Steel coil uncoiling control method for hot coil box

Abstract

The present invention relates to a method for controlling the uncoiling of a steel coil in a hot coil box, belonging to the technical field of uncoiling for producing metal strips by non-rolling methods. This method reduces the weight of the blade holder on one side and increases the weight of the blade holder on the other side, so that the blade assembly forms a first included angle with the horizontal plane by the connecting line between the outer circle of the small idler and the vertex of the blade under its own weight; for large steel coils, a first height difference is formed between the first roller and the second roller, and for small steel coils, a second height difference is formed between the first roller and the second roller; when using a conventional oil cylinder for uncoiling, first control the piston rod of the oil cylinder to fully extend, so that the large swing arm and the insertion arm do not rotate relative to each other and form a second included angle; control the large swing arm to rotate downward with the first hinge point as the center and keep the second included angle unchanged. When the large swing arm approaches the outer surface of the steel coil, the mechanical stop blocks against the boss to make the blade head assembly fixed and keep the first included angle unchanged; control the large swing arm to continue to rotate downward, the small idler first contacts the outer surface of the steel coil, and then the small guide wheel contacts the outer surface of the steel coil and makes the piston rod of the oil cylinder retract, and the insertion arm rotates relative to the large swing arm to make the second included angle and the first included angle gradually increase, completing the uncoiling of the steel coil. This method can maintain the effectiveness of mechanical limit and avoid the easy occurrence of coil flipping when uncoiling small steel coils.

Description

Technical Field

[0001] The present invention relates to a method for controlling the uncoiling of a steel coil in a hot coil box, and belongs to the technical field of uncoiling for producing metal strips by a non-rolling method. Background Art

[0002] The main function of the hot coil box is to wind the intermediate billet of rough rolling without a mandrel, and then through uncoiling, turn the tail of the intermediate billet into the head, the lower surface into the upper surface, and send it into the finishing mill for rolling. Its greatest feature is that it can eliminate the temperature difference between the head and the tail, ensure the product quality, improve the stability of thin gauge and varieties with large deformation resistance, improve the influence of secondary scale on the surface quality, and improve the descaling effect. The uncoiling device of the hot coil box mainly includes a rack cylinder, a servo hydraulic mechanism, an uncoiling large swing arm, an insertion arm, a shovel head assembly, etc. Among them, the large swing arm and the insertion arm form a hinge joint. The rack cylinder is connected and drives the large swing arm to rotate up and down. The servo hydraulic mechanism is connected to the insertion arm and expands and contracts as the insertion arm rotates. A limit mechanical stop is provided on the insertion arm. When the mechanical stop abuts against the convex block on the shovel head assembly, the swing of the shovel head assembly during the rotation and lowering of the large swing arm can be restricted.

[0003] The currently used uncoiling device of the hot coil box has the following disadvantages: 1. During the rotation and lowering of the large swing arm, the insertion arm rotates relative to the large swing arm, so that the swing angle of the shovel head assembly is too large, which will damage the limit mechanical stop and cause the shovel head to tip over, making uncoiling impossible. 2. When uncoiling a steel coil with a small weight, the phenomenon of coil flipping is likely to occur.

[0004] Chinese Patent No. CN103521553 discloses a control method for an uncoiler of a hot coil box. This method controls the angle of the shovel and the angle value of the entire shovel head assembly by adjusting the rotation of the insertion arm through the cylinder pressure of the servo hydraulic mechanism. The entire control process of this method is relatively complex and must be controlled by servo ratios and key sensors such as position, angle, and pressure; moreover, it still cannot avoid the coil flipping that is likely to occur when uncoiling a small steel coil. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: by adjusting the specific control of the uncoiling device during uncoiling of the hot coil box, so that the swing angle of the shovel head assembly is reduced and it is in a suitable angle after mechanical limit and the effectiveness of the mechanical limit is maintained, and at the same time, the coil flipping that is likely to occur when uncoiling a small steel coil is avoided.

[0006] The technical solution proposed by the present invention to solve the above technical problems is: a method for controlling the uncoiling of steel coils of a hot coil box, the uncoiling device of the hot coil box comprising a large swing arm, an insertion arm, a rack cylinder, an oil cylinder, a scraper assembly, a first roller and a second roller supporting the steel coil, the large swing arm having a first hinge point driven by the rack cylinder to rotate, the large swing arm and one end of the insertion arm forming a second hinge point, the insertion arm can be driven by the oil cylinder to rotate at the second hinge point, the scraper assembly is arranged at the other end of the insertion arm, the other end of the insertion arm is also provided with a mechanical stopper, the scraper assembly comprises a scraper frame, a rotating shaft located in the middle of the scraper frame, a small pressure wheel located on one side of the center of the rotating shaft, a small guide wheel and a scraper located on the other side of the center of the rotating shaft, and a boss is provided on the top of the scraper frame; it is characterized in that the following steps are performed:

[0007] 1) With the center of the shaft as the boundary, reduce the weight of the blade frame on one side of the shaft center and increase the weight of the blade frame on the other side of the shaft center by drilling or adding counterweights; make the first angle formed by the outer circle of the small pressure wheel and the line connecting the apex of the blade and the horizontal plane of the blade assembly under its own weight be 20-21 degrees;

[0008] 2) After the coiling is completed, if the outer diameter of the steel coil is greater than 1400mm, the first roller is dropped, and the position of the second roller remains unchanged, so that the first roller and the second roller form a first height difference; if the outer diameter of the steel coil is less than or equal to 1400mm, the first roller is lifted and the second roller is dropped, so that the first roller and the second roller form a second height difference;

[0009] 3) The oil cylinder is a cylinder without a servo mechanism. When unwinding, the piston rod of the oil cylinder is first controlled to be fully extended, so that the large swing arm and the insertion arm do not rotate relative to each other and form a second angle;

[0010] 4) Controlling the rack cylinder to drive the large swing arm to rotate downward with the first hinge point as the center, while keeping the second angle unchanged; when the large swing arm approaches the outer circular surface of the steel coil, the mechanical stopper abuts against the boss to fix the shovel head assembly, while keeping the first angle unchanged;

[0011] 5) Controlling the rack cylinder to drive the large swing arm to continue to rotate downward, the small pressure wheel first contacts the outer circumferential surface of the steel coil and moves downward along the outer circumferential surface of the steel coil, and the small guide wheel does not contact the surface of the steel coil;

[0012] 6) Control the rack cylinder to drive the large swing arm to continue to rotate downward, and the small guide wheel contacts the outer cylindrical surface of the steel coil and moves downward along the outer cylindrical surface of the steel coil. At this time, the piston rod of the oil cylinder retracts, and the insertion arm rotates relative to the large swing arm. The second angle and the first angle gradually increase, and the unwinding of the steel coil is completed.

[0013] Furthermore, the first height difference is 60 - 70 mm, and the second height difference is 110 - 120 mm.

[0014] The beneficial effects of the present invention are as follows:

[0015] 1) By adjusting the weight of the cutter blade holder on one side of the rotation axis center of the cutter blade assembly, the weight on one side of the rotation axis center (i.e., the side of the small pressure wheel) is reduced, while the weight on the other side of the rotation axis center (i.e., the side of the small guide wheel and the cutter blade) is increased. Therefore, under the action of its own weight, the cutter blade assembly is prone to form a clockwise rotation along its rotation axis center, so that the first included angle formed by the connection line between the outer circle of the small pressure wheel and the vertex of the cutter blade and the horizontal plane can reach 20 - 21 degrees, which can reduce the swing amplitude of the cutter blade assembly when the large swing arm rotates downward; and maintaining the first included angle can ensure that the small pressure wheel contacts the steel coil first, and then the small guide wheel and the cutter blade contact the steel coil. In this way, when the small pressure wheel contacts the steel coil first, it can cause the cutter blade assembly to rotate clockwise to offset the impact force of the steel coil on the cutter blade assembly and its convex block on the mechanical stop block, and can also reduce the amplitude of the counterclockwise rotation of the cutter blade assembly caused by the reaction force generated after the small guide wheel contacts the steel coil, thereby reducing the impact of the cutter blade assembly and its convex block on the mechanical stop block and ensuring the limit of the mechanical stop block on the cutter blade assembly.

[0016] 2) By using a conventional oil cylinder without a servo mechanism to replace the existing servo hydraulic mechanism and controlling the piston rod of the oil cylinder to fully extend first during uncoiling, the large swing arm and the insertion arm do not rotate relative to each other and form a fixed second included angle; therefore, not only the complex servo control and hydraulic control are reduced, but also when the large swing arm starts to rotate downward, it does not rotate relative to the insertion arm, so that the cutter blade assembly can be further ensured to maintain the first included angle.

[0017] 3) By reasonably adjusting the height difference (relative distance) between the first roller and the second roller for carrying large and small steel coils, especially when opening small steel coils, by increasing the height difference between the first roller and the second roller, a "nest" is formed between the first roller and the second roller, which can effectively prevent the small steel coil from forming a rolled-up coil during uncoiling. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The following further describes the steel coil uncoiling control method of the hot coil box of the present invention with reference to the drawings.

[0019] Figure 1 is a schematic structural diagram of the uncoiling device in the steel coil uncoiling control method of a hot coil box in an embodiment.

[0020] Figure 2 is Figure 1 a schematic structural diagram of the upper part rotating mechanism of the uncoiling device in

[0021] Figure 3 is Figure 2 an enlarged schematic structural diagram of the cutter blade assembly intercepted in

[0022] Figures 4-1 to 4-5 It is a diagram showing the uncoiling process of the steel coil uncoiling control method of a hot coil box in an embodiment. Detailed implementation manners Embodiment

[0023] A steel coil uncoiling control method for a hot coil box in this embodiment involves an uncoiling device of the hot coil box as shown in Figure 1 、 Figure 2 and Figure 3 , and includes a large swing arm 2, an insertion arm 3, a rack cylinder 9, an oil cylinder 1, a shovel blade assembly 4, a first roller 6 and a second roller 7 for supporting the steel coil 5. The large swing arm 2 has a first hinge point A driven to rotate by the rack cylinder. The rack cylinder 9 is sleeved on the spline shafts on both sides of the large swing arm 2 and fixedly installed on the coiling housing of the hot coil box (not shown in the figure). One end of the large swing arm 2 and the insertion arm 3 form a second hinge point B. The insertion arm 3 is driven by the oil cylinder 1 to rotate at the second hinge point B, and the shovel blade assembly 4 is arranged at the other end of the insertion arm 3.

[0024] As shown in Figure 3 , a mechanical stop 8 is provided at the other end of the insertion arm 3. The shovel blade assembly includes a shovel blade frame 401, a rotating shaft 402 located in the middle of the shovel blade frame 401, a small pressing wheel 403 located on one side of the center C of the rotating shaft 402, a small guide wheel 404 located on the other side of the center C of the rotating shaft 402, and a shovel blade 405. A boss 406 is provided at the top of the shovel blade frame 401. A steel coil uncoiling control method for a hot coil box in this embodiment specifically performs the following steps:

[0025] 1) Taking the center C of the rotating shaft 402 as the boundary, by drilling holes or adding weights, reduce the weight of the shovel blade frame 401 on one side of the center C of the rotating shaft 402 and increase the weight of the shovel blade frame 401 on the other side of the center C of the rotating shaft 402; make the first included angle α formed by the connection line between the outer circle of the small pressing wheel 403 and the vertex of the shovel blade 405 and the horizontal plane under the self-weight of the shovel blade assembly 4 be 20 - 21 degrees, as shown in Figure 4-1 .

[0026] 2) After the coiling of the steel coil 5 is completed, if the outer diameter of the steel coil 5 is greater than 1400 mm, lower the first roller 6 and keep the position of the second roller 7 unchanged, so that the height difference H between the first roller 6 and the second roller 7 is 60 - 70 mm; if the outer diameter of the steel coil 5 is less than or equal to 1400 mm, lift the first roller 6 and lower the second roller 7, so that the height difference H between the first roller 6 and the second roller 7 is 110 - 120 mm, as shown in Figure 4-1 .

[0027] 3) The oil cylinder 1 adopts a conventional oil cylinder (i.e., without a servo mechanism). During uncoiling, first control the piston rod 11 of the oil cylinder 1 to fully extend, so that the large swing arm 2 and the insertion arm 3 do not rotate relative to each other and form a second included angle β.

[0028] 4) The rack cylinder 9 drives the large swing arm 2 to rotate downward with the first hinge point A as the center. At this time, the second included angle β remains unchanged, as shown in Figure 4-1 the figure; when the large swing arm 2 approaches the outer circumferential surface of the steel coil, the mechanical stop 8 abuts against the boss 406 to fix the shovel head assembly 4 in place. At this time, the first included angle α remains unchanged, as shown in Figure 4-2 the figure.

[0029] 5) Driven by the rack cylinder 9, the large swing arm 2 continues to rotate downward. The small pressing wheel 403 first contacts the outer circumferential surface of the steel coil 5 and moves downward along the outer circumferential surface of the steel coil 5. The small guide wheel 404 does not contact the surface of the steel coil 5, as shown in Figure 4-3 the figure.

[0030] 6) Driven by the rack cylinder 9, the large swing arm 2 continues to rotate downward. The small guide wheel 404 contacts the outer circumferential surface of the steel coil 5 and moves downward along the outer circumferential surface of the steel coil 5. At this time, the piston rod of the oil cylinder 1 retracts, and the insertion arm 3 rotates relative to the large swing arm 2. The second included angle β and the first included angle α gradually increase, that is, the second included angle > β and the first included angle > α, as shown in Figure 4-4 and Figure 4-5 the figure, and the uncoiling of the steel coil 5 is completed.

[0031] The above are only the preferred embodiments of the present invention, but the present invention is not limited thereto. All equivalent substitutions or equivalent changes made according to the concept and technical solution of the present invention should be covered within the protection scope of the present invention.

Claims

1. A steel coil uncoiling control method for a hot coil box. The uncoiling device of the hot coil box includes a large swing arm, an insertion arm, a rack cylinder, an oil cylinder, a shovel blade assembly, a first roller and a second roller for supporting the steel coil. The large swing arm has a first hinge point driven to rotate by the rack cylinder. One end of the large swing arm and the insertion arm form a second hinge point. The insertion arm can be driven by the oil cylinder to rotate at the second hinge point. The shovel blade assembly is arranged at the other end of the insertion arm. A mechanical stop is also provided at the other end of the insertion arm. The shovel blade assembly includes a shovel blade frame, a rotating shaft located in the middle of the shovel blade frame, a small pressing wheel located on one side of the center of the rotating shaft, a small guide wheel located on the other side of the center of the rotating shaft, and a shovel blade. A boss is provided at the top of the shovel blade frame; characterized in that Perform the following steps: 1) Taking the center of the rotating shaft as the boundary, reduce the weight of the cutter holder on one side of the center of the rotating shaft and increase the weight of the cutter holder on the other side of the center of the rotating shaft by drilling or adding weights; make the first included angle formed by the connecting line between the outer circle of the small idler wheel and the vertex of the cutter and the horizontal plane under the self-weight of the cutter assembly be 20 - 21 degrees; 2) After the coiling of the steel coil is completed, if the outer diameter of the steel coil is greater than 1400 mm, lower the first idler roller and keep the position of the second idler roller unchanged to form a first height difference between the first idler roller and the second idler roller; if the outer diameter of the steel coil is less than or equal to 1400 mm, lift the first idler roller and lower the second idler roller to form a second height difference between the first idler roller and the second idler roller; 3) The oil cylinder adopts an oil cylinder without a servo mechanism. When uncoiling, first control the piston rod of the oil cylinder to fully extend so that the large swing arm and the insertion arm do not rotate relative to each other and form a second included angle; 4) Control the rack cylinder to drive the large swing arm to rotate downward with the first hinge point as the center. At this time, keep the second included angle unchanged. When the large swing arm approaches the outer circumferential surface of the steel coil, the mechanical stop block abuts against the boss to make the cutter assembly fixed. At this time, keep the first included angle unchanged; 5) Control the rack cylinder to drive the large swing arm to continue rotating downward. The small idler wheel first contacts the outer circumferential surface of the steel coil and moves downward along the outer circumferential surface of the steel coil, and the small guide wheel does not contact the surface of the steel coil; 6) Control the rack cylinder to drive the large swing arm to continue rotating downward. The small guide wheel contacts the outer circumferential surface of the steel coil and moves downward along the outer circumferential surface of the steel coil. At this time, the piston rod of the oil cylinder retracts, the insertion arm rotates relative to the large swing arm, and the second included angle and the first included angle gradually increase to complete the uncoiling of the steel coil.

2. The coil uncoiling control method of the hot coil box according to claim 1, characterized in that: The first height difference is 60 - 70 mm, and the second height difference is 110 - 120 mm.

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