A new method to improve the yield rate of leveling mill

Abstract

The present invention relates to the field of strip cold rolling technology, specifically to a new method for improving the yield rate of a leveling machine. The present invention installs a steel coil on an unwinder, and pulls out one end of the steel strip, passes through an inlet tension roller group, a leveling machine, an outlet tension roller group in sequence, and is finally fixedly connected to the reel of a coiler; when the diameter of the steel coil on the unwinder is less than 680 mm, the unwinder is manually decelerated to 400 m / min in advance; when the steel strip is completely separated from the coil core of the coiler and the tail of the steel strip reaches the position of the inlet tension roller group, the machine is immediately manually stopped, and the roller gap of the leveling machine is opened to more than 50 mm; the steel strip is cut by a slitting shear, and finally the remaining steel strip is rolled up by a coiler. The present invention reduces the tail swing speed manually in advance, and cuts the steel strip when the tail of the steel strip reaches the inlet tension roller group, thereby reducing the length of the scrap steel strip, which is beneficial to reducing product losses and improving product yield rate.

Description

Technical Field

[0001] The invention relates to the technical field of strip steel cold rolling, in particular to a new method for improving the yield rate of a flattening unit. Background Art

[0002] At present, the market competition for cold-rolled products is fierce, and cost control is particularly important. Among them, reducing product losses and improving product yields are very necessary cost-reduction measures. Usually, when the leveling unit rolls to the tail of the steel coil, due to the poor plate shape of the incoming steel coil core after annealing, damage to the overhead crane clamp, and loss of tension at the tail of the strip that cannot be rolled normally, it is necessary to use a slitting shear at the exit to shear, and then reversely rewind to the unwinder to unload the small coil as waste. The inner diameter of the incoming steel coil produced by the leveling machine is usually 610mm. In order to ensure normal tail swinging, the tail swinging diameter is set to 612mm. In this way, normal and defect-free steel strips of more than 10 meters will be treated as waste, resulting in unnecessary product losses. In order to solve the above problems and improve the yield rate of the unit, we proposed a new method to improve the yield rate of the leveling unit to solve the above disadvantages well. Summary of the invention

[0003] The object of the present invention is to provide a new method for improving the yield of a leveling machine, so as to solve the problems raised in the above-mentioned background technology.

[0004] The present invention is realized by the following technical scheme: a new method for improving the yield of a leveling machine group, comprising the following steps:

[0005] S1: Install the steel coil on the uncoiler, and pull out one end of the steel strip through the inlet tension roller group, the leveler, the outlet tension roller group, the slitting shear, and finally fixedly connected to the reel of the coiler;

[0006] S2: Adjust the coil tail diameter of the uncoiler from 612mm to 609mm, and set the rolling speed of the skin pass mill not to exceed 25m / min when the coil diameter is less than 630mm;

[0007] S3: Start the uncoiler, the skin pass mill and the coiler, and use the skin pass mill to roll the steel coil;

[0008] S4: When the diameter of the steel coil on the uncoiler is less than 680 mm, the unloading speed of the steel strip on the uncoiler is manually reduced to 400 m / min in advance;

[0009] S5: When the steel strip is completely separated from the coil core of the unwinder and the tail of the steel strip reaches the position of the inlet tension roller group, the machine is stopped manually immediately and the roller gap of the leveling machine is opened to more than 50mm;

[0010] S6: Cut the steel strip with a slitting shear, and finally use a coiler to wind up the remaining steel strip;

[0011] Preferably, between S4 and S5, the following steps are also included:

[0012] S4-1: When the diameter of the steel coil on the uncoiler reaches 612mm, the uncoiler, leveler and coiler are manually shut down, and the quality of the steel strip is checked;

[0013] S4-2: If the quality inspection is qualified, the rolling speed of the leveler is set to 10 m / min, and then the leveler, uncoiler and coiler are started again; if the quality inspection is unqualified, that is, an abnormality is found at the tail of the steel strip, the steel strip is cut off by a slitting shear, and then the uncoiler is started in reverse, the unqualified steel strip is reeled on the uncoiler and treated as scrap.

[0014] Preferably, the free end of the steel strip is fixed to the reel of the coiler by welding, and the number of welding points is no more than 6.

[0015] Preferably, a waste winding machine is further provided between the inlet tension roller group and the leveling machine, and after S6 is completed, the following steps are further included:

[0016] S6-1: fixedly connecting one end of the steel belt between the slitting shear and the inlet tension roller group to the reel of the scrap winder;

[0017] S6-2: Start the scrap winder, use the scrap winder to wind up the remaining scrap steel strip, and fix the free end of the scrap steel strip on the reel of the scrap winder.

[0018] Preferably, the steel strip is connected to the scrap winder reel by welding, and the number of welding points is no more than 6.

[0019] Compared with the prior art, the present invention provides a new method for improving the yield rate of a leveling unit, which has the following beneficial effects:

[0020] 1. The present invention reduces the tail-swinging speed manually in advance and cuts off the steel strip when the tail of the steel strip reaches the inlet tension roller group, thereby reducing the length of the waste steel strip, which is beneficial to reducing product losses and improving product yield rate;

[0021] 2. The present invention is provided with a scrap winding machine between the leveling machine and the inlet tension roller group, which can conveniently wind up the scrapped steel strip, thereby helping to improve the scrap winding efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a layout diagram of the equipment related to the leveling machine unit of the present invention.

[0023] In the figure: 1. Unwinder; 2. Inlet tension roller group; 3. Scrap winder; 4. Leveler; 5. Outlet tension roller group; 6. Slitting shear; 7. Coiler. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example: See Figure 1 A new method for improving the yield rate of a leveling machine group. The leveling machine group in this embodiment specifically includes the following equipment: an uncoiler 1, an inlet tension roller group 2, a leveling machine 4, an outlet tension roller group 5, a slitting shear 6 and a coiler 7.

[0026] This embodiment includes the following steps when implemented:

[0027] S1: Install the steel coil on the uncoiler 1, and pull out one end of the steel strip and pass it through the inlet tension roller group 2, the leveler 4, the outlet tension roller group 5, the slitting shear 6 in sequence, and finally fix it to the reel of the coiler 7; it is worth mentioning that when installing the steel coil on the uncoiler 1, it is necessary to use a crane to lift the steel coil, and it is necessary to keep the crane hook head aligned with the coil core to avoid the coil core from being welded and affecting the subsequent insertion of the core shaft; in addition, the free end of the steel strip is fixed to the reel of the coiler 7 by welding, and the number of welding points shall not exceed 6;

[0028] S2: adjusting the tail diameter of the steel coil of the uncoiler 1 from 612 mm to 609 mm, and setting the rolling speed of the skin pass mill 4 not to exceed 25 m / min when the diameter of the steel coil is less than 630 mm;

[0029] S3: start the uncoiler 1, the leveler 4 and the coiler 7, and use the leveler 4 to roll the steel coil;

[0030] S4: When the diameter of the steel coil on the uncoiler 1 is less than 680 mm, the unloading speed of the steel strip of the uncoiler 1 is manually reduced to 400 m / min in advance;

[0031] S4-1: When the diameter of the steel coil on the uncoiler 1 reaches 612 mm, the uncoiler 1, the leveler 4 and the coiler 7 are manually closed, and the quality of the steel strip is checked;

[0032] S4-2: If the quality inspection is qualified, the rolling speed of the leveler 4 is set to 10 m / min, and then the leveler 4, the uncoiler 1 and the coiler 7 are started again; if the quality inspection is unqualified, that is, an abnormality is found at the tail of the steel strip, the steel strip is cut by the slitting shear 6, and then the uncoiler 1 is started in reverse, and the unqualified steel strip is wound on the uncoiler 1 and treated as waste;

[0033] S5: On the premise that the quality inspection in S4-2 is qualified, when the steel strip is completely separated from the winding core of the unwinder 1 and the tail of the steel strip reaches the position of the inlet tension roller group 2, the machine is immediately stopped manually, and the roller gap of the leveler 4 is opened to more than 50mm;

[0034] S6: Cut the steel strip using the slitting shear 6, and finally wind up the remaining steel strip using the coiler 7;

[0035] S6-1: A scrap winder 3 is also provided between the inlet tension roller set 2 and the leveler 4. When S6 is completed, one end of the steel strip between the slitting shear 6 and the inlet tension roller set 2 is fixedly connected to the reel of the scrap winder 3;

[0036] S6-2: Start the scrap winder 3, use the scrap winder 3 to wind up the remaining scrap steel strip, and fix the free end of the scrap steel strip on the reel of the scrap winder 3; it is worth mentioning that the connection between the steel strip and the reel of the scrap winder 3 is welding, and the number of welding points is no more than 6.

[0037] With the existing rolling technology, the tail length of each roll of the leveling unit is about 16 meters under normal circumstances; with the rolling technology of this embodiment, the unleveled portion of the steel strip can be controlled within 4 meters, that is, the loss of each roll of steel strip can be reduced by 12 meters on average. According to the steel coil specification of 1.0×1250mm, weight of 20 tons, and length of 2000 meters, the yield rate of each roll can be increased by 12 / 2000=0.6%.

[0038] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0039] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A new method for improving the yield of a leveling machine, characterized in that: The steps include: S1: Install the steel coil on the uncoiler, and pull out one end of the steel strip through the inlet tension roller group, the leveler, the outlet tension roller group, the slitting shear, and finally fixedly connected to the reel of the coiler; S2: Adjust the coil tail diameter of the uncoiler from 612mm to 609mm, and set the rolling speed of the skin pass mill not to exceed 25m / min when the coil diameter is less than 630mm; S3: Start the uncoiler, the skin pass mill and the coiler, and use the skin pass mill to roll the steel coil; S4: When the diameter of the steel coil on the uncoiler is less than 680 mm, the unloading speed of the steel strip on the uncoiler is manually reduced to 400 m / min in advance; S5: When the steel strip is completely separated from the coil core of the unwinder and the tail of the steel strip reaches the position of the inlet tension roller group, the machine is stopped manually immediately and the roller gap of the leveling machine is opened to more than 50mm; S6: Use the slitting shear to cut the steel strip, and finally use the coiler to wind up the remaining steel strip.

2. A new method for improving the yield of a leveling machine according to claim 1, characterized in that: Between S4 and S5, the following steps are also included: S4-1: When the diameter of the steel coil on the uncoiler reaches 612mm, the uncoiler, leveler and coiler are manually shut down, and the quality of the steel strip is checked; S4-2: If the quality inspection is qualified, the rolling speed of the leveler is set to 10 m / min, and then the leveler, uncoiler and coiler are started again; if the quality inspection is unqualified, that is, an abnormality is found at the tail of the steel strip, the steel strip is cut off by a slitting shear, and then the uncoiler is started in reverse, the unqualified steel strip is reeled on the uncoiler and treated as scrap.

3. A new method for improving the yield of a leveling unit according to claim 1, characterized in that: The free end of the steel strip is fixed to the reel of the coiler by welding, and the number of welding points is no more than 6.

4. A new method for improving the yield of a leveling unit according to claim 1, characterized in that: A waste winding machine is also provided between the inlet tension roller group and the leveling machine. When S6 is completed, the following steps are also included: S6-1: fixedly connecting one end of the steel belt between the slitting shear and the inlet tension roller group to the reel of the scrap winder; S6-2: Start the scrap winder, use the scrap winder to wind up the remaining scrap steel strip, and fix the free end of the scrap steel strip on the reel of the scrap winder.

5. A new method for improving the yield of a leveling unit according to claim 4, characterized in that: The steel belt is connected to the scrap winder reel by welding, and the number of welding points is no more than 6.

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