A method for preparing a unit for producing silicon steel

Abstract

The present application belongs to the technical field of silicon steel smelting, and particularly relates to a method for producing silicon steel based on a preparation unit, comprising the following contents: (1) the tail of the previous coil is centered and pressed in the outlet section, the tail is positioned in the double cutting shear, the head of the next coil is centered and pressed in the inlet section, the head is positioned in the double cutting shear, the double cutting shear is cut, the plate of the welding machine is moved and spliced, and the composite welding is performed; (2) the previous coil is unloaded, the belt coil helper runs to the working position, the leading tape is wound on the coiler, and the EPC is put into two programs, one is an automatic mode, and the other is a manual mode. The EPC function of the head of each coil defaults to the automatic input mode, the EPC is automatically input, and the manual input function needs to be started after the "manual mode" is clicked in the operation picture. The EPC is manually input; (3) the width of the base material is 1000-1300 mm, and the leading tape with a width of 1000 mm is adopted. The present application optimizes the welding process, designs the input condition of the EPC centering function of the coiler, and improves the production efficiency of the unit and the yield of the rolling mill.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of silicon steel smelting, and particularly relates to a method for producing silicon steel based on a preparation unit. BACKGROUND

[0002] Ultra-high grade non-oriented silicon steel and high magnetic induction oriented silicon steel are mainly produced by single stand rolling mill. Due to high silicon content and high brittleness, the rolling difficulty is great, the strip is easy to break, and the single stand rolling mill has the characteristics of reversible rolling, so the head and tail lead strips (unrolled sections) are long, and the yield is low. Therefore, when the twenty-roll rolling mill is used to roll the silicon steel with a silicon content of more than 3.0%, a preparation unit process is added before rolling. The preparation unit mainly welds the lead strip (usually Q235 after pickling) to the head and tail of the steel coil after (normalizing) pickling and preheats the steel coil to improve the rolling stability and rolling yield of the cold rolling process. The preparation unit is composed of double uncoilers (one for uncoiling the silicon steel coil and one for uncoiling the lead strip coil), pinch straightening machines, slitting shears (three sets, one set for each uncoiler, one set before the coiler), side guides (two sets, one set behind each uncoiler), laser-arc composite welding machines, tension rollers, electromagnetic induction heating devices, tension coilers, and centering devices (one set of CPC device behind each uncoiler, and one set of EPC device at the coiler). The main function of the preparation unit is to heat the steel coil to 100-150 DEG C, weld the lead strip to the head and tail, and align the steel coil. (Note: Due to the characteristics of the twenty-roll single stand rolling mill, there are 8-12 meters of head and tail that cannot be rolled, which greatly affects the yield.) The welding machine process is as follows: front coil tail, rear coil head, shearing, centering, welding, and edge treatment of the weld. The current design of the preparation unit has certain defects, mainly in the following aspects:

[0003] (1) After welding the lead strip, the crescent shears process the edge of the weld, but the strip is not heated before the edge is processed. Due to high silicon content and high brittleness, the edge is easy to form invisible cracks or even cracks during edge processing, causing the base material to be brittle during rolling.

[0004] (2) The width of the base material is between 960 mm and 1280 mm, and the width of the lead strip is only 1000 mm, 1100 mm, and 1200 mm. The welding machine is a centering welding machine (the centers of the base material and the lead strip are aligned), and the width of the lead strip is different from that of the base material. The two edges of the weld are not aligned, and the EPC is aligned on one side, causing the head to be rolled unevenly after passing through the weld, and the rolling mill cannot roll the unevenly rolled material.

[0005] (3) The preparation unit supplies raw materials for 3-4 single stand rolling mills with different width specifications, and the lead strip coils with different widths are replaced frequently, which reduces the production efficiency of the unit. The base material with unevenly rolled head and tail cannot be normally produced during rolling, and the cold rolling yield is low. SUMMARY

[0006] The application aims to provide a method for preparing a machine group to produce silicon steel, which solves the problems of hidden cracks and even cracks in the edge during edge digging, uneven and different width of the two edge parts of the weld, frequent replacement of the strip guide roll, and low production efficiency of the machine group.

[0007] To achieve the above-mentioned purpose, the application adopts the following technical solutions:

[0008] A method for preparing a machine group to produce silicon steel, comprising the following contents:

[0009] (1) The outlet section is centered and the tail of the previous roll is pressed, the tail is positioned in the double cutting shear, the inlet section is centered and the head of the next roll is pressed, the head is positioned in the double cutting shear, the double cutting shear is cut, the welding machine moves and splices the seam, and the composite welding is performed;

[0010] (2) The previous roll is unloaded, the belt roll helper runs to the working position, the strip guide is wound on the coiler, and the EPC is put into two programs, one is automatic mode and the other is manual mode. The selection key of the EPC function input mode is added to the HMI picture, that is, the selection of manual mode and automatic mode; the EPC function of the head of each roll defaults to automatic input mode, the machine group runs, the length is automatically recorded, the EPC is automatically input, and the manual input function needs to be started after clicking "manual mode" in the operation picture, and the EPC is manually input.

[0011] (3) The width of the base material is 1000-1300mm, and the strip guide with a width of 1000mm is used.

[0012] Preferably, the welding machine used in (1) is a laser-arc composite welding machine.

[0013] Preferably, the composite welding speed in (1) is 1.6-2.3m / min, the laser power is 4.0-5.0kW, the welding head pressure is 30%-50%, the gap between the pressing plates is 0.07-0.12mm, and the induction power is 10-15kW.

[0014] Preferably, the two program modes in the (2) are applied: the manual mode is applied to the strip length of the leading strip which is not 7.5 m, and the HMI screen is manually operated to input the EPC function according to the actual position of the weld; one is that when the tail length of the leading strip of the previous coil is less than a normal leading strip length, the whole winding is manually completed; the other is that the leading strip length is different from the automatic running program due to equipment failure and the like; the automatic mode is applied: under normal circumstances, the unit runs at the threading speed after welding, when the leading strip of 7.5 m (the center position of the tail of the previous coil and the head of the next coil) is located at the 3# slitting shear (the slitting shear before the coiler), the unit stops, the pinch roll before the 3# slitting shear tightens, the 3# slitting shear cuts the strip, the tail of the previous coil is coiled and the coil is unloaded. The head of the next coil continues to thread and is wound on the coiler using the belt coil helper to build the coil. After that, when the unit running length reaches 8 m (the length is counted from the cutting of the 3# slitting shear), the weld just passes through the EPC photoelectric tube, and the PLC issues the instruction of inputting the EPC function after meeting the two conditions of the coiling tension and the length > 8 m.

[0015] Compared with the prior art, the present application has the following beneficial effects:

[0016] (1) The present application removes the edge digging of the crescent shear and does not dig the edge at the weld, although it brings the risk of weld breakage, but through the optimization of the process flow and the change of the welding parameters, the problem of weld breakage is solved, the problem of the formation of invisible cracks or even cracks in the edge during the edge digging is avoided, the brittle fracture of the base material during the coiling of the rolling mill is avoided, and the consumption of the crescent shear and the maintenance cost of the equipment are saved;

[0017] (2) The present application optimizes the parameters such as the strip length, the center position distance of the tail of the previous coil and the head of the next coil leading strip, the running length, the coiling tension and the length, designs the conditions of inputting the EPC function, and programs the control program into the PLC, so that the problem of the misalignment of the coiling after the weld when the leading strip and the base material are different in width is solved;

[0018] (3) The present application uses a narrow strip as the leading strip, solves the problem of frequent replacement of leading strips of different widths due to the change of the base material width, improves the operation rate of the preparation unit, and saves the use amount of the leading strip. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a schematic diagram of the preparation unit in the embodiment of the present application. DETAILED DESCRIPTION

[0020] The technical solutions of the present application will be described below in combination with the embodiments. Embodiment 1

[0021] The present embodiment takes the ultra-high grade non-oriented silicon steel with a width of 1100 mm and a thickness of 2.3 mm and the Q235A leading strip material with a width of 1000 mm and a thickness of 2.3 mm as examples, and is based on the preparation unit production as shown in Figure 1 . .

[0022] A method for producing silicon steel based on a preparation unit, comprising the following contents:

[0023] (1) Leading strip roll unwinding and threading: the leading strip roll head is unwound by a leading strip roll unwinder and sent to a No. 1 pinch straightener, the leading strip after the head is straightened is centered by a No. 1 side guide roll, reaches a No. 2 pinch straightener through a No. 1 slitting shear and a No. 2 pinch straightener, and reaches a No. 2 slitting shear. The leading strip after the head is cut is sent to a welding machine, and the leading strip roll head is automatically stopped at the center of the welding machine. At this time, the length of the leading strip to the No. 1 slitting shear is about 15 m;

[0024] (2) The specific steps and parameters of leading strip welding are as follows: the tail of the previous roll is centered and pressed out, the tail is positioned in the double shear, the head of the next roll is centered and pressed in, the head is positioned in the double shear, the double shear is cut, the welding plate is moved and the joint is spliced, and the welding parameters are: welding speed 2 m / min, laser power 4.5 kW, welding head pressure 33%, plate gap 0.1 mm, and induction power 12 kW;

[0025] (3) After the weld is checked and qualified, the EPC function of the head of each roll is automatically put into mode by default, the leading strip is cut at the No. 1 slitting shear, the unit is operated, the length is automatically recorded, the EPC is automatically put into, and the unit is operated at the threading speed; the tail of the leading strip is stopped at the center of the welding machine, and then the next normal roll starts to unwind and thread;

[0026] (4) The head of the next normal roll is sent to the No. 2 pinch straightener by the normal roll unwinder, the head is centered at the No. 2 side guide roll after the straightening head, and then sent to the No. 2 slitting shear for cutting the head. The head is automatically positioned to the welding machine after the cutting of the head, and welded together with the tail of the leading strip; the specific welding steps and parameters are the same as step (2);

[0027] (5) After welding, the unit is operated at the threading speed, the EPC function is automatically closed before the weld reaches the EPC detection device, when the leading strip material is located at the No. 3 slitting shear at 7.5 m, the unit is stopped, the pinch roller in front of the No. 3 slitting shear is tightened, the tension roller output torque keeps the tension of the strip steel in the electromagnetic induction heating strip, and the No. 3 slitting shear cuts the strip steel;

[0028] (6) After the front coil is uncoiled, the rear coil is coiled by the belt coiler, and the running length of the unit reaches 8 m (the length is counted from the cutting of the No. 3 slitting shear), the weld just passes through the EPC photoelectric tube, and the PLC issues the command of EPC function input after meeting the two conditions of coiling tension and length > 8 m, and the unit is accelerated to the normal speed. The electromagnetic induction heater works automatically throughout the process to heat the strip;

[0029] (7) When the strip runs to the tail throwing length, the unit is decelerated to the threading speed, the pinch roll of the No. 2 pinch straightening machine is pressed down to assist in tail throwing, and after the tail is cut by the No. 2 slitting shear, the unit is run at low speed to the center of the welder and stopped, waiting for the next section of the leading strip. Example 2

[0030] The base material of this example is high-magnetic-susceptibility oriented silicon steel with a width of 1030 mm and a thickness of 2.5 mm, and the leading strip material is Q235A with a width of 1000 mm and a thickness of 2.5 mm, based on the preparation unit production as shown in Figure 1 .

[0031] A method for producing silicon steel based on a preparation unit, having the following steps:

[0032] (1) Leading strip coil unwinding and threading: the leading strip coil head is unwound by the leading strip coil unwinder and sent to the No. 1 pinch straightening machine, the leading strip after straightening the head is centered by the No. 1 side guide roll, and reaches the No. 2 slitting shear through the No. 1 slitting shear and the No. 2 pinch straightening machine. The cut head leading strip is sent to the welder, and the leading strip coil head is automatically stopped at the center of the welder, at this time the leading strip length at the No. 1 slitting shear is about 15 m;

[0033] (2) The specific steps and parameters of leading strip welding are as follows: the outlet section is centered and pressed tightly, the tail of the front coil is positioned in the double shear, the inlet section is centered and pressed tightly, the head of the rear coil is positioned in the double shear, the double shear is cut, the welder pressure plate is moved and the seam is spliced, and the composite welding is performed; the welding parameters are: welding speed 1.8 m / min, laser power 4.7 kW, welding head pressure 35%, pressure plate gap 0.1 mm, induction power 14 kW;

[0034] (3) After the weld is checked and qualified, the length of the leading strip is required to be 6 m, not 7.5 m, the operator clicks "manual mode" in the operation picture, the unit runs at a certain distance after threading at the threading speed, and then the unit is stopped, the No. 1 slitting shear cuts the leading strip, or the leading strip coil is used up without cutting; the tail of the leading strip is stopped at the center of the welder, and then the normal coiling of the rear coil starts to uncoil and thread;

[0035] (4) The tail of the normal coil is sent into the No. 2 pinch straightener by the normal coil uncoiler, and after the straightening, the tail is centered at the No. 2 side guide roll, and then is sent to the No. 2 slitting shear to cut the tail, and after the cutting, the tail is automatically positioned to the welding machine, and is welded with the leading tail, and the specific welding steps and parameters are the same as those in step (2);

[0036] (5) After the welding, the unit runs at the threading speed, and before the weld reaches the EPC detection device, the EPC function is automatically closed, the length of the leading strip is manually adjusted, when the leading strip 6 m is located at the No. 3 slitting shear, the unit stops, the front pinch roll of the No. 3 slitting shear is tightened, the tension roll output torque keeps the strip tension in the electromagnetic induction heating strip, and the No. 3 slitting shear cuts the strip;

[0037] (6) After the front coil is uncoiled, the rear coil is coiled by the belt coiler, the EPC function is selected in the manual mode, the unit runs after the tension is built, the weld reaches the EPC photoelectric detection device, the HMI screen is manually operated to input the EPC function, the unit runs at the normal speed, and the electromagnetic induction heater automatically works to heat the strip;

[0038] (7) When the strip runs to the tail throwing length, the unit runs at the threading speed, the pinch roll of the No. 2 pinch straightener is pressed down to assist the tail throwing, after the tail is cut by the No. 2 slitting shear, the unit runs at a low speed to the center of the welding machine and stops, and waits for the next leading strip.

Claims

1. A method for producing silicon steel based on a preparatory unit, characterized in that, Includes the following: (1) The outlet section is centered and the tail of the previous roll is pressed, and the tail of the roll is positioned inside the double cutter. The inlet section is centered and the head of the next roll is pressed, and the head of the roll is positioned inside the double cutter. The double cutter cuts, the welding machine pressure plate moves and splices the seam, and composite welding is performed. (2) After the previous roll is unloaded, the belt winding aid moves to the working position, and the lead belt is wound on the winding machine. The EPC input adds two programs: one is automatic mode and the other is manual mode. The HMI screen adds a selection key for the EPC function input mode, that is, the selection of manual mode and automatic mode. The default EPC function input mode for each roll head is automatic input mode. The unit runs, automatically records the length, and automatically inputs EPC. The manual input function needs to be started manually by clicking the manual mode on the operation screen. The two program modes are applied as follows: The manual mode is used when the lead belt length is not 7.5m. The operator manually operates the HMI screen to input the EPC function according to the actual position of the weld. One is when the lead belt tail length is less than a normal lead belt length, all of them need to be manually wound. The other is when the equipment failure causes the lead belt length to be different from the length in the automatic operation program. Automatic mode is applied as follows: After welding, the unit runs at the belt threading speed. When the lead belt is 7.5m in the center of the lead belt tail of the previous roll and the lead belt head of the next roll. When the slitting shear is located at m in front of the coiler, the unit stops, the clamping rollers in front of the slitting shear tighten, the slitting shear cuts the strip steel, the front coil of strip steel is wound up and unwound; the head of the next coil continues to be threaded and is wound onto the coiler using a belt winding aid, tension is built, and then when the unit's running length reaches 8m, the length is counted from the cut by the slitting shear. The weld seam just passes the EPC photocell, and the PLC issues the command to activate the EPC function after the two conditions of winding tension and length > 8m are met. (3) For base material width specifications of 1000-1300mm, a 1000mm wide guide strip is used.

2. The method for producing silicon steel based on a preparatory unit according to claim 1, characterized in that, The welding machine used in (1) is a laser-arc hybrid welding machine.

3. The method for producing silicon steel based on a preparatory unit according to claim 2, characterized in that, In (1), the composite welding speed is 1.6-2.3 m / min, the laser power is 4.0-5.0 kW, the welding head pressure is 30%-50%, the pressure plate gap is 0.07-0.12 mm, and the induction power supply power is 10-15 kW.

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