US3538733A - Prestressed rolling mill with reversed clamping - Google Patents

Prestressed rolling mill with reversed clamping Download PDF

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US3538733A
US3538733A US640972A US3538733DA US3538733A US 3538733 A US3538733 A US 3538733A US 640972 A US640972 A US 640972A US 3538733D A US3538733D A US 3538733DA US 3538733 A US3538733 A US 3538733A
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jacks
rolling mill
jack
rolls
regulating
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US640972A
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Lucien Diolot
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Societe Nouvelle Spidem
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Societe Nouvelle Spidem
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B37/00Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/58Roll-force control; Roll-gap control
    • B21B37/64Mill spring or roll spring compensation systems, e.g. control of prestressed mill stands

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  • the present invention relates to a regulating apparatus of the type specified hereinbefore in the abovementioned copending application with the essential feature that the prestressing jacks on the one hand and the jacks receiving a regulated quantity of fluid on the other hand are controlled by additional jacks having a small cross-section and a long piston stroke, each of these latter jacks being adjusted individually by a geared motor unit, the various units being mounted on shafts arranged in line with a disengageable coupling being provided between adjacent units.
  • FIG. 1 is an elevation partly in section of the general structure of a four-high rolling mill with hydraulic equipment according to my copending US. application Ser. No. 633,299;
  • FIG. 2 is a simplified perspective view of the rolling mill of FIG. 1 in which the improvements proposed by the invention have been diagrammatically included;
  • FIG. 3 is an elevation partly in section of the general structure of the four-high rolling mill of FIG. 1 but being taken along a different section plane than that of FIG. 1.
  • the two uprights 1 of the housing of the prestressed four-high rolling mill support the chocks 2 and 3 of the backing-up rolls and the chocks 4 and 5 of the working rolls.
  • the uprights support fixed blocks 6-6a which are provided with a bore, within which are provided the jacks 7-7a, which jacks are given the task of regulating the spacing of the working rolls.
  • the pistons of these jacks 7-7a are designated as 8-8:; and 9-9a, respectively.
  • the blocks 6-6a can also be used for accommodating other jacks necessary for operation and control of the equipment of a rolling mill; such as, jacks for compensating for the play in parts of the rolling mill, as well as jacks which have the task of applying a prestressing force.
  • Jacks used for compensating for play in the parts may consist of jacks having a horizontal axis and secured in the fixed blocks 6-6a. The function of these jacks would therefore be to compensate for the lateral play of the chocks 4 and 5 of the working rolls in the slide formed by the blocks.
  • a :fluid under pressure can be admitted into each cavity comprised between the two pistons arranged in the same block, through the orifices 10-10a, respectively.
  • a rigid conduit 1.1-11a connects each orifice 10-10a to plunger piston jacks 12.12a, i.e. adjusting jacks having a small cross-section and a long piston stroke.
  • the lower backing-up chock 3 is in contact with the piston 14 of a jack 13.
  • This jack which has a considerable cross-section and is of a single-acting type, is connected on the one hand to an accumulator 16 of known type by a conduit -15 which can be closed by a valve 19, and on the other hand to a hydraulic station or source 18 of known type by a conduit 17 which can be closed by a valve 20.
  • the jack 13 being in communication with the accumulator 16, with valve 19 opened and valve 20 closed,
  • the pistons 8-8a and 9-9a are brought to a suitable position by means of the adjusting jacks 12-12a, and if the total pressing force applied on the piston 14 is greater than the maximum rolling force, the yielding of the housing is constantly compensated by the displacement of the piston 14.
  • FIG. 3 shows the jacks 30 which compensate for play in the rolls.
  • the jacks 30 with their associated conduits 31 are mounted within the uprights support fixed blocks 6-6a which are, in turn, fixed to the two uprights 1.
  • the upper and lower backing-up chocks 2, 3 as well as the chocks 4, 5 of the working rolls can also be seen in FIG. 3.
  • FIG. 2 shows in perspective the two uprights forming the housing of the rolling mill. In each window there are shown the same elements as those described hereinbefore, the same numerals referring to the same parts in both cases.
  • the jacks 77a and also the clamping cylinders 13 are connected respectively 'by the conduits T3, T3, T1 and T2 to a special hydromechanical clamping system.
  • the latter is composed of three plunger-piston jacks V1, V2 and V3, that is to say jacks again having a small cross section and a long piston stroke.
  • the movement of the pistons of these jacks is controlled by means of the reduction gears R1, R2 and R3, these reduction gears themselves being driven by three motors M1, M2 and M3.
  • the shafts of these motors are arranged in line and are connected to one another by the selectively disengageable couplings A1 and A2.
  • the direction of rotation of the geared motor units is such that when the two motors M1 and M2 are coupled by A1 and the third motor by A2, if the plungers of V1 and V2 move into the jacks, the plunger of V3 moves out of that jack.
  • A1 and A2 are disengaged and M3 supplied with fluid pressure, it is possible to vary the pressure in the jacks 7-7a in the two uprights and thus to obtain compensation for yielding.
  • Th s exemplary embodiment according to FIG. 2 which has just been described is also not intended to limit the invention. If the rolling mill comprises other jacks for controlling the clamping of the cylinders, at least one other plunger-piston adjusting jack can be inserted in the hydromechanical circuit and operated.
  • a multi-roll rolling mill having a pair of working rolls disposed between a pair of backing-up rolls in a vertical plane and supported at each end thereof by chocks adjustably supported within respective upright housing members and having prestressing jacks and regulating jacks receiving a regulated quantity of fluid opposed on the chocks supporting the backing-up rolls for regulating the thickness of the rolled product
  • an apparatus for regulating the spacing of the rolls comprising control jack means for regulating said prestressing jacks and said regulating jacks including a plurality of control jacks having a cylinder of small cross-section and a piston therein having a long piston stroke, and
  • a geared motor unit for selectively actuating said control jack means including a plurality of motors each coupled by way of a drive shaft to a respective control jack, said drive shafts being arranged in line with a selectively disengageable coupling between adjacent shafts.
  • each prestressing jack is connected to a separate control jack for selective adjustment of each end of the rolls.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Metal Rolling (AREA)
  • Control Of Metal Rolling (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Description

NOV. 10, 1970 DIQLOT 3,538,733
PRESTRESSED ROLLING MILL WITH REVERSED CLAMPING 7 Filed May 24, 1967 3 Sheets-Sheet l Nov. 10, 1970 p g o-r 3,538,733
PRESTRESSED ROLLING MILL WITH REVERSED CLAMPING Filed May 24, 1967 3 Sheets-Sheet 2 FIG.2
NOV. 10, 1970 DIQLOT 3,538,733
PRESTRESSED ROLLING MILL WITH REVERSED CLAMPING Filed May 24, 1967 3 Sheets-Sheet 3 R 0 M 0 N J up W I k w U \ARRiQ E 5E E United States Patent 3,538,733 PRESTRESSED ROLLING MILL WITH REVERSED CLAMPING Lucien Diolot, Neuilly-sur-Seine, France, asslgnor to Societe Nouvelle Spidem, Paris, France Filed May 24, 1967, Ser. No. 640,972 Claims priority, application France, May 24, 1966,
1m. (:1. B21b 31/32 US. Cl. 72-445 8 Claims ABSTRACT OF THE DISCLOSURE Regulating device for controlling the spacing of cylinders in a rolling mill with prestressing jacks and jacks with a determined quantity of liquid controlled by jacks having a small cross-section and long piston stroke. Each of the last mentioned jacks being capable of being maneuvered individually, the necessary motor reduction gears for driving said jacks being mounted in line with disengaging clutches connected therebetween.
An apparatus for simply and efficiently regulating the spacing of the rolls in a prestressed rolling mill has already been proposed in my copending application Ser. No. 633,- 299, filed Apr. 24, 1967, and entitled Apparatus for Varying the Forces Exerted on the Work Rolls in Multi- Roll Rolling Mills. In addition to the use of prestressing jacks, this apparatus can comprise jacks with a regulated quantity of fluid acting on the backing-up chocks for regulating the thickness which the rolled product is to be iven. g The present invention proposes the addition of improvements to an apparatus of this type in order to multiply for the rolling mill user the possibilities of correcting the position or regulating the spacing of the rolls during the course of a rolling operation.
The present invention relates to a regulating apparatus of the type specified hereinbefore in the abovementioned copending application with the essential feature that the prestressing jacks on the one hand and the jacks receiving a regulated quantity of fluid on the other hand are controlled by additional jacks having a small cross-section and a long piston stroke, each of these latter jacks being adjusted individually by a geared motor unit, the various units being mounted on shafts arranged in line with a disengageable coupling being provided between adjacent units.
It is an object of the present invention to provide improvements in regulating apparatus for rolling mills.
It is another object of the present invention to provide a regulating apparatus for rolling mills capable of effecting selected adjustments in the position and spacing of the rolls.
It is a further object of the present invention to provide a regulating apparatus for rolling mills capable of effecting greatly simplified control over the rolling force of the mill.
These and other objects, features and advantages of the present invention will become more apparent from the following detailed description thereof, when taken with the accompanying drawings, which illustrate one exemplary embodiment of the invention, and wherein:
FIG. 1 is an elevation partly in section of the general structure of a four-high rolling mill with hydraulic equipment according to my copending US. application Ser. No. 633,299;
FIG. 2 is a simplified perspective view of the rolling mill of FIG. 1 in which the improvements proposed by the invention have been diagrammatically included; and
FIG. 3 is an elevation partly in section of the general structure of the four-high rolling mill of FIG. 1 but being taken along a different section plane than that of FIG. 1.
As FIG. 1 shows, the two uprights 1 of the housing of the prestressed four-high rolling mill support the chocks 2 and 3 of the backing-up rolls and the chocks 4 and 5 of the working rolls.
At each side of the window formed by the uprights 1 the uprights support fixed blocks 6-6a which are provided with a bore, within which are provided the jacks 7-7a, which jacks are given the task of regulating the spacing of the working rolls. The pistons of these jacks 7-7a are designated as 8-8:; and 9-9a, respectively.
Although it is not illustrated, it should be noted that the blocks 6-6a can also be used for accommodating other jacks necessary for operation and control of the equipment of a rolling mill; such as, jacks for compensating for the play in parts of the rolling mill, as well as jacks which have the task of applying a prestressing force. Jacks used for compensating for play in the parts may consist of jacks having a horizontal axis and secured in the fixed blocks 6-6a. The function of these jacks would therefore be to compensate for the lateral play of the chocks 4 and 5 of the working rolls in the slide formed by the blocks.
A :fluid under pressure can be admitted into each cavity comprised between the two pistons arranged in the same block, through the orifices 10-10a, respectively. A rigid conduit 1.1-11a connects each orifice 10-10a to plunger piston jacks 12.12a, i.e. adjusting jacks having a small cross-section and a long piston stroke.
The lower backing-up chock 3 is in contact with the piston 14 of a jack 13. This jack, which has a considerable cross-section and is of a single-acting type, is connected on the one hand to an accumulator 16 of known type by a conduit -15 which can be closed by a valve 19, and on the other hand to a hydraulic station or source 18 of known type by a conduit 17 which can be closed by a valve 20.
The jack 13 being in communication with the accumulator 16, with valve 19 opened and valve 20 closed,
to regulate the thickness to be rolled the pistons 8-8a and 9-9a are brought to a suitable position by means of the adjusting jacks 12-12a, and if the total pressing force applied on the piston 14 is greater than the maximum rolling force, the yielding of the housing is constantly compensated by the displacement of the piston 14.
If the jack 13 is subjected to suitable pressure and then the valves 19 and 20 are closed, it is possible to roll while influencing the value of the forces exerted by the secondary jack by means of the hydromechanical clamping systern.
The volume of oil stored in the jack 13 and the conduit system from this jack to the valves 19 and 20 being constant, its pressure varies if the rolling force changes, and this variation takes place in the sense of an additional compensation for the yielding of the housing.
By locking the pressure acting on the pistons 8-811 and 99a to a fixed value, the valve 19 being closed and the valve 20 opened, it is possible to roll in conventional manner.
FIG. 3 shows the jacks 30 which compensate for play in the rolls. The jacks 30 with their associated conduits 31 are mounted within the uprights support fixed blocks 6-6a which are, in turn, fixed to the two uprights 1. The upper and lower backing-up chocks 2, 3 as well as the chocks 4, 5 of the working rolls can also be seen in FIG. 3.
FIG. 2 shows in perspective the two uprights forming the housing of the rolling mill. In each window there are shown the same elements as those described hereinbefore, the same numerals referring to the same parts in both cases.
The jacks 77a and also the clamping cylinders 13 are connected respectively 'by the conduits T3, T3, T1 and T2 to a special hydromechanical clamping system. The latter is composed of three plunger-piston jacks V1, V2 and V3, that is to say jacks again having a small cross section and a long piston stroke. The movement of the pistons of these jacks is controlled by means of the reduction gears R1, R2 and R3, these reduction gears themselves being driven by three motors M1, M2 and M3. The shafts of these motors are arranged in line and are connected to one another by the selectively disengageable couplings A1 and A2.
The direction of rotation of the geared motor units is such that when the two motors M1 and M2 are coupled by A1 and the third motor by A2, if the plungers of V1 and V2 move into the jacks, the plunger of V3 moves out of that jack.
This arrangement has the following advantages for the rolling mill:
With M1, M2, M3, all supplied with fluid pressure and A1, A2 engaged, it is possible to clamp or unclamp the rolls.
By supplying M1 or M2 with fluid pressure and disengaging A1 and A2, it is possible to clamp on the right or on the left of the rolls according to need.
If A1 and A2 are disengaged and M3 supplied with fluid pressure, it is possible to vary the pressure in the jacks 7-7a in the two uprights and thus to obtain compensation for yielding.
Of course the rolling mill retains the operating advantages proposed by the basic combination disclosed in any aforementioned copending application.
Th s exemplary embodiment according to FIG. 2 which has just been described is also not intended to limit the invention. If the rolling mill comprises other jacks for controlling the clamping of the cylinders, at least one other plunger-piston adjusting jack can be inserted in the hydromechanical circuit and operated.
I have shown and described one embodiment in accordance with the present invention. It is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to a person skilled in the art and I, therefore, do not wish to be limited to the details shown and described herein, but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.
I claim:
1. In a multi-roll rolling mill having a pair of working rolls disposed between a pair of backing-up rolls in a vertical plane and supported at each end thereof by chocks adjustably supported within respective upright housing members and having prestressing jacks and regulating jacks receiving a regulated quantity of fluid opposed on the chocks supporting the backing-up rolls for regulating the thickness of the rolled product, an apparatus for regulating the spacing of the rolls comprising control jack means for regulating said prestressing jacks and said regulating jacks including a plurality of control jacks having a cylinder of small cross-section and a piston therein having a long piston stroke, and
a geared motor unit for selectively actuating said control jack means including a plurality of motors each coupled by way of a drive shaft to a respective control jack, said drive shafts being arranged in line with a selectively disengageable coupling between adjacent shafts.
2. The combination defined in claim 1 wherein all of said regulating jacks are connected to a single control jack for simultaneous actuation thereof.
3. The combination defined in claim 1 wherein each prestressing jack is connected to a separate control jack for selective adjustment of each end of the rolls.
4. The combination defined in claim 3 wherein said prestressing jacks are mounted with the pistons thereof supporting the chocks of the lower backing-up roll.
5. The combination defined in claim 1 further char- 25 acterized in that. supporting blocks are arranged at the inside of the window of each of the upright housing members against the inner wall thereof, said blocks having bores at the inside thereof, and prestressing jacks accommodated within the bores of said blocks.
6. The combination defined in claim wherein the supporting blocks are likewise arranged so as to comprise jacks for compensating the lateral play of the chocks in the slide.
7. The combination defined in claim 2 wherein said control jack connected to said regulating jacks is actuated by said geared motor unit in the opposite sense to the actuation of said control jacks actuating said prestressing jacks.
8. The combination defined in claim 1 wherein only a single prestressing jack is provided on each side of said rolls, said single prestressing jack being mounted so as to support a chock of the lower backing-up roll, the chocks of the upper backing-up roll being restricted at the upper end by said housing members.
References Cited UNITED STATES PATENTS 2,056,409 10/1936 Ross 72-245 3,286,495 11/1966 Diolot 72245 CHARLES W. LANHAM, Primary Examiner 3 B. J. MUSTAIKIS, Assistant Examiner
US640972A 1963-02-11 1967-05-24 Prestressed rolling mill with reversed clamping Expired - Lifetime US3538733A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR924375A FR1356340A (en) 1963-02-11 1963-02-11 Hydraulic cedage compensation device for hydromechanical clamping rolling mill
BE643011A BE643011A (en) 1963-02-11 1964-01-27
FR62716A FR90470E (en) 1963-02-11 1966-05-24 Reverse clamping prestressed rolling mill

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US343380A Expired - Lifetime US3286495A (en) 1963-02-11 1964-02-07 Deformation compensating hydraulic device for rolling mills of the hydraulic mechanical pressure type
US640972A Expired - Lifetime US3538733A (en) 1963-02-11 1967-05-24 Prestressed rolling mill with reversed clamping

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US343380A Expired - Lifetime US3286495A (en) 1963-02-11 1964-02-07 Deformation compensating hydraulic device for rolling mills of the hydraulic mechanical pressure type

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BE (1) BE643011A (en)
DE (1) DE1452005A1 (en)
ES (1) ES339799A2 (en)
FR (2) FR1356340A (en)
GB (2) GB1049796A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3864955A (en) * 1973-12-04 1975-02-11 Blaw Knox Foundry Mill Machine Rolling mill stand

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FR1356340A (en) * 1963-02-11 1964-03-27 Spidem Ste Nle Hydraulic cedage compensation device for hydromechanical clamping rolling mill
FR1481166A (en) * 1966-04-04 1967-05-19 Spidem Ste Nle Engraving machine by cylinders under hydraulic clamping and with preload
GB1190738A (en) * 1966-08-16 1970-05-06 United Eng Foundry Co Means for indicating the Roll Pass Opening in a Rolling Mill or Calender
FR1511608A (en) * 1966-12-19 1968-02-02 Loire Atel Forges Device for regulating the thickness of rolled products and rolling mill provided with such a device
FR1511609A (en) * 1966-12-19 1968-02-02 Loire Atel Forges Thickness regulator device for rolled products and rolling mill including the application
US3524495A (en) * 1967-03-01 1970-08-18 Vitaly Maximovich Niskovskikh Roller zone in the system of secondary cooling in continuous casting plants
GB1218572A (en) * 1967-05-10 1971-01-06 British Aircraft Corp Ltd Rolling mills
US3635060A (en) * 1968-09-03 1972-01-18 Mitsubishi Heavy Ind Ltd Thrusting arrangement for a rolling mill
DE2108783C3 (en) * 1971-02-24 1975-12-04 Nowosibirskij Metallurgitscheskij Sawod Imeni A.N. Kusmina, Nowosibirsk (Sowjetunion) Device for the automatic control of the thickness of flat rolled material
US4471639A (en) * 1982-11-01 1984-09-18 E. W. Bliss Company, Inc. Roll orientation control system for straightening machines
US4507996A (en) * 1982-11-15 1985-04-02 Preston Engravers, Inc. Device for transferring and monitoring load to die roll
CN110026440B (en) * 2019-03-20 2023-10-20 宁波中超机器有限公司 Hydraulic pressing device for rolling mill and calibration method thereof

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US2056409A (en) * 1933-07-10 1936-10-06 William G Ross Rolling mill
US3286495A (en) * 1963-02-11 1966-11-22 Spidem Ste Nle Deformation compensating hydraulic device for rolling mills of the hydraulic mechanical pressure type

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US2119390A (en) * 1936-08-26 1938-05-31 Mesta Machine Co Rolling mill
BE470806A (en) * 1946-01-29
FR1215740A (en) * 1958-10-31 1960-04-20 Siderurgie Fse Inst Rech Improvements to rolling mill adjustment devices with cedage compensation
US2998238A (en) * 1959-09-11 1961-08-29 Lake Erie Machinery Corp Controller for the back pressure against the main ram of a press

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2056409A (en) * 1933-07-10 1936-10-06 William G Ross Rolling mill
US3286495A (en) * 1963-02-11 1966-11-22 Spidem Ste Nle Deformation compensating hydraulic device for rolling mills of the hydraulic mechanical pressure type

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3864955A (en) * 1973-12-04 1975-02-11 Blaw Knox Foundry Mill Machine Rolling mill stand

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FR90470E (en) 1967-12-22
US3286495A (en) 1966-11-22
ES339799A2 (en) 1968-05-16
FR1356340A (en) 1964-03-27
DE1452005A1 (en) 1969-10-02
BE643011A (en) 1964-07-27
GB1161715A (en) 1969-08-20
GB1049796A (en) 1966-11-30

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