METHOD, REEL DEVICE AND COMPUTER PROGRAM FOR OPERATING THE REEL DEVICE

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a national stage application, filed under 35 U.S.C. § 371, of International Patent Application PCT/EP 2023/073877, filed on Aug. 31, 2023, which claims the benefit of German Patent Application DE 10 2022 210 533.8, filed on Oct. 5, 2022.

TECHNICAL FIELD

The disclosure relates to a method for operating a reel device, wherein the reel device has a reel mandrel for winding up a strip, preferably a metal strip. The reel mandrel has at least one, typically a plurality of segments distributed over the perimeter thereof, which are in each case joined, via at least two link plates, to a control rod that can be axially moved in the reel mandrel, for radially extending and retracting the segment into at least one operating position. The disclosure also relates to the reel device itself.

BACKGROUND

Reel devices are known and are subject to high mechanical loads in the everyday operation of a rolling mill. Accordingly, wear of the moving parts of the reel mandrel is unavoidable. A distinction must be made between wear conditions that are visible from the outside and wear conditions that are not visible from the outside. The Japanese patent application JP 2000-226141 A deals with wear that occurs on the outer side of the segments on which the strip/metal strip is wound up.

In contrast, there is currently no way of detecting wear on the link plates or the housing of the compression spring unit in the installed state of the reel mandrel. There are, however, soft indicators, such as a “rattling” of the segments during idle operation or indirect measurements using pressure rollers, which indicate wear of the aforementioned internal components of the reel mandrel. Regular maintenance of the reel mandrel is also typically carried out if the “wound tonnage” has exceeded a predefined weight threshold value. However, the specified methods do not allow for a precise determination of the optimal point in time of replacement for wear parts. In this respect, a service life that is optimized for wear of the reel mandrel is not possible. This results in unnecessary costs due to non-optimal lifetime utilization of the reel mandrel.

SUMMARY

The disclosure is based on the object of further developing a known method and computer program for operating a reel device along with a corresponding known reel device itself, in such a way that wear conditions of internal components of the reel mandrel that are not visible from the outside are also reliably identified, without the reel mandrel having to be disassembled into its components.

This object is achieved by a method that includes the following steps: b) Directly or indirectly determining and recording the radial distance of the segment in the operating position in relation to a stationary reference position at different points in time during the service life; c) Evaluating the distances recorded at the different points in time in terms of whether they exceed a predefined upper threshold value or fall below a predefined lower threshold value during the service life of the reel device; and d) Indirectly identifying a wear condition of the reel device if the measured radial distances exceed the upper threshold value or fall below the lower threshold value starting on one of the points in time.

If individual internal components of the reel mandrel are subject to wear during the service life thereof, this leads to the fact that different predetermined operating positions for the segments of the reel mandrel, which could still be approached at an initial point in time of use, can no longer be approached precisely at a later point of time of use after interim use and wear. In particular, the controlled operating positions at the later point in time of use no longer correspond to the operating positions as they were controlled at the first point in time of use, e.g. when the reel mandrel was in a like-new state. The difference in the controlled operating positions can be seen in the changing distances of the controlled operating positions in relation to stationary reference positions during the service life of the reel mandrel.

The present disclosure provides for determining the change in the controlled operating positions during the service life of the reel mandrel in order to be able to draw inferences about wear of internal components of the reel mandrel.

The term “determining . . . the radial distance . . . ” is to be interpreted broadly. “Determining” includes, in particular, measuring and/or simulating the radial distance.

In the phrase “directly or indirectly determining and recording the radial distance . . . ,” “directly determining” means the actual determination of the specific radial distance. In contrast, “indirectly determining” means the determination of a physical quantity representing the radial distance.

The term “determining and recording the radial distance of the segment . . . at different points in time during the service life” also includes a so-called “continuous-time” determination and recording of the distances with any small temporal resolution. Two of these points in time limit an observation period during the service life.

The term “stationary” is used here: The segment can be moved relative to the stationary reference position.

The term “indirectly identifying” refers to the fact that the wear conditions are not directly visible to an observer from the outside, because components inside the reel mandrel may be affected by wear. If the distances determined and recorded exceed or fall below their associated predetermined threshold values, this knowledge can be used to infer wear conditions.

In general: Whether the wear to be detected here leads to an enlargement or reduction in the observed distances depends on the position of the stationary reference position in relation to the segments. In this description, it is assumed in principle that the stationary reference position is radially further inside the reel mandrel than the segments. For example, the upper edge of a housing of the compression spring unit is selected as the stationary reference position. In principle, however, any other stationary position in space can be selected as the reference position; for example, stationary points in space that are radially further out than the segments can also be selected as the reference position. Then, the evaluation of the recorded distances must be reversed in terms of whether they exceed or fall below a threshold value during the service life thereof. This is what is meant by the phrase “or vice versa.”

In the present disclosure, it is assumed that the compression spring unit is not subject to wear.

The present disclosure provides for an at least temporary intelligent evaluation of the distances between the segments in an operating position in relation to a stationary reference position during the service life thereof, preferably starting with the new state / a comparable fault-free state after maintenance. The method for operating a reel device allows a precise statement to be made about the wear pattern of the main wear parts of the reel mandrel on the basis of these recorded distances. By carrying out the method for operating a reel device, the user of the reel mandrel can identify creeping wear, even of internal components of the reel mandrel, quite accurately and thus plan a targeted replacement or a targeted maintenance of the reel mandrel during an imminent shutdown of the reel mandrel, without having to take the system out of operation.

In accordance with a first exemplary embodiment, the first operating position is a pre-expanded wrapping position (winding start position) of the segment without a wrapped strip. If, when approaching the wrapping position, an increasing enlargement of the distance of the segment in the wrapping position in relation to the stationary reference position is detected during the service life of the reel device a wear condition in the form of an undesired elongation of the linking and/or a widening of joint bores in the link plates and/or wear on the fastening bolt by which the link plates are joined to the control rod are inferred. This applies in particular if the recorded distances exceed the predefined upper threshold value, or vice versa.

In accordance with a second alternative exemplary embodiment, the second operating position is a winding position of the segment in which at least one turn, preferably a plurality of turns, of the strip are already wound up onto the segment and the reel mandrel. If, for this operating position, an increasing reduction in the distance of the segment in relation to the stationary reference position located radially further inwards is detected during the service life of the reel device, the method for operating a reel device provides for the wear condition to be inferred in the form of undesired abrasion on the surface of the ramp on the outer side of the control rod and/or on the lower side of the housing of the compression spring unit. This applies in particular if the distances recorded during the service life fall below the predefined lower threshold value.

In principle, the terms “wrapping position” for the first operating position and “winding position” for the second operating position must be distinguished from one another. Within the meaning of the present disclosure, the wrapping position refers to a position in which the segments are slightly extended in the radial direction in relation to their collapsed position and in which a wrapping of the strip on the reel mandrel/on the segments of the reel mandrel begins. Wrapping means that initially only a few turns, but not the full length of the strip, are wound up onto the reel mandrel. When wrapping typically 1-7 coil turns of the strip onto the reel mandrel, the wrapped strip exerts a radial compression force on the compression spring unit of the reel mandrel due to the increasing strip tension, contrary to the spring compressive force of the compression spring unit acting radially outwards. As a result, the at least one segment is displaced to a compression position that is radially further inwards in relation to the wrapping position.

In order to have sufficient static friction between the segments and the innermost layer of the wound-up strip for a subsequent continuation of the winding-up process of the strip, the segment is then moved radially further outwards from the compression position into a winding position prior to the continuation of the winding-up process, in which the winding of the reel mandrel with the strip is continued. The winding position can coincide with the wrapping position in the radial direction; however, the winding position can also be radially further inwards or further outwards in relation to the wrapping position. This depends on the predefined force with which the segments are to be pressed against the turn of the strip to be wound.

In accordance with a third exemplary embodiment, the operating position is the discharge position of the segment on the reel mandrel. This means the following: The segment is retracted against the spring force of the compression spring unit to an outer diameter that is smaller than the diameter of the eye of a coil previously wound up onto the reel mandrel. In this discharge position, it is therefore possible to discharge a previously wound-up coil from the reel mandrel. However, the outer diameter of the segments in the discharge position is typically larger than in the collapsed state, in which segments are retracted together as far as possible and the outer diameter is minimal.

At the beginning of an observation period, the distance of the segment in the discharge position in relation to a reference position further inwards is still minimal. Due to undesired elongation of the link plates and/or undesired widening of the joint bores on the link plate and/or wear of the fastening bolt with which the link plate is joined to the control rod, this distance increases with increasing service life of the reel mandrel. If the recorded distances exceed a predefined upper threshold value over the course of time, this is an indication within the meaning of the disclosure that at least the link plates can show said signs of wear and should therefore be replaced.

In accordance with a further aspect of the method for operating a reel device, it is useful that at least one, but preferably all, of the operating positions is in the elastic linear spring range of the compression spring unit. This is a prerequisite for ensuring that the operating positions can be reversibly controlled again and again during the service life of the reel mandrel and that the distances measured during the service life between an approached operating position and the stationary reference position can be objectively compared with one another. If the operating positions were in the non-linear spring range of the compression spring unit, they would be in the range of plastic deformation of the compression spring unit; an objective evaluation of the distances would then no longer be possible.

Advantageously, the method for operating a reel device not only serves for identifying possible wear conditions of internal components of the reel mandrel, but also for initiating appropriate maintenance as early as possible before individual components fail or undesired losses in the quality of the strip to be wound occur.

Modern reel devices are designed for use in the harsh everyday operating conditions of a rolling mill; accordingly, wear conditions typically do not occur shortly after commissioning but only after a longer service life, typically multiple weeks or months, of the reel mandrel. Therefore, it is useful to compare the distances between an operating position and a stationary reference position measured and recorded only at longer intervals, preferably at intervals of multiple months. This is not precluded by the fact that the distances between the operating positions and the reference positions can also be measured at shorter intervals, preferably also continuously during the service life of the reel mandrel.

The above-mentioned object of the disclosure is further achieved by a computer program product and a reel device. The advantages of these solutions correspond to the advantages mentioned above with reference to the claimed method.

BRIEF DESCRIPTION OF THE DRAWINGS

The description is accompanied by a total of 11 figures.

FIG. 1 shows a reel device;

FIG. 2 shows a compression spring unit with its characteristic curve;

FIG. 3 shows a longitudinal section through a reel mandrel with the segments in a first operating position without wear;

FIG. 4 shows the longitudinal sectional view in accordance with FIG. 3 with the extended segments in the first operating position with wear present;

FIG. 5 shows a diagram for illustrating the change in the distances A1 during the service life;

FIG. 6 shows a longitudinal section through the reel mandrel with the segments in a second operating position without wear;

FIG. 7 shows the longitudinal sectional view in accordance with FIG. 6 with the segments in the second operating position with wear present;

FIG. 8 shows a diagram for illustrating the change in the distances A2 over time during the service life of the reel mandrel;

FIG. 9 shows a longitudinal sectional view of the reel mandrel with the segments in a third operating position without wear;

FIG. 10 shows the longitudinal sectional view in accordance with FIG. 9 with wear present; and

FIG. 11 shows the change in distance A3 during the service life of the reel mandrel.

DETAILED DESCRIPTION

The invention is described in detail below with reference to the specified figures in the form of exemplary embodiments. In all figures, the same technical elements are designated with the same reference signs.

FIG. 1 shows a reel device 100. It has a reel mandrel 120 for winding up a strip, in particular a metal strip. The reel mandrel 120 is driven in rotation by a rotary drive device 130. The rotary drive device 130 is controlled by a control device 140. The reel mandrel itself has a control rod 122, which can be axially moved within the reel mandrel 120 with the aid of a push/thrust drive 110. The push/thrust drive 110 is likewise controlled by the control device 140. The reel mandrel 120 has at least one, but typically a plurality of radially expandable segments 124 at its periphery, which are arranged in a manner distributed over the perimeter of the reel mandrel 120. The segments 124 are typically joined to the control rod 122 via at least two link plates 125, 126. In this manner, the segments 124 can be radially extended into different operating positions and also retracted again, depending on the axial movement position of the control rod 122. The segments 124 are in each case held under a radial preload FD with the aid of at least one compression spring unit between the segment and the control rod. The compression spring units 150 are guided in a radial direction in the reel device 100 with the aid of guides 128, see FIG. 3. When the segment is extended/retracted in a radial direction, the compression spring units 150 are likewise moved in a radial direction. This is carried out by sliding along a ramp 123 of the control rod 122 with the inclined lower sides of their housings if the control rod is moved in the axial direction.

FIG. 2 shows the compression spring unit 150, which holds the segment 124 under the radial preload FD. For the present disclosure, it is assumed that the compression spring unit 150 is operated in a manner wear-free in its elastic working range. The compressive force FD exerted by the compression spring unit 150 is linearly dependent on its spring travel.

The linearly increasing characteristic curve in FIG. 2 shows the radial movement of the surface of the housing 153 as a function of the spreading stroke of the control rod 122 with its ramp 123. The simultaneous radial movement of the unloaded (i.e. no strip is wound up) segments 124 shows the bent curve above them. The non-linear course is due to the fact that the link plates 125, 126 perform a rotational movement about their bearing point during radial expansion. The spring in the compression spring unit 150 compensates for the discrepancy between linear movement and rotational movement with the spring travel. As a result, the segment 124 is always tensioned radially outwards in the unloaded state.

FIG. 3 shows a longitudinal section through the reel mandrel 120 in detail. The compression spring unit 150 can be seen, which presses against the segment 124 from below with the compressive force FD exerted by it and in this manner holds the segment under a radial preload. The compression spring unit 150 is guided in the radial direction R and slides with the inclined lower side of its housing 153 on a ramp 123 of the control rod 122. If the control rod 122 is moved in the axial direction L, said sliding movement occurs and the compression spring unit 150 is moved in the radial direction in this manner. Since the compression spring unit 150 holds the segment 124 under said preload, not only the compression spring unit 150, but also the segment 124, is radially moved/positioned when the control rod 122 is axially moved. Specifically, the segment 124 can be moved/positioned in different radial operating positions in this manner. So that said preload can be built up on the segment 124, this is limited in its radial freedom of movement against the compressive force FD of the compression spring unit 150 with the aid of two link plates 125, 126. The link plates 125, 126 are in each case joined at one of their lower ends to the reel mandrel 120, in particular the control rod 122, via fastening bolts 121, and in each case they have an elongated hole at their opposite upper end, in which the segment 124 is mounted in a joined manner.

As can also be seen in FIG. 6, the surface/upper side of the housing 153 of the compression spring unit 150 forms an upper/inner stop for the compression of the compression spring unit. That is, at maximum compression, the segment 124 rests on the surface of the housing 153 of the compression spring unit 150.

A distance sensor 160 is provided for measuring the distance of the segment 124 in a first operating position P1, in a second operating position P2 or in a third operating position P3, in each case in relation to a stationary operating position P0. This stationary operating position P0 is selected in FIG. 3, for example, in the form of the upper edge of the radial guide 128. In principle, however, any other position in space that is stationary in relation to the relative movement of the segment 124 is also suitable as the reference position.

In the lower half of FIG. 3, a measurement chain is shown for the measurement signal measured by the distance sensor 160, which represents the direct or indirect radial distance of the segment 124 in one of the operating positions in each case. The distance values determined by the distance sensor are recorded in a recording device 170 and evaluated in an evaluation device 180 in terms of any wear condition of individual components of the reel mandrel. In the event of identified wear, a corresponding message is sent to an operator of the reel device 100/to an alarm center, preferably together with a recommendation to replace the worn components of the reel mandrel 120. The output of the message is symbolized in the measurement chain by the reference sign 190.

The design of the reel device 100 and in particular of the reel mandrel 120 just described with reference to FIG. 3 applies equally to FIGS. 4, 6 and 7 and to FIGS. 9 and 10.

The method for operating the reel mandrel described is explained in more detail below with reference to the figures mentioned for different operating positions. FIGS. 3, 6 and 9 in each case show the reel mandrel in a wear-free state, while FIGS. 4, 7 and 10 show the reel mandrel with wear.

For identifying a wear condition of the link plates 125, 126, the method for operating a reel device provides that the segment 124 is moved multiple times into a first operating position P1, also referred to as the approach position, during the service life of the reel device. The radial movement is carried out in each case under the preload applied by the compression spring unit 150. In the approach position, the segment 124 has moved up slightly in the radial direction in relation to the collapsed state of the reel mandrel, specifically to a distance A1 in relation to the stationary reference position P0. The radial distance A1 is determined and recorded at different points in time during the service life. The joint bores 127 in the link plates 125, 126 are subject to wear during the service life of the reel mandrel due to the large radial forces acting on them; i.e., these joint bores 127 can “wear out.” Alternatively or additionally, the link plates 125, 126 themselves may also be subject to wear, in which they undergo plastic elongation with increasing endurance. The fastening bolts 121 can also wear locally with the consequence that their diameter is then reduced locally, for example. These three aforementioned wear phenomena result in the measured radial distances A1 for the first operating position P1 becoming increasingly larger during the service life of the reel mandrel 120. Therefore, the recorded distances A1 are evaluated in accordance with the method for operating a reel device to determine whether they exceed a predefined upper threshold value S1 at a certain point in time during the service life. If the reaching or exceeding of this first upper threshold value S1 is identified, the method for operating a reel device provides for indirect identification/inference of said wear conditions of the link plates 125, 126 or the fastening bolts 121.

As mentioned above, FIG. 3 shows a wear-free/low-wear condition of the reel mandrel, in which the determined distance A1 is still smaller than the first upper threshold value S1. In contrast, FIG. 4 shows the same reel mandrel 120 in a state in which the link plates 125, 126, their joint bores 127 and/or the fastening bolts 121 are subject to wear. The wear condition can be seen in FIG. 4 in that the determined distance A1 is greater than in FIG. 3 and has already reached the upper threshold value S1.

FIG. 5 illustrates the development of the distances A1 over time during the service life of the reel mandrel 120. It can be seen that the measured distances A1 are smaller at an early point in time, at which the link plates 125, 126 are not yet subject to any or only slight wear, than at a later point in time, at which the link plates are subject to wear. FIG. 5 schematically shows the distances determined at different points in time in each case, wherein each black dot corresponds to the distance determined at a certain point in time. Over the course of time/during the service life of the reel mandrel, a movement of such a cluster of measured values towards larger distances can be identified. In practice, instead of the large number of individual measured values, it may be advisable to determine and evaluate average values of the distances A1 in certain time windows.

FIGS. 3, 4 and 5 illustrate the method for operating a reel device, as already mentioned, for the first operating position, i.e. the so-called “approach position,” as explained above in the general part of the description.

In contrast, FIGS. 6, 7 and 8 relate to the method for operating a reel device in the so-called “winding position,” as likewise explained above in the general part of the description. In FIGS. 6 and 7, it can be seen that in the second operating position, i.e. the winding position, the compression spring unit 150 is maximally compressed, i.e. the segment 124 rests on the upper edge of the housing 153 of the compression spring unit 150. The radial compression force, which counteracts the compressive force FD of the compression spring unit 150, is generated by the strip tension of the plurality of coil turns of the strip 20, which are wound up onto the segments 124 of the reel mandrel 120 in the winding position. At the same time, the compression spring unit 150 is extended in the winding position in the radial direction to the distance A2 in relation to the stationary reference position P0, in order to ensure a sufficiently tight coil of the strip 20 on the segments 124. In the wear-free state, as shown in FIG. 6, the distance A2 is greater than a lower threshold value S2. The radial extension of the segments 124 to the distance A2 is carried out by moving the control rod 122 axially to the left; the compression spring unit 150, which is guided in the radial direction R by the guides 128, then slides upwards in the radial direction R on the ramp 123 of the control rod 122.

During the service life of the reel mandrel 120, the sliding surface 129 between the inclined lower side of the housing 153 of the compression spring unit 150 and the upper side of the ramp 123 is subject to wear, as shown in FIG. 7. Due to wear, i.e. as a result of abrasion, the sliding surface 129 in FIG. 7 is lowered in relation to the wear-free state in accordance with FIG. 6. Therefore,

• • when the control rod 122 is moved axially by the same amount, the compression spring unit 150 no longer reaches the same radial distance A2 as without wear in accordance with FIG. 6. Rather, the radial extension state, represented by the distance A2 of the segment 124 in relation to the stationary reference position P0, decreases continuously during the service life of the reel mandrel, see FIG. 8. As soon as the wear has reached a certain size, the radial distance A2 drops to the lower distance threshold value S2 or below. If the evaluation of the radial distances in accordance with the method for operating a reel device identifies this situation, the presence of severe wear of said sliding surfaces is inferred and a corresponding recommendation for replacing the control rod 122 and/or the housing 153 is issued.

Finally, FIGS. 9 to 11 relate to a third operating position for the reel mandrel, the so-called “discharge position.” FIG. 9 shows a wear-free state; FIGS. 10 and 11 show the state with wear. Once the strip 20 has been completely wound into a coil in the winding position, the segments on the reel mandrel must be retracted radially slightly, in order to be able to pull the coil off the reel mandrel. This position of the segments is said discharge position, represented in FIGS. 9 to 11 by the radial distance A3 in relation to the stationary reference position P0. The distance A3 measured at different points in time during the service life of the reel mandrel 120 is also suitable for indirectly identifying a wear condition of the link plates 125, 126, of their joint bores 127 and/or of the fastening bolts 121. For the transition from the winding position to the discharge position, the control rod 122 is moved to the right, as a result of which the compression spring unit 150 is lowered on the ramp 123 in a sliding manner to the distance A3. In the wear-free state of the link plates in accordance with FIG. 9, the radial distance A3/the third operating position is below a predetermined second upper threshold value S3. As can be seen in FIGS. 10 and 11, this radial distance A3 increases with increasing wear during the service life of the reel mandrel 120. After a certain service life, the radial distance A3 reaches the upper threshold value S3. In this case, the method for operating a reel device indirectly identifies the presence of said wear condition in the link plates 125, 126, in their joint bores 127 and/or in the fastening bolts 121 for the link plates. In this case as well, said wear condition is reported and the replacement of the link plates is recommended.

LIST OF REFERENCE SIGNS

• • 20 Strip, in particular metal strip
  • 100 Reel device
  • 110 Push/thrust drive for control rod
  • 120 Reel mandrel
  • 121 Fastening bolt for link plate
  • 122 Control rod
  • 123 Ramp
  • 124 Segment
  • 125, 126 Link plate
  • 127 Joint bore in the link plate
  • 128 Radial guide for compression spring unit
  • 129 Sliding surface between compression spring unit and ramp
  • 130 Rotary drive device
  • 140 Control device
  • 150 Compression spring unit
  • 153 Housing
  • 160 Distance sensor
  • 170 Recording device
  • 180 Evaluation device
  • 190 Output of message
  • A1 Radial distance
  • A2 Radial distance
  • A3 Radial distance
  • FD Radial compressive force, radial preload
  • L Axial direction
  • P0 Stationary reference position
  • P1 1. Operating position (=wrapping position)
  • P2 2. Operating position (=winding position)
  • P3 3. Operating position (=discharge position)
  • R Radial direction
  • S1 Upper distance threshold value for wrapping position
  • S2 Lower distance threshold value for winding position
  • S3 Upper distance threshold value for discharge position