NO780506L - PROCEDURE FOR COOLING AND CARRYING A CIRCULATING COOKING TAPE ON A CONTINUOUS CONTINUOUS STRAPPING DEVICE - Google Patents

Description

Method of cooling and feeding a revolving mold belt on a device for continuous strand casting.

The surrounding mold belt on a continuous casting device is not only cooled by means of a cooling liquid, but at the same time also quickly and held stably at a small distance from a lining plate by means of the hydrostatic forces exerted by this liquid. For this purpose, the liquid is fed into a number of small pockets in the lining plate's surface, in which hydrostatic pressure builds up depending on the distance between the mold band and pocket edge. On the outside of the pockets, there is an understress on the mold tape. In addition, this can be pulled against the lining plate by means of magnetic forces.

The hydrostatically strengthened mold belt can be set into mechanical oscillations perpendicular to its own plane by means of pulsating fluid supply or electromagnetically, if desired, at least in some places, to reduce the heat transfer from stop material to the mold belt.

There are various stopping devices that serve to continuously stop strips - hereinafter called "string" - of light or heavy metals.

In one type of these known stop devices, the stop mechanism is formed by two flexible, endless and circling metal bands, hereinafter called "mold band", between which the continuous

molten metal solidifies, and which is cooled using

of a dressing liquid on the stop chamber or stop-

the opposite side of the page, hereafter called "the back", to conduct away the heat from the solidifying stoping material. With stop devices of this kind, strings can i

all desirable widths and usually with a thickness from 10 to 100 mm are stopped continuously.

Here, the dressing liquid is fed using special nozzles and guiding devices at high speed on the back of the mold belts. A stop device of this type is described, e.g. in the U.S. Patent No. 2,904,860.

The stopping chamber is limited in the longitudinal direction on both sides by means of side shields which are placed between the mold bands oj whose height corresponds to the distance between the mold bands, and which thus determines the thickness of the string material. Preferably, a running side shield is used, which is placed over one of the mold bands and placed in circulation with this by adhesion. The shields consist of small blocks of metal or ceramic, which form an endless, closed belt, whose unwound length is somewhat greater than that of the mold belt. A side liner in the stope chamber area ensures the desired spacing of the two shields. The width of the string is given through this distance. Strands of different widths are produced by presetting these side liners.

Depending on the material and thickness of the stopped string, you can work with stopping speeds from 1

to 10 m/min.

The thickness of the mold band in the known devices is 0.5 to 2 mm. Depending on the temperature of the stoping material and the desired dressing effect, the mold belts can be provided with a heat-dissipating coating on

the side that is in contact with the stop material, thereby preventing a thermal overload of the mold belt or to prevent too rapid cooling of the strand.

Each of the mold bands is fed over one or more guide rollers, one of which is mounted in front and one behind the stop chamber and at least one of the rollers is driven, to set the mold bands in orbit corresponding to the stop speed. One of the rollers can be adjusted by means of known devices and allows the mold belt to be tensioned or untensioned for exchange. Furthermore, one of the rollers serves for the lateral lining of the mold band joint is equipped with a suitable control of a known kind.

The mold bands are supported in the stope chamber area

on the back of a number of narrow, rotating disks which are profiled in such a way that they offer the least possible resistance to the dressing liquid flowing over the mold bands. The discs have the task of absorbing the weight of the stoping material and any metallostatic pressure, and also the necessary forces to prevent wave-shaped failure of the mold bands.

The stopping device is mounted on a specially constructed stand, which allows the necessary adjustment of the thickness and width of the string to be stopped. On one side, the shape of the stand allows free access to the stop device, so that the mold bands can be replaced quickly and without special precautions.

On the outlet side of the stopping device, driven rollers are arranged, which in operation grasp the stopped string and feed it for the following operations

in accordance with the stopping speed.

A dressing plant with the necessary components, such as dressing agent tank, piping system, pumps, heat exchanger, filter, regulation and safety equipment is necessary so that the dressing liquid can meet the chemical and physical operating conditions and circulate through the stop device in the required quantity to dress the mold bands . Depending on the local conditions, open or closed circuit runs can be used. Water or a water-oil emulsion is usually used as the dressing liquid.

Experience shows that it is associated with major problems to prevent failures of the mold band and thus an even cooling of the stope.

As a mold band can indeed be tensioned in the circumferential direction, but not transversely, this always shows a tendency in the stop chamber area to warp in a wave shape due to thermal stresses. The consequence is that the mold strip rises from the stope in some places and thus causes a non-uniform cooling of the sides and surface of the string. In terms of experience, this results in quality defects in the strand, which, depending on the alloy and type of stope, appear in the form of surface shrinkage, porosity, coarseness, cracks and thickness variations, etc.

The aforementioned defects can be avoided if the cooling of the stock is sufficiently uniform on both sides and over the entire width.

Experience shows that this condition can only be met if the wave variations or the unevenness of the mold band amounts to less than 0.05 mm in the course of the stop stretch.

Even when using material with an extremely low thermal expansion coefficient for the mold belt - e.g. high-alloyed material with Ni or other elements, known under the term INVAR - the problems cannot be resolved satisfactorily, as the mold belt with stop devices of a known type, next to the thermal ones, is also exposed to other stresses, which will be discussed later.

It is also known to use rigid, belt-shaped mold blocks that are hinged to each other instead of the flexible mold bands. These move in a closed lining system together with the stop goods in the longitudinal direction of the stop stretch, which is achieved with the help of a suitable device. The cooling takes place in a room that is under atmospheric pressure, as the mold is flushed with a cooling liquid. The dressing liquid hits the mold through a large number of regularly distributed nozzles and liners, thereby removing the amount of heat that is taken up in contact with the stopping material. (Swiss Patent No. 456,056) .

The principle of flushing the mold liquid in a room under atmospheric pressure is now also used for stripping flexible mold bands (English patent no. 1 387 992). Instead of the aforementioned rotatable support discs, fixed support rods are also used which are mounted across the mold belts. Due to the negative pressure exerted by this method on the dress surfaces of the mold bands, these are sucked against the rejection. This precaution is intended to counteract the tendency of the mold bands to warp in the form of a wave and at the same time improve the skirting effect.

Experience shows that it is an advantage for the quality of the stope material if the direction of the stope slopes downwards.

In order to meet all the demands made by continuous string stuffing of the various relevant materials,

is it necessary that the stop device can be adapted to the individual conditions, i.e. that it must be able to function with any inclination of the stop chamber from horizontal to vertical direction.

Since plants with high performance require stope chambers

with lengths of up to 2 m and more, with a corresponding depth in the stope, with increasing slope a relatively high pressure occurs on the co^killer bands and their offsets due to the metallostatic pressure.

Under the assumption of a constant stope depth, this pressure is naturally proportional to the stope's specific weight.

When stopping heavy metals, such as e.g. copper,

zinc, tin, lead, steel, etc., it is therefore extremely problematic to stop with a steep downward slope, and above all when there is a negative pressure on the entire dress surfaces of the mold belts, as this leads to a significant increase in the previously high loads from the stop material.

The vertical stopping direction is particularly preferred from the stopping technical point of view, as this achieves the best mold filling, a high metallostatic pressure on the bottom of the stopping chamber and a symmetrical cooling in relation to the longitudinal axis. These are factors which, for known reasons, have a positive effect on the quality of the stop goods.

When -using rotating support discs, up-

stands between these and the mold band very hfiye speci-

received pressure due to the necessarily extremely small contact surfaces. Even after a short period of operation, this can lead to damage to the back of the mold belt, where

at its service life is significantly reduced.

Stationary belt lining elements cause

on the other hand, even if they are equipped with a sliding coating, considerable friction with corresponding wear on support elements and mold bands, which likewise leads to increased operating costs.

At relatively low gl/de speeds also occur

danger of "stick-slip" - effect on the sliding surfaces of the support elements, which can lead to surface scratches and other defects in the stop goods.

All known belt liners are also affected

with the disadvantage that the mold band can bend backwards over the permitted limit between the support elements under the influence of the weight and/or the metallostatic pressure in the stoping material and/or possibly prevailing negative pressure in the dressing space associated with possible other influences.

The purpose of the present invention is a method which allows a mold belt to be dressed and lined in the longitudinal direction of the stop section so that faults are excluded, whereby a uniform cooling over the entire width of the string is achieved and the above-described disadvantages of the known methods and devices are eliminated. Furthermore, a device for carrying out the method is also described, with which metal strings can be stopped in any practically desirable width between two flexible, wraparound, endless die bands.

The invention relates to a method for dressing and lining a revolving mold band and a device for continuous casting of metal strands, whereby dressing liquid is supplied under pressure from several inlet openings to the back of the mold band, which faces away from the dressing chamber, and is diverted at lower pressure, characterized in that the dressing liquid is introduced on the back of the die band into a number of separate pockets with edges facing the die band, so that it completely fills the pockets and the space between these and the die band and emerges from any pocket between its edge and that of the die band, after which it is diverted under lower pressure. The drainage cross-section from each pocket is determined by the distance between the mold belt and the pocket edge, so that depending on this distance, a hydrostatic pressure field is formed that acts on the mold belt in each of the pockets, which together with the lower pressure that prevails outside the pockets keeps the running mold

tcU£,

the strip independently at a practically constant distance from the edge of the pockets, whereby the mold strip is kept warp-free in the stope chamber area and at the same time lined hydrostatically.

From the hitherto known methods for dressing and lining (supporting) a mold band in the area around the stop chamber, the method according to the present invention differs in principle in that the mold band in the stop chamber area is not supported and lined by mechanical elements, such as rotating support discs or fixed substrates, but that, with the help of the mold fluid, hydrostatic forces are produced which prevent the mold boat from warping and hold and guide it in the desired position. The dressing bag is preferably fed under turbulence into the pockets, so that the dressing of the die strip is intensified.

To carry out the method according to the invention, an inventive device can be used, which exhibits a lining plate mounted in the stop chamber area behind the mold belt, with inlet openings connected to a coolant pressure chamber and drain openings connected to a negative pressure arm, characterized by the fact that the lining plate on the front, which faces the mold belt, is divided in a number of separate ):jole chambers, each of which has a pocket with an edge facing the mold band, and that at least one of the inlet openings opens into each of the pockets, while the outlet openings and the front of the lining plate open outside the pockets,

so that the outlet cross-section from each pocket is determined by the distance between the mold belt and the edge of the pocket, so that the mold fluid added under pressure fills the pockets and builds up a hydrostatically acting pressure field against the mold belt in each pocket, the size of which depends on said distance and thus,

together with the lower pressure that prevails outside the pockets, the die band independently maintains a practically constant distance from the edge of each pocket.

The following description of preferred embodiments of the invention relates to a single mold belt. In the case of stop devices with several mold belts, the invention can of course be used for all belts.

The lining plate, located a short distance behind the mold band, whose length and width are somewhat larger than the corresponding dimensions for the stop space, preferably has a thickness of the order of 20 to 50 mm, and can be composed of several parts, if this is advantageous for the production or 'other reasons. It is also possible to arrange the lining plate only over a part of the stop chamber or dress and line the mold belt over the other part of the stop chamber in another way. The lining plate now has inlet and outlet openings at a relatively small distance from each other, distributed over the surfaces facing the mold band. J<*>The supply openings are connected to a chamber, here called "pressure chamber", into which the dressing liquid is supplied under pressure.

The drain openings, on the other hand, open into a chamber with lower pressure (usually ambient pressure) here called "low-pressure chamber". From the low-pressure chamber, the cooling liquid is continuously fed away.

Due to the large number of inlet and outlet openings preferably arranged at regular intervals, it is expedient to divide the lining plate's surface facing the mold band above the stop chamber area into congruent fields, so that each of these fields has at least one inlet and one outlet opening. In the case of a complete division of the surface, the dress chambers have, according to geometrical laws, the shape of a polygon, more precisely three, four or six sides. Regular three-, four- or hexagons can be used here, but it is also possible to use rectangular dress chambers, in the form of strips that extend over the entire width, part of the width or the longitudinal direction of the mold band.

As described in the following, these dress chambers are shaped so that the kioleva box that flows from the pressure chamber to the low pressure chamber flows on the back of the mold belt and dresses this intensely and completely over the entire dress core surface, and that a positive and a negative hydrostatic pressure field are formed in relation to to the ambient pressure in each dress chamber. From these pressure fields, a resulting force acts on the mold belt in a specific dependence on the distance between the lining plate and the mold belt, so that the mold belt automatically occupies a specific distance from the lining plate in the area of each shell chamber, and is thus lined and held stably over the entire stope chamber surface, so that a unwanted deformation of this surface is excluded.

In order for the dressing liquid that flows out of the inlet openings to spread uniformly and without great flow resistance between the lining plate and the mold band, a recess - here called a "pocket" - is placed in each dress chamber around the inlet opening or openings. The depth of the pockets can range from a few tenths of a millimeter to several millimeters. The edge of the pocket' is preferably made as large as possible, so that it is separated from a drain opening only by a narrow edge of less than 0.5 mm width.

As the pockets are constantly filled with cooling liquid during operation, a strong turbulence is caused in them by the flowing liquid, whereby an intense cooling of the mold strip in the area of each pocket is achieved.

Above the edge of the pocket, a sufficient dressing effect is likewise achieved, as the flowing away dressing liquid flows at a relatively high speed between the narrow edge and the mold band into the drain opening.

The dressing conditions above the drain openings are discussed later.

Each access opening in the pockets in the dress chambers. is preferably connected with an individual rudder to the pressure chamber. As the dressing liquid preferably flows at a high speed on the mold belt to achieve a good dressing effect, it is appropriate to have a nozzle-shaped narrowing of the inlet openings in the pockets of the dressing chambers.

The drainage openings from the dress chambers on the upper side of the lining plate are preferably designed as slits,

which surrounds the pockets. Thereby, the dressing liquid between the lining plate and the mold band in each dressing chamber flows from the additional opening, which is advantageously placed in the center of the dressing chamber, in all directions to this gap,

which surrounds the pocket and at the same time forms the border of the dress chamber.

Apart from the edge of the lining plate, the garment liquid thereby always flows from two adjacent pockets to the common intermediate slot.

The slits have a depth of preferably 8

to 12 mm and, as previously noted, is directly connected to the low-pressure chamber through holes in the lining plate.

For the reasons stated below, the distance between the lining plate and the mold band adjusts automatically in relation to the forces acting on the latter above each dress chamber, and the mold band stays in stable equilibrium at the level that is set.

Due to the flow resistance in the inlet tubes and the nozzle-shaped narrowing of the cross-section at the inlet to the pockets of the dress chambers, the hydrostatic pressure in each pocket according to the laws of the flow layer depends on the cross-sectional area of the outlet.

If the die strip rests on the lining plate,

then the outlet from the pocket is closed. In this case, no current flow and therefore no pressure drop can be maintained in the respective inlet valve. Thus, the hydrostatic pressure in the pocket is the same as in the pressure chamber. If the mold band is removed, the dressing liquid begins to flow, with a corresponding drop in pressure in the inlet tube. If the free cross-sectional area, i.e. the product of the pocket circumference and the distance between the mold band and the lining plate, becomes so large that it at least corresponds to the cross-sectional area of the drain opening in the low-pressure chamber, the pocket can be described as completely open. It then exhibits approximately the same pressure as when entering

flowed to the drain openings which are connected to the low pressure chamber. The pressure difference between the pressure chamber and the dress chamber's pocket is thereby formed as a result of the pressure drop in the nozzle and the flow resistance in the dress chamber's inlet valve. Thus, the hydrostatic pressure for a closed and a completely open pocket for an existing lining plate is in principle determined by a given pressure in the pressure and low pressure chambers. Consequently, any intermediate distance must be assigned a specific pressure in the pocket.

The dimensions of the dress chambers with and. drain openings and the pressures in the pressure and low-pressure chambers are now chosen so that the distance between the mold band and the lining plate, respectively the pocket edge, in operating conditions lies between the above-mentioned extremes. In this way, two pressure fields build up in each dress chamber, which act on the back of the mold band. One, produced by the flow pressure acting on the back of the die band and the hydrostatic pressure in the pocket, pushes the die band away from the lining plate and is termed positive. The other, which exhibits a negative pressure in relation to the ambient pressure, because it lies above the drain openings connected to the low pressure chamber, is designated as negative, as it exceeds a resultant force on the die band, which is directed towards the lining plate.

Even at the slightest reduction of the distance somewhere in the dress surface, be it due to increasing pressure forces in the stop chamber or as a result of local deformations of the mold band, the positive pressure field immediately builds up with the increase of the hydrostatic pressure in the pockets of the associated dress chambers, as the drainage from these pockets narrows as the mold belt gets closer.

In these dress chambers, an increased force thereby arises, which counteracts the mold band approaching the lining plate.

The reverse effect occurs when the die band separates from the lining plate. Due to the associated increase in the drain cross-section from the pockets of the dress chambers located at this location, the force from the pressure fields in these pockets decreases, whereby a yoked force directed against the lining plate results, which counteracts the mold band removing seq.

Due to the stabilizing effect of the principle described, each dress chamber thus causes a precise regulation in its area, i.e. a constant distance between the mold band and the lining plate. This distance adjusts itself automatically in relation to the prevailing pressures in the pressure and low-pressure chambers, the dimensions of the chamber, the dimensions of the inlet and outlet openings and the forces acting on the mold belt from the stope chamber.

The surface of the dress chambers can be divided into two zones, namely the one above the pocket, which has a stabilizing effect on the distance between the mold belt and the lining plate, and the one above the drain opening, where conditions are practically indifferent due to the negative pressure prevailing there, which is not especially depending on the position of the mold belt.

Due to the force fields acting on the mold band in the dress chamber areas, an unwanted bowing of the mold band can occur.

This problem can be solved without affecting the intense cooling of the mold belt if the dimensions of the clothing chambers, i.e. their length and/or width, are chosen sufficiently small. In the case of dress chambers in the form of regular triangles, quadrilaterals or hexagons, the dress chamber rafts should not make up more than 10 cm, preferably 1 to 6 cm, and the stabilizing zone should make up at least 50%, preferably over 70% of the dress chamber's total area. The cross-sectional area of the inlet opening or openings in a dress chamber must lie between 0.5 to 3.5% joint in each dress chamber, the area of the drain openings should preferably be two to ten times as large as the area of the inlet openings.

The pressures in the pressure and low-pressure chambers can be adapted to the conditions and preferably amount, depending on the specific weight and temperature of the stope material and the slope of the stope chamber, to between 2 and 5 bar abs. in the pressure chamber and from 0.5 to 0.9 bar abs. in the low pressure chamber. The above values are used at high stope temperature and/or high specific weight of the stope material and/or with a strong slope of the stope chamber.

Under the described conditions, a distance of 0.02 to 1 mm will set up during operation between the lining plate and the mold belt. Over the entire dress chamber area, the distance of the mold belt from the lining plate is kept within such narrow limits that the local deflections due to mechanical and thermal stress are so small that the previously established condition for this relationship can be complied with without further ado and thus no harmful effects on the quality of the string can occur.

The specified distance can be varied arbitrarily by

to change the drainage cross-section over the stop chamber's longitudinal direction.

The lower value is preferably used at the beginning of the stop chamber, i.e. on

the stretch where the stope material only has a blufft or sprue crust, while the higher value applies to the outlet side.

,Since the drain openings of the dress chambers can be designed as parallel slots that surround the pockets, and since the drain cross-section is only twice to ten times the cross-section of the inlet opening, the slots must be made relatively narrow due to the size of the dress chambers.

As the dressing fluid from two adjacent dressing chambers flows from the opposite direction and collides with each other over the slit opening, a strong turbulence in the dressing fluid also occurs at this location, which causes the necessary stripping of the mold band to be achieved outside the pockets, and thus completely over the entire dressing chamber surface, and in its trip also'stope chamber.

The low-pressure chamber is preferably arranged immediately behind the lining plate and the pressure chamber directly behind the low-pressure chamber, separated by a partition, and the chambers. extends eeg over the entire surface of the lining plate. Thus, it is possible to connect the dress chambers directly with the low-pressure chamber by means of through holes in the lining plate. This is a major advantage as the flow resistance for the return liquid is minimal in this way. This means that the negative pressure in the low-pressure chamber does not need to be significantly higher than that required in the drain openings of the dress chambers.

The inlet valves for the supply of dressing liquid

from the pressure chamber to the dressing chambers thus passes through the low-pressure chamber. In this, the flow of dressing fluid is therefore inhibited. In order to keep the pressure loss here within reasonable limits, it is necessary that the distance between the lining plate and the opposite wall in the low-pressure chamber is sufficiently large. Depending on the allowable<p>srore's diameter and mutual distance, the above-mentioned distance is preferably chosen with 5 to 25% of the square root of the lining plate's wear surface.

In the device described so far, as mentioned usually, depending on the conditions, a more or less high negative pressure must be maintained in the low pressure chamber in relation to the ambient pressure. However, if the negative pressure is too high, cavitation can easily occur in the liquid that is sucked away, especially because this liquid is heated. If the mold strip consists of ferromagnetic material, this can be prevented by applying a magnetic field to the back of the mold strip, which pulls the mold strip towards the lining plate. These magnetic fields then support the effect of the negative pressure, with which the dressing liquid is sucked away, so that this negative pressure Jean is smaller, without the effect being impaired. The magnetic fields are suitably produced using electromagnets, as these can be switched off if, for example, the mold belt must be replaced. The magnets, preferably electromagnets, can be suitably fixed in or on the lining plate.

The total amount of mold liquid that must flow through the mold chambers in order to produce the necessary hydrostatic pressure fields in them and to hold and guide the mold belt at the desired distance from the lining plate is relatively large. In order for this entire amount of dressing fluid to flow from the pressure chamber through the dressing chambers to the low-pressure chamber, it is necessary to have correspondingly large dimensions for pumps, lines, filters and other fittings in the cooling system, through which the dressing fluid flows from the low-pressure chamber and back to the pressure chamber. The amount of liquid flowing through the dress system can be reduced by arranging a jet pump in at least some of the connections between the inlet openings and the dress liquid pressure chamber, the suction side of which is connected to the drain openings to transfer dress liquid directly from the drain openings to the inlet opening. With this precaution, it is possible to reduce the amount of dressing liquid circulating in the dressing system to less than 50% of the amount flowing through the dressing chambers. More than 50% of the liquid quantity from the discharge openings can therefore be supplied to the inlet openings without detouring through the low-pressure chamber, cooling system and pressure chamber. This leads to significantly lower investment costs for the cooling system. Due to the relatively low temperature rise of the mold liquid in the mold chambers, the proposed solution with regard to the heat transport, i.e. the removal of heat from the back of the mold belt, is easily possible. For operation of the jet pump, it is usually sufficient to increase the pressure in the pressure chamber to approx. 4 to 12 bar abs. instead, as previously suggested, 2 to 5 bar abs., depending on the stop temperature and/or the specific weight of the stop material and/or the slope of the stop material, as the pump characteristics are adapted accordingly.

With the described method of dressing and lining a mold band in the stop chamber area, one does not need the high pretension of the mold band in the scope direction which is otherwise required to keep this as flat as possible over the stop stretch. Furthermore, only extremely small forces are required to keep the mold belt in circulation, as only liquid friction prevails between the mold belt and the lining plate. Both of these conditions allow the mold belt to be put into operation without significant pre-tensioning. A minimal bias is only conditioned by the drive mechanism. Thus, the die strip in the area of the stop stretch is practically only exposed to the thermal stresses, which results in a significantly longer service life. For the aforementioned reasons, the guide rollers can be dispensed with, which in other stop devices with mold bands are located in front of and behind the stop chamber. Instead of these, the mold belt can be guided over several lining rolls of relatively small diameter, which are arranged across the width of the mold belt and along an arc about the desired angle.

This construction method offers the essential advantage

that the nozzle which serves to supply the molten metal to the stopping chamber can be significantly shorter and thus more stable and simpler, and that the string that is stopped

in the stopping device, can be grasped and lined by them; so-called advance rollers in the shortest distance after the stop chamber. In addition to saving space, this also leads to increased operational reliability for the stop device.

As the friction between the string that is stopped and the mold band is, for previously mentioned reasons, greater than the friction between the mold band and the stationary part of the stop device (liquid friction in the stop chamber area), the mold band can be dragged along by the moving string at the same speed and thus put into circulation when the solidifying part of the string can absorb the necessary traction, which depends on the properties of the material being stopped. Under these circumstances, a special operating device and the associated speed controls for the mold bands can be dispensed with, whereby the stop device becomes significantly simpler.

Another advantage of the described hydrostatic lining of the mold belts is that, if desired,

it is possible to produce mechanical oscillations in the mold band perpendicular to it in the area where it is in contact with the stop material. With such fluctuations can

ill

the heating line from stope material to mold belt is reduced. This may possibly be desirable in order to prevent a thermal overload of the mold belt and/or to prevent too rapid cooling of the stop material.

In order to reduce the heat transfer from the stop material to a mold band, it is known per se to equip the side of the mold band that is in contact with the stop material with a heat-insulating layer. This solution is, however, 'bound with a number of problems. Firstly, it is relatively difficult to apply a coating that adheres well enough, secondly, it is very difficult to achieve a coating with sufficiently uniform thermal insulation over the entire surface of the mold strip, and thirdly, the coating is exposed to wear, which leads to the loose particles from the coating become suspended as foreign bodies on the surface of the string and can thus affect the quality of the finished product.

These disadvantages are avoided with the present invention through reduction of the heat transfer due to mechanical fluctuations. A further advantage consists in the fact that these oscillations can be produced by choice in only a part of the mold belt area that is in contact with the stop material, in order to reduce the heat transfer only in this part, especially in the inlet area of the stop stretch, where the thermal load, and thus the risk of failures of the mold band, is largest. Naturally, one can also induce oscillations whose amplitude slowly decreases along the longitudinal direction of the stop chamber.

In short, an arbitrary spatial or temporal control of the heat transition is possible at any time.

The oscillations can be made sinusoidal

or also in other forms. In order to achieve the desired effect optimally, it is appropriate if the frequency of the oscillations is between approx. 20 and 500 sec ^ and the swing--5 -4 ning amplitude between approx. 2-10 and 2-10 meters.

In the case of sinusoidal oscillation, the drop is in the heat transfer

2

particularly strong when the ratio h*f > 0.5 is fulfilled, where h is the amplitude in meters and f the frequency in sec ^. For other forms of oscillation, the product h-f 2 may be somewhat smaller.

If the mold band consists of ferromagnetic material, the oscillations can be induced, for example, by means of alternating magnetic fields.

But the oscillations of the mold band can also, regardless of its material, be induced by the pulsating supply of the dressing liquid to the back of the mold band,

at least in some places. If the inlet openings are connected by separate inlet pipes, a pulsating flow of the dressing liquid in the inlet pipes can be induced as the cross-sectional surface of the pipes is changed periodically. This can be achieved in the simplest way with the help of a swinging valve in the liquid supply line. Each inlet rudder can have its own valve with corresponding sizes. As valves, such can be used where the valve body is set in oscillations by the flowing cooling liquid, so that the flow cross-section changes periodically, but it is better with electric control.

On the basis of the drawing, the invention will be described in more detail in the following examples.

The drawing shows:

Fig. 1 a stop device with a vertically arranged stop chamber as well as lining and dressing the mold bands according to the invention. To the left on fig. 1 Fig. 2 shows the device with the gaze directed towards the mold band and makes visible a release for hanging the device and a foundation that rests on a stand with free access from the right to be able to exchange the mold bands. Fig. 3 to 11 illustrate on a larger scale sections and elevations for different design forms for the lining plate with coil chambers, for feed pipes, drain holes, low pressure chambers and mold belts. In all the cases produced, the lining plate consists of a base plate with attached skirt chamber elements. Here shows: fig. 3 and 4 in cross-section, the respective elevation arrangement for hexagonal dress chambers and likewise hexagonal pockets, without side seams between the mushroom-shaped dress chamber elements,

fig. 5 and 6 again in section and elevation, respectively, a structure of the lining plate with square skirting chambers and with round, mushroom-shaped skirting chamber elements and with a side flap in each corner of the kj51e chambers,

fig. 7 and 8 likewise in section and elevation, respectively, a structure of the lining plate with hexagonal dress chambers and with round, mushroom-shaped dress chamber elements and with a side tillop in each corner of the dress chambers,

fig. 9 in a similar section as fig. 3 a variant where the dress chamber elements are first equipped with jet pumps and then with magnetic windings,

fig. 10 in section a self-oscillating valve in the inlet pipe of a dress chamber element and

fig. 11 in a similar section as fig. 10 an electrically controlled valve.

In the stop device according to fig. 1 and 2, a high-pressure chamber 11 is arranged in a housing 10, shown in section

in fig. 1, which is fed with dressing liquid under pressure from

an opening 12. This flows into inlet rudder 14 through a low-pressure chamber 15 and through a lining plate 13,

which is arranged at a small distance behind a circling, endless mold belt 20 in the area of a stop chamber 26.

As can be seen from fig.l, the endless mold belt 20 runs over a driven roller 23, then reaches a guide part 24, which is equipped with arc-shaped pre-rolls 25, and then runs over the liner plate 13, which is arranged behind the stop chamber 26. outlet of the stop chamber, the mold belt 20 runs further over a lining roll 28, arranged on a lower guide part 27, to the driver roll 23. The lining rolls 25 and 28 preferably have a diameter of 20 to 25 mm. It is advantageous to arrange several narrow rolls with intermediate support bearings across the width of the mold belt 20. The axes of rotation of the rolls can also be shifted relative to each other, so that a stepwise arrangement of the rolls is achieved. Through a tight, step-by-step arrangement of the rolls, it is possible to achieve a lining and support for the mold belt that meets all requirements.

The driver roller 23 is suspended in the fasteners 29 by means of tension cylinders 30 on both sides and can be displaced in the horizontal plane, so that the mold band can easily be tensioned pneumatically or hydraulically or, if necessary, completely relaxed in order to be exchanged.

By means of a cylinder 31 at the rear part of the roller 23, this can be swung in the vertical plane,

so that a lateral discharge of the mold belt can be prevented by means of a control of a known kind.

The stopping chamber 26 with the drawn string 32 is delimited on both sides by the so-called side shields. These consist of an endless chain of blocks 33 of metal or ceramic material, interconnected by joints or flexibly, and resting on one of the mold bands, so that they move with this in the rotational direction.

With the help of non-engaged, adjustable side liners, the distance between the side shields and thus the width of the string to be stopped can be adjusted as desired.

The molten metal is led from the furnace through a container 34 and then to a stop nozzle 36 through a number of rudders 35 of ceramic material, arranged vertically next to each other in the stop plane. The amount of molten metal flowing through is controlled by level controls of a known nature.

From the stop nozzle 36, the metal flows evenly distributed over the width of the string to be stopped, into the stop chamber 26, where the volume released as the string moves continuously downwards is constantly replenished with molten metal.

On the cooled mold strips, a crust 37 first solidifies, the thickness of which increases with increasing cooling, so that a core of liquid metal is maintained until the strand's cross-section is completely solidified. Because the string leaves the dress chamber, a further undressing of approx. 20% of the solidification temperature, whereby the material achieves the necessary firmness for further processing.

Under the stop device, the string is caught between two advancing rollers 39, which are driven synchronously with the stop speed and ensure a uniform lowering of the string.

The two halves of the stop device, located on both sides of the string, are each fixed on a movable base 42, equipped with rollers 41 that run on rails 40. By means of cylinders 4 3, both units can be driven a few decimeters apart , which is necessary to be able to change the mold bands. An unmarked, adjustable stop ensures the correct spacing of both units when they are driven together in operating position.

Fig. 2 illustrates a possible solution for setting up the stop device on a stand 44, where access from the right is provided for exchanging the mold bands. The stand is anchored with powerful screws 4 5 to a foundation 46. While the rollers 41 carry the weight of the device, the rollers 47 and 48 take over the horizontal forces arising due to the one-sided suspension of the device. Thus, the corresponding torque is compensated.

The operation of the roller 23 takes place over joint shafts 49 and the operation of the drive roller 39 over joint shafts 50 by means of a non-registered drive.

The dressing liquid circulates from and to the dressing water system through two rudder spigots 51 and 52, as the dressing liquid flows into the device through the rudder spigot 51, which is attached to the connection 12 and leaves the device through the rudder spigot 52, which is located on the connection 22. Both rudder spigots are connected by k the coolant heater using flexible lines. For the sake of simplicity, both of these elements are not drawn. In the event that the material to be stopped does not require any special operation of the mold belt, the articulated shafts 49

and thus the corresponding drives and operational components redundant.

In the following, embodiment examples are now described for the lining plate 13, with the help of which the mold band 20 is hydrostatically supported by the dressing liquid.

The lining plate 13 is in fig. 3 and 4 built up from a base surface 16 and separate small blocks 60, hereinafter called "dress chamber elements" or "elements", which serve to form dress chambers and are attached to the base surface. The dress chamber elements 60 each have a pocket 56, as already described, each with its own inlet opening 57, connected to an inlet valve 14. The joining can take place using known methods, such as e.g. with screws or glue.

The surface of the lining plate is now understood to mean the surface that lies above the dress chamber elements 60.

Once determined, the size and shape of the dress chambers, respective spacing of the dress chamber elements 60

on the base plate 16, the dress chamber elements are made so large that gaps 58 occur between them, which serve as drain openings. The height of the elements 60 is here preferably 8 to 20 mm, and the width of the slits 58 on the surface of the lining plate 13 is dimensioned in accordance with the previous indications so that the overall cross-section that accrues to a dress chamber is twice to ten times the cross- the cross-sectional area of the access openings 57.

For the drainage of the dressing liquid, the base plate 16 is equipped with the necessary holes 21, which correspond to the slots.

In the pockets 56, the mold liquid, which flows through the nozzle-shaped opening 57 in the inlet tube 14, spreads beyond the mold band 20 and then flows into the slits 58 and from there through the outlet openings 21 into the low-pressure chamber 15 and further (fig. 1) through the outlet 2 2 to a not registered k jole water tank.

Even if the dress chambers have the shape of a triangle, square or hexagon, you can also use round dress chamber elements, which are easier to produce.

Round dress chamber elements 60' with pockets 56' are produced in different arrangements in fig. 5 and 6, respectively in fig. 7 and 8, namely in square dress chambers in fig. 5 and 6 and in hexagonal in fig. 7 and 8.

As a result of the geometrical conditions, however, there would be insufficiently stripped areas on the mold band 20 in the corner of the dress chambers due to a lack of circulation of the dress liquid outside the pockets 56. In order to still achieve a sufficient and complete stripping of the mold band 20 over the entire surface to the stope chamber 26, a further inlet opening 61 - hereinafter called "side inlet" - is placed in each corner of the dress chamber. Through this, the mold liquid flows from the pressure chamber 11 at a sufficiently high speed onto the mold belt 20. With this precaution, a strong turbulence develops in the liquid which is located between the elements 60<*> in the chamber 58' and 58", respectively, so that also outside the mold chamber elements 60' achieves an intense cooling of the mold belt 20. It is likewise advantageous to connect each side inlet 61 with a separate inlet line to the pressure chamber 11.

In the present case, mushroom-shaped dress chamber elements 60' are used, which are attached to the base plate 16 in such a way that the hat of the mushroom is directed towards the mold band 20. The cross-sectional area of the stem preferably comprises approx. 40% of the dress chamber surface. The hat's minimal surface should preferably make up at least 50% of the dress chamber's total surface, in order to fulfill the previously mentioned condition with regard to the size of the dress chamber's stabilizing zone.

However, the largest diameter should not amount to more

than 98% of the distance between the midpoints of two adjacent elements, so that the liquid can flow unhindered out of the pocket.56<*>.

The mushroom-shaped shape of the element 60' ensures that there is sufficient space on the base plate 16 for arranging the side supply openings and the drain openings 21.

In contrast to the dress chambers with polygonal dress chamber elements, the aforementioned condition for the cross-section of the drain openings with round elements 60' does not relate to the surface 58', which lies between the elements 60', but instead to the drain openings 21 in the base plate 16.

Under certain conditions, a mold belt can

have a tendency to be set in oscillations of the liquid liquid stream, which can have unfavorable fSlgcr. It is, however, possible to prevent these oscillations, as the length of the side-mounted inlet rudder 14 is varied by a few centimetres. This is achieved, as the individual rudders 14 project more or less far into the pressure chamber 11. Thus, the natural frequency of the oscillations in the cooling liquid in the rudders 14 can be varied sufficiently to prevent mutual resonance frequencies, and thus prevent an unwanted vibration of the mold band 20.

To prevent the mold band from bending

between the support elements under load, mold tape with a thickness of 0.5 to 2 mm must be used, usually 1 to 1.5 mm for stop devices of known construction, as the distance between the individual support elements as a consequence of the construction is relatively large.

The dressing procedure described here

and lining of mold tape, on the other hand, allows to use mold tape with a thickness of 0.1 to 0.4 mm.

This is made possible by the large number of relatively small dress chambers as well as the high proportion of stabilizing and supporting zones in the dress chambers' surface. A significant advantage of thin mold belts compared to thick ones is that the forces that arise in the mold belts due to the thermal stresses are significantly smaller, according to the basic principles of the strength layer, which means that the forces that must be applied to the mold belt to prevent failures are correspondingly smaller .

The following part of the description relates in particular to stop devices^<V>slope chamber is formed by two opposite mold bands 20 and between these arranged side shields, as shown in fig. 1 and 2.

In the event of a strong slope, or as in fig. 1 and 2, vertical stop direction, it is advantageous that the ratio between the cross-sectional rafts of the drain openings 58 resp. 21 to cross-section the rafts of the inlet openings 57 in the lining plate 13 gradually narrow towards the outlet of the stop chamber 26. Due to the relatively smaller outlet cross-section, it is thereby achieved that a pressure builds up in the dressing liquid, which increases downwards in the adjacent dressing chambers between the lining plate 13 and the mold belt 20. In this way, the metallostatic pressure in the stopping chamber is counteracted and at the same time shrinkage gaps between the two mold bands 20, which form the stopping chamber 26, and the solidifying stoping material 32 are prevented.

The same effect can also be achieved with successively larger inlet openings 57, this discharge, however, requires a larger amount of dressing liquid.

After the stoping material 32 has solidified completely, the cross-section of the drain openings 58 or 21 is reduced to a ratio of 2:1 in relation to the cross-section of the inlet openings 57, and according to the pressures set in the pressure and low-pressure chambers 11 resp. 15. Thereby the static pressure in the indifferent pressure zone in the skirting chambers rises, and thus the distance between the lining plate 13 and the mold belts 20, so that the mold belts rest softly on the string 32 over the entire length of the stope chamber 26. Thus, uniform cooling is achieved on both sides and over the entire the width of the string 32, so that heat stresses are reduced to

a minimum. Due to the associated, intense heat transfer, a correspondingly higher stopping performance is also achieved for the plant.

A further solution consists in dividing the low-pressure chamber 15 into several separate units over the length of the stop chamber, where each unit has a separate outlet. Thus, the liquid pressure can be set in each unit and thus in the corresponding part of the lining plate 13 by means of suitable regulating means,

so that the desired conditions regarding the pressure conditions in the dressing chambers can be realized, which are necessary to be able to increase the distance between the lining plate 13 and the mold belt 20 and thus achieve the most favorable stripping conditions.

Moreover, it can be prevented from forming

a shrinkage gap between the string 32 and the mold bands 20, the lining plates 13 being set convergently in relation to each other in the stop direction, corresponding to the expected shrinkage.

As the shrinking effect is significantly greater when the stopping material solidifies than during the subsequent cooling of the solidifying string, it is an advantage for strings with a thickness of more than 30 mm if the two opposite lining plates 13 are lined with a convex arch towards the stopping chamber 26 over its longitudinal direction, they local conditions, so that the narrowest point of the stop chamber is at the outlet. The necessary curvature can be realized in a simple way with a still flat base plate 16, as the height of the dress chamber elements 60 or 60' is changed correspondingly in the longitudinal direction of the stop chamber 26.

When the two mold bands 20 do not run parallel due to the curvature of the stop material 32 over the longitudinal direction of the stop chamber 26, elastic sealing side shields of temperature-resistant material are preferably used instead of the blocks 33, e.g. of fibrefrax, which can adapt to the converging shape of the stopping chamber 26.

For the production of a 25 mm thick strand of aluminum by means of a stopping device with two symmetrically arranged mold belts 20 and with a length of the stopping chamber 26 of 1 m, the following relations prove to be favorable:

In certain cases, e.g. if the stop chamber is not arranged vertically, a significantly lower pressure in the low-pressure chamber 15 may be necessary

to keep the die band at the desired short distance from the lining plate. To avoid excessively low pressures,

which can lead to cavitation in the dressing liquid, if the mold band consists of ferromagnetic material, a magnetic field can be placed on its back side, which further pulls the mold band towards the lining plate. For this purpose, it is advantageous to construct at least some of the lining plate's jacket chamber elements as magnets, preferably electromagnets. Fig. 9 shows in a similar section as fig. 3 a lining plate 13" with dress chamber elements 60" attached to the base plate 16,

which is longer than the elements 60 in fig. 3 and at least some of which are equipped with a magnetic winding 160 : and consist of ferromagnetic material. By feeding the magnetic windings or some of them with direct current, a magnetic field can be produced which pulls the mold strip 20 towards the lining plate and thus supports

the effect of the negative pressure fields that occur as the dressing liquid is sucked through the slits 58.

The magnetizable dress chamber elements 60", equipped with magnet windings 160, at least on a part of the lining plate surface can also serve another purpose, namely to set the mold belt 20 in mechanical oscillations perpendicular to the mold belt over at least the above-mentioned part of the lining plate surface. With such oscillations the heat transfer from the stop material to the mold belt can be reduced, which in many cases may be desired to reduce the thermal load of the mold belt or to prevent too rapid cooling of the stop material, at least in certain places in the stop chamber, especially at the entrance.

For this purpose, the magnetic windings 160 (or some of these) are electrically connected so that the mold band 20 is set into forced mechanical oscillations with a specific frequency and amplitude by means of periodic changes in the current strength. One can supply the magnetic windings 160 with alternating current, the strength of which decreases in the longitudinal direction of the stop line from the entrance, in order to induce oscillations in the mold band 20 with correspondingly decreasing amplitudes. The alternating currents can be fed to all the magnetic windings with the same phase, however, it can also be advantageous to feed the magnetic windings in adjacent rows of the dress chamber elements 60 with different phases, e.g. with counter-phase in alternating rows, so that the induced oscillations run in a wave-like fashion over the mold band (preferably lengthwise, i.e. in its direction of movement, but possibly also transversely or obliquely). The magnetic windings can be supplied with pure alternating current, but one can also additionally or instead supply direct current to individual magnetic windings, in order to achieve, as described, an overall attraction of the mold band 20 towards the lining plate 13".

Regardless of the material in the mold band 20,

can one also induce the described oscillations,

while adding the dressing liquid pulsatingly to i

at least some of the skirt chamber elements 60. For this purpose, it is appropriate to arrange a separate swinging valve in each inlet rudder 14, as shown in fig. 10 and 11.

Fig. 10 shows a simple, self-oscillating valve

with housing 114, where a movable valve body 115

is pressed against a valve seat 117 by a spring 116.

The spring 116 is dimensioned such that the pressure of the supplied cooling liquid lifts the valve body 115 from .

seat 117 when the pressure in the inlet pipe 14 has dropped below a certain value. The pressure in the inlet pipe rises again and the valve closes. With such friends-

until, however, it is very difficult to achieve a precise control of the oscillation frequency in the various dress chamber elements and control of the oscillation phases is not possible at all.

Arbitrarily steerable, on the other hand, is an electric one

controlled valve according to fig. 11. In this, the valve body 115' consists of ferromagnetic material and is moved by the magnetic field which is extended by a magnetic winding 118. The magnetic windings 118 in the different skirt chamber elements can be supplied with different alternating currents in the same way as in the magnetic windings 160 in fig. 9.

In the variant according to fig. 9, jet pumps are arranged in the connections to the inlet openings 57"

in the pockets 56 with the dressing fluid pressure chamber, whose suction sides are connected to the discharge slits 58, so that dressing fluid from the discharge slits is transferred directly into the inlet openings. The inlet opening 57<*> in each pocket 56 is formed by the exit opening of a bore 157 in the element 60". In front of the entrance opening to bore 157 is placed a coaxial nozzle 214, which is located at the end of the inlet pipe 14 which is connected to the pressure chamber.

The clothing liquid that comes out of the slits 58 partially flows through the holes 21 into the low-pressure chamber. The remaining amount of dressing liquid flows through radial holes 260, which are placed in the stem of the dressing chamber elements 60" at the same level as the outlet opening from nozzle 214. This liquid is sucked up by the jet pump action from the jet of liquid that came from nozzle 214 and is conveyed with this into bore 157.

In bore 157, a partial conversion of the kinetic energy in the jet from nozzle 214 into pressure energy follows, which leads to a corresponding increase in pressure in the direction of flow. Under the given pressure conditions in the pockets 56 in the dress chamber elements 60", an absolute pressure at the outlet of nozzle 214 results that is less than the pressure in the area between the dress chamber elements, so that, as already mentioned, liquid is sucked from this area through the radial holes 260.

The total cross-sectional area of the holes 260 in the dress chamber elements should preferably be at least four times as large as the cross-section of the bore 157. The cross-section of the bore 157 should at the exit 57 preferably make up 1 to 3.5% of the dress chamber surface,

and the length of the bore 157 preferably 5 to 10 times its diameter. The exit cross-section of the nozzle 214 preferably constitutes 25 to 50% of the entrance cross-section of the bore 157. The bore 157 can be made cylindrical or slightly divergent in the direction of flow.

Claims (43)

1. Method for dressing and lining a revolving die band on a device for continuous stopping of metal strands, where dressing liquid is supplied under pressure from several supply openings to the back side of the die band, which faces away from the stopping chamber, and is led away at a lower pressure, characterized by that the garment liquid is led into the back of the mold belt in several separate pockets with edges facing the mold belt, so that it completely fills the pockets and the space between these and the mold belt and flows out from each pocket between its edge and the mold belt, and is then led away at lower pressure. The outlet cross-section from each pocket is given by the distance between the mold belt and the pocket edge, so that a hydrostatically acting pressure field is built up in each pocket, which acts on the mold belt, and whose size depends on the above-mentioned distance and thus, together with the lower pressure prevailing outside the pockets, the encircling die band automatically maintains a practically constant distance from the edge of each pocket, so that the mold belt is not exposed to faults in the stope chamber area and at the same time is lined hydrostatically. 2. Method according to claim 1, characterized in that the dressing liquid is supplied to the pockets under turbulence in order to intensify the stripping of the die strip. 3. Method according to claim 1 or 2, characterized in that at least part of the area of the mold belt which is in contact with the stop material is set in mechanical oscillations perpendicular to the mold belt in order to reduce the heat transfer from the stop material to the mold belt. 4. Method according to claim .3, characterized in that the oscillations have a frequency between 20 and 500 sec ^. 5. Method according to claim 3 or 4, characterized in that the oscillations at least in some places, preferably at least in the entry area of the stop, exhibit an amplitude -5 -4 between 2-10 and 2'lo 6. Method according to one of claims 3 to 5, characterized in that the oscillations at least in some places, preferably at least in the entry area of the stopping section, exhibit a curve f and an amplitude h so that h'f 2 is greater than 0.5 m /sec 2. 7. Method according to one of claims 3 to 6, for a die band of ferromagnetic material, characterized in that the oscillations are induced by alternating magnetic fields acting on the die band. 8. Method according to one of claims 3 to 6, characterized in that the oscillations are induced by a pulsating supply of cooling liquid at least in some places. 9. Method according to one of claims 3 to 8, characterized in that the oscillations are induced so that they spread in a wave-like fashion over the mold band. 10. Method according to one of claims 1 to 9, characterized in that a magnetic field is placed on the back of the mold band, which pulls the mold band towards the edge of the above-mentioned pockets. 11. Method according to claim 10, characterized in that the magnetic fields are induced by electromagnets. 12. Device for dressing and lining a revolving mold band in a plant for continuous stopping of metal strands, with a lining plate arranged behind the mold band in the area of the stop chamber, with inlet openings connected to a dressing liquid pressure chamber and outlet openings for the dressing liquid connected to a low pressure chamber, characterized in that the lining plate (13) is divided into several individual dress chambers on the front, which face the mold band (20). Each of these dress chambers has a pocket (56) with an edge facing the mold belt, and in each pocket (56) at least one of the inlet openings (57) opens, while the drain openings (58, 21) open outside the pockets (56) on the front of the lining plate (13), so that the outlet cross-section from each pocket (56) is regulated by the distance between the mold band (20) and the edge of the pocket, in such a way that the mold liquid, which is supplied under pressure, completely fills the pockets (56) and that in each pocket is built up a hydrostatic pressure field which acts on the die band, and whose magnitude is dependent on the above-mentioned distance, and which, therefore, together with the lower pressure that prevails outside the pockets (56), automatically keeps the die band (20) at a practically constant distance from the edge of each pocket. 13. Device according to claim 12, characterized in that each of the dress chamber floats constitutes a maximum of 2 2 10 cm, preferably 1 to 6 cm. 14. Device according to claim 12 or 13, characterized in that the depth of the pockets (56) amounts to a few tenths of a millimeter to several millimeters and that the edge of the pockets is less than 0.5 mm wide. in 15. Device according to one of claims 12 to 14, characterized in that the inlet opening (57) in each pocket (56) is connected to the pressure chamber (11) by a separate inlet valve (14). 16. Device according to one of claims 12 to 15, on a mold band of ferromagnetic material, characterized in that electromagnets for alternating current (60", 160) are arranged vis-a-vis the stop chamber next to the mold band. 17. Device according to claim 16, characterized in that electromagnets (60", 160) are arranged in rows, where the current is supplied to side-ordered rows with different phase to induce wave-shaped forward-moving oscillations in the mold band (20). 18. Device according to claim 16 or 17, characterized in that the liner plate (13") consists of a base plate (16) and separate jacket chamber elements (60") attached to the base plate, and that the electromagnets are formed by at least some of the jacket chamber elements (60"), which is equipped with magnetic windings (160). 19. Device according to one of claims 12 to 15, characterized in that a swinging valve (115, 117; 115', 117) is arranged in at least one of the inlet lines for the dressing liquid. 20. Device according to claim 19, characterized in that the valves (115, 116, 117) are constructed, self-oscillating. 21. Device according to claim 19, characterized in that the valves (115', 117, 118) can be set electromagnetically in oscillations. 22. Device according to one of claims 12 to 15, characterized in that magnets are attached, (60", 160), preferably electromagnets, in or on the lining plate (13"), to pull the mold band (20) towards the lining plate (13"). 23. Device according to claim 22, characterized in that the lining plate (13") consists of a base plate (16) with separate dress chamber elements (60"), attached to the base plate, and that the magnets (60", 160) are formed by at least some of the dress chamber elements. 24. Device according to one of claims 12 to 23, characterized in that a jet pump (214, 260) is arranged in the connection between at least some of the inlet openings (57") with the liquid liquid pressure chamber (14), and whose suction side (260) is connected to the drain openings (58) so that coolant from the drain openings is transferred directly to the inlet openings (57"). 25. Device according to claim 24, characterized in that the lining plate (13") consists of a base plate (16) with separate dressing chamber elements (60") mounted on it, with intermediate slits (58), which form drainage openings for the dressing liquid and stand in connection with the low-pressure chamber (14) through holes (21) in the base plate (16), and that the jet pump (214, 260) in the individual dress chamber elements (60") is equipped with a nozzle (214) with a coaxial bore (157) between the nozzle -the outlet and the outlet of the inlet opening (57"). The inlet side of the bore (157) is connected to the space between the dress chamber elements with openings (260) at the base of the dress chamber elements (60"), so that kjfile fluid flows from this space into the dress chamber element, is entrained by the nozzle jet and is fed through the bore (157), and this leads to a pressure boil in the direction of flow in the bore as a result of the conversion of kinetic energy into pressure energy. 26. Device according to claim 25, characterized in that the bore (157) has an exit cross-section corresponding to 1 to 3.5% of the dress chamber surface, that the length of the bore (157) is 5 to 10 times as long as its diameter and that the exit cross-section of the nozzle ( 214) make up 25 to 50% of the entrance cross-section of the bore (157). 27. Device according to one of claims 12 to 26, characterized in that the dress chambers' drain openings (58) consist of slits on the surface of the lining plate (13), and that these are connected directly to the low-pressure chamber (15) with holes (21) in the lining plate (13). 28. Device according to one of claims 12 to 27, characterized in that the cross-section of the access opening (57) in each pocket (56) constitutes 0.5 to 3.5% of the dress chamber surface and the surface of the pocket (56) constitutes more than 50%, preferably over 70% of the total dress chamber surface and that the cross-section of the drain openings (58 or 21) in each dress chamber is twice to ten times as large as the area of the inlet opening (57). 29. Device according to one of claims 12 to 28, characterized in that the low-pressure chamber (15) is arranged immediately behind the connecting plate (13). 30. Device according to claim 29, characterized in that the pressure chamber (11) is located directly behind the low-pressure chamber (157i. , and the inlet openings (57) of the dress chambers are connected to the pressure chamber (11) through tilt-tilt valves (14), which lead through the low-pressure chamber (15 ). 31. Device according to claim 30, characterized in that side-arranged inlet rudders (14) have different lengths to prevent oscillations in the mold band (20). 32. Device according to claim 30 or 31, characterized in that the distance between the liner plate (13) and the opposite wall in the low-pressure chamber (15) constitutes between 5 and 25% of the square root of the skirt surface of the liner plate (13). 33. Device according to one of claims 12 to 32, characterized in that the lining plate (13) consists of a base plate (16) with separate boiler chamber elements (60, 60') attached to this. 34. Device according to claim 33, characterized in that the dressing chamber elements (60) are polygonal and of such a size that there are gaps (58) between adjacent elements (60) which form drainage openings for the dressing liquid, connected to the low-pressure chamber (15) through holes (21) ) in the base plate (16). The width of the slits (58) on the surface of the lining plate (13) is dimensioned such that the projection of the slit surface on the surface of the lining plate (13) for each dress chamber is twice to ten times the cross-section of the dress chamber's inlet opening (57). 35. Device according to claim 33, characterized in that the dress chamber elements (60) are round, but arranged in polygonal dress chambers, that the diameter of the dress chamber elements (60') constitutes a maximum of 98% of the distance between the centers of 2 adjacent dress chambers, but at least so large that the corresponding circular surface makes up more than 50% of the dress chamber surface, that there is also a side tap (61) for the supply of dress liquid from the pressure chamber (11) to the mold band (20) in the corners of the dress chambers, so that the mold band is cooled outside the round element (60') , and that the spaces between the elements (60') are connected to the low-pressure chamber (15) with drain openings (21), the total cross-sectional area of which is twice to ten times the area of the inlet openings (57). in 36. Device according to one of claims 12 to 35, characterized in that the mold band (20) has a thickness of 0.1 to 0.4 mm. 37. Device according to one of claims 12 to 36, characterized in that the drain openings (58, 21) for the cooling liquid in the lining plate (13) are gradually narrowed towards the exit of the stop chamber (26) in order to prevent a shrinkage gap from forming between the stop material and the mold band ( 20). 38. Device according to one of claims 12 to 37, characterized in that the low-pressure chamber (15) is divided into several separate units to prevent a shrinkage gap from forming between the stop material and the mold belt (20), where each unit has a separate outlet and the liquid pressure can be set in each unit by means of suitable regulating means so that the average static pressure in the dress chambers and thus the distance between the lining plate (13) and the mold belt (20) increases towards the outlet side of the stope chamber (26). 39. Device according to one of claims 12 to 38, with two opposite mold belts, characterized in that the lining plates (13) are set mutually convergent in the stop direction behind the mold belts (20). 40. Device according to one of claims 12 to 39, with two opposite mold bands, characterized in that the lining plates (13) are curved in the stop direction behind the mold bands (20), in order to adapt the cross-sectional progression of the stop chamber (26) to the change in thickness in the solidifying and cooling the stope. 41. Device according to one of the claims 12 to 40, characterized in that the mold band (20) immediately before the entrance to the stop stretch (26) is lined over several lining rollers (25), which are arranged across the width of the mold band (20) and arc-shaped in a row around it required angle. 42. Device according to one of claims 12 to 41, characterized in that the mold band (20) immediately after the exit to the stop stretch (26) is fed over several lining rollers (28), which are arranged across the width of the mold band (20) and arc-shaped in a row around it required angle. 43. Device according to claim 41 or 42, characterized in that the diameter of the lining rolls (25, 28) is 20 to 50 mm.