A strip break handling method for a single stand reversing mill

Abstract

The application discloses a strip breaking treatment method of a single-stand reversing rolling mill, and when the thin strip coil and the thick strip coil are both rollable and the residual rolling pass number of the thin strip coil is even or only the thin strip coil is rollable, the strip head of the thin strip coil is threaded, and the strip head of the thin strip coil after threading is overlapped with the strip tail of the thick strip coil; the corresponding mandrel of the thick strip coil is controlled to be wound, and the corresponding mandrel of the thin strip coil is controlled to be unwound, so that the strip head of the thin strip coil is wound on the thick strip coil; the thin strip coil is rolled, and after the rolling of the thin strip coil is completed, the rolled thin strip coil is unloaded to obtain a first finished steel coil; and if the thick strip coil is rollable, the strip head of the thick strip coil is threaded to the mandrel on the outlet side to be curled and tensioned, the thick strip coil is rolled to obtain a second finished steel coil, and the unloaded thick strip coil and the thin strip coil strip head tail winding re-cutting operation are not needed, so that the accident treatment time is shortened, and the yield is effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of strip steel production, in particular to a strip breakage processing method of single stand reversing mill. BACKGROUND

[0002] In recent years, the total output of cold-rolled sheet in China increases year by year, and thin-gauge, high-value-added special plates are increasingly favored by enterprises. With the continuous increase of thin-gauge strip steel production capacity, the strip breakage rate of thin strip steel is also gradually rising. How to quickly handle strip breakage accidents and shorten downtime has become a problem that enterprises need to solve urgently.

[0003] As a type of single stand reversing mill, the 20-roll mill has the characteristics of large mill stiffness, small work roll diameter, high control precision, and has become the main mill for rolling thin strip steel in various cold rolling enterprises. However, due to the compact layout of the 20-roll mill and the small operating space, it is difficult to handle the breakage accident, which takes a long time. Especially when handling the breakage accident of ultra-thin strip steel below 0.3mm, the strip steel is thin, the threading process is frequently blocked, and manual traction is required, which increases the risk of personnel operation and affects the effective operation rate of the mill.

[0004] In summary, the prior art has the technical problems of long processing time after strip breakage and low material utilization rate. SUMMARY

[0005] To solve the above technical problems, the present application provides a strip breakage processing method of single stand reversing mill, which effectively shortens the strip breakage processing time and the steel strip yield, and can effectively solve the technical problem of difficult secondary threading of strip steel.

[0006] The scheme for achieving the technical purpose of the present application is a strip breakage processing method of single stand reversing mill, comprising the following steps:

[0007] determine whether the thin strip sub-roll and the thick strip sub-roll formed by the broken strip of the rolling strip steel coil have rollability;

[0008] when the determination result is that both the thin strip sub-roll and the thick strip sub-roll have rollability and the remaining rolling times of the thin strip sub-roll are even, or when the determination result is that only the thin strip sub-roll has rollability, then:

[0009] thread the strip head of the thin strip sub-roll, and overlap the strip head of the thin strip sub-roll after threading with the strip tail of the thick strip sub-roll; control the winding of the mandrel corresponding to the thick strip sub-roll, and control the unwinding of the mandrel corresponding to the thin strip sub-roll, so that the strip head of the thin strip sub-roll is wound on the thick strip sub-roll;

[0010] The thin strip coil is rolled, and after the thin strip coil is rolled, the rolled thin strip coil is uncoiled to obtain a first finished steel coil; and if the thick strip coil is rollable, the strip head of the thick strip coil is threaded to the outlet side core shaft to be crimped and tensioned, the thick strip coil is rolled, and a second finished steel coil is obtained.

[0011] In some embodiments, the strip head of the thin strip coil is threaded, specifically including:

[0012] The core shaft of the thick strip coil is uncoiled to thread the strip head of the thick strip coil and move to the guide roller on the side where the thin strip coil is located; the thin strip coil is uncoiled and moved forward along the upper surface of the strip steel of the thick strip coil to the guide roller on the opposite side to complete the threading of the thin strip coil.

[0013] In some embodiments, the control of the uncoiling of the thin strip coil and the forward movement along the upper surface of the strip steel of the thick strip coil to the guide roller on the opposite side specifically includes:

[0014] The uncoiling of the thin strip coil is controlled while the core shaft of the thick strip coil is stationary.

[0015] In some embodiments, the single-stand reversing mill strip breakage processing method further includes:

[0016] When the judgment result is that the thin strip coil is not rollable, the thin strip coil is uncoiled, and the strip head of the thick strip coil is conventionally threaded and crimped onto the core shaft on the opposite side, and after tensioning and building, the production is started, the thick strip coil is rolled, and a finished steel coil is obtained.

[0017] In some embodiments, the single-stand reversing mill strip breakage processing method further includes:

[0018] When the judgment result is that the thin strip coil and the thick strip coil are both rollable and the number of remaining rolling passes of the thin strip coil is odd, then,

[0019] The core shaft of the thick strip coil is uncoiled to thread the strip head of the thick strip coil and move to the guide roller on the side where the thin strip coil is located; the thin strip coil is uncoiled and moved forward along the upper surface of the strip steel of the thick strip coil to the guide roller on the opposite side to complete the threading of the thin strip coil.

[0020] The thick strip coil is uncoiled from the core shaft, the thin strip coil is uncoiled and the strip head of the thin strip coil is wound on the core shaft, after tensioning and building, the production is started, the thin strip coil is rolled, and after the rolling is completed to obtain a finished steel coil, the thin strip coil is uncoiled; then the thick strip coil is wound, threaded, crimped and tensioned, and rolled to obtain a finished steel coil.

[0021] In some embodiments, determining whether the thin strip coils and thick strip coils formed by the breakage of the strip coil during rolling are rollable specifically includes:

[0022] The weight and / or length of the thin strip coil are compared with the set rolling parameters of the single-stand reversible rolling mill. If the weight and / or length of the thin strip coil is not less than the corresponding set rolling parameters, then the thin strip coil is rollable.

[0023] The weight and / or length of the thick strip coil are compared with the set rolling parameters of the single-stand reversible rolling mill. If the weight and / or length of the thick strip coil is not less than the corresponding set rolling parameters, then the thick strip coil is rollable.

[0024] In some embodiments, the step of overlapping the head of the thin strip roll with the tail of the thick strip roll after threading specifically includes: the overlap length L1 of the head of the thin strip roll and the tail of the thick strip roll after threading satisfies A / 3≤L1<B; and / or; the step of controlling the mandrel corresponding to the thick strip roll to wind up, and simultaneously controlling the mandrel corresponding to the thin strip roll to unwind, so that the head of the thin strip roll is wound onto the thick strip roll, specifically includes: controlling the rotation speed of the mandrels on both sides so that the overlap length L2 of the thick and thin strips coiled together satisfies A≤L2≤B;

[0025] Where A is the distance between the exit-side guide roller and the inlet-side guide roller, and B is the distance between the two mandrels.

[0026] In some embodiments, controlling the mandrel corresponding to the thick strip spool to take up the winding while simultaneously controlling the mandrel corresponding to the thin strip spool to unwind the winding specifically includes:

[0027] The rotational speeds of the two mandrels are controlled separately to ensure that the running speed of the thick strip being spun is the same as that of the thick strip being spun.

[0028] In some embodiments, before threading the thin strip / thick strip spools, the single-stand reversible rolling mill strip breakage treatment method further includes neatly cutting the strip head of the thin strip / thick strip spools.

[0029] In some embodiments, when the determination result is that both the thin strip coil and the thick strip coil are rollable, the single-stand reversible rolling mill strip breakage treatment method further includes transferring the two finished steel coils obtained by the thin strip coil and the thick strip coil rolling processes sequentially to the welding unit, and welding the two finished steel coils into a whole coil by the welding unit.

[0030] As can be seen from the above technical solution, the present invention provides a method for handling strip breakage in a single-stand reversible rolling mill, comprising the following steps:

[0031] Determine whether the thin strip coils and thick strip coils formed by strip breakage during rolling are rollable, so as to determine the subsequent treatment plan;

[0032] When the determination result is that both the thin strip coil and the thick strip coil are rollable and the remaining number of rolling passes for the thin strip coil is even, or when the determination result is that only the thin strip coil is rollable, then:

[0033] The thin strip roll is threaded onto the head of the thin strip roll, and the threaded head of the thin strip roll overlaps with the tail of the thick strip roll; the mandrel corresponding to the thick strip roll is controlled to wind up, while the mandrel corresponding to the thin strip roll is controlled to unwind, so that the head of the thin strip roll is wound onto the thick strip roll.

[0034] The thin strip coil is rolled. After the thin strip coil is rolled, it is unwound to obtain the first finished steel coil. If the thick strip coil is rollable, the rolled thin strip coil is separated from the thick strip coil, and the thick strip coil is still wound on the mandrel on the inlet side, eliminating the need for unwinding and rewinding the thick strip coil. The end of the thick strip coil is then threaded onto the mandrel on the outlet side for coiling and tensioning, and rolled to obtain the second finished steel coil.

[0035] Since the thick strip coil is not rollable when it is not, it will not be rolled further. In the prior art, the thick strip coil is usually unwound directly, and the thin strip coil is then subjected to subsequent threading, winding, tensioning, and rolling operations. Alternatively, when both the thin and thick strip coils are rollable and the remaining number of rolling passes for the thin strip coil is even, the thick strip coil is wound onto the mandrel on the entrance side. After the thin strip coil passes through an even number of rolling passes and exits, it remains on a different side from the thick strip coil. In this case, the curling of the thick and thin strip coils will not affect each other. To improve the rolling yield of thin strip coils, this application, through analysis, found that in the two situations mentioned above, the coiling of the thick strip on the mandrel does not affect the winding and threading of the thin strip coil. Therefore, the two judgment results can be handled manually using the same method. By overlapping the end of the thin strip coil after threading with the thick strip coil, the effect of the thick strip wrapping the thin strip is achieved. Furthermore, when winding and tensioning the thin strip coil, the thickness of the thick strip coil wound on the mandrel can be used to reduce the length of the tail coil of the thin strip coil compared to a single coil. The solution of separately winding thin strip onto the mandrel avoids unwinding the thick strip and directly wraps the thin strip around it. This allows the thin strip to be wound a shorter distance to reach the diameter of the steel coil required for mandrel expansion. This avoids the problem of needing to wind the strip a long distance to compensate for the fan-shaped gap caused by mandrel expansion. It also avoids the traditional operation of unwinding the thick strip and cutting off the beginning and end of the thin strip, shortening the accident handling time and effectively improving the rolling yield of the thin strip. Attached Figure Description

[0036] Figure 1 This is a flowchart;

[0037] Figure 2 This is a schematic diagram of a 20-roll mill unit;

[0038] Figure 3 This is a schematic diagram showing the overlap between the thick strip and the thin strip after the thick strip is sewn and threaded.

[0039] Figure 4 A schematic diagram illustrating the threading process of the tape head, which assists in the slitting of thinner tape for thicker tape.

[0040] Figure 5 A schematic diagram of thin strip wrapping thick strip.

[0041] Explanation of reference numerals in the attached diagram: 10 - thin strip rewinding; 20 - thick strip rewinding;

[0042] 30 - Twenty-roll mill unit, 31 - Guide roll, 32 - Plate shaper roll, 33 - Wiping roll, 34 - Mill, 35 - Mandrel. Detailed Implementation

[0043] To enable those skilled in the art to better understand this application, the technical solution of this application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] To address the technical problems of long strip breakage processing time and low material utilization in existing technologies, this invention provides a strip breakage processing method for a single-stand reversible rolling mill. This method effectively shortens the strip breakage processing time and increases the strip yield, while also effectively solving the technical problem of difficulty in secondary strip threading. The following detailed description of this invention is provided through a specific embodiment:

[0045] Example

[0046] like Figure 1 As shown in the figure, this embodiment provides a method for handling strip breakage in a single-stand reversible rolling mill, which includes the following steps:

[0047] Determine whether the thin strip coils and thick strip coils formed by strip breakage during rolling are rollable, so as to determine the subsequent treatment plan;

[0048] When the judgment result is that both thin strip coils and thick strip coils are rollable and the remaining number of rolling passes for the thin strip coil is even, or when the judgment result is that only the thin strip coil is rollable, then:

[0049] Thread the tape head of the thin strip into the thick strip and overlap the tape tail of the thin strip into the thick strip; control the winding of the mandrel corresponding to the thick strip into the thick strip and simultaneously control the unwinding of the mandrel corresponding to the thin strip into the thick strip into the thick strip.

[0050] Thin strip coils are rolled. After rolling, the thin strip coils are unwound to obtain the first finished steel coil. If the thick strip coils are rollable, the rolled thin strip coils are separated from the thick strip coils, while the thick strip coils remain wound on the mandrel at the entrance, eliminating the need for unwinding and rewinding. The end of the thick strip coil is then threaded onto the mandrel at the exit side for tensioning and rolling to obtain the second finished steel coil.

[0051] Since the thick strip coil is not rollable when it is not rolled, the existing technology often directly unwinds the thick strip coil and performs subsequent operations such as threading, winding, tensioning, and rolling on the thin strip coil. Alternatively, when both the thin and thick strip coils are rollable and the remaining rolling passes of the thin strip coil are even, the thick strip coil is wound onto the mandrel on the entrance side. After the thin strip coil passes through an even number of rolling passes and exits, it remains on a different side from the thick strip coil. In this case, the curling of the thick and thin strip coils will not affect each other. To improve the rolling yield of thin strip coils, this application, through analysis, found that in the two situations mentioned above, the thick strip coil curling on the mandrel does not affect the winding and threading of the thin strip coil. Therefore, the two judgment results can be handled manually using the same method: by overlapping the end of the thin strip coil after threading with the thick strip coil, the thick strip steel can wrap around the thin strip steel. Furthermore, when winding and tensioning the thin strip coil, the thickness of the thick strip coil wound on the mandrel can be used to reduce the length of the tail coil of the thin strip coil, compared to simply winding the thin strip coil separately onto the mandrel. The above solution, by not uncoiling the thick strip and directly wrapping the thin strip on top of the thick strip, only requires winding the thin strip a shorter distance to reach the steel coil diameter required for mandrel expansion. This avoids the problem of needing to wind the strip a long distance to compensate for the large gaps caused by the fan-shaped plate due to mandrel expansion. While ensuring that no wrinkles or collapses occur during the winding process, it also avoids the uncoiling of the thick strip and the re-cutting of the head and tail of the thin strip in traditional operations, shortening the accident handling time and effectively improving the rolling yield of the thin strip.

[0052] It should be noted that the method for determining thin strip splitting and thick strip splitting in this embodiment is based on the comparison of the thickness of the strip after the strip is broken. Since it is a single-stand reversible rolling mill, the strip coiled on the two mandrels after the strip is broken will inevitably have one of the strips rolled more times, and thus its thickness will be thinner, rather than being defined by the thickness of the strip.

[0053] This embodiment does not specifically limit the application scenario; it can be applied to broken strip steel with a thickness greater than 0.3mm, as well as to broken strip steel accidents with a thickness less than 0.3mm. Because strip steel thicknesses below a certain value are prone to jamming during the threading process, and the frequency of jamming is high, to avoid the safety issues and other problems associated with manual traction, as a preferred implementation method, threading the strip head of the thin strip coil is performed, specifically including:

[0054] Controlling the unwinding of the mandrel in the thick strip spool allows the strip head of the thick strip spool to be threaded and moved to the guide roller on the side where the thin strip spool is located. Controlling the unwinding of the thin strip spool also allows it to move forward along the upper surface of the thick strip spool to the guide roller on the opposite side, completing the threading of the thin strip spool. In other words, the thicker thick strip spool, which may even require no manual threading, paves the way for the strip head of the thin strip spool. This restricts the position of the strip head of the thin strip spool and acts as a guide, allowing the strip head of the thin strip spool to be threaded smoothly without the need for manual traction. This effectively avoids accidents, solves the problem of threading jams, shortens accident handling time, ensures the safety of operators, and improves the efficiency of the rolling mill.

[0055] This embodiment does not specifically limit the threading speed or process of the thin strip spool, and can be adapted to meet actual needs. As one implementation method, controlling the thin strip spool to unwind and move forward along the upper surface of the thick strip spool to the opposite guide roller specifically includes: controlling the thin strip spool to unwind while simultaneously keeping the mandrel of the thick strip spool stationary to stably maintain the movement of the thin strip spool's lead. Of course, in other implementations, the thin and thick strip spools can move relative to each other, as long as the lead of the thin strip spool is always positioned on the thick strip spool and moves forward along it before threading is completed. Here, "moving forward" refers to moving from the current side to the opposite mandrel.

[0056] In this embodiment, the strip breakage handling method for a single-stand reversible rolling mill further includes: when the judgment result indicates that the thin strip coil is not rollable, the thin strip coil is unwound, and the strip head of the thick strip coil is conventionally threaded and wound onto the opposite mandrel. After coiling and tensioning, production begins to complete the thick strip coil rolling, resulting in a finished steel coil. Of course, in some embodiments, after the thick strip coil is threaded and moved to the opposite mandrel, the above-mentioned thin strip coil handling method can be used, i.e., the thin strip is used to wrap the thick strip during coiling to improve the yield of the thick strip coil. However, when the thickness of the thin strip coil is low, and the overall coil thickness is also low, the yield improvement achieved by thin strip coiling is also low. The solution can be selected according to actual needs; this embodiment does not impose specific limitations.

[0057] In this embodiment, the strip breakage handling method for a single-stand reversible rolling mill further includes: when the judgment result is that both the thin strip coil and the thick strip coil are rollable and the remaining rolling passes of the thin strip coil are odd, then, the mandrel of the thick strip coil is uncoiled so that the strip head of the thick strip coil is threaded through and moved to the guide roller on the side where the thin strip coil is located; the thin strip coil is uncoiled and moved forward along the upper surface of the strip of the thick strip coil to the guide roller on the opposite side to complete the threading of the thin strip coil, that is, the strip head of the thin strip coil is threaded through with the assistance of the strip of the thick strip coil. However, since the thick strip coil is located on the exit side at this time, for example, when the thin strip coil has one rolling pass remaining, if the above-mentioned thin strip wrapping thick strip scheme is still used, the thin strip coil will be rolled to the finished product in one pass, and the finished strip will be wrapped around the outer ring of the thick strip coil, making it impossible for the thick strip coil to be directly re-coiled and rolled. Therefore, the wrapping scheme cannot be used for odd-numbered passes. Specifically, after completing the auxiliary threading, the thick strip coil is uncoiled from the mandrel, the thin strip coil is uncoiled and the strip head of the thin strip coil is wound onto the mandrel, and after coiling and tensioning, production is started to roll the thin strip coil and uncoil it after the finished steel coil is obtained. Then the thick strip coil is coiled, threaded, coiled and tensioned and rolled to obtain the finished steel coil.

[0058] In this embodiment, determining whether the thin strip coil and thick strip coil formed by the breakage of the strip coil during rolling are rollable specifically includes: comparing the weight and / or length of the thin strip coil with the set rolling parameters of the single-stand reversible rolling mill; if the weight and / or length of the thin strip coil is not less than the corresponding set rolling parameters, then the thin strip coil is rollable; comparing the weight and / or length of the thick strip coil with the set rolling parameters of the single-stand reversible rolling mill; if the weight and / or length of the thick strip coil is not less than the corresponding set rolling parameters, then the thick strip coil is rollable.

[0059] To improve the yield of thin strip spooling, as one implementation method, the overlap between the head of the thin strip spool and the tail of the thick strip spool after threading is specifically included: the overlap length L1 between the head of the thin strip spool and the tail of the thick strip spool after threading satisfies A / 3≤L1<B; and / or; controlling the winding of the mandrel corresponding to the thick strip spool while simultaneously controlling the unwinding of the mandrel corresponding to the thin strip spool, so that the head of the thin strip spool is wound onto the thick strip spool, specifically including: controlling the rotational speed of the mandrels on both sides so that the overlap length L2 of the coiled thick and thin strips satisfies A≤L2≤B; where A is the distance between the exit-side guide roller and the inlet-side guide roller, and B is the distance between the two mandrels.

[0060] In one preferred embodiment, the mandrel corresponding to the thick strip winding is controlled to wind up, while the mandrel corresponding to the thin strip winding is controlled to unwind. Specifically, this includes controlling the rotational speed of the two mandrels respectively, so that the running speed of the strip in the thick strip winding is the same as that of the strip in the thin strip winding.

[0061] Before threading the thin strip / thick strip into coils, the strip breakage treatment method for single-stand reversible rolling mills also includes neatly cutting the strip ends of the thin strip / thick strip into coils to ensure proper threading of the strip ends and that the dimensions of the strip meet the requirements.

[0062] When the judgment result is that both thin strip coiling and thick strip coiling are rollable, the strip breakage handling method of single-stand reversible rolling mill also includes transferring the two finished steel coils obtained by thin strip coiling and thick strip coiling rolling to the welding unit, and welding the two finished steel coils into a whole coil by the welding unit.

[0063] The following uses a 20-roll mill as an example to illustrate the solution of this application through a specific application example:

[0064] Application Examples

[0065] The composition of the 34th unit of the 20-roll rolling mill is as follows: Figure 2 As shown, after a strip breakage accident occurs in the 30th roll of the 34th unit of the 20-roll mill, the entire strip is divided into two coils of different thicknesses (hereinafter referred to as thin strip coil 10 and thick strip coil 20), which are respectively wound onto the inlet-side mandrel 35 and the outlet-side mandrel 35 (e.g., Figure 3 The operators neatly cut the ends of the two rolls and adopted different handling measures according to the size of the rolls and the unit conditions.

[0066] 1. Thin strip coil 10 is too small (its weight is less than the set rollable weight of the stand) and is not rollable. Thin strip coil 10 is unwound directly. Thick strip coil 20 is threaded in a conventional manner, and after winding and tensioning, production begins to complete the rolling of thick strip coil 20.

[0067] 2. The thick strip coil 20 is too small (same as above) and lacks rollability. This thick strip coil 20 is used to overlap and thread the thin strip coil 10, achieving a "thin strip wrapping thick strip" winding effect. Specifically:

[0068] ① The thick strip coil 20 extends in the reverse direction, passing sequentially through guide roller 31, shape measuring roller 32, wiping roller 33, and rolling mill 34, until it reaches the bottom of the thin strip coil 10, completing the overlap. The strip steel of the thick strip coil 20 "paves" the way for the thin strip coil 10 to pass through (e.g., Figure 3 ).

[0069] ② The strip head of the thin strip coil 10 slides forward on the upper surface of the thick strip steel, passing sequentially through the guide roller 31, the shape measuring roller 32, the wiping roller 33, and the rolling mill 34, completing the strip threading operation and solving the problem of strip head jamming during the thin strip coil 10 threading (e.g. Figure 4 ).

[0070] ③ When the thin strip spool 10 head reaches the area of ​​the opposite guide roller 31, the mandrels 35 on both sides rotate simultaneously. The thin strip spool 10 head enters the thick strip spool 20 along the upper surface of the thick strip. As the mandrel 35 rotates, the thick strip spool 20 is wrapped (e.g., ...). Figure 5 ).

[0071] ④ After the coil is formed, the rolling mill starts production on line 34 and completes the thin strip slitting and rolling process on line 10.

[0072] 3. Both sides of the roll are rollable. Different processing methods are adopted according to the remaining number of passes in the 10 rolls of the thin strip.

[0073] ① The remaining odd number of passes for the thin strip spool 10. Using the "overlapping threading" method 2-①, thread the thin strip spool 10 to the opposite guide roller 31; unwind the thick strip spool 20; after the thin strip spool 10 is wound onto the mandrel 35, it is rolled separately; after the thin strip spool 10 is rolled, it is unwound; the thick strip spool 20 is rewound, threaded, and rolled separately off the production line.

[0074] ② The remaining even-numbered passes for thin strip spool 10. Using the processing methods 2-①, 2-②, 2-③, and 2-④ "thin strip wrapping thick strip", the thin strip spool 10 is wound up and rolled separately; after the thin strip spool 10 is rolled, it is unwound; the thick strip spool 20 is re-threaded, wound up, and rolled off the line separately.

[0075] ③ After both rolls are rolled, they are transported to the welding unit to be welded into a single roll.

[0076] This invention decomposes the traditional strip breakage handling process, which involves single-sided unwinding, repeated threading, tail coil cutting, and secondary winding. It optimizes the operational flow in a targeted manner, solving the threading jamming problem, shortening the accident handling time, ensuring operator safety, and improving the operating efficiency of the 34th mill. Using this invention, the average strip breakage handling time on the single-stand reversible 34th mill for thin strip steel has been reduced from 40 minutes to 25 minutes, saving approximately 15 minutes per accident handling session. No personnel are required to pull the strip during threading, effectively preventing injuries. The number of tail coils to be cut is reduced by one. Based on a tail coil weight of 150 kg and a total coil weight of 18 tons, the overall coil yield is increased by 0.83%, achieving cost reduction and efficiency improvement. This invention has significant economic benefits and is worthy of widespread application.

[0077] This invention mainly uses the "overlapping threading" mode to solve the problem of strip head jamming during the threading of thin strip steel, realizing the threading of thin strip steel strip head without jamming; at the same time, it avoids the traditional operation of unwinding the thick strip spool 20 and cutting off the head and tail of the thin strip spool 10 again, shortening the accident handling time and improving the yield of thin strip spool 10.

[0078] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0079] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for handling strip breakage in a single-stand reversible rolling mill, characterized in that, Includes the following steps: Determining whether the thin and thick strip coils formed by the breakage of the strip during rolling possess rollability specifically includes: The weight and / or length of the thin strip coil are compared with the set rolling parameters of the single-stand reversible rolling mill. If the weight and / or length of the thin strip coil is not less than the corresponding set rolling parameters, then the thin strip coil is rollable. The weight and / or length of the thick strip coil are compared with the set rolling parameters of the single-stand reversible rolling mill. If the weight and / or length of the thick strip coil is not less than the corresponding set rolling parameters, then the thick strip coil is rollable. When the determination result is that both the thin strip coil and the thick strip coil are rollable and the remaining number of rolling passes for the thin strip coil is even, or when the determination result is that only the thin strip coil is rollable, then: The thin strip roll is threaded onto the head of the thin strip roll, and the threaded head of the thin strip roll overlaps with the tail of the thick strip roll; the mandrel corresponding to the thick strip roll is controlled to wind up, while the mandrel corresponding to the thin strip roll is controlled to unwind, so that the head of the thin strip roll is wound onto the thick strip roll. The thin strip coil is rolled, and after the thin strip coil is rolled, it is uncoiled to obtain the first finished steel coil; and if the thick strip coil is rollable, the strip head of the thick strip coil is threaded to the exit side mandrel for coiling and tensioning, and then rolled to obtain the second finished steel coil; The process of threading the tape head of the thin strip roll specifically includes: Controlling the unwinding of the mandrel of the thick strip spool causes the strip head of the thick strip spool to be threaded and moved to the guide roller on the side where the thin strip spool is located; controlling the unwinding of the thin strip spool and moving it forward along the upper surface of the strip of the thick strip spool to the guide roller on the opposite side completes the threading of the thin strip spool.

2. The method for handling strip breakage in a single-stand reversible rolling mill as described in claim 1, characterized in that, The guide roller that controls the unwinding of the thin strip and moves forward along the upper surface of the thick strip to the opposite side specifically includes: While controlling the unwinding of the thin strip, the mandrel of the thick strip is kept stationary.

3. The method for handling strip breakage in a single-stand reversible rolling mill as described in claim 1 or 2, characterized in that, The method for handling strip breakage in a single-stand reversible rolling mill also includes: When the judgment result is that the thin strip coil is not rollable, the thin strip coil is unwound, and the strip head of the thick strip coil is conventionally threaded and wound onto the mandrel on the opposite side. After the coil is tensioned, the machine is started for production to complete the thick strip coil rolling and obtain the finished steel coil.

4. The method for handling strip breakage in a single-stand reversible rolling mill as described in claim 1 or 2, characterized in that, The method for handling strip breakage in a single-stand reversible rolling mill also includes: When the determination result is that both the thin strip coil and the thick strip coil are rollable and the remaining number of rolling passes for the thin strip coil is odd, then... Control the unwinding of the mandrel of the thick strip to allow the strip head of the thick strip to be threaded and moved to the guide roller on the side where the thin strip is located; control the unwinding of the thin strip and move it forward along the upper surface of the strip of the thick strip to the guide roller on the opposite side to complete the threading of the thin strip. The thick strip is unwound from the mandrel, the thin strip is unwound and the strip head is wound onto the mandrel, and after tensioning, the machine is started for production. The thin strip is rolled and unwound after the finished steel coil is obtained. Then the thick strip is wound, threaded, coiled and tensioned and rolled to obtain the finished steel coil.

5. The method for handling strip breakage in a single-stand reversible rolling mill as described in claim 1 or 2, characterized in that, The method of making the tape head of the thin tape roll overlap with the tape tail of the thick tape roll after tape threading specifically includes: the overlap length L1 of the tape head of the thin tape roll and the tape tail of the thick tape roll after tape threading satisfies A / 3≤L1<B; and / or; the method of controlling the mandrel corresponding to the thick tape roll to wind up, and simultaneously controlling the mandrel corresponding to the thin tape roll to unwind, so that the tape head of the thin tape roll is wound onto the thick tape roll, specifically includes: controlling the rotation speed of the mandrels on both sides so that the overlap length L2 of the thick and thin tapes wound together satisfies A≤L2≤B; Where A is the distance between the exit-side guide roller and the inlet-side guide roller, and B is the distance between the two mandrels.

6. The strip breakage treatment method for a single-stand reversible rolling mill as described in claim 5, characterized in that, The control of the mandrel winding corresponding to the thick strip spool and the control of the mandrel unwinding corresponding to the thin strip spool specifically includes: The rotational speeds of the two mandrels are controlled separately to ensure that the running speed of the thick strip being spun is the same as that of the thick strip being spun.

7. The method for handling strip breakage in a single-stand reversible rolling mill as described in claim 1 or 2, characterized in that, Before threading the thin strip / thick strip into the roll, the single-stand reversible rolling mill strip breakage treatment method further includes neatly cutting the strip head of the thin strip / thick strip into the roll.

8. The method for handling strip breakage in a single-stand reversible rolling mill as described in claim 1 or 2, characterized in that, When the judgment result is that both the thin strip coil and the thick strip coil are rollable, the single-stand reversible rolling mill strip breakage treatment method further includes transferring the two finished steel coils obtained by the thin strip coil and the thick strip coil rolling respectively to the welding unit, and welding the two finished steel coils into a whole coil by the welding unit.

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