EP3429770B1 - Device and method for descaling a workpiece in motion - Google Patents

Description

The invention relates to a device and a method for descaling a workpiece which is moved relative to the device in one direction of movement. The workpiece is in particular a hot rolled product.

It is known in the prior art to spray water onto the surfaces of the workpiece at high pressure for descaling workpieces, in particular hot rolled material. To ensure that the surfaces of the workpiece are descaled without gaps, the high-pressure spray water is usually sprayed out of several nozzles of a scale washer. In this context a scale washer in a hot rolling mill is an assembly that is used to remove scale, i.e. H. of impurities from iron oxide, is provided from the surface of the rolling stock.

Out WO 2005/082555 A1 a scale washer is known with which a rolling stock which is moved relative to the scale washer is descaled by irradiation with high-pressure spray water. This scale washer comprises at least one row of nozzle heads with a plurality of nozzle heads that cross the width of the rolling stock, each nozzle head being driven in rotation by a motor about an axis of rotation perpendicular to the surface of the rolling stock. Furthermore, at least two nozzles which are arranged eccentrically with respect to the axis of rotation and which are arranged as close as possible in terms of construction to the circumference of the nozzle head are provided for each nozzle head. Such a scale washer is subject to the disadvantage that an energy input across the width of the rolling stock can have inhomogeneities, so that there are permanent temperature streaks on the rolling stock in the overlapping area of adjacent nozzle heads. Furthermore, the nozzles on the respective nozzle heads are arranged inclined outwards by an angle of attack, which in the Fig. 13 is illustrated. This means that the direction of spray of these nozzles at a Rotation of the nozzle heads about their axis of rotation is also aligned in the direction of the feed of the rolling stock. Such an alignment of the high-pressure spray water discharged from the nozzles is disadvantageous in that the jet of the spray water is ineffective and therefore makes no contribution to descaling the surface of the rolling stock.

Out WO 1997/27955 A1 A method for descaling rolling stock is known, in which a rotor descaling device is provided, by means of which a liquid jet is sprayed onto a surface of the rolling stock to be descaled. To ensure only a slight cooling of the rolling stock and to generate high jet pressures with a low operating fluid pressure, the liquid jet is formed intermittently, that is to say temporarily. Due to the interruption of the liquid jet one or more times, pressure peaks occur which have an effect on increasing the jet pressure, as a result of which an improvement in the descaling effect for the rolling stock is achieved. However, a control disk provided for this purpose, which is provided in fluid connection with a pressure medium supply line, disadvantageously increases the design effort for this descaling technique. Furthermore, there is a risk of increased material stress, particularly due to cavitation, when the pressure peaks are formed.

Out DE 10 2014 109 160 A1 a generic device and a generic method for descaling a workpiece are known, which is moved relative to the device in one direction of movement. For this purpose, a plurality of blasting nozzles are provided on a rotating rotor head in the form of a nozzle holder, liquid being applied or sprayed under high pressure from the blasting nozzles onto a surface of the rolling stock in such a way that the direction of radiation with which the liquid is sprayed out of the blasting nozzles always runs at an angle to the direction of movement of the rolling stock. This oblique alignment of the direction of radiation ensures that removed scale from the surface of the rolling stock to the side is transported away from the rolling stock. However, this is accompanied by a disadvantageous heavy contamination of the system or its surrounding area.

Out DE 19535789 A1 A generic device for descaling a workpiece according to the preamble of claim 1 and a corresponding method according to the preamble of claim 10 are known.

The invention has for its object to optimize the descaling of a workpiece with simple means and to reduce the required energy and amount of water.

This object is achieved by a device with the features defined in claim 1 and by a method with the features defined in claim 10. Advantageous developments of the invention are defined in the dependent claims.

A device according to the present invention is used for descaling a workpiece, preferably a hot rolling stock, which is moved in a direction of movement relative to the device, and comprises at least one rotor head which can be rotated about an axis of rotation and to which a plurality of blasting nozzles are attached, a liquid, in particular water, from the blasting nozzles. can be applied to the workpiece at an angle of attack at an angle to the surface of the workpiece. Here, the jet nozzles are attached to the rotor head in such a way that when the rotor head rotates about its axis of rotation, the spray direction of the liquid discharged from the jet nozzles, based on a projection into a plane parallel to the surface of the workpiece, is permanently opposite, ie at an angle of spray between 170 ° and 190 °, preferably at a spray angle of 180 °, to the direction of movement of the workpiece and the angle of attack remains constant for all jet nozzles. The device comprises a collecting device which is arranged upstream of the rotor head with respect to the direction of movement of the rolling stock, in such a way that both the liquid discharged from the jet nozzles after bouncing off the surface of the workpiece and the scale removed by means of the liquid from the surface of the workpiece can be specifically introduced into this collecting device.

In the same way, the invention also provides a method for descaling a workpiece, preferably a hot rolled product. Here, the workpiece is moved relative to a device in one direction of movement, this device having at least one rotor head which can be rotated about an axis of rotation and to which a plurality of jet nozzles are attached. While the rotor head is rotated about its axis of rotation, a liquid, in particular water, is applied or sprayed from the jet nozzles onto the workpiece at an angle of incidence at an angle to the surface of the workpiece. When the rotor head is rotated about its axis of rotation, the spray direction of the liquid discharged from the jet nozzles is permanently opposite in relation to a projection into a plane parallel to the surface of the workpiece, i. H. aligned at an angle of spray between 170 ° and 190 °, in particular at an angle of 180 °, to the direction of movement of the workpiece, the angle of attack remaining constant for all jet nozzles. Furthermore, both the liquid discharged from the jet nozzles after bouncing off the surface of the workpiece and the scale removed by means of the liquid from the surface of the workpiece are introduced into a collecting device in a targeted manner.

The invention is based on the essential finding that by means of the arrangement of the rotor head relative to the direction of movement of the workpiece and the attachment of the jet nozzles to the rotor head, it is possible to align the liquid dispensed from the jet nozzles permanently and preferably exactly in the opposite direction to the direction of movement of the workpiece, namely related on or in a projection of the spray direction of this liquid in a plane parallel to the surface of the workpiece. As a result, scaling is always removed from the surface of the workpiece by the liquid in the opposite direction to the movement of the workpiece, which contributes to a high efficiency in descaling. In this regard, it should be pointed out that effective descaling presupposes that the jet nozzles Work "schabend", which means that the spray direction of the jet nozzles is opposite to the direction of movement of the workpiece. The targeted introduction of the removed scale and the liquid that has ricocheted off the surface of the workpiece effectively prevents the removed scale from remaining on the surface of the workpiece and being rolled back into the surface during a new rolling process. In the same way, it is thereby achieved that system components of the device according to the invention are less or at best not soiled by scale and / or liquid splashing around aimlessly. In addition, it is pointed out that the fixed attachment of the jet nozzles to the rotor head leads to a significant structural simplification of the kinematics of the rotor head, because this means planetary gears or the like, which are otherwise provided according to the prior art for an additional rotation of the jet nozzles about their longitudinal axis, can be omitted.

In an advantageous development of the invention, the rotor head is arranged opposite the collecting device in such a way that the liquid is sprayed out in the direction of the collecting device, based on a projection into a plane parallel to the surface of the workpiece. This further optimizes the targeted introduction of removed scale and liquid, which bounces off the surface of the workpiece after being sprayed out of the jet nozzles, into the collecting device.

In an advantageous development of the invention, the positioning of the rotor head relative to the direction of movement of the workpiece and the attachment of at least one jet nozzle, preferably all jet nozzles, to the rotor head and are selected such that the spray direction of at least one jet nozzle, preferably all jet nozzles, in which the liquid is applied the workpiece is sprayed, runs permanently and opposite to the direction of movement of the workpiece, namely based on a projection of this spray direction in a plane parallel to the surface of the workpiece. As a result, the spray angle between the spray direction and the direction of movement of the workpiece, in a plane parallel to the surface of the workpiece, is in a range between 170 ° and 190 °, and preferably assumes the value of 180 °. In the same way as the arrangement of the rotor head opposite the collecting device, this advantageously leads to a targeted introduction of the removed scale and the liquid bounced off the surface of the workpiece into the collecting device, because the spray direction of the jet nozzles is not a component or a part contains, which is directed towards a side edge of the workpiece.

An optimal energy input is achieved for the liquid sprayed at high pressure on the surface of the workpiece in that a plurality of jet nozzles are attached to the rotor head at a different radial distance from its axis of rotation, with one jet nozzle having a greater radial distance from the Has axis of rotation, then a larger volume flow of liquid is applied than in comparison to a jet nozzle, which has a smaller radial distance from the axis of rotation. This can be achieved in a simple manner by selection of a suitable type of nozzle, so that a larger amount of liquid, i.e. a correspondingly larger amount of liquid, is obtained from a jet nozzle which is arranged radially further away from the axis of rotation of the rotor head. a larger volume flow is sprayed out. Such a configuration of a plurality of jet nozzles on the rotor head accordingly reduces the energy input for the liquid transversely to the direction of movement of the workpiece, ie. H. across its width, optimized.

In an advantageous development of the invention, the rotor head is arranged inclined such that its axis of rotation is inclined at an angle with respect to an orthogonal to the surface of the workpiece. Here, the jet nozzles are each firmly attached to the rotor head, so that the angle of attack, which the liquid sprayed out of the jet nozzles with an orthogonal includes the surface of the workpiece, remains constant the same. The jet nozzles are preferably attached to the rotor head in such a way that their longitudinal axes run parallel to the axis of rotation of the rotor head.

In an advantageous development of the invention, an arrangement of rotor heads and a jet nozzle arrangement can be provided, which are arranged one behind the other and in particular adjacent to one another with respect to the direction of movement of the workpiece.

In the case of an arrangement of rotor heads, the present invention is either a pair of rotor heads, in which a rotor head is provided above and below a workpiece, ie on the top and bottom thereof, or a pair of rotor modules, in which - above and below the workpiece - a plurality of rotor heads are combined next to one another and transversely to the direction of movement of the workpiece. In normal operation it can be provided that liquid is sprayed onto the workpiece only from the jet nozzles of the arrangement of rotor heads. In a special operation, the jet nozzles of the jet nozzle arrangement can then be switched on, so that liquid is also applied or sprayed onto the workpiece from the jet nozzles of this jet nozzle arrangement. In this case, the jet nozzles of both the arrangement of the rotor heads and the jet nozzle arrangement are used for descaling the workpiece. The design of the jet nozzle arrangement can differ structurally from the arrangement of rotor heads. The use of both arrangements in special operations is recommended for. B. for difficult to descaling steel grades, or for stubborn scale residues that can arise, for example, by resting on oven rolls. In such an embodiment, according to which only the jet nozzles of the arrangement of rotor heads are used in normal operation, the consumption of operating resources can advantageously be minimized. This applies in the same way in the event that a plurality of rotor heads - as explained - are combined into a rotor head module. This is because only one pair of rotor modules is in use during normal operation, and a further jet nozzle arrangement, which is arranged downstream in the direction of movement of the workpiece, for example, is activated as required.

Further advantages of the invention consist in the fact that the individual rotors of a rotor module can be switched individually and / or in groups without pressure and thus the application of the liquid can be adapted to the width of the workpiece transversely to the direction of movement.

In an advantageous development of the invention, a scale detection device connected to a control device can be provided, which is arranged downstream of the rotor head with respect to the direction of movement of the workpiece and close to it in order to be able to detect any remaining scale on the surface of the workpiece. On the basis of the signals from this scale detection device, the descaling quality of the workpiece is compared with a predetermined target specification by means of the control device and then, depending on this, a high-pressure pump unit, which is in fluid communication with the jet nozzles of the rotor head, is appropriately controlled or regulated.

The high-pressure pump unit can be controlled in such a way that a pressure with which liquid is sprayed out of the jet nozzles onto the surface of the workpiece is set as a function of the signals from the scale detection device. This means that the pressure for the liquid to be sprayed out is set just high enough to achieve an adequate descaling quality for the workpiece. If - as seen in the direction of movement of the workpiece - at least two jet nozzle arrangements are arranged one behind the other, it can be achieved by said control that a switchable jet nozzle arrangement is switched on in a suitable manner as a function of the signals of the scale detection device, which is the purpose of the special operation mentioned according to the invention corresponds. In comparison to a conventional two-row arrangement of rotor heads or spray bars, such a single-row arrangement, ie a single rotor head arrangement which is used in normal operation, results in substantial savings in operating media.

By the above adjustment of pressure, i. H. a reduction in pressure also results in a reduced abrasion effect of the liquid on all surrounding materials or system parts, which both reduces maintenance costs and also reduces wear on the jet nozzles themselves.

By installing a scale detection device and integrating it into a control or regulating device, the amount of water required for clean descaling of the workpiece can be suitably minimized by varying the pressure and / or the volume flow. This leads to a saving in energy for the provision of high-pressure water, and in the same way to a reduced cooling of the workpiece as a result of a reduced amount of liquid which is sprayed onto the workpiece.

In addition, it should be pointed out that a distance between the rotor head and the surface of the workpiece can be adjusted. This allows adaptation to different batches of workpieces with different heights. In addition, it is also possible to set this distance between the rotor head and the surface of the workpiece as a function of the signals from the scale detection device. For example, it can be provided in this way that, if the descaling quality is insufficient, the distance between the rotor head and the surface of the workpiece is reduced, so that a greater impact pressure is established on the surface of the workpiece in relation to the liquid sprayed thereon. Mutatis mutandis this also applies vice versa, according to which the distance of the rotor head to the surface of the workpiece, if the Descaling quality exceeds the predetermined target value, can be increased at least slightly.

Further advantages of the invention consist in the fact that, by collecting the scale detached from the surface of the workpiece, it is possible to reduce or even exclude scale errors by rolling in uncontrolled falling scale residues. Correspondingly, scale-free, clean surfaces with comparatively low water consumption are achieved for a workpiece, which saves a considerable amount of energy for generating the high-pressure water. The comparatively lower water consumption leads to an increased scale particle content of the water introduced into a collecting device. In other words, the water introduced into a collecting device has a greater degree of contamination because of a higher solids content of detached scale particles. Due to the reduced specific amount of water that is used for descaling the workpiece, the heating energy required for a furnace or the forming energy required for subsequent rolling of the workpiece can be considerably reduced. Due to the temperature saving, thinner final thicknesses can be generated for a workpiece or a hot rolled product, so that the product mix can be enlarged. In addition, the lifespan of oven rollers increases considerably at a lower oven temperature.

Exemplary embodiments of the invention are described in detail below on the basis of a schematically simplified drawing.

• Fig. 1 eine prinzipiell vereinfachte Seitenansicht einer erfindungsgemäßen Vorrichtung,
• Fig. 2 eine Seitenansicht eines Rotorkopfes der Vorrichtung von Fig. 1,
• Fig. 3a,
  Fig. 3b und
  Fig. 3c jeweils einen prinzipiellen Zusammenhang zwischen einer Spritzrichtung von Strahldüsen einer Vorrichtung gemäß Fig. 1 und einer Bewegungsrichtung, in der ein Werkstück an dieser Vorrichtung vorbeibewegt wird,
• Fig. 4 eine prinzipiell vereinfachte Draufsicht auf eine erfindungsgemäße Vorrichtung nach einer weiteren Ausführungsform,
• Fig. 5 eine vereinfachte Querschnittsansicht einer Auffangeinrichtung der Vorrichtung von Fig. 4,
• Fig. 6 eine vereinfachte Seitenansicht eines Rotorkopf-Paars, bei dem Rotorköpfe gemäß Fig. 2 jeweils an einer Oberseite und an einer Unterseite eines zu entzundernden Werkstücks angeordnet sind
• Fig. 7 eine vereinfachte Frontalansicht eines Rotormoduls, bei dem eine Mehrzahl von Rotorköpfen nebeneinander und quer zur Bewegungsrichtung des Werkstücks angeordnet sind,
• Fig. 8 eine mögliche Anordnung von Strahldüsen an einem Rotorkopf, zur Verwendung bei einer Vorrichtung gemäß Fig. 1 oder gemäß Fig. 4,
• Fig. 9a,
  Fig. 9b jeweils Spritzbilder, die sich mit einer auf ein Werkstück ausgespritzten Flüssigkeit auf der Oberfläche des Werkstücks ausbilden,
• Fig. 10 ein Ablaufdiagramm, gemäß dem die Erfindung in der Praxis eingesetzt wird, und
• Fig. 11, 12 jeweils Seitenansichten eines Rotorkopfes gemäß weiterer Ausführungsformen der Erfindung.

Show it:

• Fig. 1 a principally simplified side view of a device according to the invention,
• Fig. 2 a side view of a rotor head of the device of Fig. 1 ,
• Fig. 3a ,
  Fig. 3b and
  Fig. 3c in each case a basic relationship between a spray direction of jet nozzles according to a device Fig. 1 and a direction of movement in which a workpiece is moved past this device,
• Fig. 4 a basically simplified plan view of a device according to the invention according to a further embodiment,
• Fig. 5 a simplified cross-sectional view of a collecting device of the device of Fig. 4 ,
• Fig. 6 a simplified side view of a pair of rotor heads, according to the rotor heads Fig. 2 are each arranged on an upper side and on a lower side of a workpiece to be descaled
• Fig. 7 1 shows a simplified frontal view of a rotor module in which a plurality of rotor heads are arranged next to one another and transversely to the direction of movement of the workpiece,
• Fig. 8 a possible arrangement of jet nozzles on a rotor head, for use in a device according to Fig. 1 or according to Fig. 4 ,
• Fig. 9a ,
  Fig. 9b in each case spray patterns which form on the surface of the workpiece with a liquid sprayed onto a workpiece,
• Fig. 10 a flowchart according to which the invention is put into practice, and
• 11, 12 each side views of a rotor head according to further embodiments of the invention.

Below, with reference to the Figures 1 to 12 various embodiments of the invention are described in detail. In the figures, the same technical features are denoted by the same reference numerals. Furthermore, it is pointed out that the representations in the drawing are simplified in principle and in particular are shown without a scale. Cartesian coordinate systems are entered in some figures, for the purpose of spatial orientation of the embodiments according to the invention in relation to a workpiece to be treated and moved.

A device 10 according to the invention serves for descaling a workpiece 12 which is moved in a direction of movement X relative to the device 10. The workpiece 12 can be hot rolled material that is moved past the device 10.

In the embodiment of Fig. 1 The device 10 comprises a rotor head 14 which can be set in rotation about an axis of rotation R. The rotor head 14 is rotated about its axis of rotation R by motor means (not shown), for example by an electric motor. Jet nozzles 16 are attached to an end face of the rotor head 14 which faces the workpiece 12. A liquid 18 (in Fig. 1 simply symbolized with dashed lines) sprayed under high pressure onto a surface 20 of the workpiece 12 in order to descale the workpiece in a suitable manner. For this purpose, the jet nozzles 16 are in fluid communication with a high-pressure pump unit (not shown), by means of which the jet nozzles are fed with a liquid under high pressure. The liquid 18 is preferably water, without being restricted to water only.

In the embodiment of Fig. 1 The device 10 comprises a collecting device 22 which is arranged upstream of the rotor head 14 with respect to the direction of movement X of the workpiece 12. Such a collecting device 22 serves the purpose of absorbing both scale which has been removed from the surface 20 of the workpiece by means of the high-pressure liquid and the liquid which bounces off after contact with the surface 20 of the workpiece 12. In the representation of Fig. 1 are removed scale and the liquid bouncing off the surface 20 of the workpiece 10 is symbolized in a simplified manner by dash-dotted lines.

In connection with the collecting device 22, a lower guide plate 23.1 is provided, which is arranged between the rotor head 14 and the collecting device 22 and thereby directly adjoins an open area of the collecting device 22. The lower guide plate 23.1 is attached to the collecting device 22 in such a way that its free end is positioned directly above the workpiece 12 and at the same time forms an angle δ (with the surface 20 of the workpiece). Fig. 1 ) between 25-35 °. The lower guide plate 23.1 is preferably attached such that the angle δ to the surface 20 of the workpiece 12 assumes a value of 30 °.

The lower guide plate 23.1 is arranged in a corresponding manner to the angle δ of preferably 30 ° increasing in the direction of the collecting device 22. The lower guide plate 23.1 thus fulfills the function of a baffle surface and brings about a targeted entry of the scale and the liquid bounced off the surface 20 into the collecting device 22.

In addition, a cover device in the form of an upper cover plate 23.2 is provided, which extends from the collecting device 22 to directly on the rotor head 14 and thereby takes over the function of a cover. The distance between an edge of the upper cover plate 23.2, which directly adjoins the rotor head 14, is selected such that the section between the edge of the upper cover plate 23.2 and the rotor head 14 is free of scale particles. For the purposes of the present invention, “passage-free” means that scale particles, if they are detached from the surface 20 of the workpiece 12 as a result of the water sprayed out, cannot escape between the edge of the upper cover plate 23.2 immediately adjacent to the rotor head 14 and the rotor head 14 . Accordingly, the upper cover plate 23.2 prevents scale or liquid bouncing off the surface 20 of the workpiece 12 from escaping upward into the environment. Nevertheless, this ensures that air passes through the section between the upper cover plate 23.2 and the rotor head 14 can pass through, so that no back pressure forms below the upper cover plate 23.2 during operation of the device 10 according to the invention.

Below are with reference to the Fig. 2 and 3rd further relationships for the arrangement of the rotor head 14 and the jet nozzles 16 attached to it explained.

The jet nozzles 16 are fixedly attached to an end face of the rotor head 14 opposite the workpiece 12. Here, the longitudinal axes L of the jet nozzles 16 are aligned parallel to the axis of rotation R of the rotor head 14. The spray direction S also runs accordingly (cf. Fig. 2 ), in which the liquid is sprayed out of the jet nozzles 16, parallel to the axis of rotation R of the rotor head 14.

The axis of rotation R is oblique with respect to an orthogonal to the surface 20 of the workpiece 12 at an angle γ ( Fig. 2 ) arranged inclined. Attaching the jet nozzles 16 to the rotor head 14, in which, as explained, the longitudinal axes L of the jet nozzles run parallel to the axis of rotation R, results in an angle of attack α (cf. Fig. 2 ), with which the liquid 18 sprayed from the jet nozzles 16 hits the surface 20 of the workpiece. This angle of attack α corresponds to an angle between the spray direction S of the liquid 18 and an orthogonal to the surface 20 of the workpiece 12. Because of the parallel alignment of the longitudinal axes L of the jet nozzles 16 with the axis of rotation R, the angle of attack α is in the embodiment of Fig. 2 equal to the angle of inclination γ of the axis of rotation R.

The rotor head 14 is adjustable in height. This means that a distance A, which an intersection of the axis of rotation R has with the end face of the rotor head 14 to the surface 20 of the workpiece 12 ( Fig. 2 ), can be changed if necessary. In the sense of the present invention, this distance A is to be understood as the spraying distance. When reducing this Distance A increases the resulting impact pressure of the liquid 18 on the surface 20 of the workpiece 12. The height adjustability for the rotor head 14 is in the Fig. 2 Simplified symbolized by the arrow "H", and can be realized by a height-adjustable bracket to which the rotor head 14 is attached. Details of an adjustment of this distance A are explained in detail below.

The Fig. 3 illustrates a relationship between the direction of spray S, with which the liquid 18 is sprayed out of the jet nozzles 16, and the direction of movement X, with which the workpiece 12 is moved past the device 10 or its rotor head 14. This is clarified in detail Fig. 3 a projection of the spray direction S into a plane parallel to the surface 20 of the workpiece 12. In the example of Fig. 3a is the spray direction S, with which the liquid 18 is discharged from a nozzle mouth 17 of a jet nozzle 16, exactly opposite to the direction of movement X, ie oriented at a spray angle β of exactly 180 ° to the direction of movement X. As a result, the spray direction S of the liquid 18, when it is permanently sprayed onto the workpiece 12 under high pressure, has no portion which points in the direction of a lateral edge of the workpiece 12. This ensures that the liquid 18 is always sprayed in the direction of the collecting device 22 from the jet nozzles 16 onto the surface 20 of the workpiece. As a result, the removed scale, in conjunction with the liquid 18 that has rebounded from the surface 20 of the workpiece 12, is then introduced into the collecting device 22 in a targeted manner.

According to the examples of 3b and 3c it is also possible that the spray angle β is greater or less than 180, for example 170 ° or 190 °, or falls within a range of values between 170 ° and 190 °. This means that the spray direction S then does not run exactly opposite to the direction of movement X, but rather includes an angle with the direction of movement X which - as explained At this point, it is pointed out separately that the above-described orientation of the spray direction S, according to the representations according to 3a, 3b and 3c , remains unchanged or constant during a rotation of the rotor head 14 about its axis of rotation R. The same applies to the angle of attack a.

With respect to the rotor head 14 according to Fig. 2 is pointed out that this rotor head 14 that of Fig. 1 can correspond. In deviation from this, it is also possible for the present invention to design the rotor head 14 according to FIG Fig. 2 without providing a catch device 22.

A further embodiment for a device 10 according to the invention is shown in FIG Fig. 4 shown, namely in a basically simplified top view. An arrangement 14.1 of rotor heads and a jet nozzle arrangement 14.2 are arranged one behind the other in relation to the direction of movement X of the workpiece 12. The jet nozzle arrangement 14.2 can in the Fig. 4 shown example can also be designed in the form of an arrangement of rotor heads, wherein - for this example - these arrangements 14.1, 14.2 of rotor heads are referred to below as "rotor head arrangements". Each of these rotor head arrangements 14.1 and 14.2 is assigned its own catch device 22, which is arranged upstream of an associated rotor head with respect to the direction of movement X of the workpiece 12. In principle, a different type of jet nozzle can also be provided instead of the rotor head arrangement 14.2.

The top view of Fig. 4 makes it clear once again that the spray direction S, with which the liquid 18 is discharged from the jet nozzles 16 attached to a rotor head 14, does not have a portion which points in the direction of a lateral edge 13 of the workpiece 12, but instead directly to an associated collecting device 22 is directed.

The degree of pollution of the water is due to the reduced amount of water applied in accordance with the invention with a simultaneously improved effectiveness with scale residues or corresponding solid particles, so that a different design of the collecting device is recommended.

The entry of removed scale and of liquid, which bounces off the surface 20 after contact with the workpiece 12, into a respective collecting device 22 is, as explained above, supported by the lower guide plate 23.1, which increases gently at an angle δ, and is in the Fig. 4 symbolically symbolized by the arrows "E".

Further details of the collecting device 22 result from the Fig. 5 which shows a cross sectional view thereof.

A bottom surface 25 of the collecting device 22 is laterally inclined downwards. When representing Fig. 5 the vertical line of symmetry is aligned with a center of the workpiece 12. As a result, the bottom surface 25 of the collecting device 22, starting from its center, then falls off towards the side edges 24, and consequently also scale and liquid which are introduced into the collecting device 22 are moved in the direction of the side edges 24.

The catcher 22 is connected to a drain pipe 26, e.g. on both side wheels 24. Due to the gravitation, cleaning liquid and removed scale are discharged from the collecting device 22, e.g. in a (not shown) conveyor trough, in which the drain pipe 26 opens.

The discharge of cleaning liquid and scale from the collecting device 22, namely through the drain pipe 26, can be optimized by a conveying device 27 by means of which cleaning liquid and scale within the collecting device are conveyed in the direction of an opening of the drain pipe 26 or in the direction of the lateral edges 24 will. For this purpose, the Conveying device 27, e.g. rinsing nozzles 28 ( Fig. 5 ), from which a fluid, for example a liquid or a gas or a mixture thereof, is discharged obliquely to the bottom surface 25. As an alternative or in addition to such flushing nozzles 28, it is also possible for the conveying device 27 to have mechanical components, for example scraper elements, conveying screws or the like, by means of which the liquid and / or the scale are conveyed in a targeted manner in the direction of an opening of the outlet pipe 26.

Below are with reference to the Fig. 6 and 7 possible arrangements of rotor heads shown and explained, for example in the embodiment of Fig. 4 can be used.

Fig. 6 shows a side view of a pair of rotor heads 29, in which a rotor head 14 is provided above and below the workpiece 12, ie both on the top and on the bottom thereof. It can be seen that the rotor head 14, which is arranged below the workpiece 12, is positioned downstream of the rotor head 14, which is arranged above the workpiece 12, with respect to the direction of movement X of the workpiece 12. This is so that, for example, liquid 18, which is sprayed from the jet nozzles 16 of the rotor head 14 arranged below the workpiece 12, does not collide with the rotor head 14 arranged above the workpiece 12 if there is no workpiece or strip material between these two rotor heads. The in Fig. 6 shown offset between the rotor heads arranged above and below the workpiece 12 does not change the fact that these two rotor heads, in the sense of the present invention, are to be understood as a pair of rotor heads 29. In this regard, it is understood that the in Fig. 4 14.1 and 14.2 shown can each be such a pair of rotor heads.

Fig. 7 shows a frontal view of rotor head modules 30, which are respectively provided above and below the workpiece 12 and thereby a pair of rotor modules 31 form. Specifically, the respective rotor head modules 30 consist of a plurality of rotor heads 14 which are arranged next to one another and transversely to the direction of movement X of the workpiece. Deviating from the representation in the Fig. 7 Less or more than three rotor heads 14 can also be combined to form a rotor module 30.

For the representation of Fig. 6 it is additionally pointed out that this is also a side view of a pair of rotor modules 31 according to FIG Fig. 7 can act, in each case only the rotor head 14 lying foremost in the paper plane can be seen on the top and bottom of the workpiece.

Regarding the embodiments according to the Figures 6 and 7 it is pointed out that the individual rotor heads 14 are connected to a common pressurized water line D, the pressurized water line D being connected to the high-pressure pump unit. This ensures that the jet nozzles 16 attached to the rotor heads are supplied with high-pressure water.

In the embodiment according to Fig. 4 In contrast to the illustration shown, it can also be provided that instead of the individual rotor heads 14.1 and 14.2, which are arranged one behind the other in relation to the direction of movement X, rotor modules 30 are also provided, namely - because of the arrangement above and below the workpiece 12 - in the form of Rotor module pairs 31 according to Fig. 7 .

In a rotor module 30 according to the embodiment of FIG Fig. 7 the width of a workpiece 12, ie in a direction transverse to its direction of movement X, is covered by a plurality of rotor heads 14 as shown. In other words, the width of such a rotor module 30 essentially corresponds to a width of the workpiece 12. This leads to the advantage that, in contrast to, for example, only a single rotor head, the diameter of which corresponds to the width of the Workpiece 12 corresponds, then the diameter of the individual rotor heads of a rotor module 3 can be smaller, combined with the advantage that higher speeds can then be set for these rotor heads, possibly also for adaptation to high rolling speeds or high feed speeds for the workpiece.

It is advantageous if the individual rotors of a rotor module can be switched off individually and / or in groups without pressure and thus the application of the liquid is adapted to the width of the workpiece.

Fig. 8 symbolizes an attachment of a plurality of jet nozzles 16 on one end face of a rotor head 14. In the example of Fig. 8 three jet nozzles 16.1, 16.2 and 16.3 are provided, each having a different distance s from the axis of rotation R of the rotor head 14. When representing Fig. 8 The axis of rotation R runs perpendicular to the plane of the drawing.

The different distances between the respective jet nozzles 16.1, 16.2 and 16.3 are shown in Fig. 8 each designated s ₁ , s ₂ , and s ₃ , with the proviso: s ₁ > s ₂ > s ₃ . In such an arrangement of jet nozzles, each with a different radial distance from the axis of rotation R, it is provided that a larger volume flow of liquid is sprayed out from a jet nozzle which has a greater radial distance from the axis of rotation R than in comparison to a jet nozzle which has a smaller distance to the axis of rotation. With respect to the three nozzles 16.1, 16.2 and 16.3 according to Fig. 8 the relationship then applies to the volume flow discharged from these nozzles: V̇ ₁ > V̇ ₂ > V̇ ₃ . As a result, a uniform energy input is achieved on the surface 20 of the workpiece 12 transverse to its direction of movement X for the liquid discharged from the jet nozzles 16.1, 16.2 and 16.3.

The just in relation to the representation of Fig. 8 the relationships explained also apply to a number of jet nozzles of greater or less three, namely, in any case for several jet nozzles, each of which is at a different distance from the axis of rotation R of the rotor head 14. It is also noted that the example of Fig. 8 also applies to all rotor heads 14 which in the Fig. 1-7 are shown and explained.

For the invention, a scale detection device 32 can be provided, which is arranged downstream of a rotor head 14 or a pair of rotor heads 29 or a pair of rotor modules with respect to the direction of movement X of the workpiece 12, for simplification only reference being made to a rotor head 14 below without being seen as a limitation. In the embodiment of Fig. 4 Such a scale detection device 32 is arranged downstream of the rotor head 14.2. Regardless of the number of rotor heads that can be arranged one behind the other in the present invention with respect to the direction of movement X of the workpiece 12, it is important for the scale detection device 32 that it is in close proximity and downstream to a rotor head (for example rotor head 14.2 according to FIG Fig. 4 ) the device 10 is arranged, at least before the workpiece 12 z. B. is subjected to a new rolling process.

The scale detection device 32 is connected in terms of signals to a control device 34 ( Fig. 1 , Fig. 4 ). By means of the scale detection device 32, it is possible to reliably detect or detect possible remaining scale on the surface 20 of the workpiece 12 after the liquid 18 has been sprayed onto the workpiece 12. For this purpose, the scale detection device 32 extends completely over a width of the workpiece 12. Furthermore, it should be pointed out that a scale detection device 32 can be provided above and below the workpiece 12, that is to say on its upper side and on its lower side. Accordingly, by means of the scale detection device 32 it is possible to detect possible residual scale on both surfaces of the workpiece 12.

In the representations of Fig. 1 and Fig. 4 it is shown symbolically that a rotor head 14 is also connected to the control device 34 for signaling purposes. This means that by means of the control device 34 it is possible to suitably change the pressure with which the liquid sprayed from the jet nozzles 16 impinges on a surface 20 of the workpiece 20. Such a change in the impact pressure of the liquid can take place, for example, by switching a pump of the high-pressure pump unit on or off, to which the pressurized water line D for the jet nozzles 16 is connected. Additionally or alternatively, it can be provided that the high-pressure pump unit, with which the pressure supply for the jet nozzles 16 is guaranteed, is equipped with a frequency regulator in order to achieve an even better adaptation of the desired pressure for the jet nozzles 16.

Alternatively and regardless of the provision of a scale detection device 32, it is possible for the present invention that a rotor head 14 is connected to the control device 34 for signaling purposes. Correspondingly, the speed at which the rotor head 14 is rotated about its axis of rotation R can also be adjusted, for example, as a function of the feed rate at which the workpiece is moved past the device 10 in its direction of movement X by means of the control device 34. By means of such an adaptation of the speed of rotation for the rotor head 14, in particular to the feed speed of the workpiece 12 in its direction of movement X, an optimal energy input is achieved for the liquid 18 sprayed onto the surface 20 of the workpiece 12, namely along the direction of movement X. Such an optimal adaptation of the The speed of rotation of the rotor head 14 at the feed speed of the workpiece 12 is shown in the spray pattern Fig. 9a shown, which shows a section of a surface 20 of the workpiece 12 in a plan view. In contrast, the representation of Fig. 9b a non-optimal adaptation of the speed of the rotor head 14 to the feed speed of the workpiece 12. By means of the invention it is possible to produce a spray pattern according to the representation of Fig. 9b to avoid.

The invention now works as follows:
For a desired descaling of the surfaces 20 of a workpiece 12, this workpiece is moved in a movement direction X relative to the device 10 according to the invention. Here, rotor heads 14 of the device 10 are preferably provided both on an upper side and on an underside of the workpiece 12, according to the embodiment of FIG Fig. 6 . Descaling of the workpiece 12 is achieved in that a liquid 18 is sprayed from the jet nozzles 16 attached to a rotor head 14 onto the surfaces 20 of the workpiece 12 under high pressure. As a result of the above-described alignment of the jet nozzles 16 and the resulting spray direction S for the liquid 18, removed scale, in conjunction with the liquid bouncing off the surface 20 of the workpiece 12, is introduced into the collecting device 22 in a targeted manner.

Means (not shown) are provided, by which the control device 34 receives information regarding the feed speed of the workpiece 12 in its direction of movement X. On the basis of this, a desired rotational speed for a rotor head 14 can be set by means of the control device 34, namely in adaptation to the feed speed of the workpiece 12. Such an adaptation is also possible during production operation if there are fluctuations in the feed speed for the workpiece 12 . In terms of programming, the control device 34 can be set up such that the speed of rotation of a rotor head 14 is also adjusted in a controlled manner.

On the basis of the signals from the scale detection device 32, the pressure with which the jet nozzles 16 attached to a rotor head 14 are fed with the liquid 18 can be adjusted or adjusted to a predetermined value. This means that, for example, the pressure of the liquid 18 provided for the jet nozzles 16 is set just high enough that a sufficient descaling quality is achieved, which is then achieved by means of the Scale detection device 32 can be monitored. This makes it possible to save water and energy. If, on the other hand, it should be recognized by the control device 34, based on the signals generated by the scaling detection device 32, that the descaling quality falls below a certain target value, this can be done, for example, by a suitable pressure increase, by switching on a pump and / or by switching on an additional descaling unit in the form of a pair of rotor heads 29 or a pair of rotor modules 31. Such an operational flow according to the present invention is also in the flow chart of FIG Fig. 11 illustrated.

In addition and / or alternatively, the impact pressure can be changed by adjusting the height of the rotor head arrangement. This height adjustment is in the Fig. 2 , as already explained there, symbolized by the arrow "H". The distance A ( Fig. 2 ), which a rotor head 14 has from the surface 20 of the workpiece 12, is adjusted or changed as a function of the signal values of the scale detection device 32. For example, this distance A can be reduced if the descaling quality of the surface 20 of the workpiece 12 is judged to be unsatisfactory, the impact pressure of the liquid 18 on the surface 20 of the workpiece 12 increasing as a result of the reduced distance A. Conversely, this means that, at least as long as the descaling quality remains sufficiently high and a predetermined target value has been reached for this, the distance A can also be increased.

To carry out the present invention, it is advisable to tilt the rotor head (cf. angle γ in Fig. 2 ) and to choose the attachment of the jet nozzles 16 to the rotor head in such a way that the angle of attack a lies in a range from 5 ° to 25 ° and preferably assumes a value of 15 °.

Finally, it should be pointed out that for the present invention, a rotor head 14.3 as shown in FIG Fig. 11 and / or a rotor head 14.4 as shown in Fig. 12 can be used.

With the rotor head 14.3 according to Fig. 11 Its axis of rotation R runs perpendicular to the surface 20 of the workpiece 12 to be descaled, the jet nozzles 16 being mounted inclined on one end face of the rotor head 14.3. When the rotor head 14.3 rotates about its axis of rotation R, the jet nozzles 16 are rotated simultaneously and synchronously about their longitudinal axis L such that the angle of attack α in each case remains constant with respect to the surface 20. This is achieved via a planetary gear 36, which is integrated in the rotor head 14.3.

With the rotor head 14.4 according to Fig. 12 The axis of rotation R likewise runs perpendicular to the surface 20 of the workpiece 12, the jet nozzles 16 being attached to the rotor head 14.4 with their longitudinal axis L parallel to the axis of rotation R. The jet nozzles 16 have a suitably designed outlet opening on their respective nozzle mouth 17, through which a deflection of the ejected liquid 18 is achieved, as a result of which the in Fig. 13 shown angle of attack α results. This angle of attack α remains constant during a rotation of the rotor head 14.4 about its axis of rotation in that the jet nozzles 16 are rotated about their longitudinal axis L synchronously with the rotation of the rotor head 14.4 by means of a planetary gear.

It goes without saying that the rotor heads 14.3 and 14.4. can also be used in the manner of a pair of rotor heads 29 and / or in the manner of a pair of rotor modules 31, as shown in Fig. 6 or in Fig. 7 .

When using the rotor heads 14.3 and 14.4, the same spray direction S can be achieved for the sprayed-out liquid 18 as in the illustration of FIG Fig. 3a is shown. Alternatively, it is when using a Rotor head 14.3 or 14.4 also possible to set a spray direction S for at least one jet nozzle attached to such a rotor head that the resulting spray direction S forms an angle of 170 ° with the direction of movement X ( Fig. 3b ) or 190 ° ( Fig. 3c ), or includes an angle that is between 170 ° -180 ° or 180 ° -190 °.

For example, it is possible that the in Fig. 8 shown rotor head according to a rotor head 11 or 12 acts. It can then be provided that the spray direction S of the jet nozzle 16.2 at a spray angle β of 180 ° ( Fig. 3a ) is aligned, the spray direction S of the jet nozzle 16.1 at a spray angle β of 170 ° ( Fig. 3b ) and the spray direction S of the jet nozzle 16.3 at a spray angle β of 190 ° ( Fig. 3c ) are aligned. With such an arrangement of jet nozzles on a rotor head, it is possible to further increase the descaling quality for the workpiece 12, because any depressions that can form on the surface 20 of the workpiece are also effectively descaled by avoiding splash shadows.

Incidentally, it is pointed out that the rotor heads 14.3 and 14.4 according to Fig. 11 respectively. Fig. 12 in the same way as the rotor head 14 ( Fig. 2 ) in the embodiments according to Fig. 1 or Fig. 4 can be used. The mode of operation for descaling the workpiece 12 remains unchanged, so that reference can be made to the above explanations in order to avoid repetition.

Reference symbol list

10th

contraption

12

workpiece

14

Rotor head

16

Steel nozzle

16.1

Steel nozzle

16.2

Steel nozzle

16.3

Steel nozzle

18th

liquid

20th

surface

22

Catch direction

23.1

Covering device

23.2

Covering device

26

Drain pipe

27th

Conveyor

28

Rinsing nozzle

29

Rotor head pair

31

Pair of rotor modules

32

Ignition detection device

α

Angle of attack

β

Spray angle

γ

angle

L

Longitudinal axis

R

Axis of rotation

S

Spray direction

V ₁

Volume flow

V ₂

Volume flow

V ₃

Volume flow

X

Direction of movement

Claims (18)

1. Device (10) for descaling a workpiece (12), preferably a hot rolling material, moved relative to the device (10) in a movement direction (X), comprising
   at least one rotor head (14), which is rotatable about an axis (R) of rotation and on which a plurality of jet nozzles (16) is mounted, wherein a liquid (18), particularly water, can be issued from the jet nozzles (16; 16.1, 16.2, 16.3) onto the workpiece (12) at an angle (α) of incidence inclined with respect to an orthogonal to a surface (20) of the workpiece (12), and
   a collecting device (22) is provided, which is so arranged upstream of the rotor head (14) with respect to the movement direction (X) of the rolling material that not only the liquid (18) issued from the jet nozzles (16; 16.1, 16.2, 16.3) after rebounding from the surface (20) of the workpiece (12), but also the scale removed from the surface (20) of the workpiece (12) by means of the liquid (18) can be introduced in targeted manner into the collecting device (22),
   characterised in that
   the jet nozzles (16; 16.1, 16.2, 16.3) are so mounted on the rotor head (14) that on rotation of the rotor head (14) about its axis (R) of rotation the spray direction (S) of the liquid (18) issued from the jet nozzles (16; 16.1, 16.2, 16.3) is oriented to be permanently opposed - with respect to a projection in a plane parallel to the surface (20) of the workpiece (12) - to the movement direction (X) of the workpiece (12), i.e. at a spray angle (β) between 170° and 190°, preferably at a spray angle (β) of 180°; and in that case the angle (α) of incidence remains constant for all jet nozzles (16).
2. Device (10) according to claim 1, characterised in that the jet nozzles (16; 16.1, 16.2, 16.3) of the plurality are mounted on the rotor head (14) at radial spacings (s₁; s₂; s₃) of different size with respect to the axis (R) of rotation thereof, wherein a greater volume flow (V₁; V̇₂; V̇₃) of liquid (18) can be issued from a jet nozzle (16; 16.1, 16.2, 16.3) having a greater radial spacing from the axis (R) of rotation than by comparison with a jet nozzle having a smaller radial spacing from the axis (R) of rotation.
3. Device (10) according to claim 1 or 2, characterised in that the rotor head (14) is so arranged relative to the collecting device (22) that the liquid (18) is issued from the jet nozzles (16; 16.1, 16.2, 16.3) exclusively in the direction of the collecting device (22).
4. Device (10) according to any one of claims 1 to 3, characterised in that the positioning of the rotor head (14) relative to the movement direction of the workpiece (12) and the mounting of at least one jet nozzle (16; 16.1, 16.2, 16.3), preferably all jet nozzles (16; 16.1, 16.2, 16.3), on the rotor head (14) are so selected that the spray direction (S) of the at least the one jet nozzle (16; 16.1, 16.2, 16.3), preferably all jet nozzles (16; 16.1, 16.2, 16.3), at which the liquid (18) is issued extends, in the case of a projection in a plane parallel to the surface (20) of the workpiece (12), exactly opposite to the movement direction (X) and thus the spray angle (β) between the spray direction (S) and the movement direction (X) is exactly 180°.
5. Device (10) according to any one of claims 1 to 4, characterised in that the collecting device (22) is provided with at least one outlet pipe (26) by which the cleaning liquid and removed scale can be conducted away from the collecting device (22).
6. Device (10) according to any one of claims 1 to 5, characterised in that the collecting device (22) is equipped with a conveying device (27), by means of which the removed scale within the collecting device (22) is transportable in the direction of an opening of the outlet pipe (26), preferably in that the conveying device (27) comprises at least one rinsing nozzle (28) from which a fluid can be issued.
7. Device (10) according to any one of claims 1 to 6, characterised in that individual rotors of a rotor module can be switched off free of pressure individually and/or in groups for adaptation of the application of the liquid (18) transversely to the movement direction (X) of the workpiece (12).
8. Device (10) according to any one of claims 1 to 7, characterised in that a cover device (23.2) is arranged between the collecting device (22) and the rotor head (14) and extends from the collecting device (22) directly up to the rotor head (14) in such a way that a section between the rotor head (14) and an edge of the cover device (23.2) is free for passage with respect to scale particles.
9. Device (10) according to any one of claims 1 to 8, characterised in that the rotor head (14) is inclined by its axis (R) of rotation with respect to an orthogonal to a surface (20) of the workpiece (12) obliquely at an angle (γ), wherein the jet nozzles (16) are respectively fixedly mounted on the rotor head (14), preferably in that the jet nozzles (16; 16.1, 16.2, 16.3) are arranged with the longitudinal axes (L) parallel to the axis (R) of rotation of the rotor head (14).
10. Method of descaling a workpiece (12), preferably a hot-rolling material, which is moved in a movement direction (X) relative to a device (10) with at least one rotor head (14), which is rotatable about an axis (R) of rotation and on which a plurality of jet nozzles (16; 16.1, 16.2, 16.3) is mounted, wherein a liquid (18), particularly water, is issued from the jet nozzles (16; 16.1, 16.2, 16.3), while the rotor head (14) is rotated about its axis (R) of rotation, onto the workpiece (12) at an angle (α) of incidence inclined with respect to the surface (20) of the workpiece (12), wherein not only the liquid (18), which is issued from the jet nozzles (16; 16.1, 16.2, 16.3), after rebounding from the surface (20) of the workpiece (12), but also the scale removed from the surface (20) of the workpiece (12) by means of the liquid (18) are introduced in targeted manner into a collecting device (22),
    characterised in that
    on rotation of the rotor head (14) about its axis (R) of rotation the spray direction (S) of the liquid (18), which is issued from the jet nozzles (16; 16.1, 16.2, 16.3), is oriented to be permanently opposed to the movement direction (X) of the workpiece (12) - with respect to a projection in a plane parallel to the surface (20) of the workpiece (12) - i.e. at a spray angle (β) between 170° and 190° and particularly at a spray angle (β) of exactly 180° and in that case the angle (α) of incidence remains constant for all jet nozzles (16).
11. Method according to claim 10, characterised in that the rotational speed at which the at least one rotor head (14) is rotated about its axis (R) of rotation is adapted by means of a control device (34) to the speed of advance at which the workpiece (12) is moved in the movement direction (X), preferably such that the adaptation of the rotational speed of the rotor head (14) to the speed of advance of the workpiece (12) is carried out in regulated manner.
12. Method according to claim 10 or 11, characterised in that volume flows of liquid (18) of different magnitude are sprayed from jet nozzles (16; 16.1, 16.2, 16.3), which are mounted on the rotor head (14) respectively at radial spacings (s₁; s₂; s₃) of different size from the axis (R) of rotation thereof, of the plurality, wherein a greater volume flow (V̇₁; V̇₂; V̇₃) of liquid (18) is sprayed from a jet nozzle (16; 16.1, 16.2, 16.3) having a greater radial spacing with respect to the axis (R) of rotation than by comparison with a jet nozzle having a smaller radial spacing from the axis (R) of rotation.
13. Method according to any one of claims 10 to 12, characterised in that a rotor head arrangement (14.1) and a jet nozzle arrangement (14.2) are provided, wherein the rotor head arrangement (14.1) respectively is formed from a rotor head pair (29) or from a rotor module pair (31), wherein the rotor head arrangement (14.1) and the jet nozzle arrangement (14.2) are arranged in succession and, in particular, adjacent to one another with respect to the movement direction (X) of the workpiece (12), wherein in a normal operation liquid (18) is issued only from the jet nozzles (16; 16.1, 16.2, 16.3) of the rotor head arrangement (14.1) onto the workpiece (12), wherein in a special operation the jet nozzles (16; 16.1, 16.2, 16.3) of the jet nozzle arrangement (14.2) are switched on so that liquid (18) is also issued from the jet nozzles (16; 16.1, 16.2, 16.3) of the jet nozzle arrangement (14.2) onto the workpiece (12) and correspondingly, for descaling the workpiece (12), then not only the rotor head arrangement (14.1), but also the jet nozzle arrangement (14.2) are used.
14. Method according to any one of claims 10 to 13, characterised in that a scale detection device (32), which is arranged downstream of the rotor head (14) with respect to the movement direction (X) of the workpiece (12), and a control device (34), with which the scale detection device (32) and the at least one rotor head (14) are in signal connection, are provided, wherein residual scale on the surface (20) of the workpiece (12) is detected by the scale detection device (32), wherein the control device (34) is programmed in such a way that on the basis of the signals of the scale detection device (32) the quality of descaling of the workpiece (12) is compared with a predetermined target preset and in dependence thereon a high-pressure pump unit which is in fluid connection with the jet nozzles (16; 16.1, 16.2, 16.3) of the rotor head (14) is controlled, preferably regulated.
15. Method according to claim 14, characterised in that the jet nozzles (16; 16.1, 16.2, 16.3) of the jet nozzle arrangement (14.2), which can be switched on, is set into operation in dependence on the signals of the scale detection device (32), namely into the special operation.
16. Method according to claim 14 or 15, characterised in that by means of activation of the high-pressure pump unit a pressure at which the liquid (18) is sprayed from the jet nozzles (16; 16.1, 16.2, 16.3) is settable or set in dependence on the signals of the scale detection unit (32).
17. Method according to any one of claims 14 to 16, characterised in that a spacing (A) of the rotor head (14) from the surface (20) of the workpiece (12) is adjusted, namely in dependence on the signals of the scale detection device (32).
18. Method according to any one of claims 10 to 17, characterised by a rotor head pair (29) or a rotor module pair (31) in which at least one rotor head (14) is arranged respectively above and below the moved workpiece (12), wherein the pressure at which a liquid (18) is issued onto the workpiece (12) by the jet nozzles (16; 16.1, 16.2, 16.3) of the rotor head arranged below the workpiece (12) is greater than in the case of the jet nozzles (16; 16.1, 16.2, 16.3) of the rotor head arranged above the workpiece (12).

Images