WO2011039038A1

WO2011039038A1 - Support arrangement of a continuous casting system

Info

Publication number: WO2011039038A1
Application number: PCT/EP2010/063216
Authority: WO
Inventors: Kurt Fellinger; Günter LEITNER; Paul Pennerstorfer
Original assignee: Siemens Vai Metals Technologies Gmbh
Priority date: 2009-09-29
Filing date: 2010-09-09
Publication date: 2011-04-07
Also published as: DE212010000157U1; AT508791A1

Abstract

The invention relates to a support arrangement of a continuous casting system for producing strands having a rectangular format, comprising a side support roller unit (2) disposed below a casting die (1) for supporting a strand exiting the casting die (1), wherein the support roller unit (2) comprises at least two support rollers (4) fastened one above the other to a common beam (3), and wherein a mounting element (5) is coupled to the casting die (1), an upper area of the beam (3) being joined to said mounting element with a hinge by means of a horizontal guide (6) and said mounting element being joined to a lower area of the beam (5) via a hinge (7) by means of a guide element (8) aligned at a downward slant. The support roller unit (2) is thus protected against overloading.

Description

Support arrangement of a continuous casting plant

The invention relates to a support arrangement of a

Continuous casting plant for the production of strands of rectangular format, a arranged below a mold lateral support roller unit for supporting one of the mold

comprising outgoing strand, wherein the support roller unit has at least two superposed on a common carrier support rollers.

The production of metals by continuous casting plants accounts for a large proportion of the production volume of steel (among other metals), which is produced worldwide every year. Continuous casting plants typically have a mold with two substantially parallel

opposite broad and two in essence

parallel opposite narrow walls, the wide with the narrow side walls together in the

Cross-section rectangular molding channel. At the upper end of the casting channel molten metal is poured steadily while the cast strand emerges at the bottom of the casting channel. The strand is secondary in the course of the mold

Coolant jets further solidified until it is completely solid at or near the end of the continuous casting.

The emerging from the casting channel strand initially has only a thin solidified shell, called shell box on. Inside there is still melt. During the secondary cooling, after leaving the mold, the strand is guided by means of a plurality of support rollers.

Immediately below the mold are usually

Support roller units with one to five support rollers arranged on a common carrier. These support roller units generally form an assembly together with the mold. From EP 0 102 345 AI knows a lateral support roller unit, which is mounted below the mold and adjusting devices for moving the

Support roller unit has approximately perpendicular to the axis of the mold. Here is one supporting the supporting roles

Support plate hinged to another plate and is pressed by means of spring-loaded piston in the direction of the axis of the mold. These floating

Support roller unit needs a lot of space below the mold. In addition, the further plate with a connecting plate attached to the mold forms a console, which must be designed due to the leverage for transmitting large moments. In particular, at a casting start, a pouring end, a

Distribution change or operation with so-called creep speed, the situation arises that the formed in the mold shell box has a greater thickness than at

Normal operation has. Since the casting channel of the mold usually conically narrows, it forms a

Strand section, which emerges as a frozen cone from the mold. This frozen cone is usually stronger, the wider the casting format and the

Shell box is the stiffer, the lower the

Casting speed is.

A frozen cone can lead to the problem that the directly behind the mold downstream support roller units are overloaded. When passing the support rollers of the frozen cone exerts an increasing force on the support rollers, which are designed in itself only to support the strand. As a result, there is a greatly increased wear, which leads to shorter tool life and thus to a higher Kokillenwechselhäufigkeit and increased

Maintenance costs or replacement parts costs leads. The invention has for its object to provide an improvement over the prior art for a support assembly of the type mentioned. According to the invention, this object is achieved by the features of claim 1. In this case, a holder coupled to the mold is provided, to which an upper region of the carrier is pivotally connected via a horizontal guide and articulated to which via a joint by means of an obliquely downwardly directed guide element a lower portion of the carrier is connected. Such a design has the advantage that the carrier with the support rollers against the

Holder is movable, in the horizontal direction normal to the strand surface. The upper purely horizontal

Guide ensures that the support rollers in vertical

Direction in their location are determined. The oblique orientation of the connected to the lower area of the carrier

Guide element causes a compact design. Of the

Connection to the holder is shifted upwards relative to the connection to the carrier, so that the holder does not have to be guided downwards over the length of the carrier like a console. This is particularly advantageous for longer lateral strand guides. Due to the oblique orientation of the guide element, this takes up a large part of the forces acting on the support arrangement from the strand. The upper horizontal guide is therefore lighter

executable.

It is advantageous if the horizontal guide is arranged at a height with the uppermost support roller. The from a cone-shaped strand section on the top

Support roller acting horizontal force thus causes no effect on the horizontal guide tilting moment. Too high a transverse load on the horizontal guide becomes so

locked out. An advantageous embodiment of the invention provides that the horizontal guide comprises a horizontally oriented first cylinder, which covers the upper region of the

Carrier supported against the bracket. In addition to a guiding function, the cylinder also performs the function of setting the carrier with the support rollers against the strand.

A favorable structure of the first cylinder is given when a cylinder housing of the first cylinder is clamped in the holder and when a piston of the first cylinder is pivotally connected to the upper portion of the carrier.

For overload protected support of the carrier against the holder is in a simple expression of the first

Cylinder as a spring-loaded cylinder with a on the

Cylinder piston acting spring force formed. in the

Overload causes the force acting on the support rollers by the strand retraction of the upper support portion against the spring force.

A further development of this characteristic provides that the first cylinder as a spring-loaded hydraulic cylinder

is formed, in which a hydraulically generated counterforce can be applied to a force acting on the cylinder piston spring force. In this way, the upper support area can also be reset hydraulically.

Convenient for a compact design, it is when the force acting on the cylinder piston spring force is applied by means of disc springs.

In another form, the first cylinder is as

Hydraulic cylinder is formed, in which on the

Cylinder piston system hydraulic pressure acts. A

Continuous casting plant usually has an extensive hydraulic system, which can be used for this function. For the storage of the lower support area it is from

Advantage, if the obliquely downward

Guide element as a spring-loaded second cylinder

is formed, which supports the lower portion of the carrier against the holder. In case of overload, the force acting on the support rollers from the strand causes a retraction of the lower support portion against the spring force of the second cylinder. The second cylinder is conveniently as

spring-loaded hydraulic cylinder is formed, in which a hydraulically generated counterforce can be applied to a force acting on the cylinder piston spring force. The lower portion of the carrier is then hydraulically recoverable.

A favorable arrangement provides that the second cylinder is connected to the carrier by means of a first joint arranged at the level of the lowermost support roller and is connected to the holder by means of a second articulation disposed above it.

The invention will now be described by way of example with reference to the accompanying drawings. In a schematic representation:

Fig. 1 support arrangement, wherein the first cylinder is designed as a pure hydraulic cylinder

Fig. 2 support arrangement, wherein the first cylinder

spring loaded

The support roller unit 2 shown in Fig. 1 is fixed in a known manner to the underside of a mold 1. In this case, fastening means are guided by leading upwards cavities of the mold 1 and bolted to the top of the mold. This has the advantage that, for example, after a strand breakthrough one welded to the strand Support roller unit solved in a simple manner from above and the mold 1 can be removed.

The fastening means fix a holder 5 on the

Mold 1. At this holder 5 are over an upper

horizontal guide 6 articulated an upper area of a

Carrier 3 connected. In addition, on the holder 5 by means of a joint 7, a guide element 8 is pivotally connected to a lower portion of the carrier 3. At a side emerging from the mold 1 strand strand side of the support 3 a plurality of parallel to the strand arranged support rollers 4 are arranged. As a rule, two to five superposed rollers 4 are provided per support roller unit. At the height of the uppermost roller 4, a joint is mounted on the carrier 3, which allows a torque-free transmission of force to the horizontal guide 6, with which the carrier 3 is connected to the holder 5. The same function is provided when the hinge is attached to the holder 5 and the horizontal guide 6 is clamped on the carrier 3. The horizontal guide 6 comprises in a simple

Embodiment a hydraulic first cylinder. This is acted upon in the manner with a system pressure that the upper portion of the carrier 3 is made against a leaking from the mold 1 strand. In order to avoid overloading the upper support rollers 4, for example, a pressure relief valve is provided which limits the pressure prevailing in the hydraulic cylinder pressure. Reach those of one

forces acting on the support rollers 4 a permissible upper limit, opens the pressure relief valve and the carrier 3 moves horizontally relative to the holder 5. The carrier 3 is thus returned from the strand. The system pressure acting in the hydraulic cylinder can also be selectively reduced by means of a hydraulic control.

Optionally, the first cylinder is double-acting

Hydraulic cylinder executed. This is the top of the Support 5 retractable by means of a back pressure on the system pressure-loaded piston from the strand. With a

variable back pressure can also vary at constant system pressure, the contact force with which the upper portion of the carrier 2 is pressed against the strand.

The lower region of the carrier 3 is by means of a

Guide element 8 connected to the holder 5. This guide element 8 is designed in a simple manner as obliquely upwardly oriented second cylinder. On the holder 3 is viewed from the strand behind the upper horizontal guide 6 approximately at the same height a joint 7 to which one end of the second cylinder is connected.

Below the articulated connection of the upper horizontal guide 6, approximately at the level of the lowermost roller 4, located on the carrier 3, another joint 9, to which the second end of the second cylinder is connected. Conveniently, the cylinder housing is pivotally connected to the bracket 5 and the cylinder piston hingedly connected to the carrier 3.

The oblique installation position of the guide element 8 causes a compact design of the support roller unit 2, since a pulled down console bracket 5 is omitted. Especially at high casting speeds and large casting thicknesses, this is advantageous because this is a longer

Support roller unit 2 with more support rollers 4 is used. A console of the holder 5 would be a

Form the interference contour to the bending zone of the strand. In addition, a longer console would not be sufficiently stable.

A simple design provides that the second cylinder is spring loaded so that the lower portion of the

Support roller unit 2 is made by spring force.

Alternatively, this cylinder with a

System pressure to be applied. A piston rod of the second cylinder is conveniently designed to be adjustable in the axial direction, so that by a

Shortening or extension of the piston rod, the inclination of the carrier 3 with respect to the holder 5 is adjustable. The adjustability is for example by means of a

Fastening realized, the screwing is protected by a flexible protective cover against contamination.

Optionally, the second cylinder is designed as a double-acting cylinder. A counterpressure acting on the piston serves, on the one hand, to vary the setting force and, if the system pressure or a corresponding spring pressure is exceeded, to retract the lower carrier region.

An inventive storage of the carrier 5 with respect to the holder 3 thus allows a simple way to withdraw the carrier 5 in the horizontal direction from the strand. This is done either by means of a hydraulic pressure or by a conical portion of the strand.

2, a similar support arrangement is shown. On support 3, four rollers 4 are arranged unchanged. The essential difference from that shown in Fig. 1

Arrangement consists in a horizontal guide 6, which comprises a spring-loaded first cylinder. in the

Cylinder housings are provided a plurality of disc springs, which act on the piston of the first cylinder. The cylinder housing has a greater installation depth compared to a pure hydraulic cylinder. In the holder 5, therefore, the joint 7 for connecting the second cylinder is slightly offset down, without losing the advantageous oblique

Negative influence on mounting position.

The spring-loaded first cylinder is optional as

double-acting cylinder formed. By applying a Hydraulic counter-pressure, the spring force is varied or the upper support area withdrawn, that is lifted from a emerging from the mold 1 strand.

As a rule, a support arrangement located in an existing installation can be easily converted into an arrangement according to the invention. This is especially true for

Strand guides of open design, in which no outer shields are present. In molds with a closed design, so with shields, the retrofitting is given after an adaptation of the existing bracket.

The additional function of hydraulic retraction is after replacement of one usually on the mold

existing hydraulic block possible at any time. The function is integrated in the automation of the system in a simple way.

Claims

claims

1. support assembly of a continuous casting plant for producing strands of rectangular format, one below a

Molded support roller unit (2) for supporting a strand emerging from the mold (1), wherein the support roller unit (2) at least two fixed to one another on a common carrier (3)

Support rollers (4), characterized in that a to the mold (1) coupled to the holder (5) is provided, to which via a horizontal guide (6) hingedly an upper portion of the support (3) is shot and to which via a Joint (7) by means of an obliquely downward

directed guide member (8) articulated a lower portion of the carrier (5) is connected.

2. Support arrangement according to claim 1, characterized

characterized in that the horizontal guide (6) is arranged at a height with the uppermost support roller (4).

3. Support arrangement according to claim 1 or 2, characterized

characterized in that the horizontal guide (6) comprises a horizontally oriented first cylinder, which supports the upper region of the carrier (3) against the holder (5).

4. Support arrangement according to claim 3, characterized

characterized in that a cylinder housing of the first

Cylinder in the holder (5) is clamped and that a piston of the first cylinder is pivotally connected to the upper portion of the carrier (3).

5. Support arrangement according to claim 3 or 4, characterized

characterized in that the first cylinder as

spring-loaded cylinder is formed with a force acting on the cylinder piston spring force.

6. Support arrangement according to claim 3 or 4, characterized gekennzeichne that the first cylinder as

spring-loaded hydraulic cylinder is formed, in which a hydraulically generated counterforce can be applied to a force acting on the cylinder piston spring force.

7. Support arrangement according to claim 5 or 6, characterized

Mark that the spring force acting on the cylinder piston of the first cylinder by means of disc springs

is applied.

8. Support arrangement according to claim 3 or 4, characterized

characterized in that the first cylinder as

Hydraulic cylinder is formed, in which on the

Cylinder piston system hydraulic pressure acts.

9. Support arrangement according to one of claims 1 to 8, characterized in that the obliquely downwardly directed guide element (8) is designed as a spring-loaded second cylinder, which supports the lower portion of the carrier (3) against the holder (5).

10. Support arrangement according to claim 9, characterized

characterized in that the second cylinder as

11. Support arrangement according to claim 9 or 10, characterized in that the second cylinder is connected by means of a height of the lowermost support roller (4) arranged joint (9) to the carrier (5) and by means of a diagonally disposed above hinge (7) the holder (5) is connected.