Abstract: Apparatus for exchanging a billet-guiding roller for another in a plant for continuous casting comprises a handling head, and two pivoted arms, each of which is pivoted to said handling head on an axis that is parallel or identical to the pivotal axis of the other of said pivoted arms. Each of said arms carries a holder for holding a billet-guiding roller. Said handling head also carries arm-driving means for pivotally moving each of said arms about its pivotal axis. In order to minimize the dimensions of said handling head, said pivoted arms have two inner ends, which are adjacent to each other and at which said arms are pivoted to said handling head, and outer ends, which are remote from each other and provided with said holders.

Abstract: A guide roll of the type which is provided with a ceramic sleeve around the circumference of a steel roll shaft with an internal cooling water passage, the guide roll including a cylindrical ceramic sleeve constituted by a multitude of discrete ceramic segments assembled into a number of annular unitary rings fitted around the circumference and along the length of the roll shaft, the individual ceramic segments being mounted in a restricted state at least in radial and circumferential directions of the roll shaft; and end plates securely fixed to the opposite ends of the roll shaft to grippingly hold the respective unit rings in an axially abutted state on the circumference of the roll shaft.

Abstract: A ceramic guide roll having a multitude of discrete ceramic segments cylindrically assembled around the circumference of a steel core shaft of the guide roll, the ceramic guide roll including a stopper member provided at a first end of the steel core shaft and a segment retainer attached to a second end of the steel core shaft opposite the first end through a resilient mechanism for holding the ceramic segments constantly in abutting engagement with each other in the axial direction of the steel core shaft in cooperation with the stopper member.

Abstract: A guide roll particularly suitable for conveying workpieces of high temperature, which: includes a steel core shaft internally provided with a cooling water passage along the axis thereof; a ceramic sleeve covering the circumference of the core shaft and constituted by a plurality of separable annular ceramic segments loosely fitted on and along the length of the core shaft; and fixing members for holding the respective annular ceramic in axially abutted state on the core shaft.

Abstract: A device for manufacturing metal strips by the roll casting process and having at least two rolls mounted in bearings in supporting frames is such that the supporting frames (5a and 5b) are connected by pre-tensioning facilities (E) each of which comprises a hydraulically or pneumatically powered cylinder-piston system. The said pre-tensioning facilities are mounted at one end on a pedestal base (10) running under the frame (5b) and at the other end on a cross beam (15) extending over the other supporting frame (5a).

Abstract: A continuous casting and rolling device of the type in which molten metal is introduced, by a nozzle, between a pair of liquid cooled rolls which are supported in a roll supporting structure and which each have a coolant connection and a drive which are disposed on different sides or ends of the roll supporting structure. Each roll is equipped with its own geared motor which is releasably fastened to the respective roll pin as a freely projecting drive unit.

Abstract: A continuous casting plant includes supporting elements following a through-type mould and including the strand guideways. The elements are arranged within a cooling chamber and are fastened to a supporting structure so as to be adjustable relative to the through-type mould and relative to one another in the direction transversely to the longitudinal axis of the strand guideways. In order to be able to carry out an aligned adjustment between the mould and the supporting elements in a simple manner, with little work to carry out and even with the plant in operation, wherein the entry of the cooling chamber is avoided, at least one of the supporting elements is coupled with an adjustment means. This adjustment means is fastened to a supporting structure, directed outwardly from the cooling chamber and actuatable from outside of the cooling chamber.

Abstract: A roll, for high temperature service in continuous slab casting, has having its sleeve shrinkage-fitted onto the roll shaft under tight contact state, wherein the alloy composition of the sleeve as expressed in % by weight is as follows.The principal components are:C: 0.20 or lessSi: 0.1 to 2.0Mn: 0.1 to 2.0Cr: 10 to 14N: 0.02 to 0.20; providedC+N: 0.30 to 0.35; andin addition to the principal components specified above, permissably one or more components beingNi: 0.1 to 5.0Mo: 0.1 to 2.0V: 0.01 to 0.3W: 0.1 to 0.3, andthe balance is Fe.

Abstract: An improved take-off device for a horizontal continuous-casting installation is provided. The arrangement comprises a frame and a mounting seated on rollers in the frame. The mounting is rotatable relative to the frame and supports the drive roll and its drive shaft, and a counter-pressure roll, which rolls preferably have counter-profiles corresponding to the cross section of the casting. The mounting comprises two concentrically arranged tubes which are sealed at their ends, thereby defining a cooling area therein. The adverse effects of gravity on casting quality may be mitigated by rotating the mounting relative to the frame, and locking it as a desired relative position, depending upon the cross-sectional configuration of the casting.

Abstract: A roll for transferring hot metal pieces having excellent corrosion resistance, oxidation resistance, crack resistance and a long service life has a surface layer part made of ferritic steel containing less than 0.1 percent by weight of carbon, 10.0-14.0 percent by weight of chromium, 0.4-1.0 percent by weight of columbium and the balance iron.

Abstract: To enable a segment of a cluster of bottom and top guide rolls to be readily replaced in a curved guide rack of a continuous casting installation, two fixed guide rails extend generally radially with respect to the curved guide rack at the two opposite sides of the guide roll support, rollers at opposite sides of the support engaging the guide rails for movement therealong, each guide rail including at least one portion inclined in relation to the generally radial direction of the guide rail and so disposed that, when the support is displaced along the guide rails, the support is pivoted into a skewed position which permits the support to pass between the two outer top guide rolls of two like segments adjacent thereto.

Abstract: During the continuous casting of preforms of large cross-section, considerable problems occur in the straightening region, because due to straightening, deformations are caused in the billet which has not yet solidified at the core. Therefore, in addition to the upper and lower straightening rollers additional lateral support rollers are provided, so that the billet is supported on all sides. For the purpose of space-saving incorporation in a multi-billet installation, the support rollers are mounted in swinging frames, which are moved by vertically raised cylinders. In order that the support rollers can be adapted to different billet dimensions, they are received within the fork-like swinging frames by vertically movable guide frames with roller supports inserted therein and able to be adjusted horizontally. Springs inserted in the swinging frames exert a continuous force in a vertical direction against the guide frames.

Abstract: An arrangement of coaxial neighbouring, mutually independently mounted strand guide rolls for use in a continuous casting installation for casting steel slabs is disclosed. At the region of the path of travel of the cast slab mutually neighbouring bearing or roll journals of two cooled strand guide rolls are interconnected by a coupling means which can be mounted upon the bearing or roll journals. The coupling means is provided with entrainment surfaces for the rotational movement of the guide rolls. These entrainment surfaces coact with the bearing or roll journals.

Abstract: In a supporting and guiding arc for cast strands including rollerways supporting the strand on opposite sides, the rollers are mounted on one-piece arcuate longitudinal carriers extending over the total length of the guiding arc. Transverse carriers are arranged in pairs opposite each other along the arcuate longitudinal carriers at a distance from one another, engaging the arcuate longitudinal carriers from behind and being connected by drawing anchors. In order to combine the advantages of guiding arcs assembled of segments arranged in series with the advantages of guiding arcs equipped with continuous arcuate longitudinal carriers, each rollerway has only two arcuate longitudinal carriers. A plurality of supporting segments are inserted between the arcuate longitudinal carriers and are detachably fastened to the same. A plurality of rollers allocated to a rollerway are journaled on each supporting segment.

Abstract: An alloy consisting essentially of, by weight, 0.1-0.6% C, up to 2.0% Si, 5.0-15.0% Mn, 5.0-15.0% Cr, 5.0-13.0% Ni, less than 1.0% V, and one or both of up to 1.0% Mo and up to 2.0% Nb, balance being substantially Fe and inevitable impurities. The alloy has outstanding nonmagnetic property, high hardness and good weldability, and particularly useful for electro-magnetic stirrer rolls in continuous casting machine.

Abstract: A rack-changing apparatus for a continuous casting installation, especially for changing the curved guide, support and cooling racks of a continuous casting installation having a plurality of casting lines, has a carriage which is shiftable transversely to the casting lines on rails mounting below the casting floor and preferably extending beyond the installation to a location at which the racks can be deposited and picked up. An arm on the carriage is swingable in a vertical plane about a horizontal axis and is extensible and retractable while carrying on its end a clamping mechanism swingable in a vertical plane about a horizontal axis at the arm end for engagement with the racks.

Abstract: A bow-type continuous casting plant includes a strand bending arrangement arranged below the mould, and a circular-arc guide for the strand following thereupon. The circular-arc guide has oppositely arranged supporting roller ways, and the bending arrangement includes two oppositely arranged bow-structure parts carrying bending and supporting rollers each, and being supported on each other. The distance of the supporting-roller ways of the circular-arc guide is variable in accordance with the strand cross section to be adjusted. One of the bow-structure parts of the bending arrangement is provided with exchangeable roller carriers detachably fastened to it and adapted to different strand cross-sectional formats with their dimensions.

Abstract: In a strand guiding stand including oppositely arranged stand parts connected by drawing anchors and on which strand guiding rollers are journaled, at least one of the stand parts is displaceable, and fixable, by a displacement device along the drawing anchors. The displacement device includes at least one bushing on each drawing anchor, with a helical supporting surface. Each bushing leans against a fixed abutment of the drawing anchor and the displaceable stand part is supported on the bushing. In order to prevent a change in the distance of the oppositely arranged strand guiding rollers and to be able to adjust the distance automatically merely by rotating the bushings, the helical supporting surface of each bushing has an angle of inclination that is larger than the pertaining angle of friction.

Abstract: A transport apparatus comprising a plurality of metal rolls for transporting a hot heavy material is disclosed. Each roll is provided with a desired number of ring-like circumferential grooves which are filled with a heat insulating material, and the grooves of each roll are staggered with respect to the grooves of the adjacent rolls. In accordance with the present invention, the temperature drop of the hot heavy material during the transportation can be greatly reduced, and in addition, the temperature fluctuation in both the sectional direction and the longitudinal direction of the hot heavy material is sharply decreased. The invention contributes considerably to the realization of the direct rolling process on an industrial scale.

Abstract: A method and apparatus for the cooling of a continuously cast metal strand, comprising a plurality of support rollers, located in the second zone of cooling. The support rollers are cooled from their interior by the passage therethrough of cooling fluid. The rollers have interior walls which display a wave-like shape to present a great surface area for superior cooling while still supporting the loading stress due to the weight of the metallic strand.

Abstract: A continuous casting roll comprises a roll body having a cooling water bore coaxially therewith, and a sleeve fitted around the roll body and having one end fixed to the roll body and the other end as a free end. The roll body has a trunk portion and a shaft portion at each end of the trunk portion. A plurality of cooling water channels provided between the trunk portion and the sleeve extend in parallel axially thereof and have opposite ends in communication with the water bore. The sleeve is fitted around the roll body by a shrink fit the interference of which decreases steadily from the fixed end toward the free end to permit free thermal deformation of the sleeve toward the free end.

Abstract: An alloy comprising, by weight, 0.1-0.6% C, up to 2% Si, 5-15% Mn, 5-15% Cr, 5-13% Ni, 1-3% V, and at least one of up to 1% Mo and up to 2% Nb, the balance being substantially Fe and inevitable impurities. The alloy has an outstanding non-magnetic property of up to about 1.004 in magnetic permeability and high hardness of above about 215 in Vickers hardness and is useful for electromagnetic stirrer rolls for continuous casting equipment.

Abstract: In continuous casting equipment having a path of transport of castings defined by roll segments and having a curved section and a horizontal section, an apparatus for hoisting the roll segment comprises a pair of pivotal guide rods pivotably supported by a trolley disposed above the horizontal section, a pair of fixed guide rods arranged on the opposite sides of each of the roll segments defining the curved section, and a pair of fixed circular arc rails extending along the paths of movement of the free ends of the pivotal guide rods. A truck, movable on the rails and engageable with the pivotal guide rods, is reciprocatable along the rails to align the pivotal guide rods with a desired pair of fixed guide rods for hoisting the corresponding roll segment along the fixed guide rods to the pivotal guide rods in alignment therewith.

Abstract: A roller apron or strand guide arrangement for the withdrawal and/or straightening region of a continuous casting installation for the casting of strands contains two roll tracks subdivided into sections or segments containing at least two rolls for each roll track. The rolls of each track section are mounted upon a respective traverse or yoke, with the one traverse being affixed to a frame and the other traverse is hingedly connected at piston rod heads of stationarily arranged pressurized fluid medium cylinders. The piston rod heads are associated with guides at stands, the guides extending transversely with respect to the roll tracks. The guides are arranged between the roll sections at regions of parting lines between the sections and each roll section at each side of the path of travel of the cast strand possesses two pressurized fluid medium cylinders whose piston rod heads are guided at one side along a respective one of the guides.

Abstract: In a supporting and guiding structure for a continuous casting plant, roller ways supporting the strand on two opposite sides are provided, one of the two roller ways being arranged on a first supporting framework and the other roller way being arranged on the second supporting framework which is braceable relative to the first supporting framework by drawing anchors and is connectable with the first supporting framework and detachable therefrom. In order to be able to effect the connection and release by parts that are easy to handle, a bayonet connection is provided as the connection between supporting framework and drawing anchors. The bayonet connection includes a disc having at least one recess and arranged on the supporting framework. A drawing-anchor head including a lateral neck that corresponds to this recess is insertable into the recess, and the drawing-anchor head or the disc is rotatable into a fastening position axially fixing the drawing anchor.

Abstract: A strand guide for an arcuate continuous casting plant has at least one arcuate, horizontally displaceable supporting and guiding structure. In order to be able to remove and install the supporting and guiding structure in a simple manner, on ensuring a good accessibility and not restricting the space on the casting platform, the supporting and guiding structure is mounted on at least one intermediate trestle. The intermediate trestle is adjustable in the arc plane and is supported on at least one supporting trestle which is adjustable transversely to the arc plane.

Abstract: A roll for guiding a cast metal strand emanating from a continuous casting machine comprises a cylindrical envelop rotatable about its axis by contact with the cast metal strand. A pair of tubular spindles project from opposite ends of the envelop coaxially fixed thereto and rotably mounted in the region of the outer ends in ball bearings fixed to the machine frame. A central tubular arbor equiped in a central portion thereof with an inductor extends with radial clearance through the spindles and is supported at end portions thereof projecting beyond the spindles in cradles fixed to the machine frame. A key or the like is provided in one of the cradles engaging in a cutout of the central arbor to prevent rotation of the latter during rotation of the envelop and the spindles connected thereto.

Abstract: An apparatus for blocking escaped heat in hot slabs manufactured on a continuous-casting machine. The apparatus has a heat containing cover extending in the longitudinal direction of the slab on both sides of the withdrawal guide rolls. The upper and lower portions of the heat containing cover each have a semi-circular cut to receive the lower part of a top guide roll and the upper part of a bottom guide roll. The heat containing cover can be reciprocated in the direction of the axis of the guide rolls so that a desired clearance is left between the cover and the edges of the slab.

Abstract: In a driving roller stand for continuous casting plants with at least two adjacently arranged strand guides, at least one separately arranged driving roller is provided for each of the strands. A first driving roller is designed as a hollow construction unit with a first driving element. A driving shaft provided with a second driving element, of a second driving roller coaxially arranged with the first one penetrates this hollow construction unit. Each of the driving rollers is separately arranged on the driving roller stand. In order to be able to arrange the strands as closely adjacent as possible in such a driving roller stand, the driving shaft is engageable out of and in both the second driving roller and the second driving element and is axially removable out of and installable into the hollow construction unit of the first driving roller.

Abstract: A supporting and guiding stand for continuous casting plants comprises roller ways supporting the stand on two opposite sides. One of the roller ways is arranged on a first supporting framework and the other roller way is arranged on a second supporting framework braceable relative to the first supporting framework by means of a number of drawing anchors and connectable to the same. Adjustment drives are provided for adjusting the second supporting framework relative to the first supporting framework.

Abstract: Rollers used in roller aprons, which support and guide the metal strand formed in a continuous casting mold, are made of a fixed shaft and elongated roller sleeve sections which are rotatably mounted upon the shaft. The shafts are fastened upon spaced apart rails secured to support plates. Bearings are arranged between the ends of each sleeve section and its shaft. Each bearing comprises a journal type bearing part and a thrust type bearing part. The journal type bearing part includes a cylindrical bronze sleeve non-rotatably fitted within its roller section end. A "Teflon", bronze impregnated, thin wall liner bushing is fitted within a wide recess formed in the interior wall of the outer end of the bronze sleeve to thereby form about one-half of the journal bearing inner wall surface which is arranged in rotatable contact with its shaft.

Abstract: In a continuous casting installation, screw-less fixing of the roller guide segment frames to the bed is achieved by means of a plurality of traction rods which can be subjected to traction force by hydraulic means. Each traction rod has a nut thereon which is loadable by a respective ring piston guided in a self-adjusting manner in a semi-cylindrical bearing member supported on the bed. The free end of the traction rod is an apertured head aligned with frame apertures. A locking pin passing through said apertures releasably interconnects the rod and the segment frame.

Abstract: A supporting and guiding stand for a bow-type continuous casting plant comprises exchangeable supporting segments in which the rollers of the oppositely arranged inner and outer guideways are mounted at a distance from one another. The segments are supported on a carrying frame, which advantageously is dividedly designed. On each segment at least one rim-side roller of the outer guideway is detachably fastened to the segment.

Abstract: The continuous casting installation is provided with freely rolling rollers which can be releaseably coupled to drive motors to impart a pushing force on the moving slab. The drive motors are mounted on slides which are reciprocated by a piston-cylinder unit. Also, each drive motor can be reciprocated toward and away from a facing roll by another piston-cylinder unit.

Abstract: The freely rolling rolls are provided with distance wheels at the respective ends. Alternating rolls are provided with distance wheels which are fixedly mounted to the roll bodies while the remaining rolls are provided with distance wheels which are rotatably mounted on the roll bodies. The adjacent distance wheels are also provided with interengaging V-shaped grooves and projections for lateral stability of the rolls. The distance wheels provide for a constant uniform spacing of the rolls and maintain the rolls in parallel relation.

Abstract: A strand guide for a continuous casting plant includes oppositely arranged rollers for supporting and guiding the strand. The axes or shafts of the rollers are detachably fastened to longitudinal carriers of a strand guiding stand. The longitudinal carriers are arranged between holding means supporting the axes of at least two pairs of oppositely arranged rollers, and the holding means of these oppositely arranged rollers are clamped relative to each other by centrally positioned clamping means.

Abstract: In order to improve disassembly of the oscillation mechanism at a continuous casting installation, the continuous casting mold and the first support guide zone, and at the same time to obtain a support guide arrangement free of dislocation at the transition location, an upper section of the machine base frame and a support frame for the mold and the first zone of the support guide arrangement are at least partially overlappingly arranged. The underside of the frames are supported upon a foundation which is common to such frames. The upper section or portion of the machine base frame at its upper end region and the support frame for the continuous casting mold are movably supported in the direction of travel of the continuously cast strand at a common support location.

Abstract: A supporting and guiding stand for a bow-type continuous casting plant comprises exchangeable supporting segments supported on a carrying frame, in which segments the rollers of the oppositely arranged inner and outer guideways are mounted at a distance from one another. In the center of the circular arc along which the supporting segments are arranged, a pivoting lever including a device for seizing and extracting individual supporting segments is mounted. The length of the lever is shorter than the radial distance from the center to the supporting segments. For removing a desired supporting segment, telescopically extendable and retractable guide rails are provided on the pivoting lever, which, after having been moved out into the strand guideway, seize a supporting segment in a fork-like manner. Upon seizure counter guides arranged on the supporting segment come into engagement with the guide rails, the supporting segment thus being removable from the installed position along the guide rails.

Abstract: The present invention is used in continuous casting machines where a billet is withdrawn from a mould and simultaneously rotated about its own axis. The invention provides a withdrawal roll unit that has withdrawal rolls mounted on oscillating levers or housings cantilevered on a rotating cage. The levers, with the withdrawal rolls, are located in a plane perpendicular to the axis of rotation of the cage. The ends of the levers are connected in series one to another. In one embodiment, a second end of each lever or housing is connected by an elastic element to a first end of an adjacent lever which, in turn, is secured to the cage.

Abstract: The drawing and straightening machine for use in continuous casting plants, comprises a first pair of superposed pinch rolls, arranged at the bottom end of the curved guide path section, passing through which the casting is bent, and a second pair of pinch rollers arranged subsequently to the first pair. The second pair of pinch rollers is mounted on the machine frame so as to be capable of swinging from an upper starting position, at which the rolls are operatively arranged on the curvilinear upwardly directed prosecution of the curved path of the casting, to a lower straightening position, at which the rolls are in alignment with the rectilinear guide section onto which the straightened casting moves for further processing. Each roll of the second pair of rolls is mounted on a roll-carrier, and each roll-carrier is hinged to the machine frame around a single common fulcrum axis.

Abstract: A guiding stand to be used in a continuous casting plant includes rollers supporting the strand at opposite sides and arranged in a supporting framework. The rollers, at least at one side of the strand, are mounted in guide rods pivotably arranged in the supporting framework for adjustment to various strand thicknesses. The guide rods are pivotable by an adjustment device, and the guide rods of neighboring rollers are each connected with one another by coupling rods in the manner of a four-bar linkage.

Abstract: A driving roll stand to be used in a continuous casting plant includes a lower roll and an upper roll arranged one above the other. At least one of the rollers is drivable by a rotary drive. The lower roll is mounted at a support supported on a base, and the upper roll is mounted at a lever hinged to the support and pivotably movable by an adjustment drive. The adjustment drive is hinged both to an upper part of the support rising above the lever in height and to the lever. Further the rotary drive of the upper and/or lower roll is mounted at this upper part of the support.

Abstract: A shear plug particularly for use in combination with a load cell in the roll-rack of a continuous-casting machine. The plug includes a body which has a shallow recess in one face and an axially aligned and preferably deeper recess in the other face, and a wall separating the recesses. The shallow recess receives the end of a load cell of smaller dimensions. On application of an overload the load cell punches out a tapered segment from the wall. The plug does not expand sideways when it fails and is readily removed from the surrounding mechanism.

Abstract: A pressure release device is provided for metal strand casting plants to relieve the pressure between opposed sets of supporting rolls for the strand in instances where unusual pressure build-up takes place between the opposed sets of rolls. The device is simple and inexpensive and may be positioned in the axis of the connecting rods between two opposed roll stands. The device accommodates a regular mechanical spindle-threaded nut spacing arrangement, which may be manually adjusted and avoids the problem of "freezing" which is common with such devices using a "built-in" frictional release arrangement.

Abstract: A device for handling semi-continuously vertically cast rectangular strands, especially of aluminum and aluminum alloys. The strands are simultaneously adjacent to each other lowered by means of a downwardly movable casting table, brought into engagement with a supporting member, and by a pivoting movement of the dummy bars and of the supporting member which are operatively connected to the casting table are moved into an at least nearly horizontal positon with regard to the casting table. The above mentioned pivoting movement is coupled to the upward movement of the casting table. The strands are cast in such a way that one of their narrow sides is located opposite the supporting member. During the upward movement of the casting table, the supporting member with the strands one narrow side of which engages the supporting member are pivoted about a pivot axis which is eccentrically located with regard to the longitudinal plane of symmetry of the casting table.

Abstract: A strand guide arrangement to be used in a continuous casting plant has a frame displaceable by an adjustment drive, on which frame supporting elements are mounted which are adjustable to one side face of the strand. The frame is detachably fastened to a displacement ruler and is removable vertically upwardly after release of the fastening and retraction of the displacement ruler. The frame is connectable with the displacement ruler by a projection mounted on the frame or on the displacement ruler and insertable into a corresponding recess in the displacement ruler or in the frame, respectively.

Abstract: A strand guiding stand to be used in a continuous casting plant has longitudinal beams and cross beams forming a cage-like carrying structure. Strand guiding rollers having roller axles are mounted in this cage-like carrying structure. Roller holding means accommodate the roller axles and thereby fasten the strand guiding rollers of each side of the strand guiding stand directly to the longitudinal beams, independently of the cross beams.

Abstract: The invention covers a supporting roller stand for steel slab strand casting plants, particularly for curved slab strand casting plants with supporting rollers of differential lengths being arranged opposite, in pairs, along the broad sides of the strand profile, subdivided on at least one side over the width of the strand, such supporting rollers being furthermore arranged in groups of differential diameters.

Abstract: A roller apron for a continuous casting installation, especially for casting steel strands, for supporting a partially solidified strand, which comprises a number of successive pairs of rolls which follow one another in the direction of travel of the strand. The bearings of at least one roll are arranged at a traverse or crosshead extending essentially parallel to the lengthwise axes of the rolls. The traverse can be applied against stops governing the format or cross-sectional thickness of the strand and coacting at both ends with pivotable levers articulated at the machine frame and at a movement device. The movement device comprises a power source interconnecting both of the pivotable levers.

Abstract: A segment exchanger apparatus for a continuous casting installation and a method of operating the same is disclosed, wherein there is provided an at least partially curved strand guide or roller apron subdivided into segments. The segments are mounted in stationary, straight guides. It is possible to pull any selected segment, by means of a flexible traction element operated by a stationary crane or equivalent structure, out of its stationary guide and through an inner pivotable track section. A replacement segment can be introduced, through the inner track section, into the stationary guide.