Control method for preventing tail of hot-rolled thin strip steel from being rubbed

Abstract

The invention discloses a control method for preventing the tail of hot-rolled thin strip steel from being rubbed, which belongs to the technical field of steel rolling, and comprises the following steps: in the use process of a coiling pinch roll, controlling the ovality within 40 microns, and immediately replacing the pinch roll when the ovality exceeds 40 microns; the pinch roll is controlled to be cooled, in the cooling process, it is guaranteed that the pinch roll is in a rotating mode, and the speed is not lower than 1 m / s; controlling the cooling time of the pinch roll, wherein the single cooling time of the pinch roll is not less than 25s; tension control is conducted, and the coiling tension setting coefficient is set to be 0.55; the pinch roll bears load setting, and the load bearing coefficient of the pinch roll is 0.5; and the thickness of the hot-rolled thin strip steel is not greater than 3.0 mm. By adopting the technical scheme, the difficulty that the tail part of the hot-rolled thin strip steel is rubbed and damaged in the production process of the hot-rolled strip steel is solved by optimizing and adjusting process parameters and program control.

Description

Technical Field

[0001] The invention belongs to the technical field of steel rolling, and in particular relates to a control method for preventing the tail of hot-rolled thin strip steel from being scratched. Background Art

[0002] During the operation of the hot rolling production line, when thin-gauge rolling is carried out, due to the relatively fast rolling speed, when the tail of the strip is coiled after the finishing mill is cast, the tension of the strip is mainly borne by the interaction between the coiling pinch roller and the reel. However, in this process, the coiling operation of the tail of the strip is prone to a quality defect, namely, tail rubbing. This rubbing defect is mainly caused by the uneven wear of the pinch roller during long-term use. In addition, the uneven cooling process of the pinch roller will also cause its shape to become irregular and present an elliptical shape. When the pinch roller needs to bear the coiling tension after the finishing mill is cast, the tail coiling tension will be unstable due to the ellipticity of the pinch roller. This unstable tension will cause rubbing on the surface of the strip during the coiling process.

[0003] When the tail of the strip is scratched, it will seriously affect the product quality of the strip. According to the specific position where the pinch roller bears the tension, the distance of the scratch is usually between 130 meters and 140 meters at the tail of the strip. Once the strip has this kind of scratch quality defect, users will not be able to use these strips normally. Since the scratch quality defect is not easy to be found during the production process, this not only seriously affects the customer's experience, but also brings different degrees of economic losses to the company. Therefore, in order to ensure product quality and reduce economic losses, companies need to strictly monitor and manage the wear and cooling process of the pinch rollers to avoid the production of irregular elliptical pinch rollers, thereby reducing the occurrence of scratches at the tail of the strip. Summary of the invention

[0004] The purpose of the present invention is to provide a control method for preventing the tail of hot-rolled thin strip from being rubbed. By formulating a set of detailed actual ovality standards for the coiling and pinching rollers, the quality of the pinching rollers can be more accurately controlled. In addition, by adjusting the cooling time of the coiler pinching rollers and the speed during the cooling process, the deformation of the pinching rollers caused by uneven cooling can be effectively reduced. In order to further optimize this process, a series of measures are also required, such as adjusting the coiling tension coefficient and the coefficient of the load borne by the pinching rollers during tail coiling. These comprehensive improvement measures work together to successfully solve the problem of tail rubbing of thin-gauge hot-rolled strip steel, thereby stabilizing product quality and ensuring efficient and reliable production.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A control method for preventing the tail of hot-rolled thin strip from being scratched, including:

[0007] When using the winding pinch roller, control the ovality within 40μm. If it exceeds 40μm, replace the pinch roller immediately.

[0008] Pinch roller cooling control: during the cooling process, ensure that the pinch roller is in rotation mode and the speed is not less than 1m / s;

[0009] Pinch roller cooling time control, the single cooling time of pinch roller shall not be less than 25s;

[0010] Tension control, the winding tension setting coefficient is set to 0.55;

[0011] The pinch roller load is set, and the pinch roller load factor is 0.5.

[0012] Preferably, the thickness of the hot-rolled thin strip steel is not greater than 3.0 mm.

[0013] Preferably, the single cooling time of the pinch roller is 25s, 30s or 35s.

[0014] Preferably, the speed of the pinch roller during cooling is 1 m / s, 2 m / s or 3 m / s.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The present invention ensures the accuracy and stability of the pinch rollers by formulating a detailed set of actual ovality standards for the coiling pinch rollers. The problem of pinch roller deformation caused by uneven cooling is effectively reduced by accurately adjusting the cooling time and cooling speed of the coiler pinch rollers. In addition, the present invention also involves a series of measures, including adjusting the coiling tension coefficient and the coefficient of the load borne by the pinch rollers during tail coiling, etc. These measures work together to successfully solve the problem of tail rubbing of thin-gauge hot-rolled strips, thereby stabilizing product quality.

[0017] The present invention is not only applicable to the production of various conventional strip steel processes using hot rolling mills, but also greatly expands its application range by optimizing relevant procedures and carefully adjusting process parameters. This optimization and adjustment enables the present invention to have a wide range of technical radiation capabilities and to adapt to different production environments and requirements. At the same time, the present invention provides important technical support for the development of hot-rolled product specifications and injects new vitality into the development of related industries. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of a preferred embodiment of the present invention.

[0019] In the figure: 1. Finishing support roll; 2. Finishing working roll; 3. Heat output roller; 4. Heat inspection equipment; 5. Coiler inlet side guide plate; 6. Upper pinch roll; 7. Lower pinch roll; 8. Auxiliary coiling roll; 9. Strip steel; 10. Reel; 11. Upper pinch roll cooling water circuit; 12. Lower pinch roll cooling water circuit. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. All other embodiments obtained by ordinary technicians in the field without making creative work based on the embodiments of the present invention shall fall within the scope of protection of the present invention.

[0021] like Figure 1 As shown:

[0022] The equipment for hot-rolled thin strip steel mainly includes: loading section, unloading section and coiling section; among which:

[0023] The feeding part includes a finishing support roll 1 and a finishing working roll 2; the finishing support roll 1 includes two upper and lower support rolls; the finishing working roll 2 includes two upper and lower working rolls; the strip steel 9 is sandwiched between the two working rolls;

[0024] The unloading part includes an upper pinch roller 6 and a lower pinch roller 7; an upper pinch roller cooling water channel 11 is provided on one side of the upper pinch roller 6, and a lower pinch roller cooling water channel 12 is provided on one side of the lower pinch roller 7;

[0025] A hot output roller 3 is arranged between the loading part and the unloading part. When working, the strip steel 9 passes through the upper surface of the hot output roller 3.

[0026] The winding section includes a winding drum 10 and an auxiliary winding roller 8;

[0027] A coiler inlet side guide plate 5 and a heat detection device 4 are arranged above the strip steel 9 at the inlet of the unloading section;

[0028] In this embodiment, the thickness of the hot-rolled thin strip steel is not greater than 3.0 mm.

[0029] The strip tail coiling tension is established between the upper pinch roller 6 , the lower pinch roller 7 and the reel 10 .

[0030] In the hot rolling production line, the coiling process plays a vital role. This process involves conveying the strip steel with a certain thickness obtained after rolling in the finishing mill through the hot output roller, and finally rolling it into a hot rolled steel coil under the action of the coiler. The entire coiling process is Figure 1 A detailed display is given in .

[0031] Specifically, the strip rolled out of the last stand of the finishing mill will be transported to the coiling area through the hot output roller. Before the head of the strip is about to enter the coiler, the speed of the hot output roller and the pinch roller, auxiliary coiling roller and reel on the coiler will be set faster than the rolling speed of the last stand. This design is to prevent the strip from being pulled up or piled up on the hot output roller. In order to ensure the accuracy of the strip position, the thermal inspection equipment will monitor the actual position of the strip in real time. The head of the strip will pass through the guide plate and pinch roller on the inlet side of the coiler in turn, and under the action of the auxiliary coiling roller, the strip will be smoothly rolled around the reel into a coil. When the strip is threaded in the coiler, the hot output roller, pinch roller, auxiliary coiling roller and reel will rotate at the same speed as the finishing mill. At this time, the strip forms tension between the reel and the last stand of the finishing mill to achieve coiling.

[0032] When the tail of the strip leaves the last stand, the speed of the hot output roller and the pinch roller needs to lag behind the coiling speed of the coiler. In this case, the tension of the strip coiling is mainly maintained by the tension between the drum and the pinch roller. In order to ensure the stability of the tail of the strip after entering the coiler, when the tail of the strip is about to reach the coiler, the main command speed of the coiling will begin to gradually decelerate until the tail of the strip completely enters the coiler and stops. In addition, in order to ensure that the coiler pinch roller will not have an adverse effect on the roll shape of the strip when it is affected by the high temperature of the strip, after the coiling is completed, the cooling water of the upper and lower pinch rollers will be turned on by the control of the electromagnetic plug to effectively cool the pinch rollers.

[0033] A control method for preventing the tail of hot-rolled thin strip from being scratched, including:

[0034] During the use of the winding pinch roller, there are strict requirements for the control standard of ovality. Specifically, the ovality of the pinch roller must be controlled within 40μm. Once the measurement result exceeds this range, the pinch roller must be replaced immediately to ensure the normal operation of the equipment and the stability of product quality.

[0035] In addition, the cooling control of the pinch roller is also a very important part of the production process. In order to ensure the uniformity of the cooling of the pinch roller, it is necessary to ensure that the pinch roller is in rotation mode during the cooling process. At the same time, in order to ensure the cooling effect, the rotation speed of the pinch roller during cooling shall not be less than 1 meter per second. For example, the speed of the pinch roller during cooling is 1m / s, 2m / s or 3m / s. Such measures help prevent the pinch roller from deforming due to excessive temperature, thereby affecting production efficiency and product quality.

[0036] There are also clear requirements for the cooling time control of the pinch rollers. In order to minimize the impact of the pinch roller temperature on the roller shape, the single cooling time of the pinch roller shall not be less than 25 seconds. For example, the single cooling time of the pinch roller is 25s, 30s or 35s. This measure helps to maintain the stability and durability of the pinch rollers, thereby improving production efficiency and product quality.

[0037] In terms of tension control, the winding tension setting coefficient is set to 0.55. This setting aims to minimize the winding tension while ensuring the roll shape. In this way, the wear of the equipment can be effectively reduced, the service life of the equipment can be extended, and the production efficiency and product quality can be improved.

[0038] Finally, in terms of the load setting of the pinch roller, the load coefficient of the pinch roller was adjusted from the original 0.6 to 0.5. The purpose of this adjustment is to reduce the tension borne by the tail pinch roller, thereby reducing the load on the equipment and extending the service life of the equipment. At the same time, this measure also helps to improve production efficiency and product quality.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A control method for preventing the tail of hot-rolled thin strip from being scratched, characterized in that: include: When using the winding pinch roller, control the ovality within 40μm. If it exceeds 40μm, replace the pinch roller immediately. Pinch roller cooling control: during the cooling process, ensure that the pinch roller is in rotation mode and the speed is not less than 1m / s; Pinch roller cooling time control, the single cooling time of pinch roller shall not be less than 25s; Tension control, the winding tension setting coefficient is set to 0.55; The pinch roller load is set, and the pinch roller load factor is 0.

5.

2. A control method for preventing the tail of hot-rolled thin strip from being scratched according to claim 1, characterized in that: The thickness of hot rolled thin strip steel shall not exceed 3.0 mm.

3. A control method for preventing the tail of hot-rolled thin strip from being scratched according to claim 1, characterized in that: The single cooling time of the pinch roller is 25s, 30s or 35s.

4. A control method for preventing the tail of hot-rolled thin strip from being scratched according to claim 1, characterized in that: The speed of the pinch roller during cooling is 1 m / s, 2 m / s or 3 m / s.

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