WO2024074251A1

WO2024074251A1 - Method, reel device and computer program for operating the reel device

Info

Publication number: WO2024074251A1
Application number: PCT/EP2023/073877
Authority: WO
Inventors: Johannes Alken; Benjamin VIEREC; Thomas Holzhauer; Johannes LEIPOLD
Original assignee: Sms Group Gmbh
Priority date: 2022-10-05
Filing date: 2023-08-31
Publication date: 2024-04-11
Also published as: DE102022210533A1

Abstract

The invention relates to a method and a computer program for operating a reel device (100). The reel device (100) comprises a reel mandrel (120) for winding up a strip material (20). For this purpose, the reel mandrel has a plurality of segments (124) distributed over the perimeter thereof, which are each joined, via at least two link plates, to a control rod (122) that can be axially moved in the reel mandrel, for radially extending and retracting the segment into at least one operating position. In order to be able to reliably identify wear statuses of internal components of the reel mandrel that are not visible from the outside, the method according to the invention provides that, during the service life of the reel device, the segments are repeatedly moved into determined operating positions and the respective distances of the segments in relation to a stationary operating position are determined. The distances recorded at different times are then evaluated in terms of whether they exceed or fall below a predefined threshold value during the service life of the reel device. In this case, it is concluded that there is wear.

Description

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

The invention relates to a method for operating a reeling device, wherein the reeling 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 around its circumference, each of which is articulated via at least two tabs to a control rod that is axially displaceable in the reel mandrel for radially extending and retracting the segment into at least one operating position. The invention also relates to the reeling device itself.

Such reeling devices are well known and are subjected to high mechanical stress in the day-to-day operation of a rolling mill. Accordingly, wear on the moving parts of the reel mandrel is unavoidable. A distinction must be made between wear that can be seen from the outside and wear that cannot be seen from the outside. The Japanese patent application JP 2000-226141 A deals with wear that occurs on the outside of the segments on which the strip or metal strip is wound.

In contrast, there is currently no way of detecting wear on the lugs or the housing of the compression spring unit when the reel mandrel is installed. There are soft indicators, such as the "clattering" of the segments when the reel is idle or indirect measurements with pressure rollers, which indicate wear on the internal components of the reel mandrel. The reel mandrel is also typically serviced regularly when the "wound tonnage" has exceeded a specified weight threshold. However, the methods mentioned do not allow for a precise statement about the optimal time to replace the wearing parts. In this respect, a wear-optimized service life of the reel mandrel is not possible. This means that Unnecessary costs arise due to suboptimal use of the reel dome’s service life.

The invention is based on the object of developing a known method and computer program for operating a reeling device as well as a corresponding known reeling device itself in such a way that even wear conditions of internal components of the reel mandrel that cannot be recognized from the outside are reliably detected without the reel mandrel having to be disassembled into its components.

This object is achieved by the method claimed in patent claim 1. The method is characterized by the following steps: b) directly or indirectly determining and storing the radial distance of the segment in the operating position with respect to a fixed reference position at different times during the period of use; c) evaluating the distances stored at the different times with regard to whether they exceed a predetermined upper threshold value or fall below a predetermined lower threshold value during the period of use of the reel device; and d) indirectly detecting a state of wear of the reel device if the recorded radial distances exceed the upper threshold value or fall below the lower threshold value from one of the times.

If individual internal components of the reel dome are subject to wear during their service life, this leads to various predetermined operating positions for the segments of the reel dome, which could still be reached at an initial time of use, no longer being able to be reached precisely at a later time of use after interim use and wear. In particular, the controlled operating positions at the later time of use no longer correspond to the operating positions as they were controlled at the first time of use, e.g. when the reel dome was in new condition. The difference in the controlled operating positions is reflected in changing distances between the controlled operating positions and fixed reference positions over the service life of the reel dome.

The present invention provides for determining the change in the controlled operating positions over the service life of the reel mandrel in order to be able to draw conclusions 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 formulation “Direct or indirect determination and storage of the radial distance...”, “direct determination” means the actual determination of the concrete radial distance. In contrast, “indirect determination” means the determination of a physical quantity representing the radial distance.

The term "determining and storing the radial distance of the segment ... at different times during the deployment period" also includes a so-called "time-continuous" determination and storage of the distances with arbitrarily small temporal resolution. Two of these points in time limit an observation period during the deployment period.

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

The term “indirect detection” refers to the fact that the wear conditions are not directly visible to an observer from the outside, because components inside the reel mandrel can be affected by wear. If the determined and stored distances have their corresponding If the wear conditions are exceeded or not met within predetermined threshold values, conclusions can be drawn about the wear conditions.

In general, whether the observed distances increase or decrease due to the wear to be determined here depends on the position of the fixed reference position in relation to the segments. In this description, it is generally assumed that the fixed reference position is located 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 fixed reference position. In principle, however, any other fixed position in space can be selected as the reference position; for example, fixed points in space that are radially further out than the segments can also be selected as the reference position. In this case, the inventive evaluation of the stored distances with regard to whether they exceed or fall below a threshold value over the course of their service life must be reversed. This is what is meant by the wording "or vice versa".

The present invention assumes that the compression spring unit is not subject to wear.

The present invention provides for an at least temporary intelligent evaluation of the distances between the segments in an operating position compared to a fixed reference position during their service life, preferably starting with the new state or a comparable fault-free state after maintenance. The method according to the present invention allows an accurate statement to be made on the basis of these stored distances regarding the wear pattern of the main wear parts of the reel mandrel. By carrying out the method according to the invention, the user of the reel mandrel can recognize a gradual wear of internal components of the reel mandrel quite precisely and thus carry out a targeted change or a targeted Schedule maintenance of the coiler mandrel during an upcoming downtime of the coiler mandrel without having to take the system out of operation excessively.

According to a first embodiment, the first operating position is a pre-spread winding position of the segment without wound band. If, over the course of the service life of the reeling device, when approaching the winding position, an increasing increase in the distance of the segment in the winding position compared to the fixed reference position is determined, then according to the invention, a conclusion is drawn about the state of wear in the form of an undesirable elongation of the lashing and/or a deflection of joint holes on the lashings and/or wear on the fastening bolt with which the lashings are articulated on the control rod. This applies in particular if the stored distances exceed the specified upper threshold value, or vice versa.

According to a second alternative 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 onto the segment and the reel mandrel. If, for this operating position, an increasing reduction in the distance of the segment compared to the stationary reference position located radially further inside is determined over the period of use of the reel device, the method according to the invention provides that the state of wear is inferred in the form of undesirable abrasion on the surface of the ramp on the outside of the control rod and/or on the underside of the housing of the compression spring unit. This applies in particular if the distances stored over the period of use fall below the predetermined lower threshold value. The terms “winding position” for the first operating position and “winding position” for the second operating position must be fundamentally distinguished from one another. In the context of the present invention, the winding position refers to a position in which the segments are slightly extended in the radial direction compared to their collapsed position and in which winding of the strip on the reel mandrel or on the segments of the reel mandrel begins. Winding means that initially only a few turns, but not the full length of the strip, are wound onto the reel mandrel. When winding typically 1-7 turns of the strip on the reel mandrel, the wound strip exerts a radial compression force on the compression spring unit of the reel mandrel due to increasing strip tension, counter to the radially outward-acting spring pressure force of the compression spring unit. As a result, this leads to the at least one segment being displaced into a compression position that is radially further inward than the winding position.

In order to ensure that there is sufficient static friction between the segments and the innermost layer of the wound strip for the subsequent continuation of the winding process of the strip, the segment is then moved radially further outwards from the compression position into a winding position before the winding process is continued, in which the winding of the reel mandrel with the strip continues. The winding position can coincide in radial direction with the starting winding position; however, the winding position can also be radially further inwards or further outwards compared to the starting winding position. This depends on the predetermined force with which the segments are to be pressed against the winding of the strip to be wound.

According to a third embodiment, the operating position is the discharge position of the segment on the reel mandrel. This means: 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 on the reel mandrel. In this discharge position It is therefore possible to discharge a previously wound coil from the reel dome. However, the outer diameter of the segments in the discharge position is typically larger than in the collapsed state, in which the segments are moved as far together as possible and the outer diameter is minimal.

At the beginning of an observation period, the distance of the segment in the discharge position compared to a reference position located further radially inward is still minimal. Due to an undesirable elongation of the tabs and/or an undesirable deflection of the joint holes on the tab and/or wear of the fastening bolt with which the tab is hinged to the control rod, this distance becomes larger and larger as the reel mandrel is used for longer. If the stored distances exceed a predetermined upper threshold value over time, then this is an indication within the meaning of the invention that at least the tabs may exhibit the aforementioned signs of wear and should therefore be replaced.

According to a further aspect of the method according to the invention, it is sensible that at least one, but preferably all of the operating positions are in the elastic linear spring range of the compression spring unit. This is a prerequisite for the operating positions to be able to be controlled reversibly again and again during the service life of the reel mandrel and for the distances measured over the course of the service life between an operating position approached and the fixed reference position to 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 a plastic deformation of the compression spring unit; an objective evaluation of the distances would then no longer be possible. Advantageously, the method according to the invention serves not only to detect possible wear conditions of internal components of the coiler mandrel, but also to initiate appropriate maintenance as early as possible, before a failure of individual components or undesirable losses in the quality of the strip to be wound up occur.

Modern coiling devices are designed for use in the rough everyday operating conditions of a rolling mill; accordingly, wear and tear typically does not occur shortly after commissioning, but only after a longer period of use of the coiling mandrel, typically several weeks or months. It is therefore sensible to compare the distances between an operating position and a fixed reference position recorded and stored according to the invention only at longer intervals, preferably at intervals of several months. This does not contradict the fact that the distances between the operating positions and the reference positions can also be recorded at shorter intervals, preferably continuously during the period of use of the coiling mandrel.

The above-mentioned object of the invention is further achieved by a computer program product according to claim 9 and a reel device according to claim 10. The advantages of these solutions correspond to the advantages mentioned above with reference to the claimed method.

Further advantageous embodiments are the subject of the dependent claims.

The description includes a total of 11 figures, of which

Fig. 1 a reeling device; Fig. 2 a compression spring unit with its characteristic curve;

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

Fig. 4 shows the longitudinal sectional view according to Fig. 3 with the extended segments in the first operating position with existing wear;

Fig. 5 is a diagram illustrating the change of the distances A1 during the period of use;

Fig. 6 a longitudinal section through the coiler mandrel with the segments in a second operating position without wear;

Fig. 7 shows the longitudinal sectional view according to Fig. 6 with the segments in the second operating position with existing wear;

Fig. 8 is a diagram illustrating the temporal change of the distances A2 during the service life of the reel dome;

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

Fig. 10 the longitudinal section according to Fig. 9 with existing wear; and

Fig. 11 shows the change of the distance A3 during the service life of the reel dome. The invention is described in detail below with reference to the figures mentioned in the form of exemplary embodiments. In all figures, the same technical elements are designated by the same reference numerals.

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 rotationally driven 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 displaced within the reel mandrel 120 with the aid of a pressure/thrust drive 110. The pressure/thrust drive 110 is also controlled by the control device 140. The reel mandrel 120 has at least one, but typically a plurality of, radially expandable segments 124 on its periphery, which are distributed over the circumference of the reel mandrel 120. The segments 124 are typically articulated to the control rod 122 via at least two tabs 125, 126. In this way, the segments 124 can be radially extended into different operating positions and also retracted again, depending on the axial displacement position of the control rod 122. The segments 124 are each 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 the reel device 100 in the radial direction with the aid of guides 128, see Fig. 3. When the segment is extended or retracted in the radial direction, the compression spring units 150 are also moved in the radial direction. This is done by sliding along a ramp 123 of the control rod 122 with the sloping undersides of their housings when the control rod is displaced 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 invention, it is assumed that the compression spring unit 150 is 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 rising 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 tape is wound on) segments 124 is shown by the curved curve above. The non-linear progression is related to the fact that the tabs 125, 126 perform a rotational movement around their bearing point during radial spreading. 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 pressure force FD exerted by it and in this way holds the segment under a radial preload. The compression spring unit 150 is guided in the radial direction R and slides with the sloping underside of its housing 153 on a ramp 123 of the control rod 122. When the control rod 122 is moved in the axial direction L, the aforementioned sliding movement occurs and the compression spring unit 150 is thus moved in the radial direction. Because the compression spring unit 150 holds the segment 124 under the aforementioned preload, when the control rod 122 is axially moved, not only the compression spring unit 150 but also the segment 124 is radially displaced or positioned. Specifically, the segment 124 can be displaced or positioned in various radial operating positions in this way. In order to build up the pre-stress mentioned on the segment 124, the latter is limited in its radial freedom of movement against the pressure force FD of the compression spring unit 150 by means of two tabs 125, 126. The tabs 125, 126 are each attached with their lower end to the coiler mandrel via fastening bolts 121. 120, in particular the control rod 122, are articulated and they each have an elongated hole at their opposite upper end in which the segment 124 is articulated.

As can be further seen in Fig. 6, the surface or top of the housing 153 of the compression spring unit 150 forms an upper or inner stop for the compression of the compression spring unit. This means that 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 detecting the distance of the segment 124 in a first operating position P1, in a second operating position P2 or a third operating position P3, in each case relative to a fixed operating position PO. This fixed operating position PO 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 fixed relative to the relative movement of the segment 124 is also suitable as a reference position.

The lower half of Fig. 3 shows a measuring chain for the measurement signal recorded by the distance sensor 160, which represents the direct or indirect radial distance of the segment 124 in each of the operating positions. The distance values determined by the distance sensor are stored in a storage device 170 and evaluated in an evaluation device 180 with regard to any wear and tear of individual components of the coiler mandrel. If wear is detected, a corresponding message is sent to an operator of the coiler device 100 or to a reporting center, preferably together with a recommendation to replace the worn components of the coiler mandrel 120. The output of the message is symbolized in the measuring chain by the reference number 190. The structural design of the reeling device 100 and in particular of the reeling mandrel 120 just described with reference to Fig. 3 applies equally to Figs. 4, 6 and 7 as well as to Figs. 9 and 10.

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

In order to detect a state of wear of the tabs 125, 126, the method according to the invention provides that the segment 124 is moved several times over the service life of the reel device into a first operating position P1, also called the start-up position. The radial movement takes place under the preload applied by the compression spring unit 150. In the start-up position, the segment 124 is moved a little way in the radial direction compared to the collapsed state of the reel mandrel, specifically to a distance A1 compared to the fixed reference position PO. The radial distance A1 is determined and stored at different times over the service life. The joint holes 127 in the tabs 125, 126 are subject to wear over the service life of the reel mandrel due to the large radial forces acting; i.e. these joint holes 127 can "wear out". Alternatively or additionally, the tabs 125, 126 themselves can also be subject to wear, in which they experience plastic elongation with increasing endurance. The fastening bolts 121 can also wear locally, with the consequence that, for example, their diameter is reduced locally. These three wear phenomena mentioned lead to the measured radial distances A1 for the first operating position P1 becoming increasingly larger over the course of the service life of the reel mandrel 120. The stored distances A1 are therefore evaluated according to the method according to the invention to determine whether they have a exceed the predetermined upper threshold value S1. If the reaching or exceeding of this first upper threshold value S1 is detected, the method according to the invention provides for an indirect detection or a conclusion about the said wear conditions of the tabs 125, 126 or the fastening bolts 121.

As mentioned above, Fig. 3 shows a wear-free or low-wear state 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 tabs 125, 126, their joint holes 127 and/or the fastening bolts 121 are subject to wear. The state of wear is shown in Fig. 4 in that the determined distance A1 is larger in comparison to Fig. 3 and has specifically already reached the upper threshold value S1.

Fig. 5 illustrates the temporal development of the distances A1 over the course of the service life of the reel mandrel 120. It can be seen that the measured distances A1 at an early point in time, when the tabs 125, 126 are not subject to any or only slight wear, are smaller than at a later point in time, when the tabs are subject to wear. Fig. 5 shows schematically the distances determined at different points in time, with each black dot corresponding to the distance determined at a specific point in time. Over time or over the service life of the reel mandrel, a shift of such a cluster of measured values towards larger distances can be seen. In practice, it is advisable to determine average values of the distances A1 in certain time windows and to evaluate these instead of the large number of individual measured values.

Figures 3, 4 and 5 illustrate the method according to the invention, as stated, for the first operating position, ie the so-called start-up position, as explained above in the general part of the description. 6, 7 and 8 relate to the method according to the invention in the so-called winding position, as also 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 windings of the strip 20 which are wound 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 radial direction to the distance A2 from the fixed reference position PO in the winding position in order to ensure sufficiently firm winding of the strip 20 onto 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 takes place by axially moving the control rod 122 to the left; the compression spring unit 150 guided in the radial direction R through the guides 128 then slides upwards in the radial direction R on the ramp 123 of the control rod 122.

Over the course of the service life of the coiler mandrel 120, the sliding surface 129 between the slanted underside of the housing 153 of the compression spring unit 150 and the top of the ramp 123 is subject to wear, as shown in Fig. 7. Due to the wear, i.e. as a result of wear, the sliding surface 129 in Fig. 7 is lowered compared to the wear-free state according to Fig. 6. Therefore, when the control rod 122 is moved axially, the compression spring unit 150 no longer reaches the same radial distance A2 by the same amount as without wear according to Fig. 6. Rather, the radial extension state, represented by the distance A2 of the segment 124 compared to the fixed reference position PO, decreases continuously over the service life of the coiler mandrel, see Fig. 8. As soon as the wear has reached a certain level, the radial distance A2 to the lower distance threshold value S2 or below. If the evaluation of the radial distances according to the method according to the invention detects this situation, it is concluded that there is severe wear on the said sliding surfaces and a corresponding recommendation is issued to replace the control rod 122 and/or the housing 153.

Finally, Fig. 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; Fig. 10 and 11 relate to the state with wear. After the strip 20 has been wound into a coil in the winding position, the segments on the reel mandrel must be retracted radially a little in order to be able to pull the coil off the reel mandrel. This position of the segments is the discharge position mentioned, represented in Fig. 9 to 11 by the radial distance A3 from the fixed reference position PO. The distance A3 recorded at various times during the service life of the reel mandrel 120 is also suitable for indirectly detecting a state of wear of the tabs 125, 126, of their joint holes 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, whereby the compression spring unit 150 is slidably lowered on the ramp 123 to the distance A3. In the wear-free state of the tabs according to Fig. 9, the radial distance A3 or the third operating position is below a predetermined second upper threshold value S3. As can be seen from Figs. 10 and 11, this radial distance A3 increases over the service life of the reel mandrel 120 with increasing wear. After a certain service life, the radial distance A3 reaches the upper threshold value S3. In this case, the method according to the invention indirectly detects the presence of the said wear condition in the tabs 125, 126, in their joint holes 127 and/or in the fastening bolts 121 for the tabs. In this case, too, the wear condition is reported and replacement of the tabs is recommended.

List of reference symbols

20 Band, especially metal band

100 reel device

110 Push-Z-thrust drive for control rod

120 reel dome

121 Fastening bolt for tab

122 Control rod

123 Ramp

124 Segment

125, 126 tab

127 Joint hole in the tab

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 Storage facility

180 Evaluation device

190 Issue Message

A1 radial distance

A2 radial distance

A3 radial distance

FD radial compressive force, radial preload

L axial direction

PO fixed reference position

P1 1. Operating position (= winding position) P2 2nd operating position (= winding position)

P3 3. Operating position (= discharge position)

R radial direction

S1 upper distance threshold for winding position S2 lower distance threshold for winding position

S3 upper distance threshold for discharge position

Claims

Patent claims:

1. Method for operating a reel device (100), wherein the reel device has a reel mandrel (120) for winding up a strip (20), in particular a metal strip, wherein the reel mandrel (120) has at least one segment (124) distributed around its circumference, which is articulated via at least two tabs (125, 126) to a control rod (122) axially displaceable in the reel mandrel (120) for radially moving the segment (124) into at least one predetermined operating position (P1, P2, P3), and wherein the reel mandrel (120) has at least one compression spring unit (150) for holding the segment (124) under a radial preload (FD); comprising the following steps: a) multiple movement of the segment (124) over the course of the service life of the reel device (100) into the operating position (P1, P2, P3), each time under the preload (FD), the tabs (125, 126) and/or the control rod (122) being subject to wear; characterized by b) directly or indirectly determining and storing the radial distance (A1, A2, A3) of the segment (124) in the operating position with respect to a fixed reference position (PO) at different points in time during the service life; c) evaluating the distances (A1, A2, A3) stored at the different points in time with regard to whether they exceed a predetermined upper threshold value (S1, S3) or fall below a predetermined lower threshold value (S2) over the course of the service life of the reel device (100); and d) Indirect detection of a state of wear of the reel device (100) if the detected radial distances (A1, A2, A3) exceed the upper threshold value (S1, S3) from one of the points in time or the lower threshold value (S2). Method according to claim 1, characterized in that a first operating position (P1) is a pre-spread winding position of the segment (124) without wound strip (20); that in step c) over the course of the service life of the reel device (100) an increasing increase in the distance (A1) is determined; and that in step d) the wear state in the form of an undesirable elongation of the tabs (125, 126), a deflection of joint bores (127) on the tabs and/or of their fastening bolts (121) is indirectly detected if the stored distances (A1) exceed the predetermined upper threshold value (S1), or vice versa. Method according to claim 1, characterized in that the control rod (122) has at least one ramp (123) on its circumference; that the compression spring unit (150) has a housing (153) with a sloping underside; and that the housing of the compression spring unit (150) slides along the ramp (123) with its sloping underside when the segment (124) is moved radially during an axial movement of the control rod; that a second operating position (P2) is a winding position of the segment (124) in which a plurality of turns of the band (20) are wound onto the segment and the reel mandrel (120); that in step c) over the course of the service life of the reel device (100) an increasing reduction in the distance (A2) is determined; and that in step d) the state of wear in the form of undesirable abrasion on the surface of the ramp (123) and/or on the underside of the Housing (153) of the compression spring unit (150) is indirectly detected when the stored distances fall below the predetermined lower threshold value (S2).

4. Method according to claim 3, characterized in that a transition from a winding position (P1) to the winding position (P2) comprises the following steps:

- winding the strip (20) with 1-7 windings on the winding mandrel (120) with the segment (124) in the winding position (P1), whereby a radial compression force is exerted on the compression spring unit (150) and the segment (124) is moved into a compression position; and

- moving the segment again against the compression force from the compression position into the winding position for further winding the coiler mandrel with the strip (20) to form a coil.

5. Method according to claim 1, characterized in that a third operating position (P3) is the discharge position of the segment from the coiler mandrel; that in step c) over the course of the service life of the coiler device (100) an increasing increase in the distance (A3) of the segment (124) compared to the radially inner reference position (PO) is determined, or vice versa; and that in step d) the state of wear in the form of an undesirable elongation of the tabs (125, 126), a deflection of joint bores (127) on the tabs and/or of their fastening bolts (121) is indirectly detected when the stored distances (A3) exceed the predetermined upper threshold value (S3), or vice versa.

6. Method according to one of the preceding claims, characterized in that the upper and lower threshold values (S1, S2, S3) and at least one, preferably all of the operating positions (P1, P2, P3) each lie in the elastic spring range of the compression spring unit (150).

7. Method according to one of the preceding claims, characterized in that in a step e) a maintenance of the coiler mandrel (120) is initiated if a wear condition is indirectly detected in step d).

8. Method according to one of the preceding claims, that the movement of the segment (124) into the operating position and the determination and storage of the radial distance (A1, A2, A3) of the segment (124) in the operating position takes place several times a day, several times a month or several times a year, preferably continuously; and that the evaluation of the stored distances (A1, A2, A3) takes place with the same or less frequency as the storage of the distances.

9. A computer program product loadable into the internal memory of a digital computer and comprising software code portions for carrying out the steps of the method of any preceding claim when the product is run on a computer.

10. Reeling device (100) with a reel mandrel (120) for winding up a strip, in particular a metal strip, with a rotary drive device (130) for rotary driving of the reel mandrel (120) for a reeling operation of the reeling device (100), with a push/pull drive (110) for axially displacing a control rod (122) in the reel mandrel (120) and with a control device (140) for controlling the rotary drive device (130) and the pressure/thrust drive; wherein the reel mandrel has: the control rod (122); at least one radially expandable segment (124) on the circumference of the reel mandrel (120), wherein the segment is articulated to the control rod (122) via at least two tabs (125, 126) for radially extending and retracting the segment (124) into at least one operating position in accordance with a respective axial displacement position of the control rod (122); at least one compression spring unit (150) arranged between the segment (124) and the control rod (122) for holding the segment (124) under a radial preload; characterized by at least one distance sensor (160) for repeatedly directly or indirectly determining the radial distance (A1, A2, A3) of the segment (124) in the at least one operating position (P1, P2, P3)) with respect to a fixed reference position (PO); a storage device (170) and an evaluation device (180) for storing and evaluating a plurality of the detected distances (A1, A2, A3) with regard to their change over the service life of the reel device (100) and specifically as to whether the detected radial distances (A1, A2, A3) exceed a predetermined upper threshold value (S1, S3) or fall below a predetermined lower threshold value (S2) over time. Reel device (100) according to claim 10, characterized by an inner stop for the compression of the compression spring unit (150) when winding the strip, wherein the stop is formed, for example, by the upper edge of a housing (153) which houses the compression spring unit (150) in the non-compressed state. Reel device (100) according to one of claims 10 or 11, characterized in that the fixed reference position (PO) is formed, for example, by the

Upper edge of a guide (128) in which the compression spring unit (150) is guided radially. Reel device (100) according to one of claims 10 to 12, characterized in that the control device (140) of the reel device (100) is designed to carry out the method according to one of the preceding claims 1 to 8.