EP3429770A1

EP3429770A1 - Device and method for descaling a workpiece in motion

Info

Publication number: EP3429770A1
Application number: EP17710888.3A
Authority: EP
Inventors: Angela ANTE; Jan Schröder; Jens MARBURGER; Wolfgang Fuchs; Michael Jarchau
Original assignee: SMS Group GmbH
Current assignee: SMS Group GmbH
Priority date: 2016-03-18
Filing date: 2017-03-14
Publication date: 2019-01-23
Anticipated expiration: 2037-03-14
Also published as: JP2019508257A; CN108778544A; KR102141440B1; CN108778543A; EP3429771A1; EP3429770B1; KR102166086B1; CN108883452B; KR20180117139A; JP2019511366A; RU2701586C1; CN108778543B; JP6770088B2; RU2699426C1; US11103907B2; EP3429773A1; RU2697746C1; KR20180117157A; EP3429771B1; EP3429773B1

Abstract

The invention relates to a device and a method for descaling a workpiece that is in motion relative to the device in a movement direction (X). The device (10) comprises a rotor head (14) which can rotate about an axis of rotation (R) that is tilted, at an angle (γ), at an incline with respect to an orthogonal line to a surface (20) of the workpiece (12). The device also comprises a plurality of jet nozzles (16) mounted on the rotor head (14), wherein a liquid (18), particularly water, can be emitted from the jet nozzles (16) onto the workpiece (12) at an angle of incidence (α) at an incline to the surface (20) of said workpiece (12). The jet nozzles (16) are mounted rigidly on the rotor head (14) such that, when said rotor head (14) rotates about its axis of rotation (R), the spray direction (S) of the liquid (18) emitted from the jet nozzles (16) is directed counter relative to a projection into a plane parallel to the surface (20) of the workpiece (12), i.e. at a spray angle (ß) of approximately 180° to the movement direction (X) of the workpiece (12).

Description

Apparatus and method for descaling a moving workpiece

The invention relates to an apparatus and a method for descaling a workpiece, which is moved relative to the device in a direction of movement. The workpiece is in particular a hot rolling stock.

According to the prior art, it is known for descaling workpieces, in particular hot rolling, to spray water onto the surfaces of the workpiece at high pressure. For a complete descaling of the surfaces of the workpiece, the high pressure spray is usually ejected from several nozzles of a scale washer. In this context, the scale scrubber used in a hot rolling mill is an assembly intended to remove scale, ie. H. of impurities of iron oxide, provided by the surface of the rolling stock.

WO 2005/082555 A1 discloses a scale scrubber with which a rolling stock, which is moved relative to the scale scrubber, is descaled by irradiation with high-pressure spray water. This scale scrubber comprises at least one nozzle surface row sweeping over the width of the rolling stock with a plurality of nozzle heads, wherein each nozzle head is rotationally driven by a motor about an axis of rotation perpendicular to the rolling surface. Furthermore, at least two eccentrically arranged with respect to the axis of rotation nozzles are provided with each nozzle head, which are arranged as close as possible structurally, on the circumference of the nozzle head. Such a scale scrubber is subject to the disadvantage that an energy input over the width of the rolling stock may have inhomogeneities, so that it comes to permanent temperature strip on the rolling stock, in the overlap region of adjacent nozzle heads. Furthermore, the nozzles are arranged on the respective nozzle heads inclined by an angle of attack to the outside, which is illustrated in FIG. 13. This causes the direction of injection of these nozzles at a Rotation of the nozzle heads is aligned about its axis of rotation in the direction of the feed of the rolling stock. Such an orientation of the ejected from the nozzle high-pressure spray is disadvantageous because in this case the jet of spray water is ineffective and therefore does not contribute to descaling the surface of the rolling stock.

WO 1997/27955 A1 discloses a process for descaling rolling stock, 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 small cooling of the rolling stock and to generate high jet pressures at low operating fluid pressure of the liquid jet is intermittent, d. H. temporarily suspended. Due to the one or more interruption of the liquid jet pressure peaks, which act as a jet pressure increase, whereby an improvement in the Entzunderungswirkung for the rolling stock is achieved. However, a control disc provided for this purpose, which is provided in fluid communication with a pressure medium supply line, disadvantageously increases the design complexity for this descaling technique. Furthermore, there is the risk of increased material stress, in particular due to cavitation, when forming the pressure peaks.

From 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 a direction of movement. For this purpose, a plurality of jet nozzles are provided on a rotating rotor head in the form of a nozzle holder, wherein liquid is discharged or sprayed under high pressure from the jet nozzles on a surface of the rolling stock, that while the emission direction, with which the liquid is ejected from the jet nozzles, always runs at an angle oblique to the direction of movement of the rolling stock. This oblique orientation of the emission direction ensures that removed scale from the surface of the rolling stock to the side is transported away from the rolling stock away. However, this is accompanied by a disadvantageous heavy pollution of the plant or its surrounding area.

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

This object is achieved by a device having the features defined in claim 1, and by a method having 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 relative to the device in a moving direction moving workpiece, preferably a hot rolling, and comprises at least one rotatable about a rotation axis rotor head on which a plurality of jet nozzles are mounted, wherein from the jet nozzles, a liquid, in particular water, can be applied to the workpiece in an angle of attack obliquely to the surface of the workpiece. Here, the jet nozzles are mounted on the rotor head, that upon rotation of the rotor head about its axis of rotation, the injection direction of the liquid ejected from the jet nozzles, based on a projection in a plane parallel to the surface of the workpiece, permanently opposite, ie in a spray angle between 170 ° and 190 °, preferably in a spray angle of 180 °, is aligned to the direction of movement of the workpiece and while the angle of attack for all jet nozzles remains constant. 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, such that both the liquid discharged from the jet nozzles after rebounding from the surface of the workpiece and the scale removed by the liquid from the surface of the workpiece purposefully be introduced into this catcher. In the same way, the invention also provides a method for descaling a workpiece, preferably a hot rolling stock. Here, the workpiece is moved relative to a device in a direction of movement, said device having at least one rotatable about a rotation axis rotor head on which a plurality of jet nozzles are mounted. While the rotor head is rotated about its axis of rotation, a liquid, in particular water, is ejected from the jet nozzles onto the workpiece at an angle of attack oblique to the surface of the workpiece. When the rotor head is rotated about its axis of rotation, the spraying direction of the liquid ejected from the jet nozzles is permanently opposite, relative to a projection in a plane parallel to the surface of the workpiece, ie at a spraying angle between 170 ° and 190 °, in particular at a spraying angle of 180 ° °, aligned with the movement direction of the workpiece, whereby the angle of attack remains constant for all jet nozzles. Furthermore, both the liquid ejected from the jet nozzles, after a rebound from the surface of the workpiece, and the scale removed by means of the liquid from the surface of the workpiece, are purposefully introduced into a collecting device.

The invention is based on the essential finding that it is possible 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 on the rotor head to align the liquid ejected from the jet nozzles permanently and preferably exactly opposite to the direction of movement of the workpiece, namely based on or in a projection of the injection direction of this liquid in a plane parallel to the surface of the workpiece. As a result, scale is always removed from the surface of the workpiece by the liquid opposite to the direction of movement of the workpiece, which contributes to a high efficiency of descaling. In this regard, it should be pointed out that effective descaling presupposes that the jet nozzles work, which means that the spray direction of the jet nozzles is aligned opposite to the direction of movement of the workpiece. The targeted introduction of the removed scale and the bounced off of the surface of the workpiece liquid in the catcher is effectively avoided that removed scale remains on the surface of the workpiece and is re-rolled in a renewed rolling in the surface. In the same way, this achieves the result that plant components of the device according to the invention are less or at best not at all polluted by removed scale and / or aimlessly spraying liquid. In addition, it should be noted that the fixed attachment of the jet nozzles on the rotor head leads to a significant structural simplification of the kinematics of the rotor head, because this planetary gear or the like, which are otherwise provided in the prior art for an additional rotation of the jet nozzles about its longitudinal axis, can be omitted.

In an advantageous embodiment of the invention, the rotor head relative to the collecting device is arranged such that the liquid from the jet nozzles, based on a projection in a plane parallel to the surface of the workpiece, is ejected exclusively in the direction of the catcher. In this way, a targeted introduction of removed scale and liquid, which bounces after the ejection from the jet nozzles of the surface of the workpiece, further optimized into the collecting device. In an advantageous embodiment 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, selected on the rotor head and such that the injection direction of at least one jet nozzle, preferably all jet nozzles, in which the liquid the workpiece is injected, permanently and opposite to the direction of movement of the workpiece runs, namely based on a projection of this injection direction in a plane parallel to the surface of the workpiece. As a result, the spray angle between the injection direction and the movement direction of the workpiece, in a plane parallel to the surface of the workpiece, is in a range between 170 ° and 190 °, and preferably takes the value of 180 °. This leads, in the same way as the just-mentioned arrangement of the rotor head relative to the collecting device, advantageously to a targeted introduction of the removed scale and bounced from the surface of the workpiece liquid into the catcher, because the injection direction of the jet nozzles no component or no share contains, which is directed towards a side edge of the workpiece.

Optimum energy input is achieved for the high-pressure sprayed onto the surface of the workpiece liquid in that a plurality of jet nozzles are mounted on the rotor head in each case a different radial distance from the axis of rotation, wherein from a jet nozzle having a greater radial distance to Has rotational axis, then a larger volume flow of liquid is applied as compared to a jet nozzle having a smaller radial distance from the axis of rotation. This can be achieved in a simple manner by selecting a suitable nozzle type, so that from a jet nozzle, which is arranged radially further away from the axis of rotation of the rotor head, correspondingly a larger amount of liquid, i. a larger volume flow is injected. By such a configuration of a plurality of jet nozzles on the rotor head, therefore, the energy input for the liquid transversely to the direction of movement of the workpiece, d. H. over its width, optimized.

In an advantageous embodiment of the invention, the rotor head is arranged inclined so that its axis of rotation is inclined with respect to an orthogonal to the surface of the workpiece obliquely at an angle. In this case, the jet nozzles are each firmly attached to the rotor head, so that the angle of attack, the ejected from the jet nozzles liquid with an orthogonal includes the surface of the workpiece, remains constant. Preferably, the jet nozzles are mounted on the rotor head such that their longitudinal axes are parallel to the axis of rotation of the rotor head. In an advantageous development of the invention, a first rotor head arrangement and a second 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 a rotor head arrangement, the present invention is either a rotor head pair in which a rotor head is respectively provided above and below a workpiece, ie, at its top and bottom, or a rotor module pair, in which - above and below the workpiece - each a plurality of rotor heads are juxtaposed and transversely to the direction of movement of the workpiece summarized. In a normal operation can be provided that liquid is ejected only from the jet nozzles of the first rotor head assembly on the workpiece. In a special operation, the jet nozzles of the second jet nozzle arrangement can then be switched on so that liquid is also ejected or sprayed onto the workpiece from the jet nozzles of this second jet nozzle arrangement. For this case, the blasting nozzles of both the first rotor head arrangement and the second rotor head arrangement are then used for descaling the workpiece. The jet nozzle arrangement of the second arrangement may be structurally different from the first rotor head arrangement. The use of both arrangements in special operation is recommended z. B. for hard to descaling steel grades, or stubborn tinder residues, which may arise, for example, by resting on oven rolls. In such an embodiment, according to which only the jet nozzles of the first rotor head arrangement are used in normal operation, the consumption of the operating medium can advantageously be minimized. This applies in the same way for the case that a plurality of rotor heads - as explained - combined to form a rotor head module are. In this case, only one pair of rotor modules is then in use during normal operation, wherein a further jet nozzle arrangement, which is arranged downstream in the direction of movement of the workpiece, is switched on as required. Further advantages of the invention are 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 adjusted transversely to the direction of movement to the width of the workpiece. In an advantageous embodiment of the invention may be provided with a control device signal technically connected scale detection device, which is arranged with respect to the direction of movement of the workpiece downstream of the rotor head and close to it, so as to be able to detect remaining scale on the surface of the workpiece. Based on the signals of this scale detection means, the descaling quality of the workpiece is compared by means of the control means with a predetermined target value and then suitably controlled or regulated in accordance therewith a high pressure pump unit in fluid communication with the jet nozzles of the rotor head.

The control of the high-pressure pump unit can be effected in such a way that a pressure with which liquid is ejected from the jet nozzles onto the surface of the workpiece is set as a function of the signals of the scale detection device. This means that the pressure for the liquid to be sprayed out is set just so high that a sufficient descaling quality for the workpiece is still achieved. If - as seen in the direction of movement of the workpiece - at least two jet nozzle arrangements are arranged one behind the other, can be achieved by the said control that a switchable jet nozzle arrangement is switched depending on the signals of the scale detection device suitably, what said special operation according to the invention equivalent. Compared to a conventional double-row arrangement of rotor heads or of spray bars, such a single-row arrangement, ie a single rotor head arrangement used in normal operation, achieves a substantial saving in operating media.

By the above adjustment of the pressure, d. H. By reducing the pressure, a reduced abrasion effect of the liquid on all surrounding materials or parts of the system also arises, as a result of which both the maintenance costs decrease and wear of the jet nozzles itself is reduced.

By installing a scale detection device and its integration into a control or regulating device, the amount of water required for a clean descaling of the workpiece can be suitably minimized by varying the pressure and / or the volume flow. This leads to a saving of energy for the provision of high-pressure water, as well as in the same way to a reduced cooling of the workpiece as a result of a reduced amount of liquid which is ejected onto the workpiece. In addition, it may be pointed out that a distance of the rotor head from the surface of the workpiece can be adjusted. Thus, an adaptation to different batches of workpieces with different heights is possible. 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 of the scale detection device. For example, it may be provided in this manner that, if the degree of descaling is insufficient, the distance between the rotor head and the surface of the workpiece is reduced, so that a greater impact pressure with respect to the liquid sprayed onto it is thereby established on the surface of the workpiece. 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 specification, at least can be slightly increased.

Further advantages of the invention are that it is possible by collecting the dissolved from the surface of the workpiece Zunders to reduce scale error by rolling uncontrollably falling tinder residues or even excluded. Accordingly, scale-free, clean surfaces with comparatively low water consumption are achieved for a workpiece, which saves considerable 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 catcher has a greater degree of contamination due to a higher solids content of detached scale particles. The reduced specific amount of water used for descaling the workpiece can significantly reduce the required heating energy for an oven or the requisite forming energy for subsequent rolling of the workpiece. Due to the temperature saving thus thinner end thicknesses can be produced for a workpiece or a hot rolling, so that the product mix can be increased. In addition, at a lower furnace temperature, the life of furnace rolls also increases significantly.

Embodiments of the invention are described in detail with reference to a schematically simplified drawing.

Show it:

1 is a simplified principle side view of a device according to the invention,

2 is a side view of a rotor head of the device of Fig. 1, Fig. 3a,

Fig. 3b and 3c each show a basic relationship between an injection direction of jet nozzles of a device according to FIG. 1 and a direction of movement in which a workpiece is moved past this device, FIG.

4 shows a simplified basic plan view of a device according to the invention according to a further embodiment,

5 is a simplified cross-sectional view of a catcher of the apparatus of FIG. 4;

6 shows a simplified side view of a rotor head pair, in which rotor heads according to FIG. 2 are respectively arranged on an upper side and on an underside of a workpiece to be descaled

7 is a simplified front view of a rotor module in which a plurality of rotor heads are arranged side by side and transversely to the direction of movement of the workpiece,

8 shows 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 respectively injection patterns which form on the surface of the workpiece with a liquid ejected onto a workpiece, FIG.

10 is a flowchart according to which the invention is used in practice, and

Fig. 1 1, 12 are each side views of a rotor head according to further embodiments of the invention.

Hereinafter, various embodiments of the invention will be described in detail with reference to Figs. In the figures, the same technical features are designated by the same reference numerals. It should also be noted that the illustrations in the drawing are simplified in principle and shown in particular without scale. In some figures Cartesian coordinate systems are registered for the purpose of a 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 relative to the device 10 in a movement direction X. The workpiece 12 may be hot rolled stock that is moved past the apparatus 10.

In the embodiment of Fig. 1, the device 10 comprises a rotor head 14 which can be rotated about a rotation axis R. A rotation of the rotor head 14 about its axis of rotation R by means of motor means (not shown), for example by an electric motor. On a front side of the rotor head 14, which faces the workpiece 12, jet nozzles 16 are mounted. From the jet nozzles 16, a liquid 18 (symbolized in simplified dashed lines in FIG. 1) is injected under high pressure onto a surface 20 of the workpiece 12 in order to descalate the workpiece appropriately. To this end, the jet nozzles 16 are in fluid communication with a high-pressure pump unit (not shown) by means of which the jet nozzles are supplied with a liquid under high pressure. The liquid 18 is preferably water, without limitation to water only.

In the embodiment of FIG. 1, the device 10 comprises a catching device 22, which is arranged upstream of the rotor head 14 with respect to the movement direction X of the workpiece 12. Such catcher 22 is for the purpose of accommodating both scale removed from the surface 20 of the workpiece by the high pressure liquid and liquid bouncing therefrom upon contact with the surface 20 of the workpiece 12. In the illustration of FIG. 1, removed scale and the liquid bounced off the surface 20 of the workpiece 10 are symbolized in a simplified manner by dotted lines. In conjunction 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 adjacent to an open area of the collecting device 22. The lower baffle 23.1 is attached or attached to the collecting device 22 in such a way that its free end is positioned directly above the workpiece 12 and at an angle δ (FIG. 1) between 25-35 ° with the surface 20 of the workpiece includes. Preferably, the lower baffle 23.1 is mounted such that the angle δ to the surface 20 of the workpiece 12 assumes a value of 30 °.

The lower baffle 23.1 is arranged in accordance with the angle δ of preferably 30 ° rising flat in the direction of the collecting device 22. Thus, the lower baffle 23.1 fulfills the task of a baffle and causes a targeted entry of the scale and bounced from the surface 20 liquid into the catcher 22nd

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 assumes the function of a lid. The distance of an edge of the upper cover plate 23.2, which is adjacent to the rotor head 14, is selected such that the portion between the edge of the upper cover plate 23.2 and the rotor head 14 with respect to scale particles is passage-free. For the purposes of the present invention, "pass-through-free" means that scale particles, if they are detached from the surface 20 of the workpiece 12 as a result of the sprayed-out water, can not 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 shroud 23.2 prevents scale or bounced liquid from the surface 20 of the workpiece 12 from escaping upwards to the surroundings, although this ensures that air flows through the section between the upper shroud 23.2 and the rotor head 14 can pass through, so that forms no back pressure during operation of the device 10 according to the invention below the upper cover plate 23.2.

Below, with reference to FIGS. 2 and 3 further relationships for the arrangement of the rotor head 14 and the attached thereto jet nozzles 16 are explained.

The jet nozzles 16 are fixedly attached to a workpiece 12 opposite end face of the rotor head 14. Here, the longitudinal axes L of the jet nozzles 16 are aligned parallel to the axis of rotation R of the rotor head 14. Accordingly, the injection direction S (see Fig. 2), in which the liquid is ejected from the jet nozzles 16, parallel to the axis of rotation R of the rotor head 14. The rotation axis R is with respect to an orthogonal to the surface 20 of the workpiece 12 obliquely in one Angle γ (Fig. 2) arranged inclined. By 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, an angle of attack α results (see FIG. 2) with which the liquid 18 injected from the jet nozzles 16 flows on the rotor Surface 20 of the workpiece hits. This angle 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 α in the embodiment of Fig. 2 is the same the inclination angle γ of the rotation axis R.

The rotor head 14 is designed to be height adjustable. This means that a distance A, which has an intersection of the rotation axis R with the end face of the rotor head 14 to the surface 20 of the workpiece 12 (FIG. 2), can be changed if necessary. For the purposes of the present invention, this distance A is to be understood as a spray distance. In a reduction of this Distance A, the resulting impact pressure of the liquid 18 on the surface 20 of the workpiece 12 to. The height adjustability for the rotor head 14 is simply symbolized by the arrow "H" in Fig. 2, and can be realized by a height-adjustable support to which the rotor head 14 is attached. Details of an adjustment of this distance A will be described in detail below explained.

FIG. 3 illustrates a relationship between the injection direction S, with which the liquid 18 is sprayed from the jet nozzles 16, and the movement direction X, with which the workpiece 12 is moved past the device 10 or its rotor head 14. 3 shows a projection of the injection direction S in a plane parallel to the surface 20 of the workpiece 12. In the example of FIG. 3a, the injection 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, d. H. aligned in a spray angle ß of exactly 180 ° to the direction of movement X. As a result, the spray direction S of the liquid 18, when permanently sprayed onto the workpiece 12 under high pressure, does not have a component pointing in the direction of a lateral edge of the workpiece 12. This ensures that the liquid 18 is always injected exactly 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 is then introduced into the collecting device 22 in a targeted manner in conjunction with the liquid 18 bounced off the surface 20 of the workpiece 12.

According to the examples of Fig. 3b and Fig. 3c, it is also possible that the spray angle ß 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 then the injection direction S is not exactly opposite to the direction of movement X, but with the direction of movement X encloses an angle, which - as explained and in Figs. 3b and 3c illustrated - may be in a range between 170 ° to 190 °.

At this point it should be noted separately that the orientation of the injection direction S explained above, as shown in FIGS. 3 a, 3b and 3c, remains unchanged or constant during rotation of the rotor head 14 about its axis of rotation R. The same applies to the angle of attack a. With regard to the rotor head 14 according to FIG. 2, it is pointed out that this rotor head 14 can correspond to that of FIG. In a departure from this, it is also possible for the present invention to provide the rotor head 14 according to FIG. 2 without a collecting device 22. A further embodiment for a device 10 according to the invention is shown in FIG. 4, namely in a basically greatly simplified plan view. Here are two rotor heads 14.1 and 14.2, with respect to the direction of movement X of the workpiece 12, arranged one behind the other. Each of these rotor heads 14.1 and 14.2 is associated with its own collecting device 22, which is arranged in each case, with respect to the direction of movement X of the workpiece 12, upstream of an associated rotor head. In principle, another type of jet nozzle can be provided instead of the rotor head 14.2.

The plan view of Fig. 4 illustrates once again that the injection direction S, with which the liquid 18 is discharged from the attached to a rotor head 14 jet nozzles 16, has no share, which points in the direction of a lateral edge 13 of the workpiece 12, but instead directed directly to an associated catcher 22. Due to the inventively reduced applied amount of water at the same time improved effectiveness of the degree of contamination of the water increased with scale residues or corresponding solid particles, so that recommends another embodiment of the catcher.

The entry of removed scale and liquid, which bounces off a contact with the workpiece 12 from its surface 20, into a respective catcher 22 is as explained above supported by the flat at the angle δ rising lower baffle 23.1, and is in the Fig. 4 symbolically symbolized by the arrows "E". Further details of the catcher 22 will become apparent from Fig. 5, which shows a cross-sectional view thereof.

A bottom surface 25 of the catcher 22 is formed laterally inclined downwards. In the illustration of 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 catcher 22, starting from its center, then drops to the lateral edges 24, thereby also moving scale and liquid introduced into the catcher 22 in the direction of the lateral edges 24.

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

The discharge of cleaning liquid and scale out of the collecting device 22, namely through the discharge pipe 26, can be optimized by means of a conveying device 27 by means of the cleaning liquid and scale within the collecting device in the direction of an opening of the discharge pipe 26 or in the direction of the lateral edges 24 become. For this purpose, the Conveying device 27, for example 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, eg scraping elements, conveying screws or the like, by means of which the liquid and / or the scale are specifically conveyed in the direction of an opening of the outlet pipe 26.

Hereinafter, with reference to Figs. 6 and 7, there are shown and explained possible arrangements of rotor heads, e.g. in the embodiment of Fig. 4 can be used.

FIG. 6 shows a side view of a rotor head pair 29, in which a rotor head 14 is provided respectively above and below the workpiece 12, ie both at the top side and at the bottom side thereof. It can be seen that the rotor head 14, which is arranged below the workpiece 12, is positioned with respect to the movement direction X of the workpiece 12 downstream of the rotor head 14, which is arranged above the workpiece 12. This is why, for example, liquid 18, which is sprayed from the jet nozzles 16 of the workpiece 12 disposed below the rotor head 14, does not bounce against the above the workpiece 12 disposed rotor head 14, if no workpiece or strip material should be located between these two rotor heads. The offset shown in Fig. 6 between the above and below the workpiece 12 arranged rotor heads does not change the fact that these two rotor heads, in the context of the present invention, are to be understood as a rotor head pair 29. In this regard, it is understood that reference numerals 14.1 and 14.2 shown in FIG. 4 may each be such a rotor head pair. 7 shows a front view of rotor head modules 30, which are respectively provided above and below the workpiece 12 and thereby form a rotor module. Pair 31 form. In detail, the respective rotor head modules 30 are made up of a plurality of rotor heads 14 arranged side by side and transverse to the movement direction X of the workpiece. Notwithstanding the representation in FIG. 7, fewer or more than three rotor heads 14 can also be combined to form a rotor module 30.

For the illustration of FIG. 6, it is additionally pointed out that this can also be a side view of a rotor module pair 31 according to FIG. 7, with only the rotor head 14 lying in the paper plane at the top and bottom of the rotor head Workpiece is visible.

With regard to the embodiments according to FIGS. 6 and 7, it should be noted 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. As a result, a supply of attached to the rotor heads jet nozzles 16 is ensured with high-pressure water.

In the embodiment according to FIG. 4, deviating from the illustration shown, it may also be provided that rotor modules 30 are provided instead of the individual rotor heads 14.1 and 14.2, which are arranged one behind the other in relation to the movement direction X, namely because of the arrangement above and below of 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. 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 substantially corresponds to a width of the workpiece 12. This leads to the advantage that, in contrast to eg only a single rotor head, the diameter of the width of the Workpiece 12 corresponds, then the diameter of the individual rotor heads of a rotor module 3 may each be smaller, associated with the advantage that then higher rotational speeds are adjustable for these rotor heads, possibly also to adapt to high rolling speeds and high feed rates 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 to the width of the workpiece is adjusted.

8 symbolizes an attachment of a plurality of jet nozzles 16 on an 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 which each have a different distance s from the axis of rotation R of the rotor head 14. In the illustration of Fig. 8, the axis of rotation R is perpendicular to the plane of the drawing.

The different distances of the respective jet nozzles 16.1, 16.2 and 16.3 are denoted by Si, S2 and S3 in FIG. 8, with the proviso that Si>S2> S3. In such an arrangement of jet nozzles, each having a different radial distance from the axis of rotation R, it is provided that a larger volume flow of liquid is ejected from a jet nozzle, which has a greater radial distance from the axis of rotation R, than a jet nozzle which has a smaller spacing to the axis of rotation. With respect to the three nozzles 16.1, 16.2 and 16.3 according to FIG. 8, the relationship: Vi> V ₂ > V ₃ applies to the volume flow discharged from these nozzles. As a result, a uniform energy input on the surface 20 of the workpiece 12 transversely to its direction of movement X is achieved for the liquid ejected from the jet nozzles 16.1, 16.2 and 16.3. The relationships just explained in relation to the illustration of FIG. 8 also apply to a number of jet nozzles of greater or smaller three, namely at least for a plurality of jet nozzles, each having a different distance from the axis of rotation R of the rotor head 14. It should also be noted that the example of FIG. 8 also applies to all rotor heads 14 which are shown and explained in FIGS. 1-7.

For the invention, a scale detection device 32 may be provided which is disposed downstream of a rotor head 14 and a rotor head pair 29 and a rotor module pair, respectively, with respect to the movement direction X of the workpiece 12, with reference only to a rotor head 14 for the sake of simplicity without limitation. In the embodiment of FIG. 4, such a scale detection device 32 is disposed downstream of the rotor head 14.2. Regardless of the number of rotor heads, which in the present invention may be arranged one behind the other with respect to the movement direction X of the workpiece 12, it is important for the scale detection device 32 to be located in close proximity to and downstream of a rotor head (eg rotor head 14.2 according to FIG 4) of the device 10 is arranged, at least before the workpiece 12 z. B. is subjected to a re-rolling. The scale detection device 32 is signal-wise connected to a control device 34 (FIGS. 1, 4). By means of the scale detection device 32, it is possible to reliably detect or detect any remaining residual 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, ie at the top and at the bottom thereof. Accordingly, it is possible by means of the scale detection device 32 to detect possible residual scale on both surfaces of the workpiece 12. In the representations of FIGS. 1 and 4, it is symbolically shown that a rotor head 14 is likewise connected to the control device 34 in terms of signaling. This means that it is possible by means of the control device 34 to change the pressure with which the liquid sprayed from the jet nozzles 16 impinges on a surface 20 of the workpiece 20 in a suitable manner. Such a change in the impact pressure of the liquid can be done for example by connecting or disconnecting a pump of the high-pressure pump unit, with which the pressurized water line D is connected to the jet nozzles 16. Additionally or alternatively, it can be provided that the high-pressure pump unit, with which the pressure supply for the jet nozzles 16 is ensured, 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 irrespective of the provision of a scale detection device 32, it is possible for the present invention for a rotor head 14 to be signaled to the control device 34. Accordingly, by means of the control device 34, for example, the speed at which the rotor head 14 is rotated about its axis of rotation R, to be adjusted, for example, in dependence on the feed rate at which the workpiece in its direction of movement X is moved past the device 10. By means of such an adaptation of the rotational speed for the rotor head 14, in particular to the feed rate of the workpiece 12 in its direction of movement X, an optimum 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 optimum adaptation of the Speed of the rotor head 14 to the feed rate of the workpiece 12 is shown in the spray pattern of FIG. 9a, which shows a section of a surface 20 of the workpiece 12 in a plan view. In contrast, the illustration of Fig. 9b illustrates a non-optimal adjustment of the rotational speed of the rotor head 14 to the feed rate of the workpiece 12. By means of the invention, it is possible to avoid a spray pattern as shown in Fig. 9b. The invention now works as follows:

For descaling desirably the surfaces 20 of a workpiece 12, this workpiece is moved relative to the inventive apparatus 10 in a direction of movement X. In this case, rotor heads 14 of the device 10 are preferably provided both on an upper side and on an underside of the workpiece 12, as shown in the embodiment of FIG. 6. Descaling of the workpiece 12 is achieved by a liquid 18 being attached to a rotor head 14 Jet nozzles 16 is sprayed under high pressure on the surfaces 20 of the workpiece 12. 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 rebounding from the surface 20 of the workpiece 12 liquid targeted introduced into the catcher 22.

Means (not shown) are provided by which the control device 34 receives information regarding the feed rate 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 rate of the workpiece 12. Such an adaptation is also possible during ongoing production operation, if fluctuations in the feed rate for the workpiece 12 occur , The control device 34 may be set up by programming such that such an adaptation of the rotational speed of a rotor head 14 is also regulated.

Based on the signals of the scale detection device 32, the pressure at which the jet nozzles 16 attached to a rotor head 14 are supplied with the liquid 18 can be adjusted to a predetermined value. This means that, for example, the pressure of the liquid 18 provided for the jet nozzles 16 is just set so high that a sufficient degree of descaling is achieved, which is then achieved by means of the Scale detection device 32 can be monitored. As a result, a saving of water and energy is possible. If, on the other hand, it should be recognized by the control device 34, on the basis of the signals generated by the scale detection device 32, that the descaling quality falls below a certain desired value, this can be achieved by a suitable pressure increase, by switching on a pump and / or by connecting an additional descaling unit in the form of a rotor head pair 29 or a rotor module pair 31 are compensated. Such an operation according to the present invention is also illustrated in the flowchart of FIG. 11.

Additionally and / or alternatively, the change of the impact pressure can be effected by a height adjustment of the rotor head arrangement. 2, as already explained, is symbolized by the arrow "H." In this case, the distance A (FIG. 2), which a rotor head 14 has from the surface 20 of the workpiece 12, can depend on the signal values For example, this distance A may be reduced if the descaling quality of the surface 20 of the workpiece 12 is judged unsatisfactory, as a result of the reduced distance A, the impact pressure of the liquid 18 on the surface 20 of the workpiece Conversely, this means that, at any rate, as long as the quality of descaling remains sufficiently high and a predetermined set point is reached, the distance A can also be increased of the rotor head (see angle γ in Fig. 2) and the attachment of the jet nozzles 16 to the rotor head to be selected such that the angle of attack α is in a range of 5 ° to 25 °, and preferably assumes a value of 15 °. Finally, it should be pointed out that a rotor head 14.3 according to the representation of FIG. 11 and / or a rotor head 14.4 as shown in FIG. 12 can also be used for the present invention. In the case of 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 an end face of the rotor head 14.3. Upon rotation of the rotor head 14.3 about its axis of rotation R, the jet nozzles 16 are simultaneously and synchronously rotated around their longitudinal axis L such that the angle of attack α with respect to the surface 20 remains constant in each case. This is achieved via a planetary gear 36, which is integrated in the rotor head 14.3.

In the case of 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 mounted with their longitudinal axis L parallel to the axis of rotation R on the rotor head 14.4. The jet nozzles 16 have at their respective nozzle mouth 17 a suitably formed outlet opening, through which a deflection of the ejected liquid 18 is achieved, whereby the angle of attack α shown in FIG. 13 results. This angle of attack α remains constant during a rotation of the rotor head 14.4 about its axis of rotation by the jet nozzles 16 are rotated by a planetary gear synchronously with the rotation of the rotor head 14.4 each about its longitudinal axis L. It is understood that the rotor heads 14.3 and 14.4. can also be used in the manner of a rotor head pair 29 and / or in the manner of a rotor module pair 31, as shown in Fig. 6 and in Fig. 7.

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

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

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

LIST OF REFERENCE NUMBERS

10 device

12 workpiece

14 rotor head

16 steel nozzle

16.1 steel nozzle

16.2 Steel nozzle

16.3 Steel nozzle

18 fluid

20 surface

22 catch direction

23.1 Covering device

23.2 Covering device

26 drain pipe

27 conveyor

28 rinse nozzle

29 rotor head pair

31 rotor module pair

32 Zundedetektionseinrichtung α angle of attack

ß spray angle

γ angle

L longitudinal axis

R rotation axis

S injection direction

Vi volume flow

V ₂ volumetric flow

V ₃ volumetric flow

X direction of movement

Claims

claims

1 . Device (10) for descaling a workpiece (12) moving relative to the device (10) in a direction of movement (X), preferably a hot rolling stock

at least one rotor head (14) rotatable about an axis of rotation (R), to which a plurality of jet nozzles (16) are attached, wherein a liquid (18), in particular water, from the jet nozzles (16) is applied to the workpiece (12) at an angle of attack (Fig. a) obliquely with respect to an orthogonal on a surface (20) of the workpiece (12) can be discharged, characterized

in that the jet nozzles (16) are mounted on the rotor head (14) such that upon rotation of the rotor head (14) about its axis of rotation (R), the spraying direction (S) of the liquid (18) discharged from the jet nozzles (16) a projection in a plane parallel to the surface (20) of the workpiece (12), permanently opposite, ie in a spray angle (ß) between 170 ° and 190 °, preferably in a spray angle (ß) of 180 °, to the movement direction (X) of the workpiece (12) is aligned while the angle of attack (a) for all jet nozzles (16) constant stays the same, and

in that a collecting device (22) is provided, which is arranged upstream of the rotor head (14) with respect to the direction of movement (X) of the rolling stock, such that both the liquid (18) discharged from the jet nozzles (16) after rebounding from the surface (20) of the workpiece (12) and the by means of the liquid (18) from the surface (20) of the workpiece (12) removed scale in the collecting device (22) can be introduced. Device (10) according to claim 1, characterized in that the plurality of jet nozzles (16) on the rotor head (14) in a different radial distance (si; S2; S3) are mounted to its axis of rotation (R), wherein from a Jet nozzle (16.1, 16.2, 16.3), which has a greater radial distance from the axis of rotation (R), a larger volume flow (Vi, V ₂ , V ₃ ) can be discharged to liquid (18) than in comparison with a jet nozzle, which has a smaller volume radial distance to the axis of rotation (R) has.

Device (10) according to claim 1 or 2, characterized in that the rotor head (14) relative to the collecting device (22) is arranged such that the liquid (18) from the jet nozzles (16) exclusively in the direction of the collecting device (22) becomes.

Device (10) according to one of claims 1 to 3, characterized in that the positioning of the rotor head (14) relative to the direction of movement of the workpiece (12) and the attachment of at least one jet nozzle (16), preferably all jet nozzles (16) on the rotor head (14) are selected such that the injection direction (S) of at least one jet nozzle (16), preferably all jet nozzles (16), in which the liquid (18) is applied, when projecting in a plane parallel to the surface (20) of the workpiece (12) runs exactly opposite to the direction of movement (X) and thus the spray angle (β) between the injection direction (S) and the direction of movement (X) is exactly 180 °.

Device (10) according to one of claims 1 to 4, characterized in that the collecting device (22) is provided with at least one discharge pipe (26) through which the cleaning liquid and removed scale from the collecting device (22) can be discharged. Device (10) according to one of claims 1 to 5, characterized in that the collecting device (22) is equipped with a conveyor (27), by means of the removed scale within the collecting device (22) in the direction of an opening of the discharge pipe (26) transportable is, preferably, that the conveying device (27) has at least one rinsing nozzle (28), from which a fluid can be discharged.

Device (10) according to one of claims 1 to 6, characterized in that individual rotors of a rotor module can be switched off individually and / or in groups without pressure, for adapting the application of the liquid (18) transversely to the direction of movement (X) of the workpiece (16). ,

Device (10) according to one of claims 1 to 7, characterized in that between the collecting device (22) and the rotor head (14) a covering device (23.2) is arranged, extending from the collecting device (22) directly to the rotor head ( 14), such that a portion between the rotor head (14) and an edge of the cover device (23.2) is permeable with respect to scale particles.

Device (10) according to one of claims 1 to 8, characterized in that the rotor head (14) with its rotation axis (R) with respect to an orthogonal inclined on a surface (20) of the workpiece (12) at an angle (γ) , Wherein the jet nozzles (16) are each fixedly attached to the rotor head (14), preferably that the jet nozzles (16) are arranged with their longitudinal axes (L) parallel to the axis of rotation (R) of the rotor head (14).

Method for descaling a workpiece (12), preferably a hot rolling stock, in a direction of movement relative to a device (10) having at least one rotor head (14) rotatable about a rotation axis (R) and to which a plurality of jet nozzles (16) are attached X) moves is, with a liquid (18), in particular water, from the jet nozzles (16) while the rotor head (14) is rotated about its axis of rotation (R), on the workpiece (12) at an angle of attack (a) obliquely to the surface ( 20) of the workpiece (12) is deployed,

characterized,

in that upon rotation of the rotor head (14) about its axis of rotation (R) the spraying direction (S) of the liquid (18) discharged from the jet nozzles (16), relative to a projection in a plane parallel to the surface (20) of the workpiece (12) , permanently opposed, ie in a spray angle (β) between 170 ° and 190 °, and in particular in a spray angle (ß) of exactly 180 °, to the direction of movement (X) of the workpiece (12) is aligned and thereby the angle of attack (a) for all jet nozzles (16 ) remains constant, and

in that both the liquid (18) discharged from the jet nozzles (16) after rebounding from the surface (20) of the workpiece (12) and the scale removed by means of the liquid (18) from the surface (20) of the workpiece (12) purposefully be introduced into a collecting device (22).

1 . A method according to claim 10, characterized in that the rotational speed with which the at least one rotor head (14) is rotated about its axis of rotation (R) (R), by means of a control device (34) is adapted to the feed rate at which the workpiece ( 12) in the direction of movement (X) is moved, preferably, that the adjustment of the rotational speed of the rotor head (14) to the feed rate of the workpiece (12) is controlled.

2. The method of claim 10 or 1 1, characterized in that from a plurality of jet nozzles (16.1, 16.2, 16.3) on the rotor head (14) in each case in a different radial distance (si; S2, S3) to the latter Rotation axis (R) are attached, different sizes Volume flows to be sprayed liquid (18), wherein from a jet nozzle (16.1; 16.2; 16.3), which has a greater radial distance from the axis of rotation (R), a larger volume flow (i; V ₂ ; V ₃ ) of liquid (18) is injected as compared to a jet nozzle having a smaller radial distance from the axis of rotation (R).

Device (10) or method according to one of claims 1 to 12, characterized in that a first rotor head arrangement and a second jet nozzle arrangement are provided, wherein the rotor head arrangement each consist of a rotor head pair (29) or of a rotor module Pair (31) is formed and the first and second arrangement with respect to the movement direction (X) of the workpiece (12) are arranged one behind the other and in particular adjacent to each other, preferably that in a normal operation, liquid (18) only from the jet nozzles (16 ) of the first rotor head arrangement (14.1) is applied to the workpiece (12), wherein in a special operation, the jet nozzles (16) of the second jet nozzle arrangement (14.2) are switched or can be switched so that liquid (18) also from the jet nozzles (16) of the second jet nozzle arrangement (14.2) is applied to the workpiece (12) and, correspondingly, for descaling the workpiece (12) then both rotor head arrangements n (14.1, 14.2) are used.

Device (10) or method according to one of Claims 1 to 13, characterized in that a scale detection device (32) 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 signal-connected are provided, wherein with the scale detection device (32) remaining scale on the surface (20) of the workpiece (12) is detectable or detected, wherein the control device (34) is set up in a program-like manner, on the basis of the signals of the scale detection device (32) the descaling quality of the workpiece (12) is compared with a predetermined target specification and in dependence thereon a high-pressure pump unit which is in fluid communication with the jet nozzles (16) of the rotor head (14) is controlled, preferably regulated ,

15. Device (10) or method according to claim 14, if appended to claim 13, characterized in that the jet nozzles (16) of the switchable rotor head arrangement (14.2) are set in operation in response to the signals of the scale detection device (32), namely in the special mode.

16. Device (10) or method according to claim 14 or 15, characterized in that by means of a control of the high-pressure pump unit, a pressure with which the liquid (18) from the jet nozzles (16) is ejected, in dependence of the signals of the scale detection device (32) is adjustable or is set.

17. Device (10) or method according to one of claims 14 to 16, characterized in that a distance (A) of the rotor head to

Surface (20) of the workpiece (12) is adjustable or is adjusted, namely in response to the signals of the scale detection device (32).

18. Device (10) or method according to one of claims 1 to 17, characterized by a rotor head pair (29) or a rotor module pair

(31), wherein at least one rotor head (14) respectively above and below the moving workpiece (12) is arranged, wherein the pressure with which a liquid (18) on the workpiece (12) through the jet nozzles (16) of the below of the workpiece (12) arranged rotor head is larger than in the jet nozzles (16) of above the workpiece (12) arranged rotor head.