US3630061A

US3630061A - Rolling mill apparatus and methods of rolling metal

Info

Publication number: US3630061A
Application number: US867226A
Authority: US
Inventors: Alexander Lan Wilson
Original assignee: Hille Engineering Co Ltd
Current assignee: HILLE ENGR CO Ltd; Hille Engineering Co Ltd
Priority date: 1968-10-23
Filing date: 1969-10-17
Publication date: 1971-12-28
Anticipated expiration: 1988-12-28
Also published as: FR2021378A1; BE740654A; GB1282718A; DE1952786A1

Abstract

The invention relates to a method of and apparatus for rolling metal wherein the metal is passed to and fro between the rolls of at least one pair of rolls and is gripped alternately by gripping members mounted at opposite sides of the roll pass. The metal is first gripped in a first gripping member mounted for reciprocating movement towards and away from one side of the rolls and is thus entered into the pass by movement of said gripping member towards the rolls. The metal is then received at the other side of the pass in a second gripping member mounted on that side of the pass for reciprocating movement towards or away from the rolls; the metal moves lengthwise in the direction of rolling relative to the second gripping member until free of the rolls. The metal is thereupon gripped in said second gripping member and is then reentered between the rolls (into the same or another pass) by movement of the second gripping member back towards the rolls and is again received at the first mentioned side of the rolls in the first gripping member.

Description

United States Patent lnventor Alexander Ian Wilson Sheffield, England App]. No. 867,226 Filed Oct. 17, 1969 Patented Dec. 28, I971 Assignee The Hille Engineering Company Limited Sheffield, England Priority Oct. 23, 1968 Great Britain 50,408/68 ROLLING MILL APPARATUS AND METHODS OF ROLLING METAL 22 Claims, 5 Drawing Figs.

[52] US. Cl 72/222, 72/252 [51] Int. Cl B2lb 39/14 [50] Field of Search 72/24, 252, 222, 227, 221, 250

[56] References Cited UNlTED STATES PATENTS 29,702 8/1860 Lauth 72/252 276,086 4/1883 Shaffer 72/252 Primary Examiner-Milton S. Mehr AnomeyErnest A. Greenside ABSTRACT: The invention relates to a method of and apparatus for rolling metal wherein the metal is passed to and fro between the rolls of at least one pair of rolls and is gripped alternately by gripping members mounted at opposite sides of the roll pass. The metal is first gripped in a first gripping member mounted for reciprocating movement towards and away from one side of the rolls and is thus entered into the pass by movement of said gripping member towards the rolls. The metal is then received at the other side of the pass in a second gripping member mounted on that side of the pass for reciprocating movement towards or away from the rolls; the metal moves lengthwise in the direction of rolling relative to the second gripping member until free of the rolls. The metal is thereupon gripped in said second gripping member and is then reentered between the rolls (into the same or another pass) by movement of the second gripping member back towards the rolls and is again received at the first mentioned side of the rolls in the first gripping member.

PATENIED UEB28 um SHEET 1 BF 4 PATENTED UEB28 I97! SHEET 2 OF 4 //\/l/E/\/ TOP Alexander Ian Wilson PATENTEDnEB28|97I 3630.061

SHEET U UF 4 Alexander Ian Wilson ROLLING MILL APPARATUS AND METHODS OF ROLLING METAL This invention relates to rolling mill apparatus and methods of rolling metal.

In the rolling of metal, material is fed into passes between rolls either manually or mechanically for reduction between the rolls. Manual feeding is still used extensively, particularly for rolling special steels and where size changes are frequent; a heavy, hot and unpleasant job involving a large labor force. Mechanical feeding in cases where the material leaves one pass before entering the next has involved the use of chute guides, deflector plates, cross transfer gear, skew tables, turnup devices etc., and size changing necessitates rearrangement of the guides, plates etc. which is extremely time consuming. Mechanical feeding in cases where the material enters a pass before leaving the previous pass as in continuous mills also necessitates the use of a large number of mill guides, guide troughs, repeaters etc., and accurate speed control is generally essential, thus such mills become very expensive and inflexible and can only be economically operated on large tonnages of a similar size range.

The object of the present invention is to provide improvements applicable to rolling mill apparatus and to methods of rolling, at least some of which can in some measure reduce or overcome some of the disadvantages outlined above.

According to one of its aspects the invention provides a method of rolling metal in which a first end portion of the metal is gripped in a first gripping member mounted for reciprocating movement towards and away from one side of one or more passes between rolls and is entered into a pass by movement of the first gripping member towards the pass from a rearward position, the first end portion is received at the other side of the pass in a second gripping member mounted on that side for reciprocating movement towards or away from the pass or passes, the metal moves lengthwise in the direction of rolling relative to the gripping members until its other end portion is received in the second gripping member, that other end portion is gripped in the second gripping member and is entered into the same or another pass by movement of the second gripping member back towards that pass and is again received at the first mentioned side of that pass in the first gripping member. The end portion of the material may be moved laterally by the gripping members by the action of fluid operated means when, prior to being entered into the bite of a pair of rolls having a plurality of passes spaced from each other, the material is aligned with the required one of said passes. The material may be rotated by the gripping members by the action of fluid operated turning means, for example when dealing with an oval section in course of reduction to round bar. In a preferred form of the invention, a first pair and a second pair of rolls rotate in opposite directions so that each is able to feed metal towards or away from the pass of the other, at least one roll of the second pair is retracted to an inoperative position, the second gripping member is moved to a forward position in the gap between the second pair of rolls and receives from or enters into the bite of the first pair of rolls an end portion of the metal, the second gripping member is moved to its rearward position clear of the second pair of rolls, the retracted roll or the retracted rolls of the second pair is or are returned to the operative position, at least one roll of the first pair is retracted to an inoperative position and the first gripping member is moved to its forward position in the gap between the first pair of rolls to receive from or enter into the bite of the second pair the other end portion of the metal. Where the arrangement is such that the pass line between one pair of rolls is higher than the pass line between the other pair of rolls, vertical adjustments of the gripping means may be effected between successive rolling operations. While metal is passing through the pass of one pair of rolls, the position of a nonretractable roll of the other pair may be adjusted by screw means to determine the width of the roll gap of that other pair when its retractable roll has been returned to its operative position. Preferably the movement of the gripping members to their operative positions and the adjustment of the nonretractable rolls are all effected under the control of electrical programming means.

According to another of its aspects, the invention provides rolling mill apparatus which includes at least two rolls mounted to form one or more passes, a first gripping member and a second gripping member mounted on opposite sides of the pass or passes for reciprocating movement towards and away therefrom, and clamping means for releasably clamping metal in said gripping members alternately, the arrangement being such that each gripping member is able in the course of its movement towards a pass to enter an end portion of metal into the pass and is subsequently able to receive near the pass an end portion of metal travelling therefrom. Preferably each gripping member includes a tube for receiving the metal. Each clamping means preferably includes a lever able to bear with clamping action against the metal (when present). Preferably, each clamping means also includes a fluid pressure operated piston and cylinder arrangement able to cause the lever to bear against the metal. The lever may be so shaped and i mounted that an elongate part of it can bear against the metalto constrain it against a corresponding length of the tube. A sensing device is preferably provided to sense entry of the metal into each gripping means and is operatively connected to cause the lever to be applied with light pressure against the a metal (when present) to quickly decelerate the bar when the trailing end of the bar has passed between the rolls. The gripping means may however be provided with a pair of pinch rolls for driving out a leading end of a bar which the clamping means have failed to arrest as the gripping means have received said material from a pass. The gripping members may be mounted upon carriages arranged for movement towards and away from the pass or passes under the action of fluid pressure. Preferably the carriages are also arranged for lateral movement. The gripping members may be mounted for rotational movement about a longitudinal axis thereof. Desirably a load sensitive device is provided to sense when a pair of rolls ceases to be under load consequent upon the metal having left that pair of rolls and is operatively connected to cause the respective gripping member to move away from the bite by a predetermined distance to a rearward position. In a preferred embodiment of the invention, two pairs of rolls are mounted so that each pair is able to feed metal towards the bite of the other, and at least one roll of each pair is retractable from an operative position to an inoperative position, the arrangement being such that each gripping member is able when the retractable roll or rolls of a pair of rolls has been retracted to extend through the gap between those rolls to a forward position near the bite of the other pair of rolls. Means may be provided for effecting vertical adjustments of the gripping means between successive rolling operations to compensate for the pass line between one pair of rolls being higher than the pass line between the other pair of rolls. Abutments may be provided to determine the operative positions of the retractable rolls. Preferably a nonretractable roll of each pair has screw means associated with it able to determine the gap between the rolls when the retractable roll is in its operative position. Preferably electrical programming means are operatively connected to control the retraction of the retractable rolls, the adjustment of the nonretractable rolls and the movement of the gripping members.

In order that the invention may be clearly understood and readily carried into effect a preferred embodiment thereof will now be described, by way of example only, with reference to the accompanying drawings in which:

FIG. I is a diagrammatic general arrangement drawing of rolling mill apparatus;

FIG. 2 is a side elevation, partly in section, of roll stands and manipulators forming part of the apparatus, as seen along the line IIII of FIG. 3;

FIG. 3 is a top plan, partly in section as seen along the line lll-lll of FIG. 2;

FIG. 4 is a sectional view taken on the line IV--IV in FIG. 2,

and the retraction of the retractable rolls from and their return and FIG. 5 shows the roll stands in greater detail in part sectional side elevation.

Turning to the drawings, there is shown rolling mill apparatus having roll stands in housings l0 and 12, integral to form a double-duo housing. The housing carries a first pair of

rolls

14 and 16. The lower roll 14 is retractable by a hydraulic ram 18 from its operative position (see FIGS. 1 and 2) to an inoperative position shown in broken lines. The housing 12 carries a second pair of

rolls

20 and 22. Here the upper roll 20 is retractable to an inoperative position from an operative position shown in broken lines. The retractable rolls l4 and 20 are carried by chairs 24 (see FIG. 5) slidable in windows 25 of the housings and their operative positions are determined by abutments in the form of shoulders 26 against which the chairs are held by hydraulic pressure when the rolls are moved to their operative positions by the rams 18. The position of the

nonretractable rolls

16 and 22 is adjustable by screws 28 driven by electric motors 30 to vary the roll gap. (It will be seen that in this particular arrangement the pass line is not constant, but for each pair of rolls varies in accordance with the roll gap setting. In addition, the pass line between the

rolls

14 and 16 is higher than the pass line between the

rolls

20 and 22 to ensure adequate clearance of the nonretractable roll of the inoperative pair of rolls at each pass). Load sensing devices 32 associated with each pair of rolls (FIG. 1) can signal when metal passing between the rolls has left the bite between them. A motor 33 is drivingly connected to the rolls. The rolls have conventional side-by-side box passes, oval passes and round passes for reducing metal bar.

Manipulators include a first gripping member generally designated 34 disposed to one side namely to the left of the bite formed between the pair of rolls in the housing 10, and a second gripping member 36 disposed to the right of the housing 12. Each gripping member includes a tube 38 (see FIGS. 1 to 3), clamping means in the form of a lever 40, a pneumatic piston and cylinder arrangement 42 for actuating the lever 40, a pneumatic ram 44 for imparting reciprocating movement to the tube towards and away from the rolls, a hydraulic ram 46 for imparting transverse movement to the tube, a pneumatically actuated turning device 48 for imparting rotation to the tube and sensing means 50 to signal the arrival in the tube of metal from the adjoining rolls. Electrical programming means 52 is operatively connected to the several parts. The leading end of the tube 38 can be brought to any one of 3 positions of rest by the pneumatic ram 44, namely a rearward position indicated (a), a normal or intermediate position (b) and a forward position (c).

Turning more particularly to FIGS. 2 and 3, the tube 38 of each gripping member has an outwardly flared nose 54 at its open end and an opening 56 in its side. The lever 40 is mounted upon a pivot 58; it has an elongate part 60 extending into the tube through the opening 56 and a stub part 62 which can be acted upon by the pneumatic piston 42 (not shown in FIGS. 2 and 3) to urge elongate part 60 towards the inner side of the tube remote from the opening 56. The tube 38 is mounted on a carriage in the form of a trolley 64. The pneumatic ram 44 is mounted on the trolley to move the tube along a runway 66 towards and away from the bite of the rolls. Hydraulic ram 46 is mounted to traverse the trolley along a track 68 on which it is supported by a wheel 70 and along a guide 72, whereby the tube 38 can be made to move transversely of the rolls. The tube 38 is rotatably mounted in bearings 74 by way of bushes 76 and can be rotated by the rotating device 48 comprising pneumatic ram 78 and linkage 80.

Means including hydraulic cylinders 82 are provided for adjusting the vertical height of the leading end of each tube 38 between successive rolling operations to compensate for the pass line between

rolls

14 and 16 being higher than the pass line between

rolls

20 and 22. When vertical adjustments are made, the gripping members and trolleys on which they are mounted move bodily about the points on the tracks 68 where the wheels 70 are resting.

Operation of the apparatus while reducing metal bar at the stage of rolling to oval sections is as follows. The leading end of the tube 38 of the left hand gripping member 34 will initially be in its retracted position (a) (not shown in the drawings) holding the right-hand end portion of a bar 82 with the end of the bar protruding forwardly and the main length of the bar trailing rearwardly. Retractable roll 14 in left-hand housing 10 will be in its operative position and nonretractable roll 16 will be at a correct setting ready for rolling the bar through a selected oval pass in the rolls. Retractable roll 20 in the right-hand housing will be in its retracted position. The leading end of the tube 38 of the right-hand gripping member 36 will be in its forward position (i c) extending between the rolls of the right hand housing to near the bite of the left-hand housing. The tubes 38 will both be in the transverse position corresponding to the selected pass and will thus be both aligned with that pass and with each other. Lever 40 of the left hand gripping member 34 will be actuated firmly to grip the bar 82 and the lever of right-hand gripping member 36 will not be actuated so as to lie close to opening 56 through which it projects. The left hand gripping member will be oriented to present the bar with the major axis of its oval section vertical and thus its lever 40 will be pressed against the bar from the side. The right-hand gripping member will be oriented to receive the bar with the major axis of its section horizontal so that lever 40 can press against the bar from below (see FIG. 2). The rolls are kept in constant rotation by motor 33 in opposite directions so that each pair of rolls 14-16 and 20-22 can in turn feed the bar in the direction of the other pair.

Programmer 52 delivers an electrical signal to actuate pneumatic ram 44 of left-hand gripping member 34 which moves tube 38 to bring its leading end to the normal position (b) (see FIG. 2) thereby entering the protruding end of the bar into the selected pass between the left-hand pair of rolls. Load sensing device 32 of the left-hand pair of rolls delivers a signal to the programmer which in turn delivers a signal to deactivate pneumatic piston 40 of the left-hand gripping member to release the bar. The end portion of the bar is reduced in the oval pass and is received in the aligned tube 38 at the right-hand side of the bite, being guided by flared nose 54 of that tube. Sensing means 50 detects the arrival of the bar in the tube, causing a signal to be delivered by way of the programmer to its associated pneumatic piston 42 to cause it to apply the lever with light pressure against the metal; the metal being constrained by the elongate part of the lever against a corresponding length at the side of the tube is thereby quickly decelerated when the trailing end of the bar has passed between the

rolls

14, 16 and throw out" is eliminated or reduced. (If desired, a pair of pinch rolls 39 may be provided some distance rearwardly of the leading end of each tube as shown in chaindotted lines in FIGS. 2 and 3, said rolls being drivable by means not shown and adjustable towards and away from each other as indicated by the arrows in FIG. 3. If throwout of material should occur, that is to say if the trailing end of the material should slip past the elongate part 60 of the lower 40 into the tube, the pinch rolls will then be used to drive it out again).

As rolling progresses, the programmer delivers a signal to the motor 30 associated with the nonretractable roll of the right-hand housing to adjust its setting in readiness for the next rolling operation; since this adjustment takes place while the other pair is operative, the adjustment can be effected slowly and accurately without hold up of the mill (e.g., by the use of a slow thread screw and slow moving motor).

When the whole length of the bar has been reduced in the selected pass, its left-hand end will have been drawn from the tube of the left-hand gripping member so that the left-hand end portion is held in the tube of the right-hand gripping member and the load sensing device 32 of the left-hand pair of rolls will have signalled to the programmer that the bar is no longer in the bite. Thereupon the programmer delivers signals for several steps to take place, namely for pneumatic piston 42 of the right-hand gripping member to cause its lever firmly to grip the bar, for pneumatic ram 44 to move the right-hand tube to the right from out of the gap between the right-hand rolls so that its leading end assumes the rearward position (a), for the hydraulic rams 18 to retract left-hand retractable roll 14 from its operative position and to move right-hand retractable roll 20 to its operative position (and to hold it there), for the hydraulic rams 46 to move the trolleys 64 transversely into alignment with the next selected pass (it is assumed that this is not in alignment with the previous selected pass), for the pneumatic rams 78 to cause their respective turning devices 48 to be rotated through 90 by way of their linkages 80, for the pneumatic ram 44 of the left-hand gripping member to move its tube to its forward position (c), for the leading ends of the tubes to be vertically adjusted and, finally, for the pneumatic ram 44 of the right-hand gripping member to move to its normal position (b) thereby entering the left-hand end of the bar into the bite between the righthand rolls for the process to be repeated.

The bar is rolled in the mill, being reversed to and fro, from end to end and from pass to pass until the reduction has been completed. The rolling program and the operation of the manipulators is wholly automatic, being preset upon for example punched card fed into the programmer.

The apparatus described above has many advantages quite apart from automaticity. Some of the material is always contained in one or other of the gripping members and is not at any time completely let loose. The constraint applied by the levers 40 during rolling assists in maintaining the bar straight. The bar is afforded straight entry into the rolls and supported run out from the rolls and does not require lifting through large distances. Cross transfer is through comparatively small distances as one pair of rolls is directly behind the other and indeed in some reduction sequences cross transfer is at times avoided altogether where the pass in one pair of rolls for the forward journey is in line with the pass in the other pair of rolls for the return journey. Different reduction sequences can be set up upon punched cards and then it is possible for many applications to change the reduction sequence by the mere change of a punched card in the programming device.

it will be appreciated that many modifications can be made in the apparatus described above without departing from the scope of the invention. For example the manipulators can be used with rolling mills of different configurations, for example with reversing two-high mills (where the gripping members will move only between their normal and their rearward positions), side-by-side two-high mills (where the gripping members will be traversed from one to the other between consecutive passes), and three-high mills (where a device for lifting and lowering the gripping members bodily would have to be provided). It will in fact be preferable for both rolls of a twohigh mill, or for both rolls of each stand of a double-duo arrangement, to be retractable simultaneously and through equal distances so that the pass line is kept constant, roll gap adjustments being made in any convenient manner. In this way it will be unnecessary for the gripping members to be vertically adjustable. It is envisaged that the gripping members will be used in conjunction with simplified feed forms of stripper and entry guide particularly for rolling comparatively thin or light materials. The manipulator movements and also the rolling program could be controlled manually, in a semiautomatic mill, for example by operation of electrical controls from an adjoining desk. The load sensing devices 32 could be replaced by photoelectric cells for giving an electrical signal when the end of a length of material has passed through one or other of the pair of rolls.

What I claim and desire to secure by Letters Patent is:

l. A method of rolling metal, comprising gripping a first end portion of the metal for movement relative to a pass between rolls, entering the gripped metal into the pass by a first reciproeable gripping member for the metal when the gripping member is moved toward the pass from a rearward position, receiving the first end portion of the metal at the other side of the pass in a second gripping member mounted on said other side for reciprocating movement towards and away from the pass, moving the metal lengthwise in the direction of rolling relative to the gripping members until its other end portion is received in the second gripping member, gripping said other end portion in the second gripping member, and reentering said gripped other end portion between the rolls by movement of the second gripping member back towards the rolls for reception of said metal at the first mentioned side of the pass by the first gripping member.

2. The method according to claim 1, characterized by moving the end portion of the metal laterally by the gripping mem bers by the action of fluid operated means, when, prior to being entered into the bite of a pair of rolls having a plurality of passes spaced from each other, the metal is aligned with the required one of said passes.

3. The method according to claim 1, characterized by rotating the gripping members by the action of fluid operated turning means.

4. The method according to claim 1, characterized by rotating a first pair and a second pair of rolls in opposite directions so that each is able to feed said metal towards and away from the pass of the other, retracting at least one roll of the second pair to an inoperative position, moving the second gripping member to a forward position in a gap between the second pair of rolls and alternately receiving from and entering into the bite of the first pair of rolls an end portion of the metal, moving the second gripping member to its rearward position clear of the second pair of rolls, returning the retracted roll of the second pair to its operative position, retracting at least one roll of the first pair to an inoperative position, and moving the first gripping member to its forward position in the gap between the first pair of rolls to alternately receive from and enter into the bite of the second pair the other end portion of the metal.

5. The method according to claim 4, characterized by vertically adjusting the gripping members between successive rolling operations to compensate for the pass line between one pair of rolls being higher than the pass line between the other pair of rolls.

6. The method according to claim 4, characterized by adjusting, while metal is passing through the pass of one pair of rolls, the position of a nonretractable roll of the other pair to determine the width of the roll gap of that other pair when its retractable roll has been returned to its operative position.

7. The method according to claim 4, characterized by the movement of the gripping members and the retraction of the retractable rolls from and their return to their operative positions and the adjustment of the nonretractable rolls are all effected automatically.

8. Rolling mill apparatus including at least two rolls mounted to form at least one pass, a first gripping member and a second gripping member mounted on opposite sides of the pass for reciprocating movement towards and away therefrom, clamping means for each gripping member adapted to releasably clamp metal in said gripping members alternately, and means for moving at least one of said gripping members independently of the other gripping member, said one of said gripping members being adapted upon movement thereof to enter an end portion of metal into the pass and subsequently to receive near the pass an end portion of metal travelling therefrom.

9. Apparatus according to claim 8, wherein each gripping member includes a tube for receiving the metal.

10. Apparatus according to claim 8, wherein each clamping means also includes includes a lever.

11. Apparatus according to claim 10, wherein each clamping means also includes a fluid pressure operated piston and cylinder arrangement for operating the lever.

12. Apparatus according to claim 10, wherein the lever has an elongate part which bears against metal adapted to be gripped by the associated gripping member to constrain the metal against a corresponding length of the member.

13. Apparatus according to claim 10, wherein a sensing device is provided to sense entry of the metal into each gripping member.

14. Apparatus according to claim 8, wherein each gripping member is provided with a pair of pinch rolls for driving out a leading end of a length of material which the clamping means have failed to arrest as the gripping members have received said material from a pass.

15. Apparatus according to claim 8, including carriages on which the gripping members are mounted for movement towards and away from the pass under the action of fluid pressure.

16. Apparatus according to claim 15, wherein the carriages are also mounted for lateral movement.

17. Apparatus according to claim 8, wherein the gripping members are mounted for rotational movement about a longitudinal axis thereof.

18. Apparatus according to claim 8, wherein a load sensitive device is provided to sense when a pair of rolls ceases to be under load consequent upon the metal having left that pair of rolls.

19. Apparatus according to claim 8, including two pairs of rolls and driving means therefore for feeding metal between either pair of rolls in the direction of the other, at least one roll of each pair of rolls being retractable from an operative position to an inoperative position, the gripping members being mounted to extend through the gap between the adjacent inoperative pair of rolls to a forward position near the bite of the other pair of rolls.

20. Apparatus according to claim 19, wherein means are provided for effecting vertical adjustments of the gripping members between successive rolling operations to compensate for the pass line between one pair of rolls being higher than the pass line between the other pair of rolls.

21. Apparatus according to claim 19, wherein abutments are provided to determine the operative positions of the retractable rolls.

22. Apparatus according to claim 19, including screw means associated with a nonretractable roll of each pair of rolls for determining the gap between the rolls when the retractable roll is in its operative position.

Claims

1. A method of rolling metal, comprising gripping a first end portion of the metal for movement relative to a pass between rolls, entering the gripped metal into the pass by a first reciprocable gripping member for the metal when the gripping member is moved toward the pass from a rearward position, receiving the first end portion of the metal at the other side of the pass in a second gripping member mounted on said other side for reciprocating movement towards and away from the pass, moving the metal lengthwise in the direction of rolling relative to the gripping members until its other end portion is received in the second gripping member, gripping said other end portion in the second gripping member, and reentering said gripped other end portion between the rolls by movement of the second gripping member back towards the rolls for reception of said metal at the first mentioned side of the pass by the first gripping member.

2. The method according to claim 1, characterized by moving the end portion of the metal laterally by the gripping members by the action of flUid operated means, when, prior to being entered into the bite of a pair of rolls having a plurality of passes spaced from each other, the metal is aligned with the required one of said passes.