Devices and methods for polishing a sheet metal or metal plate leveling machine

Description

FIELD OF INVENTION

[0001] This disclosure relates generally to metal sheet or plate leveler polishers, and more specifically relates to apparatuses and methods for polishing the work rolls of a leveler.BACKGROUND OF THE INVENTION

[0002] Levelers, such as hot levelers, are commonly used in metal sheet and plate mills, namely hot rolling mills for producing metal sheets or plates. FIG. 1 illustrates a typical leveler 100 from the operator side. As shown in FIG. 1, the leveler usually includes moveable upper work rolls 60 and stationary lower work rolls 62. The metal sheet or plate enters the leveler from entry side 64 of the leveler, passes between the upper and lower working rolls, and then leaves the leveler through exit side 66. The rolling and cooling processes of the leveler reduce remaining flatness errors and residual stresses of the metal sheets or plates passing therethrough. However, as a result of passing metal sheets or plates through the rollers, under substantial compressive forces on the metal sheets or plates, particles tend to collect on the work rolls working the metal sheets or plates, which could cause gouges, pits, and scratches of the sheet and degradation in the quality of subsequently leveled plates. Thus, the polishing and cleaning of the work rolls is crucial for the effectiveness and quality of the metal sheets or plates passing through the levelers.

[0003] Conventionally, a leveler is polished by bracing the leveler in an open position, in which top portion 42 of the leveler is raised (e.g., with a roll nest support car). An operator would physically crawl into the open leveler and use a hand grinder power tool to grind-polish the work rolls. This process is potentially dangerous and inefficient, as operators could possibly be injured while polishing the work rolls. Likewise, the extent to which the work rolls are consistently and qualitatively cleaned varies from operator to operator, or upon the mechanical condition of the grinding equipment, as well as whether or not a region on the work rolls is completely accessible to the operator attempting to polish the work rolls. Uniformity in the polishing operation can vary not only relative to the accessibility of the work roll region, it can vary as a function of the amount of time and pressure invested by the operator. The lack of uniformity can affect the resulting condition of the work rolls, and, in turn, the quality of the leveled metal sheet or plate. More automated approaches have been utilized. One such technique, disclosed in Chinese Pat. No. CN205183384 calls for the use of a concave-shaped steel -bristle brush for cleaning a work roll. Alternatively, Japanese Pat. No. JP200605193 discloses the use of a cleaning member that includes an inflatable air bladder that reciprocates along the length of a work roll, while the work rolls are rotated, to clean them. US1,212,131 discloses a metal leveller with roll grinding components to allow grinding of the rolls during use. DE 296 04 532 discloses an apparatus for polishing support rollers in a metal leveller after working rolls are removed. JP H04 223 854 discloses an apparatus for polishing rollers with interchangeable polishing material. US2007 / 0180879 discloses a scraper device for continuously cleaning work rolls of a metal leveller. JP S53 91490 discloses an apparatus for grinding leveler rolls which is adapted to be installed from the housing on the operation side only when required and removed from the housing upon the termination of grinding. The present invention has as its objectives, the goal of efficiently, effectively and safely cleaning the work rolls to ensure the quality of the metal sheets or plates being processed by the leveler itself. These and other objectives and advantages will become apparent in view of the following disclosure, including the drawings and claims.SUMMARY OF THE INVENTION

[0004] The invention is defined by the independent claims. A selection of optional features is set out in the dependent claims.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The following drawings illustrate by way of example and not limitation. For the sake of brevity and clarity, every feature of a given structure is not always labeled in every figure in which that structure appears. Identical reference numbers do not necessarily indicate an identical structure. Rather, the same reference number may be used to indicate a similar feature or a feature with similar functionality, as may non-identical reference numbers. FIG. 1 shows an elevated front view of a metal sheet or plate leveler; FIG. 2 shows a perspective view of one embodiment of the present apparatus for polishing a metal sheet or plate leveler, which includes upper and lower platforms for supporting a plurality of polishers, together with the concave pans of the series of upper work roll polishers, according to various embodiments of the disclosure; FIG. 3 shows an elevated front view of the polisher apparatus of FIG. 2, sharing both series of upper and lower polishers according to various embodiments of the disclosure; FIG. 4 shows an elevated front view of the polishing apparatus in its orientation position, enabling its insertion into an open leveler, according to various embodiments of the disclosure; FIG. 5 shows an elevated front view of one embodiment of the polisher apparatus in its polishing position within the leveler, according to various embodiments of the disclosure. FIG. 6 is an elevated cross-sectional view of a polisher assembly taken along lines 6-6 of FIG. 2 and looking in the direction of the arrows; and FIG. 7 is an elevated front view of another embodiment of the polisher apparatus positioned prior to engagement of its polishers with the work rolls, in which the polisher unit relies upon a single unitary platform for supporting both its upper and lower polishers, all of which polishers can be brought into contact with all the work rolls respectively, upon lowering of the top of the leveler. DETAILED DESCRIPTION

[0006] Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. The invention is defined by the appended claims.

[0007] Generally speaking, various embodiments of the present invention provide for apparatuses and methods for safely and efficiently polishing the work rolls of a metal sheet or plate leveler for example, hot leveler 100 as shown in FIG. 1. The metal may be any metal, including but not limited to steel, aluminum or bronze. Leveler 100 is made up of top portion 42, which can be raised and lowered, and bottom portion 43, which is typically stationary.

[0008] Apparatus 200, as shown in FIG. 2, may include polishing unit 20 and stationary table support 11. Table support 11 may be positioned in front of leveler 100,) where polishing unit 20 may be moved and inserted (and / or removed) from a position between the opposing series of work rolls 45, 44 (e.g., upper work rolls 45 and lower work rolls 44) of leveler 100, from the operator side (non-driven side) of the leveler. Polishing unit 20 may include multiple polishers 22 on its top and bottom surfaces, and thus is capable of polishing a plurality of work rolls 45 of leveler 100 during the rotation of work rolls 45, while each of polishers 22 engages and polishes at least the majority of the operable length of a corresponding work roll of the leveler. Further, the polishing unit may include one or more internal expandable elements, such as air bags 28, between upper and lower platforms 24, 26 of polishing unit 20 (as shown in FIG. 3), to allow polishing unit 20 to be expanded within leveler 100, thereby causing polishers 22 (e.g., the abrasive material within the pans) to contact and polish the rotating work rolls 60, 62. In some embodiments, the polishing unit simultaneously contacts and polishes, or just polishes, all of the upper and / or lower work rolls during the polishing process, as shown in FIG. 5. After the polishing process, the expandable element may be retracted, to reorient platform 24 proximate to platform 26, to enable polishing unit 20 and, if desired, apparatus 200 in its entirety, to be removed from proximity with the leveler.

[0009] FIG. 2 illustrates polishing apparatus 200 in accordance with various other embodiments of the present invention. Apparatus 200 includes apparatus table 11 with support leg 10. Stationary apparatus table 11 balances and supports polishing unit 20 movably positioned thereon, to enable polishing unit 20 to reciprocate into and out of leveler 100 while leveler 100 is in its open position. A user may operate and control the movement of polishing unit 20 relative to table 11, optionally by motor 12 (such as an air motor), with its controls and valves 12(a) thereby moving polishing unit 20 into and out of a leveler 100. Further, polishing unit 20 may include one or more polishers 22, on each of its top and bottom platforms 24, 26. Each polisher 22 is shaped and sized to align with, engage and receive corresponding work roll 60, 62 of leveler 100. As shown in FIG. 2, polishers 22 comprise substantially rigid concave pans 22(a), each supporting an abrasive surface or abrasive lining 22(b), or a combination of a firm rubber backing 22(b) and an abrasive paper 22(c), as shown in FIG. 6. As such, during the polishing process, multiple work rolls of the leveler may simultaneously be polished by abrasive surfaces.

[0010] FIG. 3 shows a side view of polishing unit 20, to illustrate the structures and components of this embodiment in more detail. Specifically, platforms 24 and 26 are shown in their retracted orientation position in FIG. 3. In this embodiment, upper polishers 22 on platform 24 are configured to be extended away from the lower polishers 22 on lower platform 26. The juxtapositioning of the two platforms making up polishing unit 20 enables polishing unit 20 to be inserted between the upper and lower work rolls within leveler 100; once the series of upper work rolls 45 in movable leveler top portion 42 have been retracted away from the stationary series of leveler lower work rolls 44 in stationary leveler bottom 43, as the leveler assumes its open position shown in FIG. 1.

[0011] Also shown in FIG. 3 are air bags 28 for extending platform 26 away from platform 24, upon activation of the air bags, such as also by air motor 12 and air motor control 12(a), shown in FIG. 2, or by a separate air motor. The shape of the concave pans making up polishers 22 is shown in FIG. 3, together with the abrasive linings 22(a) in each such pan. A close-up of the polisher structure is shown in FIG. 6. As shown in phantom in FIG. 3, as an alternative to air motor 12, an electric motor 47, together with motor control 47(a), can be utilized to extend upper platform 24 apart from lower platform 26 to engage work rolls 60, 62 with respective polishers, when the work rolls are in their open position, through electric motor 47 and the rotation of motor gearing 48, also shown in phantom. Platform lock lever 30 is also shown in FIG. 3, together with polishing unit 20 locating lock pins 32 - which enable the alignment of the polishers 22 with respective ones of work rolls 60, 62, through cooperation of pins 32 with apertures in top portion 42 of leveler 100. As shown in FIGS. 4 and 5, locating lock pins 32 specifically cooperate with aligned apertures in leveler top 42 to maintain the polishers in alignment with their respective work rolls, both immediately prior to and during the polishing operation.

[0012] As shown in FIG. 4, polishing unit 20 includes upper platform 24 and lower platform 26, where polishers 22 are positioned on the top surface of upper platform 24 and on the bottom surface of lower platform 26. In the illustrated embodiment, upper platform 24 includes five concave polishers, and lower platform 26 includes six concave polishers, such that each polisher 22 corresponds to one of the eleven work rolls 60, 62 of leveler 100 from FIG. 1. Polishing unit 20 may also include one or more expandable elements 28 positioned between upper portion 24 and lower portion 26. Expansion and retraction may be orchestrated by expandable air bag 28, by hydraulic or pneumatic pistons, or by electric motor 47, or the like. When apparatus 200 is in use, expandable element 28 causes polishers 22 to contact and polish rotating work rolls 60, 62. When apparatus 200 is not in use, it is desirable to retract expandable element 28, so as to bring upper platform 24 and lower platform 26 closer together. Polishing unit 20 may include rollers and levers 30 to hold the upper and lower portions together when apparatus 200 is not in use.

[0013] FIGS. 4-5 illustrate polishing unit 200 inserted in leveler 100. Polishing unit 200 is inserted from the operator side of leveler 100 (e.g., towards the longitudinal direction of the work rolls). To ensure that polishing unit 200 is securely positioned within leveler 100, especially during the polishing process, locating and locking pins 32 are utilized to locate and lock polishing unit 200 into level top 42 of frame 34 of the leveler, with the respective polishers 22 and work rolls 60, 62 aligned for engagement and polishing. Entry and exit aprons 36 are placed on the entry and exit sides of leveler 100, to allow for even elevation for insertion of polishing unit 200. As shown in FIG. 4, before the polishing process, expandable elements 28 are in their contracted state (e.g., not inflated), and upper platform 24 and lower platform 26 are locked together. In the illustrated embodiment, eleven polishers 22 are positioned proximate to each of the respective eleven work rolls 60, 62 in leveler 100. As shown in FIG. 5, during the polishing process, expandable elements 28 may be extended (e.g., inflated) and adjusted. As such, the polishers in polishing unit 200 are extended to engage and contact the upper and / or lower work rolls of leveler 100, and thus polishers 22 can polish the work rolls when the work rolls commence rotation. After the polishing process, expandable elements 28 may be retracted and polishing unit 20 may then be removed from the leveler by itself, or as part of the removal of overall apparatus 200.

[0014] FIG. 6 displays the three primary layers of an embodiment of the present polishers, such as polishers 22, namely concave pan 22(a), resilient liner backing 22(b), and abrasive material layer 22(c).

[0015] In an alternative embodiment of the invention, as shown in FIG. 7, platforms 24 and 26 are integrated into one unitary platform 27, in which the upper and lower polishers 22 do not extend and retract from one another. In this embodiment, platform 27 is spring loaded relative to polishing unit 20 at spring coils 37. Engagement of polishers 22 with work rolls 60, 62 is accommodated by lowering leveler top 42 after the polisher unit has been inserted into the open leveler. In this embodiment, upper work rolls 60 in leveler top 42 engage and press upper polishers 22 on the top of platform 27, and, in turn, lower polishers 22 on the bottom of platform 27 into aligned engaged contact with lower work rolls 62 in leveler bottom 43. In this embodiment, the abrasive material 22(c), or resilient backing 22 (b) within the substantially rigid tray 22(a) of polisher 22 are thicker or otherwise more resilient, to accommodate the force which leveler top translates downwardly, to provide a tolerable range of polisher-on-work-roll pressures.

[0016] As an exemplary operating process, a user may first check the leveler and make sure that it is prepared and ready to be polished. For instance, the user should verify that all metal sheets or plates have passed the hot leveler onto the cooling bed, and should turn off cooling water to leveler rolls. Next, the user will configure the leveler into its fully open position before inserting the polishing unit. The user can then insert or push the polishing unit into the leveler. After the polishing unit is inserted and aligned, the user can adjust the gap between the work rolls and begin rotating the work rolls at a desired speed. During the rotation of the work rolls, the user may then further enlarge and adjust the extendable element distance within the polishing unit (e.g., by a valve), so that the polishers sufficiently contact and polish the rotating work rolls under suitable contact pressure. For instance, in embodiments in which the expandable units are air bags, the user may inflate the air bags by using valve control 12(a) located on the operator side, while continuing to rotate the work rolls, while they engage with the polishers of the polishing unit (e.g. for about 5 minutes for each setting). During this process, the user may inspect and verify that the polishers (especially those corresponding to the entry and exit rolls) are appropriately contacting the work rolls, and adjust the pressure of the air bags according to the desired roll pressure, as well as in response to temperature and noise. After the polishing process, the user can retract the expandable element(s) of the polishing unit, while the work rolls are still rotating. Then, the user may set up the leveler in the full open position again and stop the rotation of the work rolls. Finally, the user may remove the polishing unit and / or the polishing unit and the apparatus as a whole, from out of the open leveler, and / or the vicinity of the leveler.

Claims

1. An apparatus (200) for polishing the work rolls (60, 62) of a metal leveler, (100) each said work roll (60, 62) having a work roll circumference and a work roll length, the leveler (100) having a frame (34), a series of upper work rolls (60) and a series of lower work rolls (62), said apparatus (200) comprising: - one or more polishing units (20) sized, shaped and configured to be removably inserted between the series of upper work rolls (60) and the series of lower work rolls (62) of the leveler (100) at a location between the series of upper work rolls (60) and the series of lower work rolls (62), said polishing unit (20) comprising at least one polisher (22) configured for engaging and polishing at least one of said series of upper and lower work rolls (60, 62) of the leveler (100) during the rotation of said work roll, - said at least one polisher (22) including a substantially rigid concave pan (22(a)) having an abrasive material (22(c)) positioned therewithin for exposure of said abrasive material (22(c)) to said respective work roll upon engagement of said polisher (22) with said respective work roll and upon rotation of said work roll by said leveler within said substantially rigid concave pan (22(a)); the apparatus (200) being characterized in that said at least one polisher (22) is configured to engage and polish at least the substantial length of a corresponding one of said work rolls (60, 62) of the leveler (100) as said work roll is rotated, without repositioning said polisher (22) along the longitudinal axis of said work roll.

2. The apparatus (200) according to claim 1 in which said at least one polishing unit (20) comprises at least two polishers (22), a first polisher (22) configured for engaging at least one work roll of the upper series of work rolls (60) and a second polisher (22) configured for engaging at least one work roll of the lower series of work rolls (62) - said first and second polishers (22) configured to polish said respective upper and lower work rolls (60, 62) simultaneously as each respective work roll rotates while in engagement with each said first and second polishers (22).

3. The apparatus (200) according to claim 1 in which said at least one polishing unit (20) comprises a first series of polishers (22) corresponding in number to the number of work rolls in said series of upper work rolls (60) and a second series of polishers (22) corresponding in number to the number of work rolls in said series of lower work rolls (62) - said first series of polishers (22) configured to simultaneously engage each of said work rolls in said series of upper work rolls (60) respectively, - said second series of polishers (22) configured to simultaneously engage each of said work rolls in said series of lower work rolls (62) respectively, - all of said first and second series of polishers (22) operably configured to polish said respective series of upper and lower work rolls (60, 62) as all of said work rolls (60, 62) rotate while engaged with said first and second series of polishers (22).

4. The apparatus (200) according to claim 3, wherein all of said series of upper polishers (22) are operably positioned on an upper platform (24), and all of said series of lower polishers (22) are operably positioned on a lower platform (26), the polishers (22) on said upper platform (24) being exposed for polishing the lower circumferential surfaces of said series of upper work rolls (60) and the polishers (22) in said lower platform (26) being exposed for polishing the upper circumferential surfaces of said series of lower work rolls (62).

5. The apparatus (200 according to claim 4 in which the upper and lower platforms (24, 26), together with said first and second series of polishers (22) respectively, are selectively moveable relative to each other, - said upper and lower platforms (24, 26) being capable of being repositionable from an orientation position in which the upper and lower platforms (24, 26) are substantially adjacent each other to permit both the alternative introduction and retraction of the apparatus (200) into and from a position between said respective series of upper and lower work rolls (60, 62), to a polishing position in which said upper and lower platforms (24, 26) are extended to reposition said respective first and second series of polishers (22) into operable engagement with said series of upper and lower work rolls (60, 62), to enable the polishing of said work rolls (60, 62) upon their simultaneous rotation.

6. The apparatus (200) according to claim 4 in which the upper and lower platforms (24, 26) are integrated into a unitary platform, with the positions of said first and second series of polishers (22) respectively, being substantially fixed relative to each other, - each of said series of upper polishers (22) within said unitary platform configured for engagement with said series of upper work rolls (60) upon movement of said series of upper work rolls (60) downwardly, toward contact between the lower circumferential portions of said upper work rolls (60) and the abrasive material (22(c)) within each of the concave pans (22(a)) positioned within the polishers (22) of the upper platform (24), - said unitary platform mounted within said polishing unit (20) being springedly lowered towards the collective position of said lower work rolls (62) as said upper work rolls (60) continue to be moved downwardly, - each of said series of lower polishers (22) within said lower platform (26) configured for engagement with said series of lower work rolls (62) upon the continued movement of said series of upper work rolls (60) downwardly, toward establishing operable contact between the upper circumferential portions of said lower work rolls (62) and the abrasive material (22(c)) within each of the concave pans (22(a)) positioned within the series of lower polishers (22) oriented along the lower surface of the unitary platform.

7. The apparatus (200) according to claim 1 in which said substantially rigid concave pan (22(a)) of said at least one polisher (22) comprises a metallic pan assembly, - said abrasive material (22(c)) comprising a substantially abrasive surface positioned within said pan (22(a)) as a lining that is positioned for engagement with said respective one of said work rolls (60, 62), - wherein the abrasive surface of the lining comprises an abrasive paper having a firm rubber backing (22(b)).

8. The apparatus (200) according to claim 5, wherein the upper and lower platforms (24, 26) are repositionable to each other, between their orientation and polishing positions, through a platform translation element positioned therebetween the upper and lower platforms (24, 26) which enables the upper and lower platforms (24, 26) to be extended and retracted relative to each other.

9. The apparatus (20) according to claim 8, in which the translation element comprises an air bag assembly positioned between the upper and lower platforms (24, 26) of the apparatus (200).

10. The apparatus (200) according to claim 9 in which the air bag assembly includes an air motor and valve to alternatively inflate and deflate the air bag assembly to in turn extend and retract the positions of the upper and lower platforms (24, 26) respectively.

11. The apparatus (200) according to claim 5 further comprising a closing element for locking the upper and lower platforms (24, 26) together in their orientation position while the apparatus (200) is not in its polishing position.

12. The apparatus (200) according to claim 8 in which said translation element comprises an electric motor for alternatively extending and retracting the upper and lower platforms (24, 26) relative to each other.

13. A method for polishing the work rolls (60, 62) of a metal leveler (100) through the use of a polishing apparatus (200), comprising the steps of: configuring the leveler (100) in an open position; inserting said polishing apparatus (200) into the leveler (100), between the upper and lower work rolls, at a location between the upper work rolls and the lower work rolls, wherein the polishing apparatus (200) includes polishers (22) on its top and bottom surfaces for simultaneously engaging and polishing the respective work rolls (60, 62) of the leveler (100) during the rotation of the work rolls (60, 62), wherein at least one of the polishers (22) includes a substantially rigid concave pan (22(a)) having an abrasive material (22(c)) therewithin, said pan (22(a)) being configured to engage and polish at least a majority of a length of a corresponding work roll of the leveler (100); juxtaposing the polishers (22) and the upper and lower work rolls (60, 62) of the leveler (100) by extending the polishers (22) to further contact the work rolls (60, 62), during the rotation of the work rolls (60, 62), rotating the work rolls (60, 62) to polish same within the polisher pans (22(a)).