroidal lobes at the sides thereof, then repeatedly applying pressure principally upon said lobes to further spread and flatten them without materially altering the central portion, the direction of each successive application of pressure being more nearly at a right angle to the plane of the final strip than that of the preceding application, and the cross-sectional area of the metal being kept approximately constant as the cross-sectional shape is varied, and finally applying pressure upon the metal in a direction at right angles to the plane of the final strip so as to cause further lateral spread and elongation 1tshereof to form a strip of rectangular cross-secion.

15. The process of forming metal strip which comprises subjecting a metal rod to pressure on diametrically opposed areas to bring said areas into proximity to each other and cause a lateral spread of the metal with a minimum of elongation, thereby forming a continuous length of metal having a p v 7 a flat central section having cylindroidal portions at the ends thereof, and thereafter subjecting the cylindroids to successive applications or pres+ sure the direction of which is constant and at a predeter ed angle strip to produce a maximum or lateral spread and a minimum of elongation of the metal, the crosssectional area of the metal and the thickness of the flat central section thereof being kept approximately constant during said forming steps. 16. The process of forming metal strip whichcomprises subjecting a metal rod of circular cross-section to pressure on diametrically opposed areas to bring said areas into proximity to each other and cause a lateral spread of the! metal with a minimum of. elongation, thereby forming a continuous length or metal having a cross-sectional area formed of a flat central section having cylindroidal portions at the ends thereof, and thereafter subjecting the cylindroids t'o successive applications of pressure the direction. of which is constant and at a predetermined of the final strip to cause a, maximum of lateral spread and a minimum of elongation of the metal, the cross-sectional area of the metal and the thickness or the flat central to'the plane of the final cross-sectional area formed of erally without subjecting it 5 section thereof being kept approximately constant during said forming steps, and finally applying pressure right angles to the plane of the final strip so as to cause further lateral spread and elongation thereof to vi'orm a strip of rectangular cross-section.

1'7. The process of spreading a metal strip latt0 tension likely to injure it, which comprises rolling longitudinally a continuous length of metal having a dumbbellshap'ed, transverse cross-sectional area, ing being applied mainly upon the cylindroids forming the sides of said length of metal to spread the length of metal laterally with a minimum of elongation.

18; The process of rolling metal strip, which comprises rolling longitudinally the diametrically op 'te portions of a metal rod to, spread the central portion or the rod laterally, thereby forming cylindroidal lobes at the sides thereof,

and then rolling the metal longitudinally principally upon the lobes to spreadand lobes without materially altering the central portion of the metal.

' HARRY BLOUNT.

CARL V. LUNDEEN.

upon the metal in a direction at the rollflatten the

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