GB2094684A - Rolling mills - Google Patents
Rolling mills Download PDFInfo
- Publication number
- GB2094684A GB2094684A GB8108413A GB8108413A GB2094684A GB 2094684 A GB2094684 A GB 2094684A GB 8108413 A GB8108413 A GB 8108413A GB 8108413 A GB8108413 A GB 8108413A GB 2094684 A GB2094684 A GB 2094684A
- Authority
- GB
- United Kingdom
- Prior art keywords
- rails
- bearing boxes
- rolls
- rolling mill
- roll
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B31/00—Rolling stand structures; Mounting, adjusting, or interchanging rolls, roll mountings, or stand frames
- B21B31/08—Interchanging rolls, roll mountings, or stand frames, e.g. using C-hooks; Replacing roll chocks on roll shafts
- B21B31/10—Interchanging rolls, roll mountings, or stand frames, e.g. using C-hooks; Replacing roll chocks on roll shafts by horizontally displacing, i.e. horizontal roll changing
- B21B31/106—Vertical displacement of rolls or roll chocks during horizontal roll changing
Abstract
A four-high rolling mill has backup chocks 7 & 8 which partially surround the chocks 3, 4 of the working rolls, and two rails 9 which extend beneath the lower chocks 4. Four piston/cylinder units 11 extend between the chocks 8, 7 of the lower and upper backup rolls. When the units are extended the bearing boxes 7 of the upper backup roll are lifted and this motion is transmitted via links 12 to the rails 9 which are also lifted. The rails engage wheels 14 mounted on rods 15 and thus lift them and the two working rolls 1 and 2. The two working rolls are then removed longitudinally on the rails 9 and can be replaced by new ones. <IMAGE>
Description
SPECIFICATION
Rolling mills
The present invention relates to rolling mills and is concerned with an apparatus and method for replacing the upper and lower working rolls of a rolling mill.
In rolling mills, especially four-high rolling mills, of the type in which bearing boxes for an upper working roll are embraced, that is to say at least partially surrounded, by bearing boxes for an upper backup roll while bearing boxesfora lower working roll are embraced by bearing boxes for a lower backup roll replacement of the upper and lower working rolls is periodically required. In one known method for simultaneously replacing both the upper and lower working rolls, a double-eyed porter bar is engaged with one end of the roll shafts and then the rolls and their bearing boxes are lifted out from the rolling mill by a crane while balance is maintained between the roll assembly and the counterweight of the porter bar. A new roll is mounted in the rolling mill in the reverse order.In another known method, a double-eyed porter bar is engaged with one end of the roll shafts so that the rolls and their bearing boxes may be supported like cantilever. In yet a further known method, bearing boxes for a lower backup roll are mounted on a truck and after the bearing boxes for the upper and lower working rolls have been mounted in the bracing portions of the bearing boxes for the lower backup roll, the truck is pulled out of the rolling mill. New working rolls are mounted on the rolling mill in the reverse order.
According to the present invention a rolling mill includes upper and lower working rolls and upper and lower backup rolls each mounted in respective bearing boxes and further includes a pair of rails extending between the bearing boxes of the lower bearing roll and substantially parallel to the axis of the latter, first lifting means adapted to lift the bearing boxes ofthe upper backup roll, second lifting means adapted to lift the pair of rails from a lower position to an upper position and third lifting means adapted to lift the bearing boxes of the upper and lower working rolls whereby, in use, afterthe rails and the bearing boxes of the upper backup roll and the upper and lower working rolls have been lifted the working rolls may be removed on the rails and new working rolls may be placed in position.
Preferably the bearing boxes of the upper and lower working rolls are at least partially surrounded by those of the upper and lower backup rolls respectively. The rolling mill conveniently includes at least one stop positioned to be engaged by the bearing boxes of the upper backup roll to retain the latter in the required working roll replacement position, and the first lifting means conveniently includes a plurality of piston/cylinder units.
In one embodiment of the invention the second lifting means comprises a plurality of links each adapted to engage one of the rails and connected to the first lifting means whereby the first lifting means lifts the bearing boxes of the upper backup rolls and the rails to their upper position. In another embodiment the second lifting means comprise a plurality of piston cylinder units whose piston rods engage one of the rails. In the latter case there may be a plurality of rods each of which engages one of the rails and the underside of one of the bearing boxes of the upper backup roll.
The preferred embodiment includes a plurality of elongate force transmitting elements whose lower ends are positioned to be engaged and thus lifted by the rails when the latter are lifted and which are arranged to lift the bearing boxes of the upper and lower working rolls thereby constituting the third lifting means. Preferably each force transmitting element carries a wheel at its lower end adapted to engage and to run along one or other of the tracks.
Conveniently each force transmitting element extends through, and is capable of limited sliding movement with respect to one of the bearing boxes of the lower working roll and its upper end is adapted to engage and thereby to lift one of the bearing boxes of the upper working roll.
The rolling mill preferably also includes a pair of rails adjacent the rolling mill positioned so that they are aligned with the pair of rails on the rolling mill when the latter rails are lifted to their upper position.
A truck may thus run along these tracks removing worn working rolls fromthe rolling mill or inserting new ones.
The invention also embraces a method of replacing the upper and lower working rolls of a rolling mill having upper and lower working rolls and upper and lower backup rolls, each supported by two respective bearing boxes which includes the steps of lifting a pair of rails which extend between the bearing boxes of the lower working roll and parallel to the axis of the latter from a lower position to an upper position, lifting the bearing boxes of the upper backup rolls, lifting the bearing boxes of the upper and lower working rolls and then removing the working rolls laterally on the rails and positioning two fresh working rolls also on the rails.
Thus when the working rolls are to be replaced their bearing boxes are mounted or placed on the rails and they are both withdrawn laterally from the rolling mill. New rolls are inserted by reversing the removal sequence. During this operation the working and backup rolls are maintained spaced apart by a predetermined distance.
Further features and details of the present invention will be more apparent from the following description of two preferred embodiments which is given by way of example with reference to the accompanying diagrammatic drawings, in which Figure 1 is a front elevation of a four-high rolling mill equipped with a device in accordance with the present invention from which various components have been omitted for the sake of clarity;
Figure 2 is a side elevation of the rolling mill shown in Figure 1;
Figure 3 is a view seen in the direction indicated by the arrow A in Figure 1; and
Figure 4 is a scrap elevation of another embodiment of the present invention.
The four-high rolling mill seen in Figures 1 to 3 includes upper and lower working rolls 1 and 2 mounted in respective bearing boxes 3 and 4 and upper and lower backup rolls 5 and 6 mounted in respective bearing boxes 7 and 8. The bearing boxes 3 of the upper working roll 1 are embraced by the bearing boxes 7 of the upper backup roll 5 while the bearing boxes 4 of the lower working roll 2 are embraced by the bearing boxes 8 of the lower backup roll 6. A pair of rails 9 for replacement of the working rolls 1 and 2 extend transversely of the rolling mill, i.e. parallel to the roller axes, on opposite sides of the roll 2 and bearing boxes 4 for the lower working roll 2 and those portions of the bearing boxes 8 for the lower backup roll 6 which embrace the bearing boxes 4.As best seen in Figure 3, a projection 10 extends laterally outwardly from a position spaced by a predetermined distance from each end of each rail 9. On each side of the rolling mill a pneumatic or hydraulic cylinder 11 for balancing the backup rolls 5 and 6 is disposed between the upper and lower bearing boxes 7 and 8. Associated with each cylinxder 11 is a link comprising an
L-shaped lever 12, which has a lower arm adapted to engage with the projection 10, and whose upper end is connected to the upper or free end of the piston rod of the cylinder 11. Therefore when the cylinders 11 are actuated to extend their piston rods, the upper bearing boxes 7 are lifted and simultaneously the
L-shaped levers 12 are brought into engagement with their corresponding projections 10 extending from the rails 9 so that the rails 9 are also lifted.Thus the cylinders 11 serve not only to balance the backup rolls 5 and 6 but also to lift the rails 9. The length of the L-shaped levers 12 is so chosen that when the tops of the upper bearing boxes 7 come into engagement with suitably positioned stops 13 extending from the rolling mill housing so that they are maintained in the required working roll replacement position, the rails 9 are lifted by a predetermined distance so that they are correctly aligned with a pair of rails laid beside the rolling mill for replacement of the working rolls 1 and 2.
On each side of the rolling mill, two elongate force transmitting element comprising rods 15 carrying a wheel 14 at their lower ends extend through the lower bearing box 4 for sliding movement therethrough. The wheels 14 are aligned with the rails 9 and only limited relative vertical movement is permitted between the rods 15 and the lower bearing boxes 4. Thus when the rails 9 are lifted in the manner described above, the wheels 14 and rods 15 are also lifted with the result that the upper ends of the rods 15 push up the bearing boxes 3 for the upper working roll and the bearing boxes 4 are also lifted by a certain distance, thereby leaving a predetermined spacing between the upper and lower working rolls 1 and 2. The bearing boxes 4 may be lifted by any convenient means, e.g. engagement of the brackets carrying the wheels 14 with the underside of the bearing boxes 4.
The rolling mill also includes cylinders 16for balancing the bearing boxes 3 and 4forthe upper and lower working rolls 1 and 2 and an adjustment or reduction screw 17.
The rolling mill is shown as being already set to the required position for replacing the upper and lower working rolls 1 and 2. In order to carry out working roll replacement, the reduction screw 17 is lifted or spacers are retracted. Next the cylinders 11 are actuated to extend their piston rods until the upper bearing boxes 7 are brought into abutment with the stops 13. The L-shaped levers 12, whose upper ends are connected to the free ends of the piston rods of the cylinders 11, are also lifted so that their lower arms engage the associated projections 10 extending from the rails 9, whereby the rails 9 are also lifted and aligned with the pair of rails exterior of the rolling mill as described previously.When the rails 9 are lifted, they are brought into engagement with the wheels 14 at the lower ends of the rods 15 extending through the bearing boxes 4forthe lower working roll 2 so that the bearing boxes 3 and 4 are slightly lifted. As a result, a spacing required for replacement of the working rolls 1 and 2 is left between the working roll 2 and the backup roll 6.
In this first embodiment, the cylinders 11 are used not only for balancing between the backup rolls 5 and 6 but also for lifting the rails 9 as described previously. In a second embodiment shown in
Figure 4, a rod 18, guided by guides 19 for vertical movement, is adapted to ride on the upper surface of each projection 10 extending from the rails 9.
Cylinders 20 are mounted on the lower bearing boxes 8 for lifting the projections. When the cylinders 11 are actuated so that the upper bearing boxes 7 are lifted and then maintained by the stops 13 in the working roll replacement position, the cylinders 20 are extended so that the rails 9 are lifted and located at the predetermined position as the upper end of the rod 18 engages the bottom of the upper bearing box 7. In a further modification of the present invention, in addition to the cylinders 11, cylinders (not shown) are provided, to the piston rods of which the upper ends of the L-shaped levers 12 are connected, so that when the cylinders are actuated, the L-shaped levers 12 directly lift the rails 9.
In the first embodiment shown in Figures 1 to 3, the rails 9 extend transversely through the rolling mill between the bearing boxes 4 and those portions of the bearing boxes 8 which embrace the bearing boxes 4 for the lower working rolls 2. When the rails 9 are lifted in the manner described above, they may be easily connected to the exterior rails along which a truck runs for replacing the working rolls (removing the old working rolls and providing new working rolls). However, in some four-high rolling mills sufficient space is not available for making the rails 9 as long as illustrated in Figure 1. In this case, the rails 9 may extend a distance substantially equal to the length of the working rolls. The exterior rails are so laid that when the rails on the rolling mill are lifted in a manner substantially similar to that described above, the exterior rails may be inserted betwen the bearing box 4 for the lower working roll 2 and the bearing box 8 for the lower backup roll 6 on one side (working side) of the rolling mill and connected to the rails on the rolling mill. Thus replacement of the upper and lowerworking rolls 1 and 2 may be easily carried out in a manner substantially similar to that described above.
Thus, in summary, in the present invention, the lifting cylinders 11 are so arranged that when the upper ends of the rods 15 or 18 are brought into engagement with the bottom of the bearing boxes 7 for the upper backup roll 5, the rails 9 are lifted to and maintained at a predetermined height. Thus a connection or alignment between the rails 9 on the rolling mill and the exterior rails can be accomplished in a very simple manner for the replacement of the upper and lowerworking rolls 1 and 2. In addition, when the rails 9 are lifted, the bearing boxes 3 for the upper working roll 1 are also lifted away from the bearing boxes 4 and maintained at a predetermined spacing therefrom. As a result, the upper and lower working rolls 1 and 2 are spaced apart from each otherfortheir replacement. Thus with the aid of the present invention the time required for the replacement of the upper and lower working rolls can be drastically reduced and consequently the operational efficiency of a rolling mill can be considerably improved.
Claims (21)
1. A rolling mill including upper and lower working rolls and upper and lower backup rolls each mounted in respective bearing boxes and further including a pair of rails extending between the bearing boxes of the lower bearing roll and substantially parallel to the axis of the latter, first lifting means adapted to lift the bearing boxes of the upper backup roll, second lifting means adapted to lift the pair of rails from a lower position to an upper position and third lifting means adapted to lift the bearing boxes of the upper and lower working rolls whereby, in use, after the rails and the bearing boxes of the upper backup roll and the upper and lower working rolls have been lifted the working rolls may be removed on the rails and new working rolls may be placed in position.
2. A rolling mill as claimed in claim 1 in which the bearing boxes of the upper and lower working rolls are at least partially surrounded by those of the upper and lower backup rolls respectively.
3. A rolling mill as claimed in claim 1 or claim 2 includng at least one stop positioned to be engaged by the bearing boxes of the upper backup roll to retain the latter in the required working roll replacement position.
4. A rolling mill as claimed in any one of claims 1 to 3 in which the first lifting means includes a plurality of piston/cylinder units.
5. A rolling mill as claimed in any one of the preceding claims in which the second lifting means comprises a plurality of links each adapted to engage one of the rails and connected to the first lifting means whereby the first lifting means lifts the bearing boxes of the upper backup rolls and the rails to their upper position.
6. A rolling mill as claimed in any one of claims 1 to 4 in which the second lifting means comprise a plurality of piston cylinder units whose piston rods engage one of the rails.
7. A rolling mill as claimed in claim 6 including a plurality of rods each of which engages one of the rails and the underside of one of the bearing boxes of the upper backup roll.
8. A rolling mill as claimed in any one of the preceding claims in which the first lifting means are mounted on and act against the bearing boxes of the lower backup rolls.
New claims filed on 9.10.81.
Superseded claims 1 to 8.
New or amended claims:
As on new pages 10,11 claims 1 to 7.
1. Arolling mill including upper and lower working rolls and uper and lower backup rolls each mounted in respective bearing boxes and further including a pair of rails extending between the bearing boxes of the lower bearing roll and substantially parallel to the axis of the latter, first lifting means mounted on the bearing boxes of the lower backup roll and adapted to bear against the latter and lift the bearing boxes of the upper backup roll, second lifting means adapted to lift the pair of rails from a lower position to an upper position, third lifting means adapted to lift the bearing boxes of the upper and lower working rolls and at least one stop positioned above the bearing boxes of the upper backup roll whereby, in use, the rails and the bearing boxes of the upper backup roll and the upper and lower working rolls are lifted until the bearing boxes of the backup roll engage the stop whereafter the working rolls may be removed on the rails and new working rolls may be placed in position.
2. A rolling mill as claimed in Claim 1 in which the bearing boxes of the upper and lower working rolls are at least partially surrounded by those of the upper and lower backup rolls respectively.
3. A rolling mill as claimed in Claim 1 or Claim 2 in which the first lifting means includes a plurality of piston/cylinder units.
4. A rolling mill as claimed in any one of the preceding claims in which the second lifting means comprises a plurality of links each adapted to engage one of the rails and connected to the first lifting means whereby the first lifting means lifts the bearing boxes of the upper backup rolls and the rails to their upper position.
5. A rolling mill as claimed in any one of Claims 1 to 3 in which the second lifting means comprises a plurality of piston cylinder units whose piston rods engage one of the rails.
6. A rolling mill as claimed in Claim 5 including a plurality of rods each of which engages one of the rails and the underside of one of the bearing boxes of the upper backup roll.
7. A rolling mill as claimed in any one of the preceding claims in which the first lifting means are mounted on and act against the bearing boxes of the lower backup rolls.
9. A rolling mill as claimed in any one of the preceding claims including a plurality of elongate force transmitting elements whose lower ends are positioned to be engaged and thus lifted by the rails when the latter are lifted and which are arranged to lift the bearing boxes of the upper and lower working rolls thereby constituting the third lifting means.
10. A rolling mill as claimed in claim 9, in which each force transmitting element carries a wheel at its lower end adapted to engage and to run along one or other of the tracks.
11. A rolling mill as claimed in claim 9 or claim 10 in which each force transmitting element extends through, and is capable of limited sliding movement with respect to, one of the bearing boxes of the lower working roll and its upper end is adapted to engage and thereby to lift one of the bearing boxes of the upper working roll.
12. A rolling mill as claimed in any one of the preceding claims including a pair of rails adjacent the rolling mill positioned so that they are aligned with the pair of rails on the rolling mill when the latter rails are lifted to their upper position.
13. A rolling mill substantially as specifically herein described with reference to Figures 1 to 3 of the accompanying drawings either alone or modified as shown in Figure 4.
14. A method of replacing the upper and lower working rolls of a rolling mill having upper and lower working rolls and upper and lower backup rolls, each supported by two respective bearing boxes which includes the steps of lifting a pair of rails which extend between the bearing boxes of the lower working roll and parallel to the axis of the latter from a lower position to an upper position, lifting the bearing boxes of the upper backup rolls, lifting the bearing boxes of the upper and lower working rolls and then removing the working rolls laterally on the rails and positioning two fresh working rolls also on the rails.
15. A method as claimed in claim 14 which includes actuating a single set of piston/cylinder units which act directly or indirectly on the bearing boxes of the upper backup rolls, the pair of rails and the bearing boxes of the upper and lower working rolls.
16. A method or replacing the upper and lower working rolls of a rolling mill substantially as specifically described herein with reference to Figures 1 to 3 of the accompanying drawings either alone or modified as shown in Figure 4.
17. In a four-high rolling mill of the type in which bearing boxes for an upper working roll are embraced by bearing boxes for an upper backup roll respectively and bearing boxes for a lower working roll are embraced by bearing boxes for a lower backup roll respectively, a device for replacing the upper and lower rolls comprising a pair of rails extended in parallel with axes of the working and backup rolls between bottoms of the bearing boxes for the lower working roll and portions of the bearing boxes for the lower backup roll which embrace the bearing boxes for the lower working roll, cylinder means mounted on the bearing boxes for the lower backup roll and adapted to lift the bearing boxes for the upper backup roll, first lifting means for said pair of rails, second lifting means adapted to be lifted in unison with said pair of rails so as to engage with the bearing boxes for the upper working roll, thereby pushing upward the same, and stop means extended from a housing for engagement with the bearing boxes for the upper backup roll so as to maintain the same in working roll replacement position.
18. Adeviceforreplacing upper and lower working rolls as set forth in claim 17 wherein each of said first lifting means comprises an L-shaped lever one end of which is adapted to engage with one of said pair of rails and the other end of which is connected to the free end of the piston rod of each of said cylinder means, whereby said cylinder means can be used not only for lifting the bearing boxes for the upper backup roll to working roll replacement position but also for lifting said pair of rails to working roll replacement position.
19. Adeviceforreplacing upper and lower working rolls as set forth in claim 17 wherein each of said first lifting means comprises a cylinder whose piston rod is connected to one of said pair of rails.
20. A device for replacing upper and lower working rolls as set forth in claim 19 wherein rods the upper ends of which engage with bottoms of the bearing boxes of the upper backup roll and the lower ends of which are engaged with the pair of rails are used for positioning the pair of rails in working roll replacement position.
21. A device for replacing upper and lower working rolls as set forth in claim 17 wherein each of said second lifting means comprises a rod the lower end of which rides on one of said pair of rails.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8108413A GB2094684B (en) | 1981-03-18 | 1981-03-18 | Rolling mills |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8108413A GB2094684B (en) | 1981-03-18 | 1981-03-18 | Rolling mills |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2094684A true GB2094684A (en) | 1982-09-22 |
| GB2094684B GB2094684B (en) | 1985-01-30 |
Family
ID=10520459
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8108413A Expired GB2094684B (en) | 1981-03-18 | 1981-03-18 | Rolling mills |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2094684B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0950440A1 (en) * | 1998-04-17 | 1999-10-20 | DANIELI & C. OFFICINE MECCANICHE S.p.A. | Device to remove working rolls in a four-high rolling stand |
| WO2017050535A1 (en) * | 2015-09-24 | 2017-03-30 | Sms Group Gmbh | Roll stand and method for changing work rolls |
-
1981
- 1981-03-18 GB GB8108413A patent/GB2094684B/en not_active Expired
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0950440A1 (en) * | 1998-04-17 | 1999-10-20 | DANIELI & C. OFFICINE MECCANICHE S.p.A. | Device to remove working rolls in a four-high rolling stand |
| US6038905A (en) * | 1998-04-17 | 2000-03-21 | Danieli & C. Officine Meccaniche Spa | Device to remove working rolls in a four-high rolling stand |
| WO2017050535A1 (en) * | 2015-09-24 | 2017-03-30 | Sms Group Gmbh | Roll stand and method for changing work rolls |
| CN108025340A (en) * | 2015-09-24 | 2018-05-11 | Sms集团有限公司 | Rolling-mill housing and the method for replacing working roll |
| RU2686696C1 (en) * | 2015-09-24 | 2019-04-30 | Смс Груп Гмбх | Roll mill and method of replacement work rolls |
| US11565292B2 (en) | 2015-09-24 | 2023-01-31 | Sms Group Gmbh | Roll stand and method for changing work rolls |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2094684B (en) | 1985-01-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |