EP3551354B1

EP3551354B1 - Width and speed control for sheet metal descaler and methods of using same

Info

Publication number: EP3551354B1
Application number: EP18842696.9A
Authority: EP
Inventors: Kevin C. Voges; Alan R. Mueth; Christopher Craig
Original assignee: Material Works Ltd; Mat Works Ltd
Current assignee: Material Works Ltd; Mat Works Ltd
Priority date: 2018-02-19
Filing date: 2018-02-19
Publication date: 2021-09-08
Anticipated expiration: 2038-02-19
Also published as: EP3551354A4; EP3551354A1; ES2890999T3; ES2890999T8; JP2021514303A; WO2019160563A1

Description

BACKGROUND AND SUMMARY

The present disclosure is directed to a control system for operating a processing line with a sheet metal descaler. US8066549 discloses the features of the preamble of independent claims 1 and 9.
According to the invention, there is provided an apparatus according to claim 1 and a method according to claim 9. Preferred embodiments are further defined in dependent claims.

DESCRIPTION OF THE DRAWINGS

Figure 1 shows a schematic diagram of a control system and sensor components used in a sheet metal processing line having a descaler.
Figure 2 is an exploded, perspective view of an embodiment of a nozzle actuator, nozzle and impeller wheel.
Figure 3 is an exploded, side elevational view of the components of Figure 2.
Figure 4 shows an exemplary blast pattern area for a wide width sheet with an intensity of the spray located generally laterally inward in the blast pattern area toward the center of the sheet.
Figure 5 shows a front view of the blast pattern area of Figure 4.
Figure 6 shows an exemplary blast pattern area for a wide width sheet with an intensity of the spray located generally laterally outward in the blast pattern area toward the lateral edges of the sheet.
Figure 7 shows a front view of the blast pattern area of Figure 6.
Figure 8 shows an exemplary blast pattern area for a narrow width sheet with an intensity of the spray located generally laterally inward in the blast pattern area toward the center of the sheet.
Figure 9 shows a front view of the blast pattern area of Figure 8.
Figure 10 shows an exemplary blast pattern area for a narrow width sheet with an intensity of the spray located generally laterally outward in the blast pattern area toward the lateral edges of the sheet.
Figure 11 shows a front view of the blast pattern area of Figure 10.
Figure 12 shows an embodiment of a process flow for a control for a sheet metal processing line having a descaler.
Figure 13 shows a schematic diagram of a starting nozzle position relative to an impeller wheel for a wide width sheet.
Figure 14 shows a schematic diagram of a starting nozzle position relative to an impeller wheel for a narrow width sheet.

DETAILED DESCRIPTION

US7601226 , US8062095 , US8066549 , US8074331 , US8128460 , US8707529 , and US933625 , describe descaling apparatuses that eliminate scale from the sheet metal. The control system described herein may be used in connection with such sheet metal processing lines. In the following description, the terms "top" and "bottom," "above" and "below," "clockwise" and "counterclockwise," and "upper" and "lower" should not be interpreted as limiting in any way. The terms are used merely for convenience in explaining the relationship of certain elements as they appear in the drawings.
Figure 1 shows a schematic drawing of a control 20. The control 20 includes a processor 22 that receive input from sensors 24a-24e that sense the surface condition of sheet metal 26 as it is processed in a descaler. The sensors may be cameras, profilometers, and/or other measuring devices configured to sense the surface condition of sheet metal as it is being processed in the descaler. The sensors are first and second edge sensors and a center sensor 24c, and may be intermediate sensors 24b,24d. The first and second edge sensors 22a,22e are configured to sense the condition of the surface of the sheet metal 26 at lateral opposite side edges of the sheet metal. The center sensor 24c is configured to sense the condition of the surface of the sheet metal at a center of the sheet metal. Intermediate sensors 24b,24d may be also provided to sense the condition of the surface of the sheet metal 26 at positions intermediate of the center and the lateral opposite side edges of the sheet metal. In certain configurations of processing, for instance, descaling narrow width material, the intermediate sensors may be used as edge sensors and the edge sensors 24a,24e may be disabled from providing input to the control. Each of the sensors may provide input signals to the controller indicative of the condition of the surface of the sheet. A light 28 may also be provided to illuminate the surfaces of the sheet metal to allow the sensors to sense the surface condition of the sheet metal. The signals generated by the sensors are indicative of surface finish and/or general surface condition. The signals may be indicative of brightness, hue, and saturation associated with an image of the surface of the sheet metal. In one example, the control 20 may comprise a system provided by Keyence Corp. of Itasca, IL, and in one embodiment, the processor 22 may include a model CV-X172 image sensor and a model CA-DC21 E light controller. To provide additional input from other cameras to the image sensor, the image sensor portion of the processor 22 may be provided with a model CV-E 500 camera extension unit. The processor may have one or more user interfaces 30 to allow programming of the processor, operation of the control 20, and remote monitoring of the signals obtained by the sensors 24a-24e. For instance, the processor may be programmed to allow remote viewing of the images obtained by the sensors via the user interfaces. The processor 22 may be configured to provide output signals 32,34 to programmable logic controls 36,38 associated with descaler or the processing line in which the descaler is employed. The output signals 32,34 may be provided via an ethernet connection or via an RS-232 type connection. For instance, in a system as described in US8707529 , the control 20 and processor 22 may be interfaced with the programmable logic control 38 associated with the recoiler and its tensioner to control the rate of advancement of the sheet through the descaling cell. The control 20 and processor 22 may also be interfaced with an actuator 36 associated with a nozzle 40 that directs the scale removing media to each impeller wheel 42 that propels scale removing media against the sheet 26.
Figures 2 and 3 provide additional detail of the nozzle actuator 36, nozzle 40, and impeller wheel 42. A supply of scale removing media is directed from a supply 44 to each wheel 42 through the nozzle 40 generally to the center of each impeller wheel. The nozzle 40 is rotatably mounted within hub plates 46, 48 and operatively connected to the nozzle actuator 36 such that operation of the actuator causes rotation of the nozzle 40 within the hub plates. The actuator 36 may be a linear actuator that is operatively pivotally connected to an outer flange of the nozzle 40. Thus, linear motion of the linear actuator may produce rotational motion of the nozzle within the hub plates 46,48. The impeller wheel may be mounted on a shaft 50 driven by an electric motor (not shown). The impeller wheel 42 may have a hollow center that communicates radially with the veins of the impeller wheel. An opening 52 to the hollow center may be provided on the impeller wheel 42 axially opposite the shaft connection 50 to the impeller. The nozzle 40 may extend through the opening 52 and be disposed within the hollow center of the impeller wheel 42 with the hub plates 46,48 and associated disk seals 54 enclosing the opening. The nozzle 40 may have a tapered distal end 56. Actuation of the nozzle actuator 36 may in turn cause rotation of the nozzle 40 within the hub plates 46,48 and orient the tapered end 56 of the nozzle within the hollow center of the impeller wheel 42. Orienting the tapered end 56 of the nozzle at selected positions within the hollow center of the impeller wheel 42 enables changing of the location of the intensity of the spray within the blast pattern area, as will be explained below.
Figures 4-11 show schematic views of the impeller wheels 42 associated with the sheet metal descaler and their positioning to achieve blast pattern areas 60,62 with different locations of spray intensity 64,66 relative to the advancing sheet 26 passing through the descaler. While the drawings show the top of the sheet and impellers propelling scale removing medium against the top of the sheet metal, in addition to or in the alternative, an identical arrangement may also be provided for the bottom of the sheet.
The impeller wheels 42 are arranged on laterally opposite sides (e.g. opposite width edges) of the sheet 26 in a direction transverse to the direction of advancement of the sheet. The first impeller wheel propels scale removing media across the width of the sheet and produces the first blast pattern area 60. The second impeller wheel is positioned offset from the first wheel in the direction of advancement of the sheet so that the scale removing media propelled by the second wheel does not interfere with the scale removing media propelled by the first wheel. The second wheel also propels a scale removing media across the width of the sheet and produces the second blast pattern area 62. The first and second wheels are rotated in opposite directions so that each wheel propels the scale removing media from the lateral edge of the sheet toward the center of the sheet.
As shown in Figure 4 and 5, the blast pattern areaS 60,62 overlap in the centerline of the sheet. The impeller wheels may rotate such that the scale removing media is propelled against the lateral side edges of sheet and towards the center of the sheet. For instance, as shown in Figure 5, the first wheel rotates in a clockwise direction so as to propel the scale removing media against an outer width edge of the sheet and then toward the center of the sheet. The second wheel rotates in the counterclockwise direction so as to propel the scale removing media toward the opposite, outer width edge of the sheet and then toward the center of the sheet. Figure 5 shows a front elevation view of the impellers and the actuator for the nozzle. The same general arrangement is shown in Figure 6-11.
The edge sensors 24a,24e and the center sensor 24c are provided to detect a surface condition of the sheet 26 after the scale removing medium has been propelled against the surface of the sheet by the first and second wheels 42. As described previously, the center sensor 24c is configured to detect the surface condition of the surface of the sheet in a center of the width of the sheet. The edge sensor 24a is configured to detect the surface condition of the sheet metal adjacent to one side edge. The other edge sensor 24e is configured to detect the surface condition of the sheet adjacent to the opposite side edge. Intermediate sensors may be disposed between the center and edge sensor to provide further input to the control 20 and processor 22. The control is configured to: (a) receive signals indicative of a surface condition of the sheet as detected by the respective sensors, (b) compare the signals received from the center sensor with each of the signals received from the first and second edge sensors, and (c) transmit positional control signals to each of the nozzle actuators to rotate the respective nozzle relative to the wheel based upon the comparison of the signal of center signal with the signal of at least one of the first and second edge sensors. In wide width material for instance as shown in Figures 4-7, the intermediate sensors 24b,24d may provide signals to the control for further comparison to ensure the surface condition is uniform across the width of the sheet, or the intermediate sensors 24b,24d may be disabled from providing input to the control. In addition to or in the alternative, for instance, in the case of narrow width material as shown in Figures 8-11, the intermediate sensors 24b,24d may be used as edge sensors. For narrow width material, the intermediate sensors 24b,24d may be located to coincide with the lateral width edges of narrow width sheets, for instance, as shown in Figures 8-11. In such a configuration, the edge sensors 24a,24e may be disabled from providing input to the control.
The sensors may be used to provide input to the control for changing the location of the intensity of the spray 64,66 within the blast pattern areas 60,62 and/or changing the rate of advancement of the sheet through the descaler. Figure 12 shows one embodiment of a process flow for the controller. In one aspect, the sensors may provide input to the control to allow a determination that the surface condition of the processed sheet is consistent across a length. A length standard and length variation threshold may be established. If the comparison of the signal of the center sensor with the length standard is within the length variation threshold (e.g., indicating that the surface condition of the center of the sheet is substantially within specified limits along the length of the sheet ("condition L"), the control may be configured to send signals to the processing line controls (e.g., the PLC associated with the recoiler, or the PLC associated with tensioning rollers in the line) to take no action and maintain the rate of advancement of the sheet. If the comparison of the signal of the center sensor with the length standard indicates that the surface condition of the sheet is more favorable than the length standard (e.g., indicating that the surface condition of the center of the sheet is better than the specified limits), the control may be configured to send signals to the processing line controls to increase the rate of advancement of the sheet until condition L is met. If the comparison of the signal of the center sensor with the length standard indicates that the surface condition of the sheet is less favorable than the length standard (e.g., indicating that the surface condition of the center of the sheet is less than the specified limits), the control may be configured to send signals to the processing line controls to decrease the rate of advancement of the sheet until condition L is met. While the foregoing description uses the signal of the center sensor as a reference, the signals from other sensors may be used, and may be averaged, combined, or otherwise processed in the control to control the rate of advancement of the sheet.
In another aspect, the sensors may provide input to the control to allow a determination that the surface condition of the processed sheet is consistent across the width. A width variation threshold may be established. If the comparison of the signals of the edge sensors with the signal of the center sensor is within the width variation threshold (e.g., indicating that the surface condition of the edges of the sheet is substantially the same as the surface condition of the center of the sheet, or within the allowable width variation threshold), the control may be configured to send signals to the nozzle actuator to take no action and maintain the current position of the nozzle relative to its respective wheels, thereby maintaining the location of the intensity of the spray in the blast pattern area. If the comparison of the edge sensor signals with the center sensor signals shows that the condition of the sheet in the center is more favorable than the condition of the sheet on a lateral side outside of the allowable width variation threshold, the control generates a signal to the nozzle actuator to reposition the nozzle within the impeller to shift the location of the intensity of the spray of the blast pattern area laterally outward relative to the sheet, for instance, away from the centerline of the sheet. If the comparison of the edge sensor signals with the center sensor signals shows that the condition of the sheet in the center is less favorable than the condition of the sheet on a lateral side outside of the allowable width variation threshold, the control generates a signal to the nozzle actuator to reposition the nozzle within the impeller to shift the location of the intensity of the spray of the blast pattern area laterally inward relative to the sheet, for instance, toward the centerline of the sheet. The control may be configured to send signals to control to each nozzle actuator and position each nozzle actuator independently of the other nozzle depending upon the signal generated by the respective sensor. In this way, in the event the surface condition of one lateral edge of the sheet varies from the surface condition of the other lateral edge of the sheet, the control may send signals to the respective nozzle actuator to reposition the nozzle for the impeller wheel for the effected side of the sheet, as needed. As mentioned previously, depending upon the width of the sheet, the intermediate sensors may be disable or provide signals that may be averaged, combined, or otherwise processed in the control to control the position of the nozzle actuator and the corresponding location of the intensity of the spray within the blast pattern area.
The control may be configured to send signals to the nozzle actuator 36 to initially adjust the nozzle relative to the impeller wheel 42 to provide a set blast pattern area 60,62 across the width of the sheet based upon the size of the material being processed. For instance, as shown in Figure 13, if the width of the material is 72 inches, the nozzle position relative to the impeller 42 will may be set at an angle 68 of about five degrees relative to a reference home position H. Once descaling operations begin, the control 20 may begin processing to determine whether the processed sheet has a surface condition consistent along its length and consistent along its width. The control 20 may send signals to the nozzle actuator 36 to rotate the nozzle 40 relative to the impeller wheel in direction 70 laterally inward toward the centerline of the sheet from the 5 degree off home position H, if the comparison of the signals from the edge sensor and the center sensor indicates that the surface condition on the lateral edges of the sheet is more favorable than the surface condition of the center of the sheet. In an opposite fashion, the control 20 may send signals to the nozzle actuator 36 to rotate the nozzle 40 relative to the impeller wheel 42 in direction 72 laterally outward away from the centerline of the sheet from the 5 degree off home position H, if the comparison of the signals from the edge sensor and the center sensor indicates that the surface condition on the lateral edges of the sheet is less favorable than the surface condition of the center of the sheet. In another example, if the sheet metal to be processed has a width of 48 inches, the control 20 may send signals to the nozzle actuator 36 to set the initial nozzle position 40 relative to the impeller at an angle 38 of about 15 degrees relative to a reference home position H. Once descaling operations begin, the control 20 may begin processing to determine whether the processed sheet has a surface condition consistent along its length and consistent along its width. The control 20 may send signals to the nozzle actuator 36 to rotate the nozzle 40 relative to the impeller wheel 42 in direction 70 laterally inward toward the centerline of the sheet from the 15 degree off home position H, if the comparison of the signals from the edge sensor and the center sensor indicates that the surface condition on the lateral edges of the sheet is more favorable than the surface condition of the center of the sheet. In an opposite fashion, the control 20 may send signals to the nozzle actuator 36 to rotate the nozzle relative to the impeller wheel in direction 72 laterally outward away from the centerline of the sheet from the 15 degree off home position H if the comparison of the signals from the edge sensor and the center sensor indicates that the surface condition on the lateral edges of the sheet is less favorable than the surface condition of the center of the sheet.
As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto.

Claims

An apparatus that removes scale from sheet metal, the apparatus comprising:
a descaler that receives lengths of sheet metal (26) and removes scale from at least one surface of the length of sheet metal as the length of sheet metal (26) is moved in a first direction through the descaler;

a supply (44) of a scale medium communicating with the descaler and supplying the scale removing medium communicating the with descaler and supplying the scale removing medium to the descaler via first and second nozzles (40), the first and second nozzles each having an actuator (36) configured to rotate the respective nozzle;

first and second wheels (42) on the descaler positioned adjacent the at least one surface of the length of sheet metal (26) passed through the descaler, each of the first and second wheels (42) being configured to receive the scale removing medium from the supply (44) of scale removing medium via the rotatable nozzles, the first wheel having an axis of rotation different from the second wheel (42), rotation of the first wheel causing the scale removing medium received by the first wheel via the first nozzle to be propelled from the first wheel against the at least one surface across substantially an entire width of the sheet metal and rotation of the second wheel causing the scale removing medium received by the second wheel via the second nozzle to be propelled from the second wheel against the at least one surface across substantially an entire width of the sheet metal, the second wheel being spaced from the first wheel along the first direction a distance sufficient such that the scale removing medium propelled from the second wheel does not substantially interfere with the scale removing medium propelled from the first wheel, the first wheel and the second wheel being positioned adjacent opposite side edges defining the width of the sheet metal with the sheet metal centered between the first wheel and the second wheel; and

a control system (2) in communication with the actuators (36) of the first and second nozzles, the control being configured to:
(a) Receive signals indicative of a surface condition of the at least one surface of the sheet metal as detected by the respective sensor,
characterised in that the control system (2) is in communication with at least three sensors (24a, 24b, 24c, 24d, 24e) configured to detect a surface condition of the at least one surface of the sheet metal (26) after the scale removing medium has been propelled against the at least one surface of the sheet metal by the first and second wheels,

one of the at least three sensors comprising a center sensor (24c) configured to detect the surface condition of the at least one surface of the sheet metal in a center of the width of the sheet, two of the at least three sensors comprising edge sensors (24a, 24e), one of the edge sensors being configured to detect the surface condition of the at least one surface of the sheet metal adjacent to one side edge defining the width of the sheet metal, the other of the edge sensors being configured to detect the surface condition of the at least one surface of the sheet metal adjacent to the opposite side edge defining the width of the sheet metal,

the control being further configured to: (b) compare the signals received from the center sensor with each of the signals received from the edge sensors, and (c) transmit positioned control signals to each of the nozzle actuators to rotate the respective nozzle relative to the wheel based upon the comparison of the signal of center sensor with the signal of at least one of the edge sensors in that

when the comparison of the edge sensor signal to the center sensor signal is indicative that a surface condition of the respective edge of the at least one surface of the sheet metal is more favourable that a surface condition of the center of the at least one surface of the sheet metal, the control is configured to transmit the positioned control signal to the nozzle actuator to rotate the nozzle relative to the respective wheel in a manner such that a concentration of the scale removing medium propelled by the respective wheel against the at least one surface across substantially the entire width of the sheet metal moves toward the center of the sheet metal; and in that

when the comparison of the edge sensor signal to the center sensor signal is indicative that a surface condition of the center of the at least one surface of the sheet metal is more favourable that a surface condition of the respective edge of the at least one surface of the sheet metal, the control is configured to transmit the positioned control signal to the nozzle actuator to rotate the nozzle relative to the respective wheel in a manner such that a concentration of the scale removing medium propelled by the respective wheel against the at least one surface across substantially and entire width of the sheet metal moves away from the center of the sheet metal.
The apparatus of claim 1, wherein the control (20) is configured to transmit the positioned control signal to one nozzle actuator (36) independently of the other nozzle.
The nozzle of claim 1, wherein the scale removing medium comprises a slurry with a grit.
The apparatus of claim 1, wherein the sensor comprises a camera.
The apparatus of claim 4, wherein the signals indicative of the surface condition of the at least one surface of the sheet metal (26) comprise signals indicative of at least one of brightness, hue and saturation associated with an image of the at least one surface of the sheet metal produced by the camera.
The apparatus of claim 1, wherein the control (20) is configured to compare the signals received from the center sensor (24c) with a threshold limit and transmit a speed control signal to control a rate of advancement of the sheet metal through the descaler.
The apparatus of claim 6, wherein when the comparison of the center sensor (24c) signal to the threshold limit is indicative that a surface condition of the center of the at least surface of the sheet is more favorable than the threshold limit, the control (20) is configured to transmit the speed control signal indicative of an increase in the rate of advancement of the sheet metal (26) through the descaler.
The apparatus of claim 6, wherein when the comparison of the center sensor (24c) signal to the threshold limit is indicative that a surface condition of the center of the at least one surface of the sheet (26) is less favorable than the threshold limit, the control (20) is configured to transmit the speed control signal indicative of a decrease in the rate of advancement of the sheet metal through the descaler.
A method comprising:
advancing length of a sheet material (26) in a first direction through a descaler;

supplying a scale removing medium from a supply (44) to the descaler;

rotating first and second wheels (42) of the descaler with each of the first and second wheels receiving the scale removing medium from the supply via nozzles (40) disposed between the supply and each wheel, wherein a) rotation of the first wheel causes the scale removing medium received by the first wheel via the first nozzle to be propelled from the first wheel against the at least one surface across substantially the entire width of the sheet metal and rotation of the second wheel causes the scale removing medium received by the second wheel via the second nozzle to be propelled by the second wheel against the at least one surface across substantially an entire width of the sheet metal, b) the first wheel has an axis of rotation different from the second wheel, c) the second wheel is spaced from the first wheel along the first direction sufficient such that the scale removing medium propelled from the second wheel does not substantially interfere with the scale removing medium propelled from the first wheel, d) the first wheel and the second wheel are positioned adjacent opposite side edges defining the width of the sheet metal with the sheet metal centered between the first wheel and the second wheel; characterised by positioning the first and second nozzles relative to their respective wheels in a manner such that i) when a surface condition of the respective edges of the at least one surface of the sheet metal is more favorable than a surface condition of the center of the at least one surface of the sheet metal, the respective nozzle is positioned relative to the respective wheel in a manner such that a concentration of the scale removing medium propelled by the respective wheel against the at least one surface across substantially an entire width of the sheet metal moves toward the center of the sheet metal, and ii) when a surface condition of the center of the at least one surface of the sheet metal is more favourable than a surface condition of the respective edge of the at least one surface of the sheet metal, the respective nozzle is positioned relative to the respective wheel in a manner such that a concentration of the scale removing medium propelled by the respective wheel against the at least one surface across substantially an entire width of the sheet metal moves away from the center of the sheet metal.
The method of claim 9 further comprising:
advancing the sheet metal (26) through the descaler at a rate in a manner such that when
i) a surface condition of the center of the at least one surface of the sheet is more favourable than a threshold limit, the rate of advancement of the sheet metal through the descaler is increased; and ii) the surface condition of the center of the at least one surface of the sheet is less favourable than the threshold limit, the rate of advancement of the sheet metal through the descaler is decreased.