US3754426A - Roll changing arrangement for a rolling mill - Google Patents
Roll changing arrangement for a rolling mill Download PDFInfo
- Publication number
- US3754426A US3754426A US00216599A US3754426DA US3754426A US 3754426 A US3754426 A US 3754426A US 00216599 A US00216599 A US 00216599A US 3754426D A US3754426D A US 3754426DA US 3754426 A US3754426 A US 3754426A
- Authority
- US
- United States
- Prior art keywords
- chocks
- supporting
- roll
- tracks
- pair
- 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.)
- Expired - Lifetime
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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
Definitions
- ABSTRACT The disclosure of this invention relates to a rolling mill wherein the checks of the work roll on the drive side of the mill are split to enable the work rolls to be removed and replaced while strip is still being passed between the rolls.
- the checks of the work rolls on the operating side can be nested or split.
- the work roll chocks are provided with wheels which during the roll changing operation are carried by a pair of upper tracks secured to the housings and checks of the upper backup roll and by a pair of lower tracks carried only by the housings.
- a bridge is located at the front of the mill between a side shifting unit and the mill. The bridge has tracks which serve as continuations of the housing tracks and which receive the wheels of the work roll chocks as the rolls are brought to and from the mill to transfer them from and to the side shifter.
- the present invention provides an improved mill arrangement for economically and efficiently carrying out the aforesaid object.
- It provides a work roll chock and supporting arrangement that allows the work rolls to be held and transferred into and out of the mill without interfering with the passing strip.
- the present invention provides for the drive side chocks of the work rolls to be split and for the upper chock to be carried by a first track and the lower chock by a second track, whereas the operating side chocks of the work roll are nested in which the lower chock thereof is received in the upper chock, and the operating side lower chock is carried by the second track, whereas the operating side upper chock is carried by both the first and second tracks.
- FIG. I is an elevational view of one of the stands of a tandem mill incorporating the features of the present invention
- FIG. 2 is an elevational view at the operators side of the window of the mill shown in FIG. 1,
- FIG. 3 is a sectional view taken on line 3-3 of FIG.
- FIG. 5 is a sectional view taken on line 5-5 of FIG.
- FIG. 1 there is illustrated a rolling upper backup roll 16 and the bottom of the screws 26 have been removed to the right, as shown in FIG. I.
- the sled 25 at the The chocks of the lower backup roll 17 are carried in a roll changing sled 25, the lower surface of which is received in the windows 12 and 13.
- the chocks 24 of the upper backup roll 16 are adapted to be engaged indirectly by screws 26 arranged in each housing 10 and 11.
- FIG. 1 actually showing the chocks 24 of the upper backup roll 16 separated from the screws 26 since this drawing is meant to depict the roll changing position of the work rolls.
- the pressureblock assemblies 27 that are provided between the chocks 24 of the upper backup roll 16 and the bottom of the screws 26 have been removed to the right, as shown in FIG. I.
- the sled 25 at the bottom of the mill rests on pistons of piston cylinder assemblies 28 arranged in the lower portion of each housing 10 and 11.
- the work rolls l4 and 15 are adapted to be driven and for which purpose there are provided driving spindles 31 connected to a power source, not shown.
- FIG. 2 depicts the characteristics of the front or operating side chocks of the work rolls l4, l5, l6 and 17.
- FIG. 2 depicts the characteristics of the front or operating side chocks of the work rolls l4 and I5, and associated mill elements.
- the chock 18 of the upper work roll 14 has downwardly extending leg portions 36 that provide an opening 37 for receiving the vertical sides of the lower front work roll chock 22.
- the adjacent vertical surfaces of these chocks are provided in the usual manner with liners 38.
- Similar liners are provided between the housing 10 and the outside vertical surfaces of the chock of the upper work roll 14, in which connection it will be noted that the housing is indented by portions 42.
- Wheels 40 are provided at the lower portions of the chock 22, and, while not seen in FIG. 2, they do appear in FIGS. 1, 4 and 5.
- the work mill comprising two upright spaced-apart housings l0 and 11, each of which, according to customary designs, are provided with windows 12 and 13 into which are received the bearing chock assemblies of the rolls of the mill.
- the rolls comprise work rolls 14 and 15, each of which are backed up by backup rolls l6 and 17, respectively, and arranged on the opposite side of the pass-line of the mill.
- the work roll 14 has bearing chock assemblies 18 and 19, whereas the lower work roll 15 has bearing chock assemblies 22 and 23.
- the backup rolls have bearing chock assemblies 24.
- Somewhat larger wheels 46 are provided in the legs 36 of thechock 18 which engage tracks 47 mounted in the housings l0 and 11. These tracks, as illustrated in FIGS. 1, 4 and 5, run from the front of the-mill through the space between the housings and terminate at the back of the housing 11, actually having an extended portion 48 beyond the housing 11, the purpose of which will be described later.
- the vertical surface of the operating side chocks 24 of the backup rolls I6 and 17 are provided with the usual liners 49 that allow them to slide vertically relative to the housing 10.
- FIG. 3 depicts that back or drive side of the rolling mill
- the chocks I9 and 23 of the work rolls I4 and 15 are split in counter-distinction to the nested relationship of the work roll chocks l8 and 22 at the operating side of the mill.
- This split construction allows the chocks 19 and 23 to be axially moved in and out of the mill without interfering with a strip passing between the rolls 14 and 15.
- the chock 19 of the upper roll 14 has lined vertical surfaces that engage projecting portions 51 of the housing 11, which portions are protected by liners 52.
- horizontal extending wheels 53 are provided which engage tracks 54 extending downwardly from the chock 24 of the backup roll 16.
- the tracks 54 as shown in FIG.
- the chock 23 of the lower work roll is also provided with liners 57 that engage the portions 51 of the housing 11 and have two pairs of spaced-apart wheels 58 arranged at their outer lower portions that engage the upper surfaces of the tracks 47, already identified with respect to FIG. 2.
- liners 57 that engage the portions 51 of the housing 11 and have two pairs of spaced-apart wheels 58 arranged at their outer lower portions that engage the upper surfaces of the tracks 47, already identified with respect to FIG. 2.
- the chock 23 is provided with balance cylinder assemblies 59, shown retracted in view of the roll changing position of the mill components.
- the drive side backup chocks 24 for the backup rolls l6 and 17 are provided with vertical liners 60 that allow for vertical movement of the backup chocks.
- FIGS. 1, 4 and 5 the two pairs of wheels 40 and 46 of the frontwork roll chocks l8 and 22 generally fall in the same longitudinal plane.
- the foremost wheels 40 mounted on the work roll chock 22 of the lower roll 15 fall immediately ahead of the wheels 46, which are secured to the leg portions 36 of the chock 18 of the upper work roll 14. Since the upper work roll 14 must move towards the lower roll 15 to set the pass opening of the mill during rolling, the tracks 47 are provided with slots 63 immediately below the operating position of the wheels 46 of the upper work roll chock 18.
- the pair of wheels 45 at the top of the chock 18 are spaced to the left of the wheels 46, as one views FIG. 4, and during roll changing are in engagement with the tracks 44.
- the chock 18 is only supported by the wheels 45, whereas, during the remainder of the time, the chock will be supported by both the wheels 45 and the wheels 46.
- the two pairs of wheels 58 are spaced apart with reference to the length of the slots 63 in the rails 47 so that, in removing the rolls from the mill, the chock 23 will be supported by the back wheel 58 while the front wheel 58 is passing over the slot 63. The reverse will take place when the rolls are moved into the mill.
- the chock 19 at the drive side of the work roll 14 its pair of wheels 53, as noted in FIG. 4, are arranged at the very back of the chock assembly so that the chock 19 can be supported by the track network 44, 54 and 56 during the entire period that the work rolls are moved from the mill.
- the front chock 24 of the backup roll 16 is provided with an extending portion 65 on which the tracks 44 are formed and which cooperation with the bridge 33 is shown at the left-hand side of FIG. 4.
- FIG. 1 In referring now to FIG. 1 and with reference to the bridge unit 33, it will be noted that it is provided with a pair of lower tracks 67 which form continuations of the tracks 47 that service the lower work roll chocks 22 and 23.
- a pair of upper tracks 68 are provided at the top of the bridge unit 33 that serve as continuations of the tracks 44 that service the chocks 18 and 19 of the upper work roll 14.
- the bridge is designed to be readily inserted and removed from in front of the mill and is actually mounted on a base member 69 or extension that serves as an extension of a car assembly 71, the car being mounted on rails 72 which are engaged by wheels 73 rotatably carried by the chassis of the car 71, the car 71 being driven by a power source 74.
- the extension 69 when positioned in front of the mill, engages a bracket 75 that supports the front end of the bridge 33.
- the car 71 also supports the side shifter 34 which is provided with two pairs of side-by-side tracks 76 for supporting a new pair of work roll assemblies to be inserted into the mill and a pair of used work roll assemblies that are retracted from the mill.
- the tracks of each of these pairs depending on which pair is positioned in front of the mill, will serve as extensions of the tracks 67 and 68 of the bridge 33.
- the positioning of the tracks is brought about by a rack and pinion 77 that drives the side shifter 34 over the tracks 78 in a direction parallel to the steel line of the mill.
- a second bridge unit 79 is provided having a pair of spaced-apart tracks 80 that form continuations of the tracks 68 of the bridge unit 33. It is important to note that the tracks 80 are made long enough so that when the roll assemblies are positioned on the side shifter, the wheels 53 of the upper drive side chock 19 of the work roll 14 will still be in engagement with and supported by the tracks 80. It will also be noted that a second bridge unit 79 will be provided for the new roll set which, when shifted into position in front of the mill, will line up with the bridge unit 33.
- the lower drive side work roll chock 23 is provided with a hook 81 that is adapted to be engaged by a cooperative hook element 82 connected to a ram 83.
- the ram is adapted to be driven through the mill by a power means, not shown.
- the front end of the ram 83 is supported by two pairs of wheels 84 arranged to engage the extension 48 of the tracks 47.
- the lowering and raising of the backup rolls l7 and 16, respectively, provides an opening between the work roll and brings them out of engagement with the strip passing through the mill.
- the raising of the chocks 24 of the backup roll 16 is accomplished by lifting the screws 26 a sufficient distance to allow the bearing blocks 27 to be withdrawn from under the screws to a position shown in FIG. 1.
- the actual amount or distance that the upper backup roll 16 is raised is controlled by the consideration that the tracks 44 must be brought into alignment with the tracks 68 of the bridge unit 33, the tracks 68 being a fixed distance from the floor line.
- the registry of the tracks can be accomplished in any number of ways, for example, by a pin operated by a piston cylinder assembly that will position the upper chocks 24 relative to the housings l0 and 11.
- the balance cylinders for example, the work roll balance cylinders 43 and 59, are retracted so as to avoid their interfering with or contacting the strip as the rolls are moved axially.
- the car 71 Prior to the separation of the work rolls preparatory to roll changing, the car 71, which, as noted before, includes the bridge unit 33 and the bridge unit 79, is brought to a position in front of the mill and arranged so that an empty pair of tracks 76 are provided in front of the mill toreceive the roll assemblies 14 and to be removed from the mill.
- the rolls are removed by simply operating the ram 83 to cause the pair of rolls l4 and 15 with their chock assemblies to move over their associated tracks onto the bridge unit 33 and eventually onto the side shifter 34.
- the relationship of the several wheels to the tracks and slots 63 provide that the rolls throughout the entire transport will be supported in a manner that they are held out of contact with the strip passing between them.
- chocks l9 and 23 at the drive side of the work rolls 14 areindividually supported in a spaced-apart relationship and their split construction allows them to be moved over and under the strip passing through the mill.
- the procedure is essentially reversed as above described, in which the side shifter 34 will position the second bridge unit 79 and the new set of rolls in front of the mill to be engaged by the ram 83.
- bearing chocks at the respective ends of said working rolls being arranged to form cooperative pairs of bearing chocks
- said cooperative pairs of bearing chocks at the drive side being split in a manner that the adjacent surfaces thereof can be spaced from said mill passline during roll changing
- said cooperative pair of bearing chocks at the operating side being nested in a manner that one of the bearing chocks thereof is received and carried by the other bearing chock, and
- a rolling mill comprising:
- a backup roll for at least said uppermost working roll having bearing chocks on its front and back ends received in said housings,
- said chocks of said uppermost working roll each having a supporting means
- said chocks of said lowermost working roll each having a supporting means
- first track means arranged adjacent to the chocks of said uppermost working roll for supporting these chocks during roll changing
- second track means arranged adjacent to the chocks of said lowermost working roll for supporting these chocks during roll changing.
- said first track means includes a pair of spaced-apart first supporting tracks extending between said housings adjacent to the top of said chocks of said uppermost working roll, and
- said second track means includes a fourth pair of supporting tracks carried by and extending between and through said housings adjacent the bottom of said chocks of said lowermost working rolls,
- said fourth pair of supporting tracks having openings for receiving said additional supporting means
- said back side chocks of the lowermost working roll having a pair of supporting means spaced apart sufficiently to span said openings.
- said openings comprise slots formed in each of said fourth wherein said supporting means of said front chock of said uppermost working roll and said additional supporting means thereof are so arranged that said supporting means support the front chock of said uppermost working roll when said additional supporting means is over said slots.
- a working roll receiving means arranged adjacent to the side of said bridge member opposite said hous ing for receiving a pair of the rolls withdrawn from said housings
- said receiving means including two pairs of supporting tracks for receiving two pairs of working rolls arranged side by side, and
- said engaging means including support members for engaging said second track means.
- said receiving means includes a second bridge having a pair of tracks for supporting the back chock of said uppermost working roll when received by said receiving means.
- said car having means for receiving a side shifter
- said car having means for carrying said bridge.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Metal Rolling (AREA)
Abstract
Description
Claims (11)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB543671A GB1370793A (en) | 1971-02-25 | 1971-02-25 | Roll changing arrangement for a rolling mill |
Publications (1)
Publication Number | Publication Date |
---|---|
US3754426A true US3754426A (en) | 1973-08-28 |
Family
ID=9796176
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00216599A Expired - Lifetime US3754426A (en) | 1971-02-25 | 1972-01-10 | Roll changing arrangement for a rolling mill |
Country Status (6)
Country | Link |
---|---|
US (1) | US3754426A (en) |
JP (1) | JPS512306B1 (en) |
CA (1) | CA944188A (en) |
DE (1) | DE2204971A1 (en) |
FR (1) | FR2131972B1 (en) |
GB (1) | GB1370793A (en) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3864954A (en) * | 1973-12-04 | 1975-02-11 | Blaw Knox Foundry Mill Machine | Roll changers |
US3913368A (en) * | 1974-09-04 | 1975-10-21 | Blaw Knox Foundry Mill Machine | Tandem rolling mill |
US6038905A (en) * | 1998-04-17 | 2000-03-21 | Danieli & C. Officine Meccaniche Spa | Device to remove working rolls in a four-high rolling stand |
US20020178936A1 (en) * | 2001-05-30 | 2002-12-05 | New Gencoat, Inc. | Wringer roller system |
US20040144150A1 (en) * | 2001-05-18 | 2004-07-29 | Germain Le Viavant | Device for disassembling rolling mill cylinders |
DE19815029B4 (en) * | 1998-04-03 | 2006-07-27 | Sms Demag Ag | Roll change process for a rolling stand |
US11565292B2 (en) | 2015-09-24 | 2023-01-31 | Sms Group Gmbh | Roll stand and method for changing work rolls |
EP4163027A1 (en) * | 2021-10-05 | 2023-04-12 | Primetals Technologies Limited | Rolling mill stand and method of changing a work roll assembly thereof |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2418041A1 (en) * | 1978-02-22 | 1979-09-21 | Clesid Sa | Roller-change system for strip rolling machine - lowers cased roller assembly onto rails for transverse movement onto transporter |
JPS5839001B2 (en) * | 1979-06-28 | 1983-08-26 | 石川島播磨重工業株式会社 | Strip winding device for rolling mill rolls |
JPS57138991A (en) * | 1981-02-23 | 1982-08-27 | Toyo Seimitsu Kogyo Kk | Screen printing plate |
CN105382030B (en) * | 2015-12-14 | 2018-02-23 | 安徽楚江特钢有限公司 | A kind of work roll changing method of milling train |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3312096A (en) * | 1963-10-03 | 1967-04-04 | Davy & United Eng Co Ltd | Rolling mills |
US3323345A (en) * | 1951-01-28 | 1967-06-06 | Blaw Knox Co | Roll changing apparatus |
US3446050A (en) * | 1965-12-06 | 1969-05-27 | United Eng Foundry Co | Rolling mills |
US3593554A (en) * | 1968-08-09 | 1971-07-20 | Davy & United Eng Co Ltd | Rolling mills |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL268267A (en) * | 1960-08-18 | |||
US3436945A (en) * | 1967-02-21 | 1969-04-08 | Textron Inc | Roll-changing apparatus for a rolling mill |
FR1538634A (en) * | 1967-07-28 | 1968-09-06 | Loire Atel Forges | Device for dismantling rolling rolls, or a set of rolls from a leveling machine |
-
1971
- 1971-02-25 GB GB543671A patent/GB1370793A/en not_active Expired
-
1972
- 1972-01-10 US US00216599A patent/US3754426A/en not_active Expired - Lifetime
- 1972-02-03 DE DE19722204971 patent/DE2204971A1/en active Pending
- 1972-02-11 CA CA134,563A patent/CA944188A/en not_active Expired
- 1972-02-24 FR FR7206251A patent/FR2131972B1/fr not_active Expired
- 1972-02-25 JP JP47019015A patent/JPS512306B1/ja active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3323345A (en) * | 1951-01-28 | 1967-06-06 | Blaw Knox Co | Roll changing apparatus |
US3312096A (en) * | 1963-10-03 | 1967-04-04 | Davy & United Eng Co Ltd | Rolling mills |
US3446050A (en) * | 1965-12-06 | 1969-05-27 | United Eng Foundry Co | Rolling mills |
US3593554A (en) * | 1968-08-09 | 1971-07-20 | Davy & United Eng Co Ltd | Rolling mills |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3864954A (en) * | 1973-12-04 | 1975-02-11 | Blaw Knox Foundry Mill Machine | Roll changers |
US3913368A (en) * | 1974-09-04 | 1975-10-21 | Blaw Knox Foundry Mill Machine | Tandem rolling mill |
DE19815029B4 (en) * | 1998-04-03 | 2006-07-27 | Sms Demag Ag | Roll change process for a 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 |
US20040144150A1 (en) * | 2001-05-18 | 2004-07-29 | Germain Le Viavant | Device for disassembling rolling mill cylinders |
US20020178936A1 (en) * | 2001-05-30 | 2002-12-05 | New Gencoat, Inc. | Wringer roller system |
US6786144B2 (en) * | 2001-05-30 | 2004-09-07 | New Gencoat, Inc. | Wringer roller system |
US11565292B2 (en) | 2015-09-24 | 2023-01-31 | Sms Group Gmbh | Roll stand and method for changing work rolls |
EP4163027A1 (en) * | 2021-10-05 | 2023-04-12 | Primetals Technologies Limited | Rolling mill stand and method of changing a work roll assembly thereof |
WO2023057182A1 (en) * | 2021-10-05 | 2023-04-13 | Primetals Technologies, Limited | Rolling mill stand and method of changing a work roll assembly thereof |
Also Published As
Publication number | Publication date |
---|---|
GB1370793A (en) | 1974-10-16 |
FR2131972A1 (en) | 1972-11-17 |
DE2204971A1 (en) | 1972-08-31 |
CA944188A (en) | 1974-03-26 |
JPS512306B1 (en) | 1976-01-24 |
FR2131972B1 (en) | 1974-10-18 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: PITTSBURGH NATIONAL BANK Free format text: SECURITY INTEREST;ASSIGNOR:WEAN UNITED, INC., A CORP.OF OH;REEL/FRAME:004458/0765 Effective date: 19850610 |
|
AS | Assignment |
Owner name: PITTSBURGH NATIONAL BANK,PENNSYLVANIA Free format text: SECURITY INTEREST;ASSIGNOR:WEAN UNITED, INC., A CORP. OH.;REEL/FRAME:004792/0307 Effective date: 19860630 Owner name: PITTSBURGH NATIONAL BANK Free format text: SECURITY INTEREST;ASSIGNOR:WEAN UNITED, INC., A CORP. OH.;REEL/FRAME:004792/0307 Effective date: 19860630 |
|
AS | Assignment |
Owner name: WEAN UNITED, INC. Free format text: RELEASED BY SECURED PARTY;ASSIGNOR:PITTSBURGH NATIONAL BANK;REEL/FRAME:004925/0218 Effective date: 19880509 |
|
AS | Assignment |
Owner name: UNITED ENGINEERING ROLLING MILLS, INC. Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:WEAN INCORPORATED;REEL/FRAME:004920/0256 Effective date: 19880610 |
|
AS | Assignment |
Owner name: UNITED ENGINEERING, INC. Free format text: CHANGE OF NAME;ASSIGNOR:UNITED ENGINEERING ROLLING MILLS, INC.;REEL/FRAME:005285/0209 Effective date: 19900425 |