Disposal method for solving on-machine slipping problem of rough rolling working roll

Abstract

The invention relates to a disposal method for solving the on-machine slipping problem of a rough rolling working roller. The disposal method comprises the following steps that (1) the material of the working roller is upgraded into the material of alloy forged steel; (2) the roller grinding process is adjusted, and the roller surface roughness is gradually increased to be larger than 5 micrometers; (3) working roller water sealing adjustment, wherein a water guide groove is formed in the edge of a working roller water sealing protection plate; 4) optimizing the cooling water flow of the working roll; (5) the rolling process is adjusted, specifically, the rolling reduction of a rolling mill R1 is adjusted, the two-pass biting speed of R2 is adjusted, and the two-pass acceleration of R2 is adjusted; the method has the beneficial effects that the roller material is improved, the strength of the working roller is improved, the roughness of the rough rolling working roller is increased, the cooling water flow is reduced, the influence of steel billet biting conditions is reduced, the slipping problem of the rough rolling working roller is reduced, the hot crack damage loss caused by the slipping problem of the roller is reduced, and the working efficiency of the rough rolling working roller is improved; the working time of the rough rolling working roller is prolonged, the yield is increased and the product profit is increased.

Description

Technical Field

[0001] The invention relates to the technical field of steel rolling technology, and in particular to a method for solving the problem of steel rolling working rolls slipping on a machine. Background Art

[0002] During the hot strip rolling process, the rough rolling area adopts the R1 double-roll mill + R2 four-roll mill mode. Due to the combined factors of large rough rolling reduction, unclean scale removal, and high temperature of hot strip rolling, the billet is prone to generate iron oxide scale, and the friction coefficient of the billet surface is reduced, causing relative sliding between the roll and the billet surface, causing the billet to slip. In order to reduce the impact of rough rolling roll slippage accidents, the production line adopts the 3+5 mode of reduced speed rolling in the rough rolling area in the early stage of rough rolling working roll replacement. Compared with the conventional 3+3 rolling mode, the R2 mill has 2 more rolling passes, which reduces the production efficiency of the production line and restricts the overall improvement of the production line capacity.

[0003] When the steel billet slips on the roll, the high-temperature red steel state of the steel billet is in direct contact with the roll body. Under the action of thermal stress, thermal crack defects are easily generated on the roll body, causing roll damage. The production line needs to be shut down to replace the roll, resulting in unplanned shutdown. If the roll is replaced without stopping the line; the damaged roll continues to be used for rolling on the machine, and the thermal cracks generated on the roll body expand under the action of rolling force and thermal stress, which is very likely to cause roll accidents on the machine. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides a method for solving the problem of rough rolling working rolls slipping on the machine, which reduces the occurrence of rough rolling working roll rolling slipping problems by upgrading the material, adjusting the grinding process, adjusting the working roll water seal, adjusting the working roll cooling water flow and adjusting the steel rolling process, reduces the hidden dangers of thermal crack damage caused by working roll slipping, eliminates the bottleneck problem of production line speed reduction after replacement of rough rolling working rolls, improves the production line capacity, and creates more profit space.

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

[0006] A method for solving the problem of rough rolling work rolls slipping on the mill, the rough rolling work rolls include R1 double-roll mill work rolls and R2 four-roll mill work rolls, and the method comprises the following steps:

[0007] S1 material upgrade

[0008] Upgrade the original high-chromium steel material of the R1 working roll to high-strength alloy forged steel;

[0009] S2 Roller Grinding Process Adjustment

[0010] 1) The grinding wheel speed of the rough rolling work roll was gradually adjusted from 35m / s to 20m / s and 10m / s, and the roll surface roughness was gradually increased to more than 4μm;

[0011] 2) The intermediate grinding and finishing knife grinding steps are cancelled, the direct feed of the grinding wheel is gradually increased from 0.04mm to 0.08mm, and the roller surface roughness is gradually increased to more than 5μm;

[0012] S3 working roll water sealing adjustment

[0013] A water guide groove is added to the edge of the working roll water sealing guard plate, and the scraper adopts a double-strip superimposed structure of upper and lower layers;

[0014] S4 optimizes the cooling water flow of the working roll

[0015] Adjust the cooling water flow of R2 working roll to reduce by 15% to 20%;

[0016] S5 rolling process adjustment

[0017] 1) Improve the rolling force of the R1 stand and increase the reduction of the slab in the R1 stand;

[0018] 2) Adjust the second pass bite speed of R2, reduce the bite speed by 10% to 15%, adjust the second pass acceleration of R2, reduce the second pass acceleration by 10% to 15%.

[0019] Furthermore, in step S3, the wiper blade adopts a stacked structure of rubber and resin.

[0020] Furthermore, in step S2, the roller grinding process adjustment is applicable to the joint increase of the grinding roughness of the R1 two-roller stand, the R2 four-roller stand, the upper and lower support rolls and the working rolls.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. Improve the material of the roll, enhance the strength of the working roll, eliminate the toughness of the joint between the roll body and the roll neck, improve the comprehensive safety factor of the roll, reduce the thermal crack damage caused by the roll slip problem, improve the working efficiency of the rough rolling work roll, extend the working time of the rough rolling work roll, increase production, and increase product profits.

[0023] 2. Increase the roughness of the rough rolling working roll, reduce the cooling water flow, reduce the impact of the billet biting conditions, reduce the occurrence of rough rolling working roll slippage, avoid direct contact between the red steel billet and the working roll, reduce the risk of billet damaging the working roll, and improve the utilization rate of the working roll.

[0024] 3. The roughness of the rough rolling work roll is large, which avoids the slipping problem in the early stage of replacing the rough rolling work roll, eliminates the bottleneck problem of production line slowing down after the replacement of the rough rolling work roll, and the production line is produced at full speed, which improves the production line capacity and creates more profit space. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the working roll structure of the present invention.

[0026] Figure 2 This is a front view of the working roll described in the present invention.

[0027] In the figure: 1. Working roller 2. Frame 3. Water guide trough 4. Upper scraper 5. Lower scraper 6. Bolt DETAILED DESCRIPTION

[0028] The specific embodiments of the present invention are further described below:

[0029] like Figure 1-Figure 2 As shown, a method for solving the problem of rough rolling work roll slipping in the mill is provided, wherein the rough rolling work roll 1 comprises an R1 double-roll mill work roll 1 and an R2 four-roll mill work roll 1, and the method comprises the following steps:

[0030] S1 material upgrade

[0031] Upgrade the original high-chromium steel material of R1 working roll 1 to high-strength alloy forged steel material;

[0032] S2 Roller Grinding Process Adjustment

[0033] 1) The grinding wheel speed of the rough rolling work roll 1 was gradually adjusted from 35m / s to 20m / s and 10m / s, and the roll surface roughness was gradually increased to more than 4μm;

[0034] 2) The intermediate grinding and finishing knife grinding steps are cancelled, the direct feed of the grinding wheel is gradually increased from 0.04mm to 0.08mm, and the roller surface roughness is gradually increased to more than 5μm;

[0035] S3 working roll water sealing adjustment

[0036] A water guide groove 3 is added to the edge of the working roll water sealing guard plate, and the scraper plate adopts a double-strip superimposed structure of an upper scraper plate 4 and a lower scraper plate 5, which are connected to the water sealing guard plate by bolts 6;

[0037] S4 optimizes the cooling water flow of the working roll

[0038] Adjust the cooling water flow of R2 working roll 1 to reduce by 15% to 20%;

[0039] S5 rolling process adjustment

[0040] 1) Improve the rolling force of R1 stand 2, increase the reduction of slab in R1 stand 2, and realize full speed "3+3" mode rolling in the initial rolling period of the rough rolling area;

[0041] 2) Adjust the R2 second pass bite speed from 3.2m / s to 3.0m / s, and adjust the R2 second pass acceleration from 1m / s 2 Reduced to 0.9m / s 2 .

[0042] Furthermore, in the step S3, the wiper blades are made of a stacked structure of rubber and resin, the upper wiper blade 4 is made of rubber, and the lower wiper blade 5 is made of resin.

[0043] Furthermore, in the step S2, the roller grinding process adjustment is applicable to the synchronous adjustment of the R1 two-roller frame 2, the R2 four-roller frame 2, the upper and lower support rolls and the working roll 1, so as to reduce the probability of slippage between the rough rolling working roll 1 and the billet by jointly increasing the grinding roughness.

[0044] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0045] The following examples are implemented on the premise of the technical solution of the present invention, and provide detailed implementation methods and specific operating processes, but the protection scope of the present invention is not limited to the following examples. The methods used in the following examples are conventional methods unless otherwise specified.

[0046] [Example]

[0047] The material of R1 working roll 1 is alloy forged steel.

[0048] During the grinding process of rough rolling work roll 1, the grinding wheel speed was gradually reduced from 35m / s to 10m / s, and the roll surface roughness was gradually increased to Ra0.4μm.

[0049] The direct feed of the grinding wheel gradually increased from 0.04mm to 0.08mm, and the roller surface roughness gradually increased to Ra0.53μm.

[0050] A water guide groove is added to the edge of the guard plate of the rough rolling working roll 1, and the cooling water of the rolling roll overflows along the groove. The scraper 4 of the rough rolling working roll guard plate 3 adopts an upper and lower layer stacking structure. The scraper 4 made of rubber and resin is superimposed on the roll surface on one side of the working roll to ensure the scraping effect when used on the machine.

[0051] Reduce the cooling water flow of R2 working roll by 15%.

[0052] Increase the reduction of R1 rolling mill stand 2, R2 second pass bite speed 3.0m / s, R2 second pass acceleration 0.9m / s 2 , adjust the rough rolling area to maintain full speed 3+3 mode rolling in the initial stage.

[0053] After the rough rolling working rolls are replaced, they can be rolled directly at full speed without slipping of the steel billet. The production line efficiency is improved and the output is increased.

Claims

1. A method for solving the problem of rough rolling work rolls slipping on the mill, wherein the rough rolling work rolls include R1 double-roll mill work rolls and R2 four-roll mill work rolls, characterized in that: The disposal method comprises the following steps: S1 material upgrade Upgrade the original high-chromium steel material of the R1 working roll to high-strength alloy forged steel; S2 Roller Grinding Process Adjustment 1) The grinding wheel speed of the rough rolling work roll was gradually adjusted from 35m / s to 20m / s and 10m / s, and the roll surface roughness was gradually increased to more than 4μm; 2) The intermediate grinding and finishing knife grinding steps are cancelled, the direct feed of the grinding wheel is gradually increased from 0.04mm to 0.08mm, and the roller surface roughness is gradually increased to more than 5μm; S3 working roll water sealing adjustment A water guide groove is added to the edge of the working roll water sealing guard plate, and the scraper adopts a double-strip superimposed structure of upper and lower layers; S4 optimizes the cooling water flow of the working roll Adjust the cooling water flow of R2 working roll to reduce by 15% to 20%; S5 rolling process adjustment 1) Improve the rolling force of the R1 stand and increase the reduction of the slab in the R1 stand; 2) Adjust the second pass bite speed of R2, reduce the bite speed by 10% to 15%, adjust the second pass acceleration of R2, reduce the second pass acceleration by 10% to 15%.

2. A method for solving the problem of rolling mill work roll slipping in the machine according to claim 1, characterized in that: The wiper blade in step S3 is made of a laminated structure of rubber and resin.

3. The method for solving the problem of the working roll slipping in the mill according to claim 1 is characterized in that: The roller grinding process adjustment in S2 is applicable to the joint increase of the grinding roughness of the R1 two-roller stand, the R2 four-roller stand, the upper and lower support rolls and the working rolls.

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