A method and control system for straightening stainless steel sheet

Abstract

The application discloses a kind of stainless steel sheet straightening method and control system, including following several steps S1: slab is heated, solid solution heat treatment is carried out to the slab after heating S2: to the plate after rolling S3: the plate after quenching S4: the plate after shot blasting treatment is made into straightening machine and is straightened with the length direction of roller way length direction Angle entering straightening treatment S5: the plate after straightening is pickled, and is ground, by the plate material number input control system, corresponding size data is generated by identifying material number, and corresponding control information is generated according to the size data, and control information is sent to control module, and the angle of the length direction of the plate and the length direction of roller way is adjusted according to control information by control module to center device, it is simple to operate, and the adjustment precision is high.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of stainless steel plate processing, in particular to a straightening method and control system for stainless steel sheet. BACKGROUND

[0002] The stainless steel plate processing flow is to perform slab heating, rolling, solid solution heat treatment, straightening, shot blasting, pickling, grinding and packaging and other processes. The solid solution heat treatment, straightening, shot blasting and other processes determine the unevenness of the ordinary austenitic stainless steel plate. The flatness of the stainless steel is usually specified in the factory standard or technical agreement. For example, the austenitic stainless steel plate with a thin specification thickness of ≤10 mm is generally required to have a flatness of ≤5 mm / m at delivery. However, after solid solution heat treatment and quenching, the flatness of the austenitic stainless steel plate with a thin specification thickness of ≤10 mm is 10-30 mm / m. After straightening, the flatness of some steel plates is about 6-10 mm / m. However, after pickling, the stress is released again, and the flatness rebounds to a certain extent, which cannot meet the standard and user requirements, resulting in multiple and re-straightening problems, and low straightening qualification rate.

[0003] Currently, there are mainly two kinds of process methods for straightening process quality related pressure processing:

[0004] The first kind is to sequentially perform slab heating, rolling, solid solution heat treatment, straightening, shot blasting, pickling, grinding, packaging and other processes on the austenitic stainless steel plate with a thickness of ≤10 mm. The solid solution heat treatment and straightening process adopt a roller bottom type heat treatment furnace and a roller bottom type quenching machine. The solid solution heat treatment, straightening process and shot blasting process determine the unevenness of the austenitic stainless steel plate with a specification thickness of ≤10 mm and the quality of the upper and lower surfaces. After solid solution heat treatment and quenching, the flatness of some steel plates is 10-15 mm / m. The main defects are C-shaped bending of the head (tail) of the steel plate, head and tail warping of the steel plate, and head and tail denting of the steel plate. These defects occur in the range of 0-300 mm of the head and tail of the steel plate. At the same time, this method usually adopts a four-fold 9-roller straightening machine. The number of straightening rollers of this straightening machine is 5 upper rollers and 6 lower rollers, and it also includes guide rollers. The steel plate advances in the forward direction on the track. When the steel plate enters the straightening machine, the long axis of the steel plate is perpendicular to the length direction of the straightening rollers. The principle of the multi-roller type steel plate straightening machine leads to the fact that the above-mentioned defects are difficult to straighten at one time and need to be straightened multiple times. In addition, this process is to straighten first and then shot blast. Due to multiple straightening, defects such as pitted surface, pitted point and scratch are caused on the surface of the steel plate during the actual straightening process. These defects are exposed in the subsequent pickling process, which increases the workload of the grinding process and also increases the re-pickling rate of the steel plate.

[0005] The second method involves sequentially heating, rolling, solution heat treatment, straightening, shot blasting, pickling, grinding, and packaging austenitic stainless steel plates with a thickness ≤10mm. The solution heat treatment process, online water cooling for quenching, straightening, and shot blasting determine the flatness and surface quality of the thin-gauge austenitic stainless steel plates with a thickness ≤10mm. After solution heat treatment and quenching, some plates have a flatness of 10-50mm / m. The main defects are C-shaped bending at the head (tail), curling at the head and tail, and tapping at the head and tail, similar to the first processing method. The principle of existing multi-roller steel plate straightening machines makes it difficult to straighten these defects in one pass. Furthermore, this process involves straightening before shot blasting, resulting in multiple straightening operations that cause surface defects such as pitting, scratches, and roughness. These defects are exposed during the subsequent pickling process, increasing the workload of the grinding process and raising the re-acidification rate of the steel plate.

[0006] Therefore, a straightening method is needed for thin austenitic stainless steel plates with a thickness of ≤10mm to effectively improve the first-pass yield of the straightening process. Summary of the Invention

[0007] To solve the above-mentioned technical problems, the present invention provides a method for straightening stainless steel sheet, comprising:

[0008] S1: Heat the slab and then roll the heated slab.

[0009] S2: The rolled sheet is subjected to solution heat treatment and then quenched in water;

[0010] S3: The plate material after water quenching is shot blasted;

[0011] S4: The length direction of the shot-blasted plate is at a certain angle to the length direction of the roller conveyor before entering the straightening machine for straightening.

[0012] S5: After straightening, the plate is pickled and ground.

[0013] Preferably, in step S2, the quenching treatment specifically adopts a combination of spraying and water tank cooling.

[0014] Preferred: The temperature of the plate after quenching is ≤150℃, and the flatness of the steel plate is ≤30mm / m.

[0015] Preferably, in step S3, high-carbon steel shot is used in the shot blasting process, specifically S280 shot, and the surface finish of the plate after shot blasting is ASa2.5.

[0016] Preferably, in the S4, a centering device is installed on the straightening machine transmission roller table, which is used to adjust the angle of the plate, so that the length direction of the plate is at a certain angle with the length direction of the roller table.

[0017] Preferably, when the thickness h of the plate is 5≤h≤7mm, the angle is 26-30°.

[0018] Preferably, when the thickness h of the plate is 7

[0019] Preferably, when the thickness h of the plate is 8

[0020] A control system is provided, comprising:

[0021] An input module is used to input the material number of the stainless steel sheet, generate corresponding size data after inputting the material number, and generate a control information according to the size data and transmit it to the corresponding module;

[0022] A control module is used to control the corresponding station according to the control information.

[0023] Preferably, after the plate material number is input into the input module, the corresponding size data is generated by identifying the material number, the corresponding control information is generated according to the size data, and the control information is transmitted to the control module, and the control module controls the centering device to adjust the angle between the length direction of the plate and the length direction of the roller table.

[0024] The technical effects and advantages of the present application are as follows:

[0025] 1. A new processing technology is adopted, that is, the plate is subjected to solution treatment and then is subjected to shot blasting treatment, and then is subjected to straightening, so that the length direction of the plate after shot blasting treatment is at a certain angle with the length direction of the roller table and enters the straightening machine for straightening treatment, which greatly improves the first pass rate in the straightening process and effectively improves the surface quality problems (pitting, scratches) of the plate.

[0026] 2. By inputting the plate material number into the control system, the corresponding size data is generated by identifying the material number, the corresponding control information is generated according to the size data, and the control information is transmitted to the control module, and the control module controls the centering device to adjust the angle between the length direction of the plate and the length direction of the roller table, which is simple in operation and high in adjustment precision. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a schematic diagram of a straightening method of a stainless steel sheet provided by the embodiment of the present application;

[0028] Figure 2This is a schematic diagram of a control system provided in an embodiment of this application;

[0029] Figure 3 This is a schematic diagram of a processing method for hot-rolled 316L austenitic stainless steel plate provided in an embodiment of this application;

[0030] Figure 4 This is a schematic diagram of a hot-rolled 304 austenitic stainless steel plate processing method provided in an embodiment of this application.

[0031] In the picture:

[0032] 10. Input module; 11. Control module. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and design various embodiments with various modifications suitable for a particular purpose.

[0034] Example 1

[0035] Depend on Figures 1-2 As shown, this embodiment provides a method for straightening a stainless steel sheet, including:

[0036] S1: Heat the slab and then roll the heated slab.

[0037] S2: The rolled sheet is subjected to solution heat treatment and then quenched in water;

[0038] S3: The plate material after water quenching is shot blasted;

[0039] S4: The length direction of the shot-blasted plate is at a certain angle to the length direction of the roller conveyor before entering the straightening machine for straightening.

[0040] S5: After straightening, the plate is pickled and ground.

[0041] The quenching process after the solution heat treatment in step S2 adopts the way of spraying and water tank cooling, the temperature of the quenched plate is controlled by the time of the plate passing through the spraying area and in the water tank, and the unevenness of the quenched plate is controlled, after quenching, the temperature of the plate is ≤150℃, and the unevenness is ≤30mm / m, which provides guarantee for the smooth passing of the plate through the shot blasting process, and the shot blasting process in step S3 specifically uses high-carbon steel shot, and the shot type is S280, and the plate smoothness after shot blasting is ASa2.5.

[0042] The centering device is installed on the straightening machine transmission roller way in step S4, and is used to adjust the angle of the plate, so that the length direction of the plate is at a certain angle with the length direction of the roller way, and the angle is related to the thickness of the plate:

[0043] When the thickness h of the plate is 5≤h≤7mm, the angle is 26-30°;

[0044] When the thickness h of the plate is 7<h≤8mm, the angle is 21-25°;

[0045] When the thickness h of the plate is 8<h≤10mm, the angle is 15-20°.

[0046] It should be noted that the traditional straightening principle is to make the length direction of the plate perpendicular to the length direction of the straightening roller to enter the straightening machine, and the plate is straightened by rotating the plurality of straightening rollers, and since the head, tail, head or tail of the plate has a certain arc, the contact point (line) between the straightening roller and the plate has a certain length, so when the straightening roller straightens the head, tail, head or tail of the plate, the straightening effect is poor, and the plate is inclined into the straightening machine by the centering device in the embodiment for straightening treatment, so that the arc surface of the head, tail, head or tail of the plate is staggered with the contact point (line) of the straightening roller, the straightening effect is good, the first pass rate in the straightening process is greatly improved, and the surface quality problem (pitting, scratch) of the plate is effectively improved.

[0047] A control system is also provided, comprising:

[0048] The input module 10 is used to input the material number of the stainless steel sheet, generate corresponding size data after inputting the material number, and generate a control information according to the size data and transmit the control information to the corresponding module;

[0049] The control module 11 controls the corresponding station according to the control information.

[0050] By inputting the material number of the sheet material into the control system, the input module 10 identifies the material number and generates corresponding size data, and generates corresponding control information based on the size data. The control information is then transmitted to the control module 11. The control module 11 controls the centering device to adjust the angle between the length direction of the sheet material and the length direction of the roller conveyor according to the control information. The operation is simple and the adjustment accuracy is high.

[0051] Example 2

[0052] Depend on Figure 3 As shown in this embodiment, a specific implementation method for a hot-rolled 316L austenitic stainless steel plate is provided. The plate has dimensions of 10mm thickness, 2600mm width, and 8500mm length. The plate material number is input into the control system. The plate undergoes solution heat treatment. After quenching following solution heat treatment, the plate temperature is 138℃, and the plate unevenness is 28mm / m. After quenching, shot blasting is performed using high-carbon steel shot, type S280. After shot blasting, the plate surface finish is ASa2.5. After shot blasting, the plate is conveyed to the straightening machine via a roller conveyor. The control system adjusts the plate position according to the plate size data using a centering device, making the plate length direction form a 15-20° angle with the overall roller conveyor length direction for straightening. After straightening, subsequent pickling and inspection (grinding) are performed. Using the above processing method, the first-pass yield of the straightening process is increased by 18%.

[0053] Example 3

[0054] Depend on Figure 4 As shown in this embodiment, a specific implementation method for a hot-rolled 304 austenitic stainless steel plate is provided. The plate has dimensions of 7.9 mm thickness, 2370 mm width, and 12010 mm length. The plate material number is input into the control system. The plate undergoes solution heat treatment. After quenching following solution heat treatment, the plate temperature is 126℃, and the plate unevenness is 20 mm / m. After quenching, shot blasting is performed using high-carbon steel shot, type S280. After shot blasting, the plate surface finish is ASa2.5. After shot blasting, the plate is conveyed to the straightening machine via a roller conveyor. The control system adjusts the plate position according to the plate size data using a centering device, making the plate length direction form an angle of 21-25° with the overall roller conveyor length direction for straightening. After straightening, subsequent pickling and inspection (grinding) are performed. Using the above processing method, the first-pass yield of the straightening process is increased by 16%.

[0055] The working principle of this invention is:

[0056] The method comprises the following steps: S1, heating the slab, rolling the heated slab, S2, solid solution heat treatment and quenching the rolled slab, S3, shot blasting the quenched slab, S4, the length direction of the shot blasted slab is at a certain angle with the length direction of the roller way, and the shot blasted slab enters the straightening machine for straightening treatment, S5, pickling and dressing the straightened slab, wherein the quenching process after the solid solution heat treatment in step S2 adopts the way of spraying and water tank cooling, the temperature of the quenched slab is controlled by the time of the slab passing through the spraying area and in the water tank, and the unevenness of the quenched slab is controlled, after quenching, the temperature of the slab is less than or equal to 150 DEG C, and the unevenness is less than or equal to 30 mm / m, which provides guarantee for the smooth passing of the slab through the shot blasting process, and the shot blasting process in step S3 specifically uses high-carbon steel shot, the shot model is S280, and the smoothness of the shot blasted slab is ASa2.5, the centering device is installed on the transmission roller way of the straightening machine in step S4, the centering device is used to adjust the angle of the slab, so that the length direction of the slab is at a certain angle with the length direction of the roller way, the angle is related to the thickness of the slab, and the method further comprises a control system, the material number of the slab is input into the control system, the input module 10 identifies the material number and generates corresponding size data, the control information is generated according to the size data, the control information is transmitted to the control module 11, and the control module 11 controls the centering device to adjust the angle between the length direction of the slab and the length direction of the roller way, so that the operation is simple and the adjustment precision is high.

[0057] Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art and related fields without creative work should belong to the protection scope of the present application. The structures, devices and operation methods not specifically described and explained in the present application are implemented according to the conventional means in the art, unless otherwise specified and limited.

Claims

1. A method of straightening a stainless steel sheet, characterized by, The method comprises the following steps: S1: heating the slab and rolling the heated slab; S2: solid solution heat treatment and quenching of the rolled plate; S3: shot blasting treatment of the quenched plate; S4: the length direction of the shot blasted plate is at a certain angle with the length direction of the roller way, and the plate enters the straightening machine for straightening treatment; S5: pickling and dressing of the straightened plate; In step S4, a centering device is installed on the front transmission roller way of the straightening machine, which is used to adjust the angle of the plate so that the length direction of the plate is at a certain angle with the length direction of the roller way. The plate is inclined to enter the straightening machine for straightening treatment through the centering device, so that the head or tail of the plate is inclined, and the contact line of the arc surface of the head or tail of the plate and the straightening roller is staggered, and the angle is related to the thickness of the plate: When the thickness h of the plate is 5≤h≤7mm, the angle is 26-30°; When the thickness h of the plate is 7 When the thickness h of the plate is 8 The stainless steel sheet is an austenitic stainless steel sheet with a thickness of ≤10mm. After quenching, the temperature of the plate is ≤150℃, and the unevenness of the steel sheet is ≤30mm / m.

2. The method of straightening a stainless steel sheet according to claim 1, characterized by, In S2, the quenching treatment specifically adopts a combined cooling method of spraying and water tank.

3. The method of claim 1, wherein the stainless steel sheet is a thin sheet. In S3, high-carbon steel pellets are used in the shot blasting process, and the pellet model is S280. After shot blasting, the plate finish is ASa2.

5.

4. A control system for carrying out the method of straightening a sheet of stainless steel according to any one of claims 1 to 3, characterized in that, The method comprises the following steps: An input module (10) is used to input the material number of the stainless steel sheet, generate corresponding size data after inputting the material number, and generate a control information to the corresponding module according to the size data; A control module (11) controls the corresponding station according to the control information. After the plate material number is input into the input module (10), the corresponding size data is generated by identifying the material number, and the corresponding control information is generated according to the size data, and the control information is transmitted to the control module (11). The control module (11) adjusts the angle between the length direction of the plate and the length direction of the roller way according to the control information.

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