Stable rolling process for extremely thin special alloy strip

Abstract

The present invention provides a stable rolling process for ultra-thin strips of special alloys, comprising the following steps: obtaining the first-pass steady-state data of all historical rolling processes and constructing a historical first-pass steady-state data feature library; according to the characteristics of the strip to be rolled, retrieving the historical first-pass steady-state data that conforms to the characteristics of the strip to be rolled in the historical first-pass steady-state data feature library, calculating the first-pass rolling process data of the strip to be rolled, starting the rolling mill, and the rolling mill rolling the strip to be rolled according to the first-pass rolling process data; calculating the rolling process data of the next pass of the strip to be rolled according to the rolling process data of the previous pass of the strip to be rolled, and the rolling mill starting the non-first-pass rolling of the strip to be rolled according to the rolling process data of the next pass. The present invention takes the process data on the outlet side of the current pass as the given standard for the process data on the inlet side of the next pass, greatly reducing the length of the head and tail out-of-tolerance sections.

Description

Technical Field

[0001] The invention belongs to the field of plate and strip rolling, and in particular relates to a stable rolling process for ultra-thin strips of special alloys. Background Art

[0002] Strips are widely used in defense, military industry, home appliances, microelectronics and other fields. Especially with the promotion of high-tech electronic products such as curved screens, end users of products require strips to have extremely thin thickness, extremely high strength, excellent plate shape and high conductivity. Therefore, the domestic demand for this kind of special alloy ultra-thin strip is huge, but most of the products currently rely on imports.

[0003] The main reason for this dilemma is that the material properties of special alloys vary greatly, and high hardness, difficulty in deformation and poor ductility are the main characteristics of this type of alloy. In addition, since the requirements for production technology far exceed those of conventional metal materials, the preparation of ultra-thin strips of special alloys is very difficult and there are the following serious problems in actual rolling production:

[0004] (1) Excessive length

[0005] The scarcity of raw materials has resulted in a lack of process data for ultra-thin strips of special alloys. Therefore, production units mostly rely on empirical data and on-site exploration to adjust the thickness and shape of the strips, which causes the strip coils to be scrapped due to excessive head and tail precision. Excessive head and tail tolerances cause waste of expensive materials and seriously affect the stable production of the unit operation line.

[0006] (2) Low yield rate

[0007] Due to poor ductility, extremely high strength and obvious work hardening, special alloy strips often break during the rolling process. This phenomenon greatly reduces the product yield rate, especially in the final production, which will cause huge economic losses. Summary of the invention

[0008] The purpose of the present invention is to provide a stable rolling process for ultra-thin strips of special alloys to overcome the above-mentioned technical defects.

[0009] In order to solve the above technical problems, the present invention provides a stable rolling process for ultra-thin strips of special alloys, comprising the following steps:

[0010] Obtain the first-pass sub-steady-state data of all historical rolling processes and build a feature database of the first-pass sub-steady-state data of history;

[0011] According to the characteristics of the target strip to be rolled, the first pass sub-steady state data feature library is retrieved to obtain the target strip that meets the requirements of the target strip to be rolled.

[0012] The historical first-pass steady-state data of the target strip characteristics are used to calculate the first-pass rolling process data of the target strip to be rolled, and the rolling mill is started, and the rolling mill rolls the target strip to be rolled according to the first-pass rolling process data;

[0013] The rolling process data of the target strip to be rolled in the previous pass are calculated according to the rolling process data of the target strip to be rolled in the next pass, and the rolling mill starts non-first pass rolling of the target strip to be rolled according to the rolling process data of the next pass.

[0014] The rolling process of the target strip to be rolled is divided into a non-steady-state accelerated rolling stage, a steady-state rolling stage, and a non-steady-state decelerated rolling stage. When the rolling process transitions from the non-steady-state accelerated rolling stage to the steady-state rolling stage, the strip coil diameter D at the mill outlet is recorded. 出 = d, as the steady-state rolling process proceeds, the strip coil diameter D at the mill exit 出 Gradually increases, the strip coil diameter D at the rolling mill entrance 入 Gradually decreases, when D 入 When it decreases to d, the rolling process transitions from the steady-state rolling stage to the non-steady-state deceleration rolling stage.

[0015] Obtain the first pass sub-steady-state data of all historical rolling processes and build a feature library of historical first pass sub-steady-state data, where the first pass sub-steady-state data includes: strip width B 历史首n , entrance thickness H 历史首n , outlet thickness h 历史首n , inlet tension T 历史首n , outlet tension t 历史首n , Steady rolling speed V 历史首n , Strip elongation δ 历史首n ;

[0016] n represents the rolling process number, which is a positive integer.

[0017] The characteristic of the target strip to be rolled is the entrance thickness H of the first pass strip. 目标首n ;

[0018] Retrieving the historical first-pass sub-steady-state data that meets the characteristics of the target strip to be rolled in the historical first-pass sub-steady-state data feature library means searching for H in the historical first-pass sub-steady-state data feature library. 历史首n , ensure H 历史首n is the closest to the target strip entrance thickness H to be rolled 目标首n The value of H 历史首n Corresponding strip width B 历史首n , outlet thickness h 历史首n , inlet tension T 历史首n , outlet tension t 历史首n , Steady rolling speed V 历史首n , Strip elongation δ 历史首n ;

[0019] Calculate the rolling process data for the first pass of the to-be-rolled target strip, including:

[0020] T 目标首n = T 历史首n B 目标首n H 目标首n / B 历史首n H 历史首n

[0021] t 目标首n = h 目标首n / H 目标首n T 目标首n

[0022] V 目标首n = V 历史首n h 历史首n / h 目标首n

[0023] a 目标首n = 0.5H 目标首n δ 目标首n / H 历史首n δ 历史首n

[0024] In the formula, B 目标首n is the strip width of the to-be-rolled target strip, H 目标首n is the mill inlet thickness of the to-be-rolled target strip in the first pass, h 目标首n is the mill outlet thickness of the to-be-rolled target strip in the first pass, δ 目标首n is the strip elongation of the to-be-rolled target strip, all of which are known values;

[0025] In the formula, T 目标首n represents the mill inlet tension of the to-be-rolled target strip in the first pass, t 目标首n represents the mill outlet tension of the to-be-rolled target strip in the first pass, V 目标首n represents the rolling speed of the to-be-rolled target strip in the first-pass steady rolling stage, a 目标首n represents the rolling acceleration of the to-be-rolled target strip in the first-pass non-steady acceleration stage. The rolling acceleration of the to-be-rolled target strip in the first-pass non-steady deceleration stage is -a 目标首n .

[0026] According to the rolling process data of the previous pass of the to-be-rolled target strip, calculate the rolling process data of the next pass of the to-be-rolled target strip, specifically including:

[0027] T 目标i = t 目标(i-1)

[0028] t 目标i = T 目标i h 目标i / H 目标i

[0029] V 目标i = V 目标(i-1) h 目标(i-1) / h 目标i

[0030] a 目标i = -a 目标(i-1) h 目标i / h 目标(i-1)

[0031] In the formula, i represents the pass number of the current rolling process, i = 2, 3, 4, 5...;

[0032] In the formula, h 目标i is the thickness of the target strip to be rolled at the exit of the rolling mill in the i-th pass, H 目标首n is the thickness of the target strip to be rolled at the entrance of the rolling mill in the i-th pass, h 目标(i-1) is the thickness of the target strip to be rolled at the exit of the rolling mill in the (i - 1)-th pass, all of which are known values;

[0033] In the formula, t 目标(i-1) represents the tension of the target strip to be rolled at the exit of the rolling mill in the (i - 1)-th pass, V 目标(i-1) represents the rolling speed of the target strip to be rolled in the steady rolling stage in the (i - 1)-th pass, -a 目标(i-1) represents the rolling acceleration of the target strip to be rolled in the non-steady deceleration stage in the (i - 1)-th pass;

[0034] In the formula, T 目标i represents the tension of the target strip to be rolled at the entrance of the rolling mill in the i-th pass, t 目标i represents the tension of the target strip to be rolled at the exit of the rolling mill in the i-th pass, V 目标i represents the rolling speed of the target strip to be rolled in the steady rolling stage in the i-th pass, a 目标i represents the rolling acceleration of the target strip to be rolled in the non-steady acceleration stage in the i-th pass, and the rolling acceleration of the target strip to be rolled in the non-steady deceleration stage in the i-th pass is -a 目标i .

[0035] A laser emitter is installed above the edge of the target strip to be rolled;

[0036] A laser receiver is installed below the edge of the target strip to be rolled;

[0037] If the laser emitted by the laser emitter is detected by the laser receiver, it is determined that there is a risk of strip breakage, and the laser receiver sends a pre-warning signal before strip breakage to the rolling mill control system, and the rolling mill control system controls the rolling mill to stop.

[0038] During the rolling process, an edge and thickness measurement system located above the strip to be rolled reciprocates and moves cyclically along the width direction of the strip to detect the thickness of the strip edges and the middle part. The edge and thickness measurement system sends the strip thickness data to the rolling mill screwdown system. After receiving the strip thickness data, the rolling mill screwdown system controls the action of the screwdown cylinder so that the thickness of the middle part of the strip to be rolled is 1.01 times the thickness of the strip edges.

[0039] The beneficial effects of the present invention are as follows:

[0040] (1) A historical first-pass steady-state data feature library is established in advance. According to the specifications of the strip to be rolled, the specification data that meet the requirements are retrieved from the historical first-pass steady-state data feature library. Then, the first-pass rolling process data of the strip to be rolled are calculated. Moreover, the rolling process data of the previous pass are used as the given basis for the rolling process data of the next pass, greatly reducing the length of the out-of-tolerance sections at the head and tail of the strip.

[0041] (2) An edge and thickness measurement system that reciprocates along the width direction of the strip to be rolled is provided above the strip to be rolled. The edge and thickness measurement system detects the thickness fluctuation of the strip and sends it to the rolling mill screwdown system, forming a closed-loop control between the two to ensure that the thickness of the strip edges is always less than the thickness of the middle part. Therefore, it is ensured that the middle part of the strip can withstand a greater tensile stress, guaranteeing the stable rolling of the ultra-thin strip of special alloy.

[0042] (3) A laser emitter and a laser receiver are arranged above and below the strip to be rolled. Whether the laser spot emitted by the laser emitter is detected by the laser receiver is used as the signaling condition for strip break warning. If a signal is sent, an emergency stop is carried out. That is, through the precise detection of cracks in the strip edges, the possibility of strip break is greatly reduced.

[0043] To make the above content of the present invention more obvious and understandable, the following specific preferred embodiments are given and described in detail in conjunction with the accompanying drawings. Description of the Drawings

[0044] Figure 1 It is a schematic diagram of the stable rolling process of the ultra-thin strip of special alloy. Detailed Embodiments

[0045] The following specific embodiments illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0046] It should be noted that in the present invention, the up, down, left, and right in the drawings are regarded as the up, down, left, and right in the stable rolling process of the ultra-thin strip of special alloy described in this specification.

[0047] Reference is now made to the accompanying drawings to describe exemplary embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely, and to fully convey the scope of the present invention to those skilled in the art. The terms in the exemplary embodiments shown in the drawings are not intended to limit the present invention. In the drawings, the same units / components are denoted by the same reference numerals.

[0048] Unless otherwise specified, the terms used herein (including scientific and technical terms) have the ordinary meaning understood by those skilled in the art. In addition, it can be understood that the terms defined in the commonly used dictionary should be understood to have a meaning consistent with the context of their related fields, and should not be understood as idealized or overly formal meanings.

[0049] This embodiment relates to a stable rolling process for ultra-thin strips of special alloys. Special alloys are iron-carbon alloys formed by adding an appropriate amount of one or more alloying elements on the basis of ordinary carbon steel; ultra-thin strips refer to metal strips with a thickness of less than 0.02 - 0.03 mm, and generally those with a thickness of less than 0.05 mm are called ultra-thin strips.

[0050] Before starting the rolling process provided in this embodiment, when producing ultra-thin strips using conventional processes, more reliance is placed on the experience and operating level of the operators. When changing products or operators, it is necessary to re-explore the process, which is time-consuming and material-consuming. After adopting the rolling process provided in this embodiment, the process data in this embodiment can be collected, supplemented into the database, and the database can be updated to ensure the accuracy of the process data in the database.

[0051] It should be noted that hereinafter, the strip to be rolled will be referred to as the target strip to be rolled.

[0052] According to the characteristics of rolling production, the rolling process of the target strip to be rolled in this embodiment is divided into three stages, namely the non-steady-state acceleration rolling stage, the steady-state rolling stage, and the non-steady-state deceleration rolling stage. In the same pass, the set values of the tension in these three stages do not change, but the speeds and accelerations in the three stages are different. Therefore, the rolling process data calculated hereinafter mainly refers to the speed and acceleration.

[0053] The stable rolling process for ultra-thin strips of special alloys, refer to Figure 1 , includes the following steps:

[0054] 100. Obtain the steady-state data of the first pass of all historical rolling processes and construct a historical first-pass steady-state data feature library.

[0055] The steady-state data of the first pass includes: strip width B 历史首n , inlet thickness H 历史首n , outlet thickness h历史首n , the inlet tension T 历史首n , the outlet tension t 历史首n , the steady-state rolling speed V 历史首n , the strip elongation δ 历史首n , where n represents the rolling pass number, which is a positive integer, and n takes 1, 2, 3, 4...

[0056] 200. According to the characteristics of the to-be-rolled target strip, retrieve the historical first-pass steady-state data that conforms to the characteristics of the to-be-rolled target strip from the historical first-pass steady-state data feature library, calculate the first-pass rolling process data of the to-be-rolled target strip, start the rolling mill, and the rolling mill rolls the to-be-rolled target strip according to the first-pass rolling process data.

[0057] 201. The characteristics (or specifications) of the to-be-rolled target strip are the first-pass inlet thickness H 目标首n .

[0058] 202. Retrieving the historical first-pass steady-state data that conforms to the characteristics of the to-be-rolled target strip from the historical first-pass steady-state data feature library means searching for H 历史首n in the historical first-pass steady-state data feature library to ensure that H 历史首n is the value closest to the inlet thickness H 目标首n of the to-be-rolled target strip. For example, if the H 目标首n of the to-be-rolled target strip is 0.049 mm, and the values of H 历史首n in the data feature library are 0.051 mm, 0.050 mm, 0.048 mm, 0.047 mm..., then 0.048 mm of H 历史首n can be selected as the value closest to H 目标首n .

[0059] The reason for choosing 0.048 mm of H 历史首n as the value closest to H 目标首n instead of 0.050 mm is that the thinner the strip thickness, the more difficult it is to roll, so the reference significance of thin strips is greater.

[0060] 203. After confirming the closest value, retrieve the strip width B 历史首n corresponding to H 历史首n , the outlet thickness h 历史首n , the inlet tension T 历史首n , the outlet tension t 历史首n , the steady-state rolling speed V 历史首n , the strip elongation δ 历史首n from the data feature library, and calculate (weighted assignment) the first-pass rolling process data of the to-be-rolled target strip based on the above values, including:

[0061] T 目标首n = T 历史首n B 目标首n H目标首n / B 历史首n H 历史首n

[0062] t 目标首n =h 目标首n / H 目标首n T 目标首n

[0063] V 目标首n =V 历史首n h 历史首n / h 目标首n

[0064] a 目标首n =0.5H 目标首n δ 目标首n / H 历史首n δ 历史首n

[0065] In the formula, B 目标首n is the strip width of the strip to be rolled, H 目标首n is the mill inlet thickness of the strip to be rolled in the first pass, h 目标首n is the mill outlet thickness of the strip to be rolled in the first pass, δ 目标首n is the strip elongation of the strip to be rolled, and all are known values;

[0066] In the formula, T 目标首n represents the mill inlet tension of the strip to be rolled in the first pass, t 目标首n represents the mill outlet tension of the strip to be rolled in the first pass, V 目标首n represents the rolling speed of the strip to be rolled in the steady rolling stage of the first pass, a 目标首n represents the rolling acceleration of the strip to be rolled in the non-steady acceleration stage of the first pass. The rolling acceleration of the strip to be rolled in the non-steady deceleration stage of the first pass is -a 目标首n .

[0067] In the first pass, regardless of which stage the rolling process is in, the mill inlet tension T 目标首n is constant. Similarly, the mill outlet tension t 目标首n is also constant.

[0068] 204. Calculate the rolling process data of the strip to be rolled in the next pass according to the rolling process data of the strip to be rolled in the previous pass, and the mill starts the non-first-pass rolling of the strip to be rolled according to the rolling process data of the next pass.

[0069] Specifically, it includes:

[0070] T 目标i =t 目标(i-1)

[0071] t目标i = T 目标i h 目标i / H 目标i

[0072] V 目标i = V 目标(i-1) h 目标(i-1) / h 目标i

[0073] a 目标i = -a 目标(i-1) h 目标i / h 目标(i-1)

[0074] In the formula, i represents the pass number of the current rolling process, i = 2, 3, 4, 5...;

[0075] In the formula, h 目标i is the thickness of the strip to be rolled at the exit of the rolling mill in the i-th pass, H 目标首n is the thickness of the strip to be rolled at the entrance of the rolling mill in the i-th pass, h 目标(i-1) is the thickness of the strip to be rolled at the exit of the rolling mill in the (i - 1)-th pass, and all are known values;

[0076] In the formula, t 目标(i-1) represents the tension at the exit of the rolling mill for the strip to be rolled in the (i - 1)-th pass, V 目标(i-1) represents the rolling speed of the strip to be rolled in the steady rolling stage of the (i - 1)-th pass, -a 目标(i-1) represents the rolling acceleration of the strip to be rolled in the non-steady deceleration stage of the (i - 1)-th pass;

[0077] In the formula, T 目标i represents the tension at the entrance of the rolling mill for the strip to be rolled in the i-th pass, t 目标i represents the tension at the exit of the rolling mill for the strip to be rolled in the i-th pass, V 目标i represents the rolling speed of the strip to be rolled in the steady rolling stage of the i-th pass, a 目标i represents the rolling acceleration of the strip to be rolled in the non-steady acceleration stage of the i-th pass, and the rolling acceleration of the strip to be rolled in the non-steady deceleration stage of the i-th pass is -a 目标i .

[0078] It can be seen from the above formula that the process data on the exit side of the previous pass (tension t 目标(i-1) at the exit of the rolling mill, thickness h 目标(i-1) at the exit of the rolling mill, acceleration -a 目标(i-1) ) are used as the process data on the entrance side of the next pass (tension T 目标i at the entrance of the rolling mill, tension t 目标i at the exit of the rolling mill, acceleration a 目标i) The setting basis, or rather, taking the process data on the outlet side of this pass as the given standard for the process data on the inlet side of the next pass, aims to reduce the length of the over-tolerance sections at the head and tail.

[0079] The acceleration in the non-steady-state acceleration rolling stage and the acceleration in the non-steady-state deceleration rolling stage are opposite to each other. Specifically, in the non-steady-state acceleration rolling stage, the rolling speed accelerates from 0 with an acceleration of a 目标i and when it reaches the target speed V 目标i , it transitions to the steady-state rolling stage, and the strip coil diameter D at the outlet side of the rolling mill at this moment is recorded 出 = d; as the steady-state rolling process progresses, D 出 gradually increases, D 入 gradually decreases, and when D 入 decreases to d, the rolling process transitions from the steady-state rolling stage to the non-steady-state deceleration rolling stage and decelerates to a stop with -a 目标i . That is to say, the strip length passed by accelerating from 0 with an acceleration of a 目标i to V 目标i and the strip length passed by decelerating from V 目标i with a deceleration of -a 目标i to 0 are the same, so the resulting coil diameter changes are also the same, and it is on the premise that the strip diameter at the inlet reel at the time of stopping is the same as the strip diameter at the outlet reel at the time of starting.

[0080] Refer to Figure 1 , generally speaking, it is necessary to first establish a historical first-pass steady-state data feature library, and then calculate the first-pass rolling process data of the strip to be rolled according to the historical first-pass steady-state data feature library, that is, "whether it is the first pass, yes", and then calculate the non-first-pass rolling process data of the strip to be rolled, that is, "whether it is the first pass, no, i = 2". At this time, the rolling speed in the steady-state rolling stage and the rolling acceleration in the non-steady-state rolling stage have been obtained, and the rolling in the non-steady-state acceleration stage starts. In the non-steady-state acceleration rolling stage, the rolling speed accelerates from 0 with an acceleration of a i and when it reaches the target speed V 目标i , it transitions to the steady-state rolling stage, and the strip coil diameter D at the outlet side of the rolling mill at this moment is recorded 出 = d; as the steady-state rolling process progresses, D 出 gradually increases, D 入 gradually decreases, and when D 入 decreases to d, that is Figure 1 the "yes" in i , then the rolling process transitions from the steady-state rolling stage to the non-steady-state deceleration rolling stage and decelerates to a stop with -a 入 , and this pass of rolling is completed. If the value of D Figure 1 is not d, that is

[0081] During the rolling process of the strip, the width direction is the free end with the least resistance. Therefore, edge cracks are extremely likely to occur after repeated rolling, which in turn causes the tensile stress of the strip to suddenly rise and leads to strip breakage.

[0082] To prevent the occurrence of serious accidents such as strip breakage, a laser emitter is installed above the edge of the strip to be rolled, and a laser receiver is installed below the edge of the strip to be rolled. The laser emitter and the laser receiver are arranged vertically opposite each other, and the strip to be rolled passes through between the two.

[0083] The detection range of the laser emitter and the laser receiver is the distance between the drive side of the strip and the center line of the unit. This distance is 0.475 - 0.5 times the strip width because the strip in this area is prone to edge cracks due to the transverse flow of metal.

[0084] If the laser emitted by the laser emitter is detected by the laser receiver, it is determined that there is a risk of strip breakage. The laser receiver sends a pre-warning signal before strip breakage to the rolling mill control system, and the rolling mill control system controls the rolling mill to stop, as follows:

[0085] When the strip has an edge crack, the laser emitted by the laser emitter can pass through the crack area and be received by the laser receiver. Therefore, when the laser receiver detects the laser, it is determined as a pre-warning signal before strip breakage and immediately sends a signal. At this time, the unit speed will stop urgently, and the corresponding acceleration is -1.5 m / s 2 .

[0086] To reduce the control difficulty of the shape control system and improve the thickness difference accuracy of the final product, this embodiment also installs a side-edge thickness measurement system above the strip to be rolled. Specifically, during the rolling process, the side-edge thickness measurement system located above the strip to be rolled reciprocates and circulates along the width direction of the strip to detect the thickness of the strip edge and the middle thickness. The side-edge thickness measurement system sends the strip thickness data to the rolling mill roll gap control system. After receiving the strip thickness data, the rolling mill roll gap control system controls the action of the hydraulic cylinder to make the middle thickness of the strip to be rolled 1.01 times the thickness of the strip edge, that is, the side-edge thickness measurement system and the hydraulic cylinder form a closed-loop control.

[0087] The rolling mill roll gap control system is a conventional device of the rolling mill. The main actuator is the hydraulic cylinder that controls the roll gap of the rolling mill. The thickness of the strip is basically the same as the roll gap.

[0088] The side-edge thickness measurement system and the hydraulic cylinder form a closed-loop control, which means that when the side-edge thickness measurement system detects fluctuations in the strip thickness, the thickness of the strip is changed by raising or lowering the hydraulic cylinder. By controlling the amount of extension or retraction of the hydraulic cylinder, the cross-sectional convexity of the strip can be changed.

[0089] The edge - tracing thickness - measuring system is a thickness - measuring instrument that can move linearly. The moving range is between the drive side of the strip and the center line of the unit. The width of this range is 0 - 0.5 times the strip width. In addition, the moving frequency F of the edge - tracing thickness - measuring system has the following positive - correlation relationship with the strip linear velocity V and the strip thickness h:

[0090] F = V / h

[0091] As for the linear - moving mode of the thickness - measuring instrument, it can be an electric - push - rod type, oil - cylinder telescoping, etc., without limitation.

[0092] The closed - loop control of the edge - tracing thickness - measuring system and the rolling - mill screwdown system can ensure that the thickness of the middle part of the strip is about 1.01 times that of its edge part. Therefore, the middle part of the strip can withstand a greater tensile stress, and the edge part of the strip will be trimmed to a fixed length in the subsequent finishing process. Thus, this thickness difference will not affect the thickness - difference accuracy of the product.

[0093] In summary, the stable rolling process of the ultra - thin special - alloy strip specifically includes the following steps:

[0094] Obtain the first - pass steady - state data of all historical rolling processes and construct a historical first - pass steady - state data feature library;

[0095] According to the characteristics of the strip to be rolled, automatically retrieve the historical first - pass steady - state data of the strip with similar or identical characteristics to those of the strip to be rolled in the historical first - pass steady - state data feature library, calculate and issue the first - pass rolling process data of the strip to be rolled, start the rolling mill, and the rolling mill rolls the strip to be rolled according to the first - pass rolling process data;

[0096] Accelerate non - steadily and transition to steady - state rolling, and record the coiling diameter D of the strip at the exit side at this time 出 = d;

[0097] Steady - state rolling;

[0098] The edge - tracing thickness - measuring system and the rolling - mill screwdown system jointly form a closed - loop control for the plate thickness of the strip to be rolled and make the center thickness always 1.01 times that of the edge thickness;

[0099] The laser emitter continuously emits laser light, and when the laser receiver detects the laser light, it immediately sends a signal;

[0100] If the laser receiver sends a signal, the rolling mill automatically stops and ends the rolling of this pass;

[0101] If the laser receiver never sends a signal, continue steady - state rolling and when the coiling diameter D of the strip on the entry side 入 equals d, the system enters the non - steady - state deceleration stage and stops until it stops;

[0102] Start the rolling of the next pass;

[0103] Based on the rolling process data of the previous pass of the to-be-rolled target strip, calculate the rolling process data of the next pass of the to-be-rolled target strip, and the rolling mill starts the non-first-pass rolling of the to-be-rolled target strip according to the rolling process data of the next pass until the finished product specification is reached.

[0104] The present invention automatically retrieves the first-pass empirical data of the rolled rolling process according to the specifications of the to-be-rolled raw material, calculates, issues, and completes the rolling of the first-pass non-steady-state acceleration stage of this rolling process, and uses the relevant data of the non-steady-state acceleration stage as the process data setting standard for the non-steady-state deceleration stage. Moreover, the present invention uses the process data on the exit side of this pass as the given standard for the process data on the entrance side of the next pass, greatly reducing the length of the head and tail out-of-tolerance sections.

[0105] The edge detection and thickness measurement system provided by the present invention and the rolling mill screwdown system form a closed-loop control, making the edge thickness of the strip in the steady-state rolling stage and the non-steady-state rolling stage less than its middle thickness. Moreover, whether the laser spot emitted by the laser emitter is detected by the laser receiver is used as the signaling condition for strip break warning, and in case of signaling, an emergency stop is carried out. The present invention greatly reduces the possibility of strip breakage and reduces the length of the head and tail out-of-tolerance sections, which not only reduces the waste of expensive special alloy raw materials but also realizes the stable rolling of extremely thin strips. Those of ordinary skill in the art can understand that the above embodiments are specific embodiments for implementing the present invention, and in practical applications, various changes can be made in form and details without departing from the spirit and scope of the present invention.

Claims

1. A stable rolling process for extremely thin strips of special alloys, characterized in that, It includes the following steps: Obtain the first-pass steady-state data of all historical rolling processes and construct a historical first-pass steady-state data feature library; According to the characteristics of the to-be-rolled target strip, retrieve the historical first-pass steady-state data that conforms to the characteristics of the to-be-rolled target strip in the historical first-pass steady-state data feature library, calculate the first-pass rolling process data of the to-be-rolled target strip, start the rolling mill, and the rolling mill rolls the to-be-rolled target strip according to the first-pass rolling process data; Among them, the characteristics of the strip to be rolled are the inlet thickness H of the strip in the first pass 目标首n ; Retrieving historical first-pass steady-state data that matches the characteristics of the to-be-rolled target strip in the historical first-pass steady-state data feature library means searching for the entry thickness H in the historical first-pass steady-state data feature library 历史首n , ensuring that H 历史首n is the value closest to the entry thickness H 目标首n of the to-be-rolled target strip, and retrieving the strip width B 历史首n corresponding to the H 历史首n , the exit thickness h 历史首n , the entry tension T 历史首n , the exit tension t 历史首n , the steady-state rolling speed V 历史首n , the strip elongation δ 历史首n ; Calculating the first-pass rolling process data of the to-be-rolled target strip includes: In the formula, B 目标首n is the strip width of the strip to be rolled, H 目标首n is the mill entry thickness of the strip to be rolled in the first pass, h 目标首n is the mill exit thickness of the strip to be rolled in the first pass, δ 目标首n is the strip elongation of the strip to be rolled, all of which are known values; Where, T 目标首n represents the inlet tension of the first pass rolling mill for the strip to be rolled, t 目标首n represents the outlet tension of the first pass rolling mill for the strip to be rolled, V 目标首n represents the rolling speed of the strip to be rolled in the steady-state rolling stage of the first pass, a 目标首n represents the rolling acceleration of the strip to be rolled in the non-steady-state acceleration rolling stage of the first pass, and the rolling acceleration of the strip to be rolled in the non-steady-state deceleration rolling stage of the first pass is -a 目标首n ; According to the rolling process data of the previous pass of the to-be-rolled target strip, calculate the rolling process data of the next pass of the to-be-rolled target strip, and the rolling mill starts the non-first-pass rolling of the to-be-rolled target strip according to the rolling process data of the next pass; Among them, calculating the rolling process data of the next pass of the to-be-rolled target strip according to the rolling process data of the previous pass of the to-be-rolled target strip specifically includes: T 目标i = t 目标(i-1) In the formula, i represents the pass number of the current rolling process, i = 2, 3, 4, 5...; where h 目标i is the thickness of the strip to be rolled at the mill exit in the i-th pass, H 目标首n is the thickness of the strip to be rolled at the mill entrance in the i-th pass, h 目标(i-1) is the thickness of the strip to be rolled at the mill exit in the (i - 1)-th pass, and all are known values; where t 目标(i-1) represents the mill exit tension of the strip to be rolled in the (i - 1)-th pass, V 目标(i-1) represents the rolling speed of the strip to be rolled in the steady rolling stage of the (i - 1)-th pass, -a 目标(i-1) represents the rolling acceleration of the strip to be rolled in the non-steady deceleration rolling stage of the (i - 1)-th pass; Wherein, T 目标i represents the mill inlet tension of the strip to be rolled at the i-th pass, t 目标i represents the mill outlet tension of the strip to be rolled at the i-th pass, V 目标i represents the rolling speed of the strip to be rolled in the steady rolling stage at the i-th pass, a 目标i represents the rolling acceleration of the strip to be rolled in the unsteady acceleration rolling stage at the i-th pass. The rolling acceleration of the strip to be rolled in the unsteady deceleration rolling stage at the i-th pass is -a 目标i ; The rolling process of the to-be-rolled target strip is divided into an unsteady acceleration rolling stage, a steady-state rolling stage, and an unsteady deceleration rolling stage. When the rolling process transitions from the unsteady acceleration rolling stage to the steady-state rolling stage, the strip coil diameter D on the exit side of the rolling mill is recorded. 出 = d. As the steady-state rolling process progresses, the strip coil diameter D on the exit side of the rolling mill 出 gradually increases, and the strip coil diameter D on the entrance side of the rolling mill 入 gradually decreases. When D 入 decreases to d, the rolling process transitions from the steady-state rolling stage to the unsteady deceleration rolling stage. Obtain the first-pass steady-state data of all historical rolling processes and construct a feature library of historical first-pass steady-state data, where the first-pass steady-state data includes: strip width B 历史首n , inlet thickness H 历史首n , outlet thickness h 历史首n , inlet tension T 历史首n , outlet tension t 历史首n , steady-state rolling speed V 历史首n , strip elongation δ 历史首n ; n represents the rolling process number, which is a positive integer.

2. The stable rolling process of the special alloy ultra-thin strip according to claim 1, characterized in that A laser emitter is installed above the edge of the to-be-rolled target strip; A laser receiver is installed below the edge of the to-be-rolled target strip; If the laser emitted by the laser emitter is detected by the laser receiver, it is determined that there is a risk of strip breakage. The laser receiver sends a pre-warning signal before strip breakage to the rolling mill control system, and the rolling mill control system controls the rolling mill to stop.

3. The stable rolling process of the special alloy ultra-thin strip according to claim 1 or 2, characterized in that, During the rolling process, the edge and thickness inspection system located above the to-be-rolled target strip reciprocally moves cyclically along the width direction of the strip to detect the edge thickness and the middle thickness of the strip. The edge and thickness inspection system sends the strip thickness data to the rolling mill screwdown system. After receiving the strip thickness data, the rolling mill screwdown system controls the action of the screwdown cylinder so that the middle thickness of the to-be-rolled target strip is 1.01 times the edge thickness of the strip.

Images