US3913658A

US3913658A - Adjustable plate mold for continuous casting

Info

Publication number: US3913658A
Application number: US337442A
Authority: US
Inventors: Markus Schmid
Original assignee: Concast AG
Current assignee: SMS Concast AG
Priority date: 1972-03-03
Filing date: 1973-03-02
Publication date: 1975-10-21
Anticipated expiration: 1992-10-21
Also published as: USB337442I5; NL7302961A; FR2174965A1; CA979619A; FR2174965B1; NL153454B; DE2310615C3; JPS48102037A; DE2310615A1; CH544598A; GB1421202A; ZA731469B; JPS5229964B2; DE2310615B2; IT981078B

Abstract

An adjustable plate mold for continuous casting incorporating a support frame and longitudinal walls and transverse walls supported at the support frame, said longitudinal walls and transverse walls limiting the mold compartment. The longitudinal walls are slidingly arranged at the side facing away from the hollow mold compartment upon support plates for expansion and contraction and the transverse walls are equipped with adjustment devices supported by the support frame. The adjustment devices positively are connected, on the one hand, with the transverse walls and, on the other hand, with the support frame in the adjustment directions. Exchangeable impact or stop gauges corresponding to the momentary reference value of a mold dimension are provided between the transverse walls and impact or stop surfaces at the support frame and the transverse walls can be fixedly clamped between the longitudinal walls. Each adjustment device has associated therewith a coupling for interrupting the positive connection. During the casting operation this coupling permits movement of the associated fixedly clamped transverse wall with respect to the impact surfaces in the direction of the mold compartment and back again.

Description

Schmid [451 Oct. 21, 1975 ADJUSTABLE PLATE MOLD FOR CONTINUOUS CASTING [75] Inventor: Markus Schmid, Zurich, Switzerland [73] Assignee: Concast AG, Zurich, Switzerland [22] Filed: Mar. 2, 1973 [21] Appl. No.: 337,442

[44] Published under the Trial Voluntary Protest Program on January 28, 1975 as document no.

[30] Foreign Application Priority Data Mar. 3, 1972 Switzerland 3114/72 [52] US. Cl. 164/280 [51] Int. Cl. B22d 11/00 [58] Field of Search 164/280, 273, 277, 2, 4

[56] References Cited UNITED STATES PATENTS 2,893,080 7/1959 Goss 164/280 3,015,862 1/1962 Rustemeyer et al. 164/277 3,292,216 12/1966 Colombo 164/273 R 3,710,845 1/1973 Burkhardt et al 164/273 3,735,801 5/1973 Burkhardt 164/273 R 3,777,436 12/1973 Bode, Jr 164/273 R Primary Examiner-Andrew R. Juhasz Assistant Examiner-V. K. Rising Attorney, Agent, or Firm-Werner W. Kleeman [57 ABSTRACT An adjustable plate mold for continuous casting incorporating a support frame and longitudinal walls and transverse walls supported at the support frame, said longitudinal walls and transverse walls limiting the mold compartment. The longitudinal walls are slidingly arranged at the side facing away from the hollow mold compartment upon support plates for expansion and contraction and the transverse walls are equipped with adjustment devices supported by the support frame. The adjustment devices positively are connected, on the one hand, with the transverse walls and, on the other hand, with the support frame in the adjustment directions. Exchangeable impact or stop gauges corresponding to the momentary reference value of a mold dimension are provided between the transverse walls and impact or stop surfaces at the support frame and the transverse walls can be fixedly clamped between the longitudinal walls. Each adjustment device has associated therewith a coupling for interrupting the positive connection. During the casting operation this coupling permits movement of the associated fixedly clamped transverse wall with respect to the impact surfaces in the direction of the mold compartment and back again.

7 Claims, 4 Drawing Figures ADJUSTABLE PLATE MOLD FOR CONTINUOUS CASTING BACKGROUND OF THE INVENTION limiting the mold compartment or cavity.

During continuous casting, especially during the continuous casting of steel into slabs or ingots, there are employed adjustable plate molds. By displacing the transverse walls of such molds it is possible to vary the width of the strand format or by exchanging the transverse walls for others having a different dimension it is possible to vary the thickness of the strand. Adjustment devices are arranged between these transverse walls and the support frame for the rapid and exact adjustment of these transverse walls. As a general rule such adjustment devices consist of threaded spindles which are hingedly connected with the transverse wall and by threading or worm gears with the support frame. Connections such as hinges, threads and worms or the like provide a positive connection in the axial direction of the spindle. The use of such adjustment devices is a prerequisite for realizing a mechanized orautomated adjustment. 7

During the casting operation, especially at the start of the casting, the walls of the mold heat-up. As a result thereof there is formed throughout the walls a temperature gradient between the sides confronting the hollow mold compartment and the cooled wall sides facing away from such hollow mold compartment. Such temperature gradient produces stresses at the walls of the mold, resulting in expansion and contraction phenomena. In the case of adjustable type molds, the transverse walls of which are connected through the agency of adjustment devices with the support frame and supported thereat during expansion of the longitudinal walls at the start of casting or during contraction of such walls upon the completion of the casting operation there occurs relative movement between the transverse walls and the longitudinal walls at the joints. These relative movements are repetitive during each casting operation and therefore produce, on the one hand, scratch marks at the longitudinal walls and, on the other hand, wear at the joint surfaces of the transverse walls. The presence of these scratch marks at the longitudinal walls within the hollow mold compartment can, in turn, produce surface defects at the cast product or strand and additionally reduce the longevity of the mold. The wear phenomena noted above produces, during subsequent adjustment, gaps at the joints which permit penetration of the liquid steel and therefore promote the danger of metal break-out.

Now the state-of-the-art is familiar with plate molds in which the longitudinal walls, at the side facing away from the hollow mold compartment, are arranged at support plates such that they can slide in a manner that after overcoming the prevailing friction they can expand and contract. By means of tension boltsuconnected with the transverse walls, and which are mounted free of play in bores of the longitudinal walls formed of copper, the transverse walls are fixedly clamped. During expansion and contraction of the longitudinal walls the transverse walls move together with the longitudinal walls and there is thus prevented relative movement between the longitudinaland transverse walls at the joints. Such molds possess the drawback that owing to the irregular expansion of the longitudinal walls the mold reference value i.e. the desired mold dimension during casting operation and the reference taper of the transverse walls can change in an uncontrolled fashion after the mold adjustment and therefore cause defects in the cast strand. When using such molds there is, however, needed for each desired strand format a corresponding mold, which requires high investment cost. Additionally, owing to the required exchange of the mold when carrying out a change in the format or shape of the cast strand there is also increased the downtime of the continuous casting installation.

There is also known to the art an adjustable plate mold which consists of a support frame and longitudinaland transverse walls equipped with cooling devices and supported at the support frame. The transverse walls are provided with adjustment devices supported at the support frame. Between the transverse walls and stop or impact surfaces at the support frame there are provided exchangeable stop or impact gauges corresponding to the mold reference dimension and the reference taper. The transverse walls are fixedly clampable between the longitudinal walls. At the start of casting or at the end of casting respectively there occur at such molds, at the joints between the transverse walls and the longitudinal walls which respectively expand and contract, relative movements which subject these longitudinaland transverse walls to wear. Owing to this wear the quality of the surface of the cast strand is impaired and additionally the useful life of the mold is shortened.

SUMMARY OF THE INVENTION Hence from what has been discussed above it should be apparent that this particular field of technology is still in need of an adjustable plate mold for continuous casting which is not associated with the aforementioned drawbacks and limitations of the prior art proposals. Accordingly, it is a primary object of the present invention to provide a new and improved construction of adjustable plate mold for continuous casting which effectively and reliably fulfulls the existing need in the art and is not associated with the aforementioned drawbacks and limitations of the state-of-the-art proposals.

Another and more specific object of the present invention aims at, on the one hand, rigidly supporting the transverse walls for predetermined mold reference dimensions at the support frame by means of adjustment devices, and, on the other hand, reducing the wear at the mold walls as well as avoiding strand defects caused by the mold.

Yet a further significant object of the present invention relates to a new and improved construction of adjustable plate mold which is relatively simple in design, extremely reliable in operation, quite easy to set-up and use, subject to lesser wear than was the case for existing state-of-the-art plate mold constructions, and permits accurate and easy adjustment of the transverse walls of the mold to alter the format or dimensions of the cast strand.

supportframe. Each of these adjustment devices is positively connected, on the one hand, with its associated transverse wall and, on the other hand, with the'support frame in the mold adjustment directions of the transverse walls. Further, exchangeable stop or impact gauges corresponding to the momentary reference value'of a mold dimension i.e.,'the-desired mold dimension during casting are provided between the transverse walls and stop or impact surfaces at the support frame, and the transverse walls can be fixedly clamped between the longitudinal' walls. According to important aspects of the invention a coupling for interrupting the connection between the. transverse wall and the support frame is operatively associated with each adjustment device and this coupling, during the casting operation, permits movement of the fixedly clamped transverse wall with .respect tothe stop surfaces in the direction of the hollow mold compartment and back again.

*With the apparatus of the invention under discussion it isposs ible to rapidly and exactly adjust and rigidly support the mold with'respect to the mold reference dimension and the reference taper. corresponding to the operatin'gor thermal conditions and at the same time appreciably reduce wear at the joints of the mold walls. In this way there is minimized surface defects at the strand which otherwise are caused by the mold, and at the sametime mold longevity is increased.

- Depending upon the construction and the available space the coupling for'interrupting the'positive connection between the associatedtransverse wall and the support frame can be advantageously arranged between the adjustment device and the support'frame or the adjustmentdevice and the-transverse wall.

Inthe case of molds having a spindle type adjustment device the coupling is advantageously designed in such a way that a disk'which is connected in a positive fashion via threads with the spindle can be slidingly guided at the support frame axially with respect to the spindle and that between a support surface of the support frame and 'the disk there is arranged a pre-biased package of springs in-such a way that the spring force urges the associated transverse wall against the stop or impact gauges.

In order that the transverse walls can move freely together with the longitudinal walls during heating and cooling of the mold it is contemplated, according to a further aspect of the invention, that the coupling consists of a coupling element which cooperates with the spindle for selectively separating and connecting the spindle with the corresponding-transverse wall or the support frame.

BRIEFDESCRIPTION OF THE DRAWINGS The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof; Such description makesreference to the annexed drawings wherein:

FIG. 1 is a top plan view of a partially sectionally il lustrated plate mold in hot condition, in other words when subjected to thermal action;-

FlG.2 is aplan view ofithe mold of FIG. 1 in cold condition;

FIG. 3 is'a plan view of'a different embodiment of partially depicted mold; and

FIG. 4 is a sectional view of the mold construction of FIG. 3, taken substantially along the line IV-IV thereof, and turnedi-in the plan of-the drawing.

DETAILED DESCRIPTIQN or THEIREFERRED EMBODIMENTS v Describing now thedrawings, in FIG. 1 longitudinally 5 extending walls 3 and transversely extending walls 4 ,(only oneof the transverse walls 4 has, been shown) which delimit a mold compartment-or cavity 2 are supportedupon a support frame 1 which extends completely about-a mold 6. The longitudinal extending or longitudinal walls3 are slidingly arranged at the side facing away from the mold compartment 2 upon sup-' port plates v5 in such a manner thatafter overcoming the prevailing friction-they can expand and contract. Between the support plates 5 and the

mold walls

3 and 4 there are provided cooling 'devices 7. The transversely extending or transverse walls 4 are adjustable .by means of the spindles 8.:Each of these spindles 8 is associated with one of the transverse walls and they are supported at the support frame 1 and equipped with a suitable and therefore not particularly illustrated drive.

Since the spindle-adjustment devices may be the same for each of the transversewalls 4 the description will be convenientlyv defined to one of the transverse walls and 1 its associated adjustment device. Between the support .plates ofthe' transverse walls 4 and the support frame 1 there are arranged exchangeable stop or impact gauges 11 accommodatedto an associated mold refer ence dimension 9 corresponding to. the width of the strand and an associated reference taper. The transversewalls 4'can be fixedly clamped betweenthe longisprings 14, which cooperates with the disk 18, serves as.

an elastic coupling and interrupts the positive connection acting in the mold adjustment directions 15 between the associatedtransverse wall 4 and the support frame 1.

FIG. '1 depicts the mold 6 in its hot condition or directly after there has been undertaken an adjustment of I the format or dimension of the strand. Under the thermal action of the cast metal the

mold walls

3 and 4 expand, especially the longitudinal walls 3. In the case of molds for slab widths in the range of two meters expansions in the order of about 3 millimeters have been measured at the copper longitudinal walls. Only at the beginning of thefirst casting following a strand format adjustment does thereoccura relative movement between the rigidly supported transverse walls 4 and the expanding longitudinal walls 3,,and which corresponds in magnitude to the maximum possible expansion of the longitudinal walls. During cooling of the mold walls,

after termination of the casting operation, the longitudinal walls 3 again contract and entrain the transverse walls 4 which are fixedly clamped between the longitudinal walls in the direction of the mold compartment or cavity 2 while compressing the package of springs 14 by an amount which corresponds to the expansion which has occurred at the start of casting.

In FIG. 2 the mold 6 is shown in its cold condition. The set or package of springs 14 and the slidingly guided disk 18 render possible movement of the spindle 8 in axial direction and therefore a movement of the associated fixedly clamped transverse wall 4 away from the stop or impact surfaces 19 in the direction of the mold compartment 2. By means of the disk 18 the package of springs 14 can be pre-biased to the desired degree. Between the stop or impact gauges ll suspended at the associated transverse wall 4 and the associated stop or impact surfaces 19 there is formed a gap 20 corresponding to the contraction of the longitudinal walls 3. Due to a re-heating of the mold 6 during the next casting operation this gap 20 closes upon reaching the maximum expansion of the longitudinal walls 3, so that no further relative movement can occur between such walls 3 and the transverse wall 4, yet the mold reference size or dimension remains constant for each casting.

Although with the arrangement of FIGS. 1 and 2 there has been provided for the adjustment element 8 an elastic coupling for interrupting the positive connection, in the embodiment of FIGS. 3 and 4 there is depicted a different solution for interrupting this connection. Reference character 21 designates another spindle for adjusting the associated transverse wall 4 and which can move such transverse wall 4 in the adjustment directions 15. By means of a movable coupling bolt 22 cooperating with the spindle 21 there can be selectively established or interrupted a positive connection which acts in the adjustment directions, between the transverse wall 4 and the spindle 21.' During a strand format adjustment the coupling bolt 22 is coupled-in or engaged in the manner depicted in FIG. 4. .After fixedly clamping the transverse walls 4 between the longitudinal walls 3 the coupling bolt 22 is raised i.e., pulled out and therefore the connection between the associated transverse wall 4 and the support frame 1 is disconnected. This renders possible movement of the transverse wall 4 away from the stops 19 in the direction of the mold compartment 2 and back again. ln FIGS. 3 and 4 the coupling 22 is arranged between the spindle 21 and the associated transverse wall 4. Depending upon the available space such coupling can be, however, also installed between the spindle 21 and the support frame 1.

While there is shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following claims. Accordingly,

I claim:

1. An adjustable plate mold for continuous casting, comprising a support frame having stop surface means, a mold formed by longitudinal walls and transverse walls for limiting a mold compartment thereof, said mold being provided with cooling devices, said longitudinal walls and transverse walls being supported by the support frame, support plates upon which the longitudinal walls are slidingly arranged at the side facing away from the mold compartment for expansion and contraction, adjustment devices provided for the transverse walls, said adjustment devices being supported by the support frame, said adjustment devices being connected with the associated transverse wall and with the support frame, exchangeable stop gauges provided be tween the transverse walls and the stop surface means at the support frame, said exchangeable stop gauges corresponding to a desired mold dimension during casting operation, said transverse walls being fixedly clampable between the longitudinal walls, coupling means operatively associated with each adjustment device for interrupting the connection between the associated transverse wall and the support frame, said coupling means during the casting operation permitting movement of the associated fixedly clamped transverse wall with respect to the stop surface means in the direction of the mold compartment and back again.

2. The mold as defined in claim 1, wherein said coupling means is arranged between the associated adjustment device and the support frame.

3. The mold as defined in claim 1, wherein said coupling means is arranged between the associated adjustment device and transverse wall.

4. The mold as defined in claim 2, wherein the support frame has a supporting surface, the adjustment device being a spindle adjustment device incorporating a spindle, a disk threadably connected with the spindle, said disk being slidingly supported at the support frame in the axial direction with respect to the spindle, a prebiased package of springs arranged between the supporting surface of the support frame and said disk such that the spring force presses the associated transverse wall towards the stop gauges.

5. The mold as defined in claim 2, wherein the adjustment device is a spindle adjustment device having a spindle, said coupling means comprising a coupling element cooperating with the spindlefor selectively disconnecting and connecting the spindle with the associ ated transverse wall.

6. The mold as defined in claim 3, wherein the adjustment device is a spindle adjustment device having a spindle, and said coupling means comprises a coupling element cooperating with the spindle for selectively disconnecting or connecting the spindle with the associated transverse wall.

7. In an adjustable plate mold for continuous casting, comprising a support frame having at least one stop surface, a mold formed by longitudinal walls and transverse walls clamped between the longitudinal walls for limiting a mold compartment thereof, said longitudinal walls and transverse walls being supported by the support frame, adjustment means provided for at least one of the transverse walls, said adjustment means being supported by the support frame, said adjustment means being connected with said at least one transverse wall and with the support frame, exchangeable stop gauge means provided between said at least one transverse wall and the stop surface, and coupling means provided for said adjustment means for interrupting the connection between said at least one transverse wall and the support frame, said coupling means during the casting operation allowing for movement of said at least one transverse wall with respect to the stop surface in the direction of the mold compartment and back again.

Claims

1. An adjustable plate mold for continuous casting, comprising a support frame having stop surface means, a mold formed by longitudinal walls and transverse walls for limiting a mold compartment thereof, said mold being provided with cooling devices, said longitudinal walls and transverse walls being supported by the support frame, support plates upon which the longitudinal walls are slidingly arranged at the side facing away from the mold compartment for expansion and contraction, adjustment devices provided for the transverse walls, said adjustment devices being supported by the support frame, said adjustment devices being connected with the associated transverse wall and with the support frame, exchangeable stop gauges provided between the transverse walls and the stop surface means at the support frame, said exchangeable stop gauges corresponding to a desired mold dimension during casting operation, said transverse walls being fixedly clampable between the longitudinal walls, coupling means operatively associated with each adjustment device for interrupting the connection between the associated transverse wall and the support frame, said coupling means during the casting operation permitting movement of the associated fixedly clamped transverse wall with respect to the stop surface means in the direction of the mold compartment and back again.

4. The Mold as defined in claim 2, wherein the support frame has a supporting surface, the adjustment device being a spindle adjustment device incorporating a spindle, a disk threadably connected with the spindle, said disk being slidingly supported at the support frame in the axial direction with respect to the spindle, a pre-biased package of springs arranged between the supporting surface of the support frame and said disk such that the spring force presses the associated transverse wall towards the stop gauges.

5. The mold as defined in claim 2, wherein the adjustment device is a spindle adjustment device having a spindle, said coupling means comprising a coupling element cooperating with the spindle for selectively disconnecting and connecting the spindle with the associated transverse wall.