CA2351757C - Method device for winding metal strips - Google Patents
Method device for winding metal strips Download PDFInfo
- Publication number
- CA2351757C CA2351757C CA002351757A CA2351757A CA2351757C CA 2351757 C CA2351757 C CA 2351757C CA 002351757 A CA002351757 A CA 002351757A CA 2351757 A CA2351757 A CA 2351757A CA 2351757 C CA2351757 C CA 2351757C
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- CA
- Canada
- Prior art keywords
- coil
- coiling
- metal strip
- face
- step portion
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C47/00—Winding-up, coiling or winding-off metal wire, metal band or other flexible metal material characterised by features relevant to metal processing only
- B21C47/02—Winding-up or coiling
- B21C47/04—Winding-up or coiling on or in reels or drums, without using a moving guide
- B21C47/06—Winding-up or coiling on or in reels or drums, without using a moving guide with loaded rollers, bolts, or equivalent means holding the material on the reel or drum
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C47/00—Winding-up, coiling or winding-off metal wire, metal band or other flexible metal material characterised by features relevant to metal processing only
- B21C47/02—Winding-up or coiling
- B21C47/04—Winding-up or coiling on or in reels or drums, without using a moving guide
- B21C47/06—Winding-up or coiling on or in reels or drums, without using a moving guide with loaded rollers, bolts, or equivalent means holding the material on the reel or drum
- B21C47/063—Winding-up or coiling on or in reels or drums, without using a moving guide with loaded rollers, bolts, or equivalent means holding the material on the reel or drum with pressure rollers only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C47/00—Winding-up, coiling or winding-off metal wire, metal band or other flexible metal material characterised by features relevant to metal processing only
- B21C47/003—Regulation of tension or speed; Braking
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C47/00—Winding-up, coiling or winding-off metal wire, metal band or other flexible metal material characterised by features relevant to metal processing only
- B21C47/02—Winding-up or coiling
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Winding, Rewinding, Material Storage Devices (AREA)
- Replacement Of Web Rolls (AREA)
Abstract
In winding a thin metal strip at high speed, it is intended to increase the yield by preventing malformation due to the stretching of the metal strip. A method of winding metal strips, wherein before the end of the winding, wrapper rolls (6) are pressed against the outer winding surface of a coil (5) to brake the rotation of the coil (5), whereby the rotation of the coil (5) is stopped in a short time at the end of the winding, the pressing force exerted by each wrapper rolls (6) being 10-20 kN/m.
Description
METHOD DEVICE FOR WINDING METAL STRIPS
Technical Field The present invention relates to a method of and an apparatus for coiling a metal strip on a mandrel when the metal strip is rolled at high speed like in a hot rolling and, in particular, relates to a method of and an apparatus for coiling a metal strip, each of which is adapted such that wrapper rolls are pushed against an outer coiling face of coil before a coiling is finished to thereby brake the rotation of the coil and, by this, the rotation of the coil is stopped in a short time when the coiling is finished.
Background of the Invention In a hot rolling line, a hot-rolled metal strip is coiled by a coiler disposed in a downstream side of a finishing mill, thereby making a coil. Hitherto, if one material to be rolled is finish-rolled, the rolled material to be rolled is coiled by the coiler as one coil. As to an unsteady portion such as tip portion or tail portion of the material to be rolled, a shaped control or a meander control of the material to be rolled is difficult. Further, recently, thinner hot-rolled metal strip products are in brisk demand, but if the thickness of the rolled metal strip becomes thin, the shape control or the meander control becomes more difficult. Therefore, by means of increasing a weight rolled in a finishing roll in one time by increasing a weight of one material to be rolled or connecting a preceding material to be rolled and a following material to be rolled in an inlet side of the finishing mill, it is performed to make small the rate occupied by the unsteady portion.
In this case, since there is a limit in the weight capable of being coiled by the toiler in on time, several toilers are used, a strip shear is provided between the finishing mill and the toilers, the metal strip sent out from the hot finishing mill is cut in a predetermined length by the strip shear, and, thereafter, it is coiled anternately by the plural coiling devices in a coil-like form. On this occasion, in order to reduce the time period until the coiling of the metal strip by the next coiling device is started, it is necessary to stop the rotation of the coil as rapidly as possible after the coiling of the metal strip by the present coiling device has finished.
Known in the art there is an apparatus for coiling a metal strip, which responds to such a demand, disclosed in Japanese Patent Laid-Open No. 154550/1993 Gazette for instance. This apparatus, as shown in Fig. 6, is adapted such that plural wrapper rolls 6 are arranged so as to be able to approach or separate from an outer coiling face of a coil 5, the wrapper rolls 6 are approached toward the outer coiling face of the coil 5 to thereby apply a predetermined pushing force to the outer coiling face before finishing the coiling and, by this, a flutter of tail end of the coil 5 is prevented and the rotation of the coil 5 is stopped rapidly by being braked when finishing the coiling. Furthermore, when starting the coiling, the wrapper rolls 6 are disposed adjacently to a mandrel 2 of a coiling device 1 to thereby sandwich a tip of the metal strip between them and the mandrel 2 and, by this, have in combination also a function of surely performing a coiling start operation. Incidentally, it is adapted such that, after the coiling has been started, the wrapper rolls 6 are a separated from the outer coiling face of the coil 5 until a predetermined time period before the coiling is finished.
By the way, for example, in the aforesaid hot rolling method in which the preceding material to be rolled and the following material to be rolled are connected in the inlet side of the finishing mill, it is made possible to perform a thin material rolling by applying a stable tension over a whole length by means of continuously rolling one in which several tens of rolling raw materials are connected.
However, in case where a thin metal strip is coiled at high speed by using the aforesaid conventional apparatus for coiling a metal strip as shown in Fig. 7, the outer coiling face of the coil 5 is pushed by the wrapper roll 6 and, if the wrapper roll 6 impinge against a portion located in a step between an inner coiling most tip portion (metal strip tip) 5a of the coil 5 in an outer coiling face of the coil 5 and a surface of the mandrel 2 (hereafter, referred to as step portion 16), the step portion 16 is then rolled by a high pressure because the coil 5 is rotating at high speed. As a result, there is a drawback that a portion of the metal strip being coiled, located at the step portion 16 generates a shape defect, so that the process yield ratio decreases. And, it has been confirmed that this shaped defect becomes remarkable in case that a thickness is 2.3 mm or less and a coiling speed is 700 mpm or higher. Incidentally, it is frequent that the wrapper roll 6 is provided with a convex crown so that the aforesaid shape defect is mainly a center buckle.
Furthermore, there is described in Japanese Patent Laid-Open No. 126021/1981 Gazette and Japanese Patent Laid Open No. 92118/1984 Gazette, a method of buffering an impact force generated in the step portion by, in a machine for coiling a metal strip, performing an operation for raising at a coil step portion generated in a metal strip tip portion before an upper roll passes in the initial stage of coiling the metal strip on a mandrel to thereby avoid an impigement and lower the upper roll after it has passed. However, as mentioned before where the weight of one material to be rolled is large and the fact that one in which several tens of rolling raw materials are connected is continuously rolled and coiled at high speed are not assumed, there is not disclosed the fact that, when finishing the coiling, it is stopped rapidly by means of braking the coil rotation means of wrapper rolls.
Accordingly, in case that a continuous finish-rolling is performed or in a case where a large unit weight coil is rolled, since a high speed winding is performed, there is a drawback in that, in a case where there is a step portion in a coil outer coiling portion, the step portion is rolled by a high pressure and consequently this portion generates a shape defect.
The invention has been made in order to solve such a drawback, and its object is to provide a method of and an apparatus for coiling a metal strip, each of which is for improving the coiling of a metal strip such that no shape defect is generated when coiling a thin metal strip at high speed.
Disclosure of the Invention According to the present invention, there is provided a method of coiling a metal strip after a hot finish rolling adapted before the metal strip is coiled on a mandrel, plural wrapper rolls are pushed against an outer coiling face of a coil to brake a rotation of the coil, thereby stopping the rotation of the coil, characterized in that a position of a step portion appearing in an outer coiling face of the coil owing to a step between a leading end of the coil and a surface of the mandrel is detected, and a pushing force of each of the wrapper rolls is made 20 kN/m or lower only during a predetermined time before or after the step portion passes a position of each of the wrapper rolls.
Preferably, the method of coiling a metal strip is characterized in that the pushing force applied per 1 m coil width the wrapper roll on the step portion and on a portion other than the step portion is made 10 - 20 kN/m.
Preferably, the method of coiling a metal strip is characterized in that before the metal strip is finished to be coiled on the mandrel, the wrapper roll is approached from a waiting position nearer to the mandrel than an open limit toward the outer coiling face of the coil, thereby starting a pushing of the outer coiling face.
According to the present invention, there is also provided an apparatus for coiling a metal strip, having a mandrel for coiling the metal strip in a coil-like form, plural wrapper rolls for pushing an outer coiling face of a coil coiled on the mandrel, a support frame which supports each of the wrapper rolls and which is provided so as to be able to approach or separate from the outer coiling face of the coil, and drive means for causing the support frame to approach or separate from the outer coiling face of the coil, characterized by having strip shear controlling means for transmitting a coiling finish signal to a strip shear for cutting the metal strip after a hot finish rolling and to drive means for pushing each of the wrapper rolls against the outer coiling face of the coil, step portion position detecting means for detecting a position of a step portion appearing in the outer coiling face of the coil owing to a step between a leading end of the coil and a surface of the mandrel, and wrapper roll controlling means for controlling, on the basis of a detection position by the step portion position detecting means, the drive means such that a gap between the wrapper roll and the outer coiling face or a pushing force of the outer coiling face by each of the wrapper rolls is changed.
Preferably, the apparatus is characterized in that the step portion position detecting means has means for detecting, when starting to coil the metal strip, a position of a tip of the metal strip coiled on the mandrel, means for operating the tip position as a rotation angle 8 with respect to a predetermined position of the mandrel, means for storing the rotation angle 8, and means for operating, before the metal strip is finished to be coiled, the rotation angle 8 position of the step portion appearing in the outer coiling face of the coil.
Preferably, the apparatus for coiling a metal strip is characterized in that the rotation angle 8 is found by a sensor for detecting the fact that the metal strip tip has passed, a tachometer for detecting a rotating speed of the coil, and a sheet speed detecting sensor.
Preferably, the method of coiling a metal strip is characterized in that in case that a rotating speed of the coil is reduced to lower than a predetermined rotating speed, the pushing force of the wrapper roll is set so as to exceed 20 kN/m.
Brief Description of the Drawings Fig. 1 is a schematic view of an apparatus for coiling a metal strip, which is one example of 1st embodiment of the invention.
Fig. 2 is an explanatory view of the 1st embodiment of the invention which explains a relative operation of a wrapper roll with respect to a coil outer winding face in a coiling finish stage.
Fig. 3 is an explanatory view of the 1st embodiment of the invention, for explaining the relative operation of the wrapper roll with respect to the coil outer winding face in a pushing start time.
Fig. 4 is an explanatory view of 2nd embodiment of the invention, which explains the relative operation of the wrapper roll with respect to the coil outer winding face in the coiling finish stage.
Fig. 5 is an explanatory view of a 3rd embodiment of the invention, which explains the relative operation of the wrapper roll with respect to the oil outer winding face in the coiling finish stage.
Fig. 6 is a schematic view for explaining a conventional apparatus for coiling a metal strip.
Fig. 7 is an explanatory view for explaining a step portion appearing in an outer coiling face of a coil owing to a step between a leading end of the coil and a mandrel surface.
Hereunder, embodiments of the invention are explained by referring Fig. 1 - Fig. 5.
First, in explaining a 1st embodiment of the invention by referring to Fig. 1 - Fig. 3, in Fig. 1, the reference numeral 2 denotes a mandrel for coiling, through a pinch roll 4 , a metal strip 3 cut in a predetermined length by a strip shear (reference numeral 22 in Fig. &) after passing through a hot finishing mill (reference numeral 21 in Fig. 6) in a coil-like form, and plural wrapper rolls (four places in Fig. 1) 6 are arranged in a peripheral direction with a predetermined ' spacing in an outer coiling face side of a coil 5 coiled on the mandrel 2.
Each wrapper roll 6 is respectively supported by a support frame (only one place is shown in Fig. 1) 7 provided so as to be rotatable through a rotation supporting point Ta in a direction approaching or separating from an outer coiling face of the coil 5, and a piston rod 8a of a hydraulic cylinder (drive means) 8 is connected to the support frame 7. It is adapted such that, by extending the piston rod 8a, the support frame 7 is rotated in the direction approaching the outer coiling face of the coil 5 and thus the wrapper roll 6 contacts with the outer coiling face and, by retracting it, the support frame 7 is rotated in the direction separating from the outer coiling face of the coil 5 and thus the wrapper roll 6 separates from the outer coiling face.
Further, between the coil 5 and the pinch roll 4, there is arranged a laser sensor 9 for detecting the fact that a tip of the metal strip 3 has passed, a detection sensor 10 for detecting a rotating speed and a rotation angle of the coil is attached to the mandrel 2 , a sheet speed detecting sensor 11 for detecting a carrying speed (sheet speed) of the metal strip 3 is attached to the pinch roll 4, a rotation angle detecting sensor 12 for detecting a rotation angle is attached to the support frame 7, and pressure detecting sensors 13a, 13b for detecting a working pressure are attached to the hydraulic cylinder 8. And, it is adapted such that, on the basis o~f a signal from each sensor, a controller 14 controls the hydraulic cylinder 8 through a drive circuit 15.
The controller 14 has an operation section 17 for operating, on the basis of the signals from the laser sensor 9 , the rotating speed sensor 10 and the sheet speed detecting sensor 11, an inner coiling most tip portion 5a of the coil as a rotation angle 8 from a predetermined position of the mandrel, a tip step portion storing section 19 for storing the A, the operation section 17 for operating,' on the basis of a signal from a strip shear controlling section 20 before finishing the coiling of the metal strip, the 8 as a position of a step portion 16 appearing in the outer coiling face of the coil 5 owing to a step between the coil and a surface of the mandrel 2, and a control section (control means)18 for performing a position control and a pushing force control of the wrapper roll 6 with respect to the outer coiling face of the coil 5 by controlling the hydraulic cylinder 8 through the drive circuit 15. Here, in this embodiment, step portion position detecting means of the invention is constituted by the laser sensor 9, the rotating speed detecting sensor 10, the sheet speed detecting sensor 11, the operation section 17 , the tip step portion storing section 19 and the strip shear controlling section 20, but it may be adapted such that the position of the step portion 16 is detected by another publicly known detecting means or tracking means and the like.
The control section 18 is adapted so as to control the hydraulic cylinder 8 in a coiling start stage and a coiling finish stage. In the coiling start stage, in order to surely perform a coiling start operation, the piston rod 8a of the hydraulic cylinder 8 is extended synchronizing with a coiling start timing of a tip of the metal strip 3 , which is obtained on the basis of the signal from the laser sensor 9 and, by this , the support frame 7 is rotated by a predetermined angle in the direction approaching an outer face of the mandrel 2, thereby sandwiching the tip of the metal strip 3 between the wrapper roll 6 and the mandrel 2. Further, after a predetermined time has elapsed from the coiling start, the support frame 7 is rotated by a predetermined angle in the direction separating from the outer coiling face of the coil 5 by retracting the piston rod 8a and, by this, the wrapper roll 6 is caused to wait at a predetermined position by being shunted from the outer coiling face of the coil 5 until a predetermined time before the coiling is finished.
Incidentally, an extension/retraction amount of the piston rod 8a of the hydraulic cylinder 8 in this case is controlled such that a detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle (this is stored in a storage area of the control section 18) of the support frame 7, which is previously set in compliance with a sandwiching position of the metal strip 3 tip and a shunting position at the wrapper roll 6. Further, at the coiling start time, the aforesaid step portion 16 appears in the coil 5 outer coiling face between the wrapper roll 6 and the mandrel 2 correspondingly to the step between the most tip portion (metal strip tip) 5a of the metal strip 3 and the surface of the mandrel 2.
On the other hand, in the coiling finish stage, on the basis of a tail end wrapper roll pushing start signal from the strip shear controlling unit 20, first, when starting a pushing by the wrapper roll 6 against the coil 5 outer coiling face, it is judged whether or not the position 8, of the metal strip tip portion, operated by the operation section 17 on the basis of the signals from the laser sensor 9, the rotating speed detecting sensor 10 and the sheet speed detecting sensor 11 agrees with a contact position, stored in the storing section 19, of the wrapper roll 6 with respect to the coil 5 outer coiling face. In case that it does not agree with, the piston rod 8a of the hydraulic cylinder 8 is extended synchronizing with a previously set pushing start timing in order to~brake the rotation of the coil 5 to stop it in a short time and, by this , the support frame 7 is rotated by a predetermined angle in the direction approaching the outer coiling face of the coil , thereby bringing the wrapper roll 6 into contact with the coil 5 outer coiling face.
In case that a position of the step portion 16 agrees with a contact start position of the wrapper roll 6 , as shown in Fig. 3, the piston rod 8a of the hydraulic cylinder 8 is retracted before a predetermined time at which the step portion 16 reaches the contact start position of the wrapper roll 6 in order to avoid the contact and, by this, the support frame 7 is rotated by a predetermined angle in the direction separating from the outer coiling face of the coil 5 to thereby shunt the wrapper roll 6 from the coil 5 outer coiling and, after a predetermined time has elapsed from when the position of the step portion 16 has passed a contact position of the wrapper roll 6, the piston rod 8a of the hydraulic cylinder 8 is extended and, by this, the support frame 7 is rotated by a predetermined angle in the direction approaching the outer coiling face of the coil 5, thereby bringing the wrapper roll 6 into contact with the coil 5 outer coiling face.
Incidentally, an extension/retraction amount of the piston rod 8a of the hydraulic cylinder 8 in this case is controlled such that a detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle (this is stored in a storage area of the control section 18 ) of the support frame 7, which is previously set in compliance with a contact position and a shunting position with respect to the outer coiling face of the coil 5 at the wrapper roll 6.
After the wrapper roll 6 has contacted with the outer coiling face of the coil 5, the hydraulic cylinder 8 is controlled such that a detection pressure obtained from the pressure detecting sensors 13a, 13b agrees with a previously set working pressure for applying a predetermined pushing force to the outer coiling face of the coil 5. Here, a pushing force per a lm coil width of the wrapper roll 6 with respect to the outer coiling face of the coil 5 is made a range of 10 - 20 kN/m. If the pushing force is lower than 20 kN/m, a braking force necessary for a rotation of the coil is not obtained and, further, it is impossible to suppress a bulge of coil outer periphery portion owing to a centrifugal force at high speed rotation time. On the other hand, if it exceeds 20 kN/m, a high pressure is generated when the wrapper roll 6 impinges against the step portion 16 of the coil 5 rotating at high speed, so that a center buckle occurs in the coil 5.
Next, it is explained about an actuation of the control section 18.
First, in the coiling start stage, the piston rod 8a of the hydraulic cylinder 8 is extended synchronizing with the coiling start timing of the tip of the metal strip 3, which is obtained on the basis of the signal from the laser sensor 9 , such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7, previously set in compliance with a sandwiching position of the metal strip 3 tip at the wrapper roll 6 , thereby rotating the support frame 7 in the direction approaching the outer face of the mandrel 2 and, by this, the tip of the metal strip 3 is sandwiched between the wrapper roll 6 and the mandrel 2, thereby surely performing a coiling start operation.
Further, after a predetermined time has elapsed from the coiling start, the piston rod 8a is retracted such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7, previously set in compliance with a shunting position of the wrapper roll 6, thereby rotating the support frame 7 in the direction separating from the outer coiling face of the coil and, by this, the wrapper roll 6 is shunted from the outer coiling face of the coil 5 until a predetermined time before the coiling is finished, thereby causing it to wait in a predetermined position. Incidentally, as to this waiting position, it is advantageous to locate it as nearly to the mandrel as possible than a open limit of the wrapper roll, because an operation for pushing the wrapper roll at a coiling finish time can be rapidly performed.
In the coiling finish stage, first, when starting the pushing by the wrapper roll 6 against the coil 5 outer coiling face, it is judged whether or not the position of the step portion 16 agrees with the contact position of the wrapper roll 6. In case that it does not agree with, the piston rod 8a of the hydraulic cylinder 8 is extended synchronizing with the previously set pushing start timing such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7 , previously set in compliance with the contact position with respect to the outer coiling face of the coil 5 at the wrapper roll 6 in order to brake the rotation of the coil 5 to stop it in a short time and, by this , the support frame 7 is rotated in the direction approaching the outer coiling face of the coil 5, thereby bringing the wrapper roll 6 into contact with the coil 5 outer coiling face.
In case that the position of the step portion 16 agrees with the contact position of the wrapper roll 6, as shown in Fig. 3, the piston rod 8a of the hydraulic cylinder 8 is retracted before the predetermined time at which the position of the step portion 16 reaches the contact position of the wrapper roll 6 such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7 , previously set in compliance with the shunting position with respect to the coil 5 outer coiling face of the wrapper roll 6 in order to avoid the contact and, by this, the support frame 7 is rotated in the direction separating from the outer coiling face of the coil 5 to thereby shunt the wrapper roll 6 from the coil 5 outer coiling and, after the predetermined time has elapsed from when the position of the step portion 16 has passed the contact position of the wrapper roll 6 , the piston rod 8a of the hydraulic cylinder 8 is extended such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7, previously set in compliance with the contact position with respect to the coil 5 outer coiling face of the wrapper roll 6 and, by this, the support frame 7 is rotated by in the direction approaching the outer coiling face of the coil 5, thereby bringing the wrapper roll 6 into contact with the coil outer coiling face.
After the wrapper roll 6 has contacted with the outer coiling face of the coil 5, the hydraulic cylinder 8 is controlled such that the detection pressure obtained from the pressure detecting sensors 13a, 13b can obtain a previously set braking force necessary for the rotation of the coil 5 and agrees with a working pressure for giving a pushing pressure - 20 kN/ m per a coil width 1 m, under which no shape defect occurs even if the wrapper coil 6 impinges against the step portion 16 of the coil 5 rotating at high speed, to the outer coiling face of the coil 5, the outer coiling face of the coil 5 is continued to be pushed by this pushing force until the coil 5 is speed-reduced to a predetermined rotating speed (speed at which no shape defect occurs in the step portion 16 even if the wrapper roll 6 pushed by the pushing force exceeding 20 kN/m impinges against the step portion 16 of the rotating coil 5: lower than 700 mpm), and, after it has been speed-reduced to the predetermined rotating speed, the pushing force is increased to exceed 20 kN/rn, thereby increasing a rotation braking force of the coil 5.
As apparent from the above explanations, according to this embodiment, in the coiling finish stage, since it is adapted such that the braking force necessary for the rotation of the coil 5 is obtained and the outer coiling face of the coil 5 is pushed by the pushing force under which no shape defect occurs even if the wrapper coil 6 impinges against the step portion 16 of the coil 5 rotating at high speed, it is possible to adapt such that no shape defect occurs in the metal strip existing in a step portion 16 position after a thin (2.3 mm or less) metal strip is coiled at high speed (700 mpm or higher) as the coil and, as a result, it is possible to increase a process yield ratio.
Further, at a pushing start time of the coil 5 outer face by the wrapper roll 6, since it is adapted such that the wrapper roll 6 does not contact with the step portion 16, the impingement between the wrapper roll 6 and the step portion 16 of the coil 5 rotating at high speed is avoided at the pushing start time, so that an occurrence of the shape defect can be surely prevented.
Incidentally, in the aforesaid embodiment, as an example there is adopted a case in which the invention is applied when coiling the metal strip 3 cut in a predetermined length by the strip shear into a coil-like form, but it is needless to say that the invention may be applied to an ordinary batch rolling.
Further, as shown in Fig. 2, the wrapper roll may be always pushed by a constant pressure irrespective of whether or not the step portion 16 exists by means of controlling the hydraulic cylinder 8 so as to agree with a working pressure for giving the pushing force 10 - 20 kN/m to the outer coiling face of the coil 5. It is also possible that the outer coiling face of the coil 5 is continued to be pushed by this pushing force until the coil 5 is speed-reduced to the predetermined rotating speed as mentioned before and, after it is speed-reduced to the predetermined rotating speed (lower than 700 mpm), the pushing force is increased to enhance a rotation braking force of the coil 5.
Next, it is explained about a method of coiling a metal strip, which is an embodiment of a 2nd mode of the invention, by referring to Fig. 1 and Fig. 4. Incidentally, this coiling method differs with respect to the aforesaid coiling device 1 only in a controlling method of the hydraulic cylinder 8 by the control section 18 of the controller 14 after the wrapper roll 6 has contacted with the outer coiling face of the coil in the coiling finish stage.
After the wrapper roll 6 has contacted with the outer coiling face of the coil 5 in the coiling finish stage, the control section 18 controls the hydraulic cylinder 8 such that the detection pressure obtained from the pressure detecting sensors 13a, 13b agrees with a previously set working pressure for giving a pushing force forcedly braking the rotation of the coil 5 to the outer coiling face of the coil 5 until a predetermined time before the position, of the step portion 16, operated by the operation section 17 on the basis of the signals from the laser sensor 9 , the rotating speed detecting sensor 10 and the sheet speed detecting sensor 11 reaches a contact position, of the wrapper roll 6 with respect to the coil 5 outer coiling face, previously stored in the storage area (not shown) . It is preferable that the pushing force on this occasion is a large value (exceeding 20 kN/m) in order that a braking force for the rotation of the coil 5 by the wrapper roll 6 is obtained.
Further, during a time from a predetermined time at which the step portion 16 reaches the contact position of the wrapper roll 6 to a time point at which a predetermined time has elapsed after the step portion 16 has passed the contact position of the wrapper roll 6 , the hydraulic cylinder 8 is controlled such that the detection pressure obtained from the pressure detecting sensors 13a, 13b gives a weak pushing force (20 kN/m or lower) previously set such that no shape defect occurs in the step portion 16 even if the wrapper roll 6 impinges against the step portion 16 of the coil 5 rotating at high speed.
Incidentally, the control for weakening the pushing force by the wrapper roll 6 is performed until the coil 5 is speed-reduced to a predetermined rotating speed (speed at which no shape defect occurs in the step portion 16 even if the wrapper roll 6 pushing by a strong pushing force (exceeding 20 kN/m) impinges against the step portion 16 of the rotating coil 5:
lower than 700 mpm) and, after being speed-reduced to the predetermined rotating speed, the pushing force is increased to enhance the rotation braking force of the coil 5.
As apparent from the above explanations, in this embodiment since it is adapted such that, in the coiling finish stage, a sufficient braking force is obtained for the rotation of the coil 5 and, before and after the step portion 16 passes the contact position of the wrapper roll 6, the outer face of the coil 5 is pushed by such a weak pushing force that no shape defect occurs in the step portion 16 even if the wrapper roll 6 impinges against the step portion 16 of the coil 5 rotating at high speed, it is possible, after coiling the coil 5 of the thin (2.3 mm or less) metal strip at high speed (700 mpm or higher) , to prevent the shape defect from occurring in the metal strip and, as a result, the improvement in yield can be intended.
Incidentally, since another action/effect is the same as the embodiment of the 1st mode mentioned above, its explanation is omitted.
Next, it is explained about a method of coiling a metal strip, which is an embodiment of a 3rd mode of the invention, by referring to Fig. 1 and Fig. 5. Incidentally, also this coiling method differs with respect to the aforesaid coiling device 1 only in a controlling method of the hydraulic cylinder 8 by the control section of the controller 14 after the wrapper roll 6 has contacted with the outer coiling face of the coil in the coiling finish stage.
After the wrapper roll 6 has contacted with the outer coiling face of the coil 5 in the coiling finish stage, the control section 18 controls the hydraulic cylinder 8 such that the detection pressure obtained from the pressure detecting sensors 13a, 13b agrees with the previously set working pressure for giving the pushing force forcedly braking the rotation of the coil 5 to the outer coiling face of the coil 5 until the predetermined time before the position, of the step portion 16, operated by the operation section 17 on the basis of the signals from the laser sensor 9, the rotating speed detecting sensor 10 and the sheet speed detecting sensor 11 reaches the contact position, of the wrapper roll 6 with respect to the coil 5 outer coiling face, previously stored in the storage area (not shown).
Further, during the time from the predetermined time at which the step portion 16 reaches the contact position of the wrapper roll 6 to the time point at which the predetermined time has elapsed after the step portion 16 has passed the contact position of the wrapper roll 6, the piston rod 8a of the hydraulic cylinder 8 is retracted such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with the rotation angle, of the support frame 7, previously set in compliance with the shunting position of the wrapper roll 6 with respect to the coil 5 outer coiling face and, by this, the support frame 7 is rotated in the direction separating from the outer coiling face of the coil 5, thereby controlling the wrapper coil 6 so as to be shunted from the coil 5 outer coiling face.
Further, after a predetermined time has elapsed from a time point at which the position of the step portion 16 has passed the aforesaid contact position, the piston rod 8a of the hydraulic cylinder 8 is extended such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with the rotation angle, of the support frame 7, previously set in compliance with the contact position of the wrapper roll 6 with respect to the coil 5 outer coiling face and, by this , the support frame 7 is rotated in the direction approaching the outer coiling face of the coil 5, thereby bringing the wrapper roll 6 into contact with the coil 5 outer coiling face and, thereafter, the hydraulic cylinder 8 is rapidly controlled such that the detection pressure obtained from the pressure detecting sensors 13a, 13b agrees with a previously set working pressure for giving a pushing force forcedly braking the rotation of the coil 5 to the outer coiling face of the coil 5.
Incidentally, the control for shunting the wrapper roll 6 from the step portion 16 is performed until the coil 5 is speed-reduced to a predetermined rotating speed (speed at which no center buckle occurs in the coil 5 even if the wrapper roll 6 impinges against the step portion 16 of the rotating coil 5) and, after it has been speed-reduced to the predetermined rotating speed (lower than 700 mpm), the pushing force is increased to enhance the rotation braking force of the coil 5.
As apparent from the above explanations, in this embodiment since it is adapted such that, in the coiling finish stage, a sufficient braking force is obtained for the rotation of the coil 5 and, before and after the step portion 16 passes the contact position of the wrapper roll 6, the wrapper roll 6 does not impinge against the step portion 16 of the coil 5 rotating at high speed, it is possible, after coiling the thin (2.3 mm or less) metal strip into the coil 5 at high speed (700 mpm or higher) , to prevent the shape defect from occurring in the metal strip and, as a result, the improvement in yield can be intended. Incidentally,since another action/effect is the same as the embodiment of the 1st mode mentioned above, its explanation is omitted.
Industrial A~~licabilitv As apparent from the above explanations, according to the invention, since it is possible to adapt such that, after coiling the thin metal strip into the coil at high speed, no shape defect occurs in the coiled metal strip, there is obtained an effect that the improvement in yield can be intended.
Further, when starting to push the coil outer coiling face by the wrapper roll, since the impingement between the wrapper roll and the step portion of the coil rotating at high speed can be avoided at the pushing start time by controlling the wrapper roll so as not to contact with the step portion, there is obtained an effect that an occurrence of the shape defect can be surely prevented.
Technical Field The present invention relates to a method of and an apparatus for coiling a metal strip on a mandrel when the metal strip is rolled at high speed like in a hot rolling and, in particular, relates to a method of and an apparatus for coiling a metal strip, each of which is adapted such that wrapper rolls are pushed against an outer coiling face of coil before a coiling is finished to thereby brake the rotation of the coil and, by this, the rotation of the coil is stopped in a short time when the coiling is finished.
Background of the Invention In a hot rolling line, a hot-rolled metal strip is coiled by a coiler disposed in a downstream side of a finishing mill, thereby making a coil. Hitherto, if one material to be rolled is finish-rolled, the rolled material to be rolled is coiled by the coiler as one coil. As to an unsteady portion such as tip portion or tail portion of the material to be rolled, a shaped control or a meander control of the material to be rolled is difficult. Further, recently, thinner hot-rolled metal strip products are in brisk demand, but if the thickness of the rolled metal strip becomes thin, the shape control or the meander control becomes more difficult. Therefore, by means of increasing a weight rolled in a finishing roll in one time by increasing a weight of one material to be rolled or connecting a preceding material to be rolled and a following material to be rolled in an inlet side of the finishing mill, it is performed to make small the rate occupied by the unsteady portion.
In this case, since there is a limit in the weight capable of being coiled by the toiler in on time, several toilers are used, a strip shear is provided between the finishing mill and the toilers, the metal strip sent out from the hot finishing mill is cut in a predetermined length by the strip shear, and, thereafter, it is coiled anternately by the plural coiling devices in a coil-like form. On this occasion, in order to reduce the time period until the coiling of the metal strip by the next coiling device is started, it is necessary to stop the rotation of the coil as rapidly as possible after the coiling of the metal strip by the present coiling device has finished.
Known in the art there is an apparatus for coiling a metal strip, which responds to such a demand, disclosed in Japanese Patent Laid-Open No. 154550/1993 Gazette for instance. This apparatus, as shown in Fig. 6, is adapted such that plural wrapper rolls 6 are arranged so as to be able to approach or separate from an outer coiling face of a coil 5, the wrapper rolls 6 are approached toward the outer coiling face of the coil 5 to thereby apply a predetermined pushing force to the outer coiling face before finishing the coiling and, by this, a flutter of tail end of the coil 5 is prevented and the rotation of the coil 5 is stopped rapidly by being braked when finishing the coiling. Furthermore, when starting the coiling, the wrapper rolls 6 are disposed adjacently to a mandrel 2 of a coiling device 1 to thereby sandwich a tip of the metal strip between them and the mandrel 2 and, by this, have in combination also a function of surely performing a coiling start operation. Incidentally, it is adapted such that, after the coiling has been started, the wrapper rolls 6 are a separated from the outer coiling face of the coil 5 until a predetermined time period before the coiling is finished.
By the way, for example, in the aforesaid hot rolling method in which the preceding material to be rolled and the following material to be rolled are connected in the inlet side of the finishing mill, it is made possible to perform a thin material rolling by applying a stable tension over a whole length by means of continuously rolling one in which several tens of rolling raw materials are connected.
However, in case where a thin metal strip is coiled at high speed by using the aforesaid conventional apparatus for coiling a metal strip as shown in Fig. 7, the outer coiling face of the coil 5 is pushed by the wrapper roll 6 and, if the wrapper roll 6 impinge against a portion located in a step between an inner coiling most tip portion (metal strip tip) 5a of the coil 5 in an outer coiling face of the coil 5 and a surface of the mandrel 2 (hereafter, referred to as step portion 16), the step portion 16 is then rolled by a high pressure because the coil 5 is rotating at high speed. As a result, there is a drawback that a portion of the metal strip being coiled, located at the step portion 16 generates a shape defect, so that the process yield ratio decreases. And, it has been confirmed that this shaped defect becomes remarkable in case that a thickness is 2.3 mm or less and a coiling speed is 700 mpm or higher. Incidentally, it is frequent that the wrapper roll 6 is provided with a convex crown so that the aforesaid shape defect is mainly a center buckle.
Furthermore, there is described in Japanese Patent Laid-Open No. 126021/1981 Gazette and Japanese Patent Laid Open No. 92118/1984 Gazette, a method of buffering an impact force generated in the step portion by, in a machine for coiling a metal strip, performing an operation for raising at a coil step portion generated in a metal strip tip portion before an upper roll passes in the initial stage of coiling the metal strip on a mandrel to thereby avoid an impigement and lower the upper roll after it has passed. However, as mentioned before where the weight of one material to be rolled is large and the fact that one in which several tens of rolling raw materials are connected is continuously rolled and coiled at high speed are not assumed, there is not disclosed the fact that, when finishing the coiling, it is stopped rapidly by means of braking the coil rotation means of wrapper rolls.
Accordingly, in case that a continuous finish-rolling is performed or in a case where a large unit weight coil is rolled, since a high speed winding is performed, there is a drawback in that, in a case where there is a step portion in a coil outer coiling portion, the step portion is rolled by a high pressure and consequently this portion generates a shape defect.
The invention has been made in order to solve such a drawback, and its object is to provide a method of and an apparatus for coiling a metal strip, each of which is for improving the coiling of a metal strip such that no shape defect is generated when coiling a thin metal strip at high speed.
Disclosure of the Invention According to the present invention, there is provided a method of coiling a metal strip after a hot finish rolling adapted before the metal strip is coiled on a mandrel, plural wrapper rolls are pushed against an outer coiling face of a coil to brake a rotation of the coil, thereby stopping the rotation of the coil, characterized in that a position of a step portion appearing in an outer coiling face of the coil owing to a step between a leading end of the coil and a surface of the mandrel is detected, and a pushing force of each of the wrapper rolls is made 20 kN/m or lower only during a predetermined time before or after the step portion passes a position of each of the wrapper rolls.
Preferably, the method of coiling a metal strip is characterized in that the pushing force applied per 1 m coil width the wrapper roll on the step portion and on a portion other than the step portion is made 10 - 20 kN/m.
Preferably, the method of coiling a metal strip is characterized in that before the metal strip is finished to be coiled on the mandrel, the wrapper roll is approached from a waiting position nearer to the mandrel than an open limit toward the outer coiling face of the coil, thereby starting a pushing of the outer coiling face.
According to the present invention, there is also provided an apparatus for coiling a metal strip, having a mandrel for coiling the metal strip in a coil-like form, plural wrapper rolls for pushing an outer coiling face of a coil coiled on the mandrel, a support frame which supports each of the wrapper rolls and which is provided so as to be able to approach or separate from the outer coiling face of the coil, and drive means for causing the support frame to approach or separate from the outer coiling face of the coil, characterized by having strip shear controlling means for transmitting a coiling finish signal to a strip shear for cutting the metal strip after a hot finish rolling and to drive means for pushing each of the wrapper rolls against the outer coiling face of the coil, step portion position detecting means for detecting a position of a step portion appearing in the outer coiling face of the coil owing to a step between a leading end of the coil and a surface of the mandrel, and wrapper roll controlling means for controlling, on the basis of a detection position by the step portion position detecting means, the drive means such that a gap between the wrapper roll and the outer coiling face or a pushing force of the outer coiling face by each of the wrapper rolls is changed.
Preferably, the apparatus is characterized in that the step portion position detecting means has means for detecting, when starting to coil the metal strip, a position of a tip of the metal strip coiled on the mandrel, means for operating the tip position as a rotation angle 8 with respect to a predetermined position of the mandrel, means for storing the rotation angle 8, and means for operating, before the metal strip is finished to be coiled, the rotation angle 8 position of the step portion appearing in the outer coiling face of the coil.
Preferably, the apparatus for coiling a metal strip is characterized in that the rotation angle 8 is found by a sensor for detecting the fact that the metal strip tip has passed, a tachometer for detecting a rotating speed of the coil, and a sheet speed detecting sensor.
Preferably, the method of coiling a metal strip is characterized in that in case that a rotating speed of the coil is reduced to lower than a predetermined rotating speed, the pushing force of the wrapper roll is set so as to exceed 20 kN/m.
Brief Description of the Drawings Fig. 1 is a schematic view of an apparatus for coiling a metal strip, which is one example of 1st embodiment of the invention.
Fig. 2 is an explanatory view of the 1st embodiment of the invention which explains a relative operation of a wrapper roll with respect to a coil outer winding face in a coiling finish stage.
Fig. 3 is an explanatory view of the 1st embodiment of the invention, for explaining the relative operation of the wrapper roll with respect to the coil outer winding face in a pushing start time.
Fig. 4 is an explanatory view of 2nd embodiment of the invention, which explains the relative operation of the wrapper roll with respect to the coil outer winding face in the coiling finish stage.
Fig. 5 is an explanatory view of a 3rd embodiment of the invention, which explains the relative operation of the wrapper roll with respect to the oil outer winding face in the coiling finish stage.
Fig. 6 is a schematic view for explaining a conventional apparatus for coiling a metal strip.
Fig. 7 is an explanatory view for explaining a step portion appearing in an outer coiling face of a coil owing to a step between a leading end of the coil and a mandrel surface.
Hereunder, embodiments of the invention are explained by referring Fig. 1 - Fig. 5.
First, in explaining a 1st embodiment of the invention by referring to Fig. 1 - Fig. 3, in Fig. 1, the reference numeral 2 denotes a mandrel for coiling, through a pinch roll 4 , a metal strip 3 cut in a predetermined length by a strip shear (reference numeral 22 in Fig. &) after passing through a hot finishing mill (reference numeral 21 in Fig. 6) in a coil-like form, and plural wrapper rolls (four places in Fig. 1) 6 are arranged in a peripheral direction with a predetermined ' spacing in an outer coiling face side of a coil 5 coiled on the mandrel 2.
Each wrapper roll 6 is respectively supported by a support frame (only one place is shown in Fig. 1) 7 provided so as to be rotatable through a rotation supporting point Ta in a direction approaching or separating from an outer coiling face of the coil 5, and a piston rod 8a of a hydraulic cylinder (drive means) 8 is connected to the support frame 7. It is adapted such that, by extending the piston rod 8a, the support frame 7 is rotated in the direction approaching the outer coiling face of the coil 5 and thus the wrapper roll 6 contacts with the outer coiling face and, by retracting it, the support frame 7 is rotated in the direction separating from the outer coiling face of the coil 5 and thus the wrapper roll 6 separates from the outer coiling face.
Further, between the coil 5 and the pinch roll 4, there is arranged a laser sensor 9 for detecting the fact that a tip of the metal strip 3 has passed, a detection sensor 10 for detecting a rotating speed and a rotation angle of the coil is attached to the mandrel 2 , a sheet speed detecting sensor 11 for detecting a carrying speed (sheet speed) of the metal strip 3 is attached to the pinch roll 4, a rotation angle detecting sensor 12 for detecting a rotation angle is attached to the support frame 7, and pressure detecting sensors 13a, 13b for detecting a working pressure are attached to the hydraulic cylinder 8. And, it is adapted such that, on the basis o~f a signal from each sensor, a controller 14 controls the hydraulic cylinder 8 through a drive circuit 15.
The controller 14 has an operation section 17 for operating, on the basis of the signals from the laser sensor 9 , the rotating speed sensor 10 and the sheet speed detecting sensor 11, an inner coiling most tip portion 5a of the coil as a rotation angle 8 from a predetermined position of the mandrel, a tip step portion storing section 19 for storing the A, the operation section 17 for operating,' on the basis of a signal from a strip shear controlling section 20 before finishing the coiling of the metal strip, the 8 as a position of a step portion 16 appearing in the outer coiling face of the coil 5 owing to a step between the coil and a surface of the mandrel 2, and a control section (control means)18 for performing a position control and a pushing force control of the wrapper roll 6 with respect to the outer coiling face of the coil 5 by controlling the hydraulic cylinder 8 through the drive circuit 15. Here, in this embodiment, step portion position detecting means of the invention is constituted by the laser sensor 9, the rotating speed detecting sensor 10, the sheet speed detecting sensor 11, the operation section 17 , the tip step portion storing section 19 and the strip shear controlling section 20, but it may be adapted such that the position of the step portion 16 is detected by another publicly known detecting means or tracking means and the like.
The control section 18 is adapted so as to control the hydraulic cylinder 8 in a coiling start stage and a coiling finish stage. In the coiling start stage, in order to surely perform a coiling start operation, the piston rod 8a of the hydraulic cylinder 8 is extended synchronizing with a coiling start timing of a tip of the metal strip 3 , which is obtained on the basis of the signal from the laser sensor 9 and, by this , the support frame 7 is rotated by a predetermined angle in the direction approaching an outer face of the mandrel 2, thereby sandwiching the tip of the metal strip 3 between the wrapper roll 6 and the mandrel 2. Further, after a predetermined time has elapsed from the coiling start, the support frame 7 is rotated by a predetermined angle in the direction separating from the outer coiling face of the coil 5 by retracting the piston rod 8a and, by this, the wrapper roll 6 is caused to wait at a predetermined position by being shunted from the outer coiling face of the coil 5 until a predetermined time before the coiling is finished.
Incidentally, an extension/retraction amount of the piston rod 8a of the hydraulic cylinder 8 in this case is controlled such that a detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle (this is stored in a storage area of the control section 18) of the support frame 7, which is previously set in compliance with a sandwiching position of the metal strip 3 tip and a shunting position at the wrapper roll 6. Further, at the coiling start time, the aforesaid step portion 16 appears in the coil 5 outer coiling face between the wrapper roll 6 and the mandrel 2 correspondingly to the step between the most tip portion (metal strip tip) 5a of the metal strip 3 and the surface of the mandrel 2.
On the other hand, in the coiling finish stage, on the basis of a tail end wrapper roll pushing start signal from the strip shear controlling unit 20, first, when starting a pushing by the wrapper roll 6 against the coil 5 outer coiling face, it is judged whether or not the position 8, of the metal strip tip portion, operated by the operation section 17 on the basis of the signals from the laser sensor 9, the rotating speed detecting sensor 10 and the sheet speed detecting sensor 11 agrees with a contact position, stored in the storing section 19, of the wrapper roll 6 with respect to the coil 5 outer coiling face. In case that it does not agree with, the piston rod 8a of the hydraulic cylinder 8 is extended synchronizing with a previously set pushing start timing in order to~brake the rotation of the coil 5 to stop it in a short time and, by this , the support frame 7 is rotated by a predetermined angle in the direction approaching the outer coiling face of the coil , thereby bringing the wrapper roll 6 into contact with the coil 5 outer coiling face.
In case that a position of the step portion 16 agrees with a contact start position of the wrapper roll 6 , as shown in Fig. 3, the piston rod 8a of the hydraulic cylinder 8 is retracted before a predetermined time at which the step portion 16 reaches the contact start position of the wrapper roll 6 in order to avoid the contact and, by this, the support frame 7 is rotated by a predetermined angle in the direction separating from the outer coiling face of the coil 5 to thereby shunt the wrapper roll 6 from the coil 5 outer coiling and, after a predetermined time has elapsed from when the position of the step portion 16 has passed a contact position of the wrapper roll 6, the piston rod 8a of the hydraulic cylinder 8 is extended and, by this, the support frame 7 is rotated by a predetermined angle in the direction approaching the outer coiling face of the coil 5, thereby bringing the wrapper roll 6 into contact with the coil 5 outer coiling face.
Incidentally, an extension/retraction amount of the piston rod 8a of the hydraulic cylinder 8 in this case is controlled such that a detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle (this is stored in a storage area of the control section 18 ) of the support frame 7, which is previously set in compliance with a contact position and a shunting position with respect to the outer coiling face of the coil 5 at the wrapper roll 6.
After the wrapper roll 6 has contacted with the outer coiling face of the coil 5, the hydraulic cylinder 8 is controlled such that a detection pressure obtained from the pressure detecting sensors 13a, 13b agrees with a previously set working pressure for applying a predetermined pushing force to the outer coiling face of the coil 5. Here, a pushing force per a lm coil width of the wrapper roll 6 with respect to the outer coiling face of the coil 5 is made a range of 10 - 20 kN/m. If the pushing force is lower than 20 kN/m, a braking force necessary for a rotation of the coil is not obtained and, further, it is impossible to suppress a bulge of coil outer periphery portion owing to a centrifugal force at high speed rotation time. On the other hand, if it exceeds 20 kN/m, a high pressure is generated when the wrapper roll 6 impinges against the step portion 16 of the coil 5 rotating at high speed, so that a center buckle occurs in the coil 5.
Next, it is explained about an actuation of the control section 18.
First, in the coiling start stage, the piston rod 8a of the hydraulic cylinder 8 is extended synchronizing with the coiling start timing of the tip of the metal strip 3, which is obtained on the basis of the signal from the laser sensor 9 , such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7, previously set in compliance with a sandwiching position of the metal strip 3 tip at the wrapper roll 6 , thereby rotating the support frame 7 in the direction approaching the outer face of the mandrel 2 and, by this, the tip of the metal strip 3 is sandwiched between the wrapper roll 6 and the mandrel 2, thereby surely performing a coiling start operation.
Further, after a predetermined time has elapsed from the coiling start, the piston rod 8a is retracted such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7, previously set in compliance with a shunting position of the wrapper roll 6, thereby rotating the support frame 7 in the direction separating from the outer coiling face of the coil and, by this, the wrapper roll 6 is shunted from the outer coiling face of the coil 5 until a predetermined time before the coiling is finished, thereby causing it to wait in a predetermined position. Incidentally, as to this waiting position, it is advantageous to locate it as nearly to the mandrel as possible than a open limit of the wrapper roll, because an operation for pushing the wrapper roll at a coiling finish time can be rapidly performed.
In the coiling finish stage, first, when starting the pushing by the wrapper roll 6 against the coil 5 outer coiling face, it is judged whether or not the position of the step portion 16 agrees with the contact position of the wrapper roll 6. In case that it does not agree with, the piston rod 8a of the hydraulic cylinder 8 is extended synchronizing with the previously set pushing start timing such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7 , previously set in compliance with the contact position with respect to the outer coiling face of the coil 5 at the wrapper roll 6 in order to brake the rotation of the coil 5 to stop it in a short time and, by this , the support frame 7 is rotated in the direction approaching the outer coiling face of the coil 5, thereby bringing the wrapper roll 6 into contact with the coil 5 outer coiling face.
In case that the position of the step portion 16 agrees with the contact position of the wrapper roll 6, as shown in Fig. 3, the piston rod 8a of the hydraulic cylinder 8 is retracted before the predetermined time at which the position of the step portion 16 reaches the contact position of the wrapper roll 6 such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7 , previously set in compliance with the shunting position with respect to the coil 5 outer coiling face of the wrapper roll 6 in order to avoid the contact and, by this, the support frame 7 is rotated in the direction separating from the outer coiling face of the coil 5 to thereby shunt the wrapper roll 6 from the coil 5 outer coiling and, after the predetermined time has elapsed from when the position of the step portion 16 has passed the contact position of the wrapper roll 6 , the piston rod 8a of the hydraulic cylinder 8 is extended such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with a rotation angle, of the support frame 7, previously set in compliance with the contact position with respect to the coil 5 outer coiling face of the wrapper roll 6 and, by this, the support frame 7 is rotated by in the direction approaching the outer coiling face of the coil 5, thereby bringing the wrapper roll 6 into contact with the coil outer coiling face.
After the wrapper roll 6 has contacted with the outer coiling face of the coil 5, the hydraulic cylinder 8 is controlled such that the detection pressure obtained from the pressure detecting sensors 13a, 13b can obtain a previously set braking force necessary for the rotation of the coil 5 and agrees with a working pressure for giving a pushing pressure - 20 kN/ m per a coil width 1 m, under which no shape defect occurs even if the wrapper coil 6 impinges against the step portion 16 of the coil 5 rotating at high speed, to the outer coiling face of the coil 5, the outer coiling face of the coil 5 is continued to be pushed by this pushing force until the coil 5 is speed-reduced to a predetermined rotating speed (speed at which no shape defect occurs in the step portion 16 even if the wrapper roll 6 pushed by the pushing force exceeding 20 kN/m impinges against the step portion 16 of the rotating coil 5: lower than 700 mpm), and, after it has been speed-reduced to the predetermined rotating speed, the pushing force is increased to exceed 20 kN/rn, thereby increasing a rotation braking force of the coil 5.
As apparent from the above explanations, according to this embodiment, in the coiling finish stage, since it is adapted such that the braking force necessary for the rotation of the coil 5 is obtained and the outer coiling face of the coil 5 is pushed by the pushing force under which no shape defect occurs even if the wrapper coil 6 impinges against the step portion 16 of the coil 5 rotating at high speed, it is possible to adapt such that no shape defect occurs in the metal strip existing in a step portion 16 position after a thin (2.3 mm or less) metal strip is coiled at high speed (700 mpm or higher) as the coil and, as a result, it is possible to increase a process yield ratio.
Further, at a pushing start time of the coil 5 outer face by the wrapper roll 6, since it is adapted such that the wrapper roll 6 does not contact with the step portion 16, the impingement between the wrapper roll 6 and the step portion 16 of the coil 5 rotating at high speed is avoided at the pushing start time, so that an occurrence of the shape defect can be surely prevented.
Incidentally, in the aforesaid embodiment, as an example there is adopted a case in which the invention is applied when coiling the metal strip 3 cut in a predetermined length by the strip shear into a coil-like form, but it is needless to say that the invention may be applied to an ordinary batch rolling.
Further, as shown in Fig. 2, the wrapper roll may be always pushed by a constant pressure irrespective of whether or not the step portion 16 exists by means of controlling the hydraulic cylinder 8 so as to agree with a working pressure for giving the pushing force 10 - 20 kN/m to the outer coiling face of the coil 5. It is also possible that the outer coiling face of the coil 5 is continued to be pushed by this pushing force until the coil 5 is speed-reduced to the predetermined rotating speed as mentioned before and, after it is speed-reduced to the predetermined rotating speed (lower than 700 mpm), the pushing force is increased to enhance a rotation braking force of the coil 5.
Next, it is explained about a method of coiling a metal strip, which is an embodiment of a 2nd mode of the invention, by referring to Fig. 1 and Fig. 4. Incidentally, this coiling method differs with respect to the aforesaid coiling device 1 only in a controlling method of the hydraulic cylinder 8 by the control section 18 of the controller 14 after the wrapper roll 6 has contacted with the outer coiling face of the coil in the coiling finish stage.
After the wrapper roll 6 has contacted with the outer coiling face of the coil 5 in the coiling finish stage, the control section 18 controls the hydraulic cylinder 8 such that the detection pressure obtained from the pressure detecting sensors 13a, 13b agrees with a previously set working pressure for giving a pushing force forcedly braking the rotation of the coil 5 to the outer coiling face of the coil 5 until a predetermined time before the position, of the step portion 16, operated by the operation section 17 on the basis of the signals from the laser sensor 9 , the rotating speed detecting sensor 10 and the sheet speed detecting sensor 11 reaches a contact position, of the wrapper roll 6 with respect to the coil 5 outer coiling face, previously stored in the storage area (not shown) . It is preferable that the pushing force on this occasion is a large value (exceeding 20 kN/m) in order that a braking force for the rotation of the coil 5 by the wrapper roll 6 is obtained.
Further, during a time from a predetermined time at which the step portion 16 reaches the contact position of the wrapper roll 6 to a time point at which a predetermined time has elapsed after the step portion 16 has passed the contact position of the wrapper roll 6 , the hydraulic cylinder 8 is controlled such that the detection pressure obtained from the pressure detecting sensors 13a, 13b gives a weak pushing force (20 kN/m or lower) previously set such that no shape defect occurs in the step portion 16 even if the wrapper roll 6 impinges against the step portion 16 of the coil 5 rotating at high speed.
Incidentally, the control for weakening the pushing force by the wrapper roll 6 is performed until the coil 5 is speed-reduced to a predetermined rotating speed (speed at which no shape defect occurs in the step portion 16 even if the wrapper roll 6 pushing by a strong pushing force (exceeding 20 kN/m) impinges against the step portion 16 of the rotating coil 5:
lower than 700 mpm) and, after being speed-reduced to the predetermined rotating speed, the pushing force is increased to enhance the rotation braking force of the coil 5.
As apparent from the above explanations, in this embodiment since it is adapted such that, in the coiling finish stage, a sufficient braking force is obtained for the rotation of the coil 5 and, before and after the step portion 16 passes the contact position of the wrapper roll 6, the outer face of the coil 5 is pushed by such a weak pushing force that no shape defect occurs in the step portion 16 even if the wrapper roll 6 impinges against the step portion 16 of the coil 5 rotating at high speed, it is possible, after coiling the coil 5 of the thin (2.3 mm or less) metal strip at high speed (700 mpm or higher) , to prevent the shape defect from occurring in the metal strip and, as a result, the improvement in yield can be intended.
Incidentally, since another action/effect is the same as the embodiment of the 1st mode mentioned above, its explanation is omitted.
Next, it is explained about a method of coiling a metal strip, which is an embodiment of a 3rd mode of the invention, by referring to Fig. 1 and Fig. 5. Incidentally, also this coiling method differs with respect to the aforesaid coiling device 1 only in a controlling method of the hydraulic cylinder 8 by the control section of the controller 14 after the wrapper roll 6 has contacted with the outer coiling face of the coil in the coiling finish stage.
After the wrapper roll 6 has contacted with the outer coiling face of the coil 5 in the coiling finish stage, the control section 18 controls the hydraulic cylinder 8 such that the detection pressure obtained from the pressure detecting sensors 13a, 13b agrees with the previously set working pressure for giving the pushing force forcedly braking the rotation of the coil 5 to the outer coiling face of the coil 5 until the predetermined time before the position, of the step portion 16, operated by the operation section 17 on the basis of the signals from the laser sensor 9, the rotating speed detecting sensor 10 and the sheet speed detecting sensor 11 reaches the contact position, of the wrapper roll 6 with respect to the coil 5 outer coiling face, previously stored in the storage area (not shown).
Further, during the time from the predetermined time at which the step portion 16 reaches the contact position of the wrapper roll 6 to the time point at which the predetermined time has elapsed after the step portion 16 has passed the contact position of the wrapper roll 6, the piston rod 8a of the hydraulic cylinder 8 is retracted such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with the rotation angle, of the support frame 7, previously set in compliance with the shunting position of the wrapper roll 6 with respect to the coil 5 outer coiling face and, by this, the support frame 7 is rotated in the direction separating from the outer coiling face of the coil 5, thereby controlling the wrapper coil 6 so as to be shunted from the coil 5 outer coiling face.
Further, after a predetermined time has elapsed from a time point at which the position of the step portion 16 has passed the aforesaid contact position, the piston rod 8a of the hydraulic cylinder 8 is extended such that the detection angle obtained by the rotation angle detecting sensor 12 agrees with the rotation angle, of the support frame 7, previously set in compliance with the contact position of the wrapper roll 6 with respect to the coil 5 outer coiling face and, by this , the support frame 7 is rotated in the direction approaching the outer coiling face of the coil 5, thereby bringing the wrapper roll 6 into contact with the coil 5 outer coiling face and, thereafter, the hydraulic cylinder 8 is rapidly controlled such that the detection pressure obtained from the pressure detecting sensors 13a, 13b agrees with a previously set working pressure for giving a pushing force forcedly braking the rotation of the coil 5 to the outer coiling face of the coil 5.
Incidentally, the control for shunting the wrapper roll 6 from the step portion 16 is performed until the coil 5 is speed-reduced to a predetermined rotating speed (speed at which no center buckle occurs in the coil 5 even if the wrapper roll 6 impinges against the step portion 16 of the rotating coil 5) and, after it has been speed-reduced to the predetermined rotating speed (lower than 700 mpm), the pushing force is increased to enhance the rotation braking force of the coil 5.
As apparent from the above explanations, in this embodiment since it is adapted such that, in the coiling finish stage, a sufficient braking force is obtained for the rotation of the coil 5 and, before and after the step portion 16 passes the contact position of the wrapper roll 6, the wrapper roll 6 does not impinge against the step portion 16 of the coil 5 rotating at high speed, it is possible, after coiling the thin (2.3 mm or less) metal strip into the coil 5 at high speed (700 mpm or higher) , to prevent the shape defect from occurring in the metal strip and, as a result, the improvement in yield can be intended. Incidentally,since another action/effect is the same as the embodiment of the 1st mode mentioned above, its explanation is omitted.
Industrial A~~licabilitv As apparent from the above explanations, according to the invention, since it is possible to adapt such that, after coiling the thin metal strip into the coil at high speed, no shape defect occurs in the coiled metal strip, there is obtained an effect that the improvement in yield can be intended.
Further, when starting to push the coil outer coiling face by the wrapper roll, since the impingement between the wrapper roll and the step portion of the coil rotating at high speed can be avoided at the pushing start time by controlling the wrapper roll so as not to contact with the step portion, there is obtained an effect that an occurrence of the shape defect can be surely prevented.
Claims (7)
1. A method of coiling a metal strip after a hot finish rolling adapted before the metal strip is coiled on a mandrel, plural wrapper rolls are pushed against an outer coiling face of a coil to brake a rotation of the coil, thereby stopping the rotation of the coil, characterized in that a position of a step portion appearing in an outer coiling face of the coil owing to a step between a leading end of the coil and a surface of the mandrel is detected, and a pushing force of each of the wrapper rolls is made 20 kN/m or lower only during a predetermined time before and after the step portion passes a position of each of the wrapper rolls.
2. A method of coiling a metal strip of claim 1, characterized in that each of the wrapper rolls is separated from the outer coiling face of the coil only when the step portion passes the position of each of the wrapper rolls.
3. A method of coiling a metal strip of claim 1 or 2, characterized in that, before the metal strip is finished to be coiled on the mandrel, each of the wrapper rolls is pushed against an outer coiling face from a waiting position nearer to the mandrel than the open limit toward the outer coiling face of the coil, thereby starting a breaking of the outer coiling face.
4. A method of coiling metal strip of claim 1, characterized in that, in case that a rotating speed of the coil is reduced to lower than a predetermined rotating speed, the pushing force of the wrapper roll is set so as to exceed 20 kN/m.
5. An apparatus for coiling a metal strip, having a mandrel for coiling the metal strip in a coil-like form, plural wrapper rolls for pushing an outer coiling face of a coil coiled on the mandrel, a support frame which supports each of the wrapper rolls and which is provided so as to be able to approach or separate from the outer coiling face of the coil, and drive means for causing the support frame to approach or separate from the outer coiling face of the coil, characterized by having strip shear controlling means for transmitting a coiling finish signal to a strip shear for cutting the metal strip after a hot finish rolling and to drive means for pushing each of the wrapper rolls against the outer coiling face of the coil, step portion position detecting means for detecting a position of a step portion appearing in the outer coiling face of the coil owing to a step between a leading end of the coil and a surface of the mandrel, and wrapper roll controlling means for controlling, on the basis of a detection position by the step portion position detecting means, the drive means such that a gap between the wrapper roll and the outer coiling face or a pushing force of the outer coiling face by each of the wrapper rolls is changed.
6. An apparatus for coiling a metal strip of claim 5, characterized in that the step portion position detecting means has:
means for detecting, when starting to wind the metal strip, a position of a leading end of the coil on the mandrel, means for operating the tip position as a rotation angle .theta. with respect to a predetermined position of the mandrel, means for storing the rotating angle .theta., and means for operating, before the metal strip is finished to be coiled, the rotation angle .theta. as the position of the step portion appearing in the outer coiling face of the coil.
means for detecting, when starting to wind the metal strip, a position of a leading end of the coil on the mandrel, means for operating the tip position as a rotation angle .theta. with respect to a predetermined position of the mandrel, means for storing the rotating angle .theta., and means for operating, before the metal strip is finished to be coiled, the rotation angle .theta. as the position of the step portion appearing in the outer coiling face of the coil.
7. An apparatus for coiling a metal strip of claim 6, characterized in that the rotation angle .theta. is determined by:
a sensor for detecting the fact that the metal strip tip has passed, a rotation speedometer for detecting a rotating speed of the coil, and a sheet speed detecting sensor.
a sensor for detecting the fact that the metal strip tip has passed, a rotation speedometer for detecting a rotating speed of the coil, and a sheet speed detecting sensor.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/JP1999/005192 WO2001021335A1 (en) | 1999-09-22 | 1999-09-22 | Method device for winding metal strips |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2351757A1 CA2351757A1 (en) | 2001-03-29 |
| CA2351757C true CA2351757C (en) | 2005-12-06 |
Family
ID=14236785
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002351757A Expired - Fee Related CA2351757C (en) | 1999-09-22 | 1999-09-22 | Method device for winding metal strips |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP1132155B1 (en) |
| KR (1) | KR100604504B1 (en) |
| CN (1) | CN1203936C (en) |
| CA (1) | CA2351757C (en) |
| DE (1) | DE69922242T2 (en) |
| ES (1) | ES2234292T3 (en) |
| WO (1) | WO2001021335A1 (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10142179A1 (en) | 2001-08-29 | 2003-03-20 | Sms Demag Ag | Method and device for reeling thin metal strip, in particular hot or cold rolled thin steel strip |
| KR100860317B1 (en) * | 2002-07-24 | 2008-09-26 | 주식회사 포스코 | Holding apparatus with means for preventing upset and correcting telescope of the coil |
| KR100883822B1 (en) * | 2002-11-30 | 2009-02-16 | 주식회사 포스코 | Method for controlling strip head end positioning On Free Tension Reel |
| AT503109B1 (en) * | 2005-10-18 | 2007-08-15 | Voest Alpine Ind Anlagen | HOSE PAN WITH A BELT HASPING DEVICE |
| AT504219B1 (en) * | 2006-10-02 | 2008-06-15 | Siemens Vai Metals Tech Gmbh | REEL OVEN |
| EP1977839A1 (en) * | 2007-04-05 | 2008-10-08 | Siemens VAI Metals Technologies Ltd. | Dual pivot ironing roll |
| CN102476756B (en) * | 2010-11-25 | 2014-07-30 | 软控股份有限公司 | Method for controlling material winding speed |
| JP5807835B2 (en) * | 2011-01-13 | 2015-11-10 | 株式会社Ihi | Ironing equipment |
| CN103341524A (en) * | 2013-04-18 | 2013-10-09 | 首钢京唐钢铁联合有限责任公司 | Calibration method for wrapper roll gaps of coiler |
| CN104512748B (en) * | 2013-09-30 | 2017-01-18 | 宝山钢铁股份有限公司 | Control method of coiling apparatus |
| CN104438438B (en) * | 2014-11-08 | 2016-09-14 | 马钢(集团)控股有限公司 | A kind of CSP of correction batches the method for Wrapping Roll roll gap precision |
| KR102653434B1 (en) * | 2016-12-06 | 2024-04-02 | 가부시키가이샤 에프에이덴코 | Drawing machine and drawing method |
| TWI657872B (en) * | 2018-09-06 | 2019-05-01 | 中國鋼鐵股份有限公司 | Method and computer program product for regulating pressure from wrap rolls to steel belt |
| JP7413547B2 (en) * | 2020-01-22 | 2024-01-15 | ノベリス・インコーポレイテッド | Detecting and canceling force of events during coil-forming operations |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05154550A (en) * | 1991-12-09 | 1993-06-22 | Kawasaki Steel Corp | Method for stopping of coil |
| JPH08141638A (en) * | 1994-09-22 | 1996-06-04 | Sumitomo Metal Ind Ltd | Control method of wrapper roll and its device |
| JP3193338B2 (en) * | 1998-03-26 | 2001-07-30 | 川崎製鉄株式会社 | Coil winding method and apparatus |
-
1999
- 1999-09-22 EP EP99944786A patent/EP1132155B1/en not_active Expired - Lifetime
- 1999-09-22 CA CA002351757A patent/CA2351757C/en not_active Expired - Fee Related
- 1999-09-22 DE DE69922242T patent/DE69922242T2/en not_active Expired - Lifetime
- 1999-09-22 WO PCT/JP1999/005192 patent/WO2001021335A1/en active IP Right Grant
- 1999-09-22 KR KR1020017006314A patent/KR100604504B1/en not_active IP Right Cessation
- 1999-09-22 ES ES99944786T patent/ES2234292T3/en not_active Expired - Lifetime
- 1999-09-22 CN CNB998155527A patent/CN1203936C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| DE69922242D1 (en) | 2004-12-30 |
| KR20010107974A (en) | 2001-12-07 |
| KR100604504B1 (en) | 2006-07-25 |
| CN1203936C (en) | 2005-06-01 |
| CA2351757A1 (en) | 2001-03-29 |
| CN1333710A (en) | 2002-01-30 |
| EP1132155A4 (en) | 2003-01-08 |
| ES2234292T3 (en) | 2005-06-16 |
| WO2001021335A1 (en) | 2001-03-29 |
| DE69922242T2 (en) | 2005-12-22 |
| EP1132155A1 (en) | 2001-09-12 |
| EP1132155B1 (en) | 2004-11-24 |
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