US3672438A

US3672438A - Guide-roll rack and supporting structure therefor

Info

Publication number: US3672438A
Application number: US74806A
Authority: US
Inventors: Gottfried Hofmann; James T Stull
Original assignee: United States Steel Corp
Current assignee: United States Steel Corp
Priority date: 1970-09-23
Filing date: 1970-09-23
Publication date: 1972-06-27
Anticipated expiration: 1989-06-27
Also published as: AU3364371A; IT939858B; ZA716254B; DE2146963A1; BE772831A; NL7113037A; FR2123251B3; FR2123251A3

Abstract

A guide roll rack and supporting structure for use in a continuous casting machine. The rack is formed in vertically aligned sections. The supporting structure includes pairs of vertically spaced arms hinged to the support columns. The rack sections are removably carried on the arms, whereby the rack sections can swing with the arms from an operative position in the machine to a position outside the machine for easy removal and replacement.

Description

United States Patent Hofmann et al.

[4 1 June 27, 1972 [54] GUIDE-ROLL RACK AND SUPPORTING STRUCTURE THEREFOR [72] lnventors: Gottfried l-lofmann, Brentwood Borough, Allegheny County; James T. Stull, Jackson Township, Butler County, both of Pa.

[73] Assignee: United States Steel Corporation [22] Filed: Sept. 23, 1970 [21] Appl. No.: 74,806

52 us. c1 ..164/282 [58] Field of Search 164/82, 282, 283; 193 2 A, 193 2 D, 14, 15, 25,35, 37

[56] References Cited UNITED STATES PATENTS 3,528,488 9 1970 Bode ..164/282 2,284,503 5/1942 Williams... .....164/282 2,770,021 11/1956 Harter et al ..164/282 x FOREIGN PATENTS OR APPLICATIONS 719,632 10/1965 Canada ..164/283 961,182 6/1964 England... ..l64/282 993,026 5/1965 England... ..164/282 997,215 7/1965 Englandm. ..164/282 859,610 1/1961 England ..l64/283 Primary Examiner-Evon C. Blunk Assistant Examiner-W. Scott Carson Altomey-Walter P. Wood ABSTRACT A guide roll rack and supporting structure for use in a continuous casting machine, The rack is formed in vertically aligned sections. The supporting structure includes pairs of vertically spaced arms hinged to the support columns. The rack sections are removably carried on the arms, whereby the rack sections can swing with the arms from an operative position in the machine to a position outside the machine for easy removal and replacement.

9 Claims, 6 Drawing Figures PATENTEBJUN 2 7 m2 SHEET 10F 5 ATTOIQ/VEV.

PATENTEnJum 1972 672,438

sum 3 or 5 wwwmes. G077'FR/ED HOFMAN/V JAMES r. STULL Mam/m4 PATENTEDJUHN I972 3. 672.438

SHEET

5 or 5 lA/VEVTORS. GOTTFR/ED HOFMA/VA/ JAMES 7T .STULL 8y MW ATTORNEY.

GUIDE-ROLL RACK AND SUPPORTING STRUCTURE THEREFOR This invention relates to an improved guide roll rack and supporting structure therefor for use in a continuous-casting machine.

In a conventional continuous-casting operation, liquid metal is poured through an open-ended water-cooled vertically oscillating mold. A casting, which at this stage has only a relatively thin solidified skin and a liquid core, emerges continuously from the lower end of the mold. Immediately beneath the mold the casting travels through a series of idler guide rolls, where water is sprayed on its surface to effect further solidification. The guide rolls define a pass which must be accurately aligned throughout its height and accurately aligned with the mold to confine the casting. Any misalignment of the guide rolls can rupture the skin of the casting and cause a break-out of liquid metal. The severe conditions under which guide rolls operate necessitate that they be removed frequently for maintenance or replacement. It is of course necessary to shut down the whole operation to change guide rolls.

Although our invention is not thus limited, our guide roll rack is particularly suited for use in multiple strand casting I machines in which there are a plurality of adjacent parallel casting lines. This arrangement is used more commonly in casting billets, the width and thickness of which are approximately equal, as opposed to casting relatively wide slabs.

An object of our invention is to provide an improved guide roll rack and supporting structure which locks the guide rolls accurately in the proper position, yet allows the rolls to be removed and replaced quickly and easily.

A further object is to provide an improved guide roll rack formed in sections which can be removed or installed individually without removing adjacent equipment above, below or to one side of the section.

A further object is to provide an improved guide roll rack and supporting structure which enable a single hoist mechanism to remove and replace guide roll racks of two parallel casting lines.

A more specific object is to provide an improved guide roll rack and supporting structure in which the rolls themselves are journaled in hingedly supported cages and the cages are supported to swing to positions enabling the handling mechanism to lift them bodily from the machine.

In the drawings:

FIG. 1 is a front elevational view of a portion of a continuous-casting machine equipped with guide roll racks and supporting structures constructed according to our invention,

FIG. 2 is an end elevational view from the left of FIG. 1;

FIG. 3 is a top plan view on a larger scale than FIGS. 1 and 2 of two of our roll racks and their supporting structure;

FIG. 4 is an end elevational view from the right of FIG. 3 on a still larger scale of one section of our roll rack and its hinge and lock assembly;

FIG. 5 is a vertical section on line V-V of FIG. 4; and

FIG. 6 is a vertical section on line VI-Vl of FIG. 4.

FIGS. 1 and 2 show portions of a multiple strand continuous-casting machine which includes two parallel guide roll racks l0 and 12. The racks are made up ofindividual sections 13. We show three sections 13 in each rack, but the number may vary. The supporting structure includes a fixed vertical column 14 located in front of the space between the two racks and a pair of

columns

15 and 16 located behind the'racks l0 and 12 respectively (FIG. 3). At their upper ends the columns support horizontal beams 17 which carry respective molds aligned with each roll rack, along with the usual associated equipment (not shown). Sets of power driven pinch rolls 18 (shown diagrammatically in FIGS. 1 and 2) are located below each roll rack. The usual spray means (not shown) is located around each roll rack. The molds, pinch rolls, spray means, etc. can be of any standard or desired construction suitable for continuous casting; hence we have not shown or described them in detail. The sections 13 of the roll racks are all of like construction, except that those of the roll rack 10 are of opposite hand from those of rack 12; hence we have described in detail only the uppermost section of rack 10 at the right.

As best shown in FIG. 3, each roll rack section 13 includes a rigid cage which is rectangular in plan and is formed of four vertically extending corner posts 22 and a plurality of horizontal connectors 23 welded to the posts. A plurality of sets of vertically spaced idler rolls 24 are journaled between the posts 22 and define a rectangular pass for confining a casting as it descends from the mold above.

As best shown in FIGS. 3 and 4, the flange of column 14 at the right carries upper and lower vertically extending

base plates

25 and 26 fixed thereto with bolts 27. We weld a pair of vertically spaced

hinge brackets

28 and 29 to the upper base plate 25 and another pair of vertically spaced

hinge brackets

30 and 31 to the lower base plate 26. We hinge an upper rackcarrying arm 34 between the two

upper hinge brackets

28 and 29 on a pin 35. Similarly we hinge a lower rack-carrying arm 36 between the two

lower hinge brackets

30 and 31 on a pin 37. Two of the horizontal connectors 23 near the upper and lower ends of the rack section project outside the confines of the cage and have

blocks

38 and 39 respectively welded thereto.

Blocks

38 and 39 carry depending pins 40 and 41 respectively which are removably received in

sockets

42 and 43 in the upper and

lower arms

34 and 36.

As shown in FIGS. 3, 4 and 5, one side face of the upper block 38 bears against a spacer pad 44 welded to the base plate 25. The bottom of the upper block has a spacer pad 45 welded to it and bearing against the upper face of arm 34. The bottom of arm 34 bears against a pair of spacer pads 46 welded to the hinge bracket 29. We weld a spacer pad 47 to the hinge bracket 28 overlying the arm 34. The arm may contact this pad when the rack section is lifted from the arms as hereinafter described. A bolt 48 extends through aligned openings in block 38, pin 40, spacer pad 44, base plate 25 and the flange of column 14. Another horizontal connector 23 near the upper end of the rack section projects outside the confines of the cage and has a plate 49 welded thereto (FIG. 3). The two projecting connectors 23 near the upper end lie at right angles to each other. Three bolts 51 extend through aligned openings in plate 49 and the flange of column 15. The middle bolt 51 also extends through the connector 23. Bolts 48 and 51 and the various spacer pads cooperate to lock the upper end of the roll rack 13 firmly in a fixed position. We interpose

shims

52 and 53 between column 14 and base plate 25 and between column 15 and plate 49 to position the upper end of the rack section accurately with respect to the structure above.

Each roll rack section undergoes significant thermal expansion and contraction in service, since it must handle castings which initially are at a temperature near the melting point of the metal. To allow for the resulting changes in vertical dimension of the section, we support their lower ends so that they are free to move up and down to the necessary extent. Pin 41 is freely movable vertically in its socket 43. There is clearance between the upper face of arm 36 and the lower face of block 39, as indicated at 55. Arm 36 rests on pads 56 welded to bracket 31, which normally carry only the weight of the arms alone. We weld a spacer pad 57 to the lower base plate 26. A bolt 58 extends through aligned openings in arm 36, pad 57, plate 26 and the flange of column 14. We insert shims 59 between arm 36 and pad 57 to position the lower end of the section accurately in the horizontal direction. We bolt the lower end of the rack section to column 15 in similar fashion to the upper end, except that the bolts 51a are shoulder bolts which permit the lower end to have limited vertical movement.

In operation, the construction explained thus far assures that the upper end of each rack section 13 normally is fixed in precise alignment with the structure above, and the lower end can move vertically as necessary. Thus the roll rack is operative to receive a partially solidified casting emerging from a mold and guide it in a vertical path to the pinch rolls 18, while the casting cools and continues to solidify. When it is necessary to remove a section of either roll rack or 12, we first remove

bolts

48, 51, 51a and 58 for that section. We then swing the rack section and its

arms

34 and 36 outwardly about pins 35 and 37 to a second position in which the section is out of the path ofthe casting and directly in front of column 14, as indicated in phantom lines in FIG. 3. The location of rack sections from either side of column 14 when they move to their second position is similar, as FIG. 2 shows. We equip the installation with a single hoist 60 which can engage a rack section 13 from either side of column 14 when the section is swung to its second position. The hoist can lower the rack section to a vehicle 61 below. We follow the reverse procedure in installing rack sections in the machine.

From the foregoing description, it is seen that our improved guide roll rack enables us to remove and replace rack sections quickly and easily without disturbing other equipment. Thus we have minimized the down-time of the continuous-casting machine for replacement of guide rolls. At the same time our rack construction assures that the guide rolls always are locked in the proper position with respect to other parts of the machine.

We claim:

1. in a continuous casting machine, a guide-roll rack and a supporting structure therefor;

said rack being formed of at least one section which comprises:

a rigid cage which is rectangular in plan and-has four corner posts and connectors fixed between each successive pair of adjacent posts; and

sets of idler rolls journaled between each successive pair of adjacent posts and defining a rectangular pass to encompass four sides of a casting traveling vertically through the cage;

said supporting structure comprising:

first and second vertical columns;

upper and lower hinge brackets fixed to said first column;

and

upper and lower rack-carrying arms hinged to the respective brackets;

pin-and-socket means adjacent one of said posts removably mounting said cage on said arms to move therewith when said arms swing about their hinged mounting on said brackets;

said cage being movable with said arms between a first position in which said rolls are operative to receive and guide a casting and a second position in which the cage is out of the path of the casting and can be lifted from said arms; and

releasable means engaging said columns normally locking said cage in said first position.

2. A machine as defined in claim 1 in which said rack is formed of a plurality of vertically aligned sections and said supporting structure comprises a corresponding number of upper and lower arms.

3. A machine as defined in claim 1 in which there are parallel racks and said supporting structure comprises a third vertical column, the arms which support said racks being swingable in opposite directions when moving from their first position to their second position, whereby the second positions of both racks are similar.

4. A machine as defined in claim 1 in which the means mounting said cage on said arms includes upper and lower blocks fixed to the cage outside the confines thereof and pins extending downwardly from the respective blocks, said arms having sockets removably receiving said pins.

5. A machine as defined in claim 1 in which said releasable means includes bolts removably connecting at least one of said arms to said first column and bolts removably connecting said cage to said second column.

6. A machine as defined in claim 1 in which said releasable means holds the upper end of said cage in a fixed vertical position but allows the lower end of said cage to move vertically as the cage undergoes thermal expansion or contraction.

7. machine as defined in claim 1 in WhlCh the means mounting said cage on said arms includes upper and lower blocks fixed to the cage outside the confines thereof and pins extending downwardly from the respective blocks, said arms having sockets removably receiving said pins, and in which said releasable means includes a bolt removably connecting said lower arm to said first column, a bolt removably connecting said upper block to said first column and passing through the pin which extends downwardly from said upper block, and bolts removably connecting said cage to said second column.

8. A machine as defined in claim 7 in which said lower block has clearance with respect to said lower arm and said first column to allow said cage to undergo thermal expansion and contraction.

9. A machine as defined in claim 1 in which a rack section can be removed without disturbing adjacent equipment.

Claims

1. In a continuous casting machine, a guide-roll rack and a supporting structure therefor; said rack being formed of at least one section which comprises: a rigid cage which is rectangular in plan and has four corner posts and connectors fixed between each successive pair of adjacent posts; and sets of idler rolls journaled between each successive pair of adjacent posts and defining a rectangular pass to encompass four sides of a casting traveling vertically through the cage; said supporting structure comprising: first and second vertical columns; upper and lower hinge brackets fixed to said first column; and upper and lower rack-carrying arms hinged to the respective brackets; pin-and-socket means adjacent one of said posts removably mounting said cage on said arms to move therewith when said arms swing about their hinged mounting on said brackets; said cage being movable with said arms between a first position in which said rolls are operative to receive and guide a casting and a second position in which the cage is out of the path of the casting and can be lifted from said arms; and releasabLe means engaging said columns normally locking said cage in said first position.

7. A machine as defined in claim 1 in which the means mounting said cage on said arms includes upper and lower blocks fixed to the cage outside the confines thereof and pins extending downwardly from the respective blocks, said arms having sockets removably receiving said pins, and in which said releasable means includes a bolt removably connecting said lower arm to said first column, a bolt removably connecting said upper block to said first column and passing through the pin which extends downwardly from said upper block, and bolts removably connecting said cage to said second column.