Method for rolling silicon steel through 20-roller rolling mill with rolling medium being rolling oil

Abstract

The invention provides a method for rolling silicon steel by using a 20-roller rolling mill with rolling oil as a rolling medium, which comprises the following steps of: preheating a working roller to 100-120 DEG C by using the rolling oil as the rolling medium, then setting the reduction rate of the first pass to be 36-40%, and gradually reducing the reduction rates of other passes by 3-4% per pass, and carrying out reciprocating rolling on the 20-roller rolling mill, the total number of rolling passes is 5-6, rolling of silicon steel can be directly achieved on a 20-roller rolling mill with rolling oil as a rolling medium, and meanwhile the method is suitable for rolling of oriented silicon steel or non-oriented silicon steel. And the technological method is simple, a large amount of capital investment is not needed, and the rolling cost for rolling silicon steel through a 20-roller rolling mill can be greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of silicon steel product manufacturing, and relates to a method for rolling silicon steel using a 20-roller rolling mill with rolling oil as the rolling medium. The silicon steel specifically involved includes oriented silicon steel and non-oriented silicon steel, and the silicon steel grades involved include low grade, medium grade and high grade. Background Art

[0002] Due to product transformation and upgrading, existing steel mills need to realize silicon steel rolling on the 20-roll mills originally used for rolling stainless steel. The rolling medium used by these 20-roll mills for rolling stainless steel is rolling oil, but the rolling medium used by the 20-roll mills for rolling silicon steel at home and abroad is emulsion. If the rolling oil system is transformed into an emulsion system, it will require a large capital investment. Therefore, how to directly realize the rolling of silicon steel on a 20-roll mill with rolling oil as the rolling medium has become a technical problem that cannot be overcome at present. Summary of the invention

[0003] The purpose of the present invention is to provide a method for rolling silicon steel using a 20-roll mill with rolling oil as the rolling medium, so as to solve the technical problem of converting the rolling oil system of the 20-roll mill into an emulsion system, which requires a large capital investment.

[0004] To achieve its purpose, the present invention adopts the following technical solution: A method for rolling silicon steel using a 20-roll mill with rolling oil as the rolling medium, wherein the rolling oil is used as the rolling medium; the working rolls of the 20-roll mill are preheated to 100-120° C., the first pass reduction rate is set to 36-40%, and the other pass reduction rates are decreased by 3-5% per pass, and reciprocating rolling is performed on the 20-roll mill.

[0005] As a further preferred embodiment of the technical solution of the present invention, the rolling oil flow rate is 800-1500 L / min. When the rolling oil flow rate is lower than 800 L / min, insufficient lubrication will not only easily cause excessive wear or even locking of the roller bearings, but also the oil film between the working roll and the steel strip cannot be replenished in time, which may easily cause the oil film to rupture and produce scratch defects. When the rolling oil flow rate is higher than 1500 L / min, excessive rolling oil will rapidly reduce the temperature of the steel strip, which is not conducive to stable rolling.

[0006] Furthermore, the total number of rolling passes is 5 to 6. When the total number of rolling passes is less than 5, the reduction in a single pass is too large, which easily causes slippage between the working roll and the steel strip. When the total number of rolling passes is greater than 6, the reduction in a single pass is too small, and sufficient deformation friction heat cannot be generated, which is not conducive to rolling.

[0007] Furthermore, the target thickness of the silicon steel is 0.25-0.35 mm.

[0008] Furthermore, the silicon steel is oriented silicon steel or non-oriented silicon steel.

[0009] Furthermore, the silicon steel is low-grade, medium-grade or high-grade silicon steel.

[0010] The beneficial effects of the present invention are: The present invention uses rolling oil as rolling medium, preheats the working roll to 100-120°C, sets the first pass reduction rate to 36-40%, and decreases the reduction rate of other passes by 3-4% per pass, performs reciprocating rolling on a 20-roll mill, and the total number of rolling passes is 5-6. Silicon steel can be directly rolled on a 20-roll mill using rolling oil as rolling medium, and is also suitable for rolling oriented silicon steel or non-oriented silicon steel. The process is simple, does not require a large amount of capital investment, and can greatly reduce the rolling cost of silicon steel rolling using a 20-roll mill. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a physical picture of a silicon steel product produced by the method in Example 1 of the present invention; Figure 2 This is a physical picture of a silicon steel product produced by the method in Example 2 of the present invention (a plate cut from a steel coil); Figure 3 This is a physical picture of a silicon steel product produced by the method in Example 3 of the present invention. DETAILED DESCRIPTION

[0012] In order to make the purpose and technical solution of the present invention more clear, the present invention is further described in detail by specific embodiments below. It should be understood that the specific embodiments described here are only used to explain the present invention and are not used to limit the present invention.

[0013] Example 1 In order to realize the rolling of medium-grade silicon steel in a 20-high mill with rolling oil as the rolling medium, the normalized 35W470 grade non-oriented silicon steel (thickness of 1.970 mm) with a silicon content of 1.81% and an aluminum content of 0.47% was reciprocatingly rolled on a 20-high mill with a target thickness of 0.350 mm for a total of 5 passes, including the following steps: (1) Preheat the working roll to 100°C; (2) Set the rolling oil flow rate to 1500L / min; (3) First-pass rolling, the first-pass reduction ratio is set to 38%; (4) The reduction rates of the other passes are: 33% for the second pass, 28% for the third pass, 24% for the fourth pass, and 21.8% for the fifth pass. The silicon steel product is shown in the figure below: Figure 1As shown, the performance parameters of silicon steel are shown in Table 1.

[0014] Example 2 In order to realize the rolling of high-grade silicon steel with a 20-roll mill using rolling oil as the rolling medium, the normalized 30AV1700 grade non-oriented silicon steel (thickness 1.970 mm) with a silicon content of 3.03% and an aluminum content of 0.52% and a target thickness of 0.300 mm was reciprocatingly rolled on a 20-roll mill for a total of 5 passes, including the following steps: (1) Preheat the working roll to 110°C; (2) Set the rolling oil flow rate to 1000L / min; (3) First-pass rolling, the first-pass reduction ratio is set to 38%; (4) The reduction rates of the other passes are: 35% for the second pass, 31% for the third pass, 28% for the fourth pass, and 24% for the fifth pass. The silicon steel product is shown in the figure below. Figure 2 As shown, the performance parameters of silicon steel are shown in Table 1.

[0015] Example 3 In order to realize the rolling of high-grade silicon steel with a 20-high mill using rolling oil as the rolling medium, the silicon content is 3.26%, the aluminum content is 0.68%, and the normalized 25W270 grade non-oriented silicon steel (thickness is 1.970mm) with a target thickness of 0.250mm is reciprocatingly rolled on a 20-high mill, with a total of 6 passes, including the following steps: (1) Preheat the working roll to 120°C; (2) Set the rolling oil flow rate to 800L / min; (3) First-pass rolling, the first-pass reduction ratio is set to 40%; (4) The reduction rates of the other passes are: 36% for the second pass, 31% for the third pass, 26% for the fourth pass, 22% for the fifth pass, and 17% for the sixth pass. The silicon steel product is shown in the figure below. Figure 3 As shown, the performance parameters of silicon steel are shown in Table 1.

[0016] Table 1 Silicon steel product performance parameters

[0017] Table 1 Data Description: (1) Iron loss P 1.5 / 50It refers to the loss of silicon steel material when it is magnetized to 1.5T under 50Hz alternating magnetic field, and the unit is W / kg (watt / kilogram). The lower the iron loss, the better the magnetic properties of the silicon steel material. The national standard GB / T 2521.1-2016 stipulates that the iron loss P1.5 / 50 of non-oriented silicon steel W470 is ≤4.7W / kg, and the iron loss P1.5 / 50 of W270 is ≤2.7W / kg. The industry generally stipulates that the iron loss P1.5 / 50 of AV1700 is ≤4.78W / kg. The iron loss P1.5 / 50 of silicon steel products in Examples 1-3 of the present invention is ≤4.78W / kg. 1.5 / 50 All meet the requirements.

[0018] (2) Magnetic induction intensity B50 refers to the magnetic induction intensity value of silicon steel sheet when the magnetic field intensity reaches 50A / m in the magnetic performance test of silicon steel sheet. The unit is Tesla (T). The higher the magnetic induction intensity, the better the magnetic conductivity. The national standard GB / T2521.1-2016 generally stipulates that the magnetic induction intensity B50 of non-oriented silicon steel 50 ≥1.5T requirement, the magnetic induction intensity B50 of the silicon steel products in Examples 1-3 of the present invention all meet the requirement.

Claims

1. A method for rolling silicon steel using a 20-high rolling mill with rolling oil as the rolling medium, characterized in that: Rolling oil is used as the rolling medium; the working rolls of the 20-roll mill are preheated to 100-120°C, the reduction rate of the first pass is set to 36-40%, and the reduction rates of other passes are reduced by 3-5% per pass, and reciprocating rolling is performed on the 20-roll mill.

2. A method for rolling silicon steel using a 20-high rolling mill with rolling oil as the rolling medium according to claim 1, characterized in that: The rolling oil flow rate is 800-1500 L / min.

3. A method for rolling silicon steel using a 20-high rolling mill with rolling oil as the rolling medium according to claim 1, characterized in that: The total number of rolling passes is 5 to 6.

4. A method for rolling silicon steel using a 20-high rolling mill with rolling oil as the rolling medium according to any one of claims 1 to 3, characterized in that: The target thickness of the silicon steel is 0.25 to 0.35 mm.

5. A method for rolling silicon steel using a 20-high rolling mill with rolling oil as the rolling medium according to claim 4, characterized in that: The silicon steel is oriented silicon steel or non-oriented silicon steel.

6. A method for rolling silicon steel using a 20-high rolling mill with rolling oil as the rolling medium according to claim 5, characterized in that: The silicon steel is low-grade, medium-grade or high-grade silicon steel.

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