A control method for the outlet pinch roller of a width setting machine

Abstract

The present invention discloses a control method for the outlet pinch rollers of a width setting machine. A slab actual position detection device is added behind the outlet pinch rollers of the width setting machine to detect whether the slab passes through the outlet pinch rollers. The slab actual position detection device transmits the detection data to the basic automation computer of the width setting machine. After confirming that the slab passes through the upper and lower pinch rollers at the outlet, the basic automation computer of the width setting machine switches the upper and lower outlet pinch rollers to pressure control at the same time, and the upper and lower pinch rollers at the outlet and the lower pinch rollers at the outlet search for the upper and lower surfaces of the slab. When the pressure of the lower pinch roller at the outlet rises to the set pressure, the lower pinch roller at the outlet is switched to position control, and the upper pinch roller at the outlet maintains pressure control. The present invention adds a slab actual position detection device at the outlet of the width setting machine, changes the control mode of the outlet pinch rollers of the width setting machine, reduces the slipping of the slab in the width setting machine, and reduces the damage to the roller surface and mechanical equipment when the slab is fed into the steel.

Description

Technical Field

[0001] The invention relates to a hot rolling process, and more particularly to a method for controlling an outlet pinch roller of a width setting machine. Background Art

[0002] Please combine Figure 1 As shown, the sizing press is a machine that moves the module 2 back and forth in the width direction of the slab 1, and moves the slab 1 forward (see Figure 1 The device is used to reduce the width of the slab 1 by hitting the side of the slab 1 during the operation (in the direction of the X arrow in the figure) or when the slab stops after running a certain distance. The width setting machine can reduce the continuous casting width specification, improve the width control accuracy and reduce the head and tail cutting loss by controlling the shape after side pressing.

[0003] Please combine Figures 2 to 4 As shown, the control method of the exit pinch rollers (including the exit upper pinch roller 4 and the exit lower pinch roller 3) of the existing width setting machine is as follows:

[0004] 1) The heating furnace draws steel, and the process machine sends the calculated thickness H of the slab before width setting and the calculated thickness H1 of the slab after width setting to the basic automation computer of the width setting machine;

[0005] 2) The basic automation computer of the width setting machine calculates the elevation position EX LPR POS of the lower pinch roller 3 at the outlet according to the calculated thickness H of the slab before width setting, the calculated thickness H1 of the slab after width setting and formula 1:

[0006] EX LPR POS=EX LPR ZERO POS-(H1-H) / 2 Formula 1;

[0007] 3) The basic automation computer of the width setting machine calculates the roller gap EX PR GAP of the outlet pinch rollers according to the calculated thickness H1 of the slab after width setting and formula 2 (that is, the roller gap between the outlet upper pinch roller 4 and the outlet lower pinch roller 3 when the outlet lower pinch roller 3 is at the elevation position):

[0008] EX PR GAP = H1-a Formula 2;

[0009] 4) When the slab 1 passes through the outlet pinch rollers, if the actual thickness h1 of the slab after width setting is larger than the roller gap of the outlet pinch rollers, the slab 1 will have a certain impact on the outlet upper pinch rollers 4, and the pressure of the outlet upper pinch rollers 4 will increase;

[0010] When the pressure of the outlet upper pinch roller 4 is ≥50KN, the basic automatic calculation of the width setting machine determines that the slab 1 has been bitten into the outlet pinch roller, and the outlet upper pinch roller 4 will be switched from position control to pressure control;

[0011] When the pressure of the outlet upper pinch roller 4 is less than 50KN, the basic automatic calculation of the width setting machine determines that the tail of the slab 1 has passed the outlet pinch roller. The outlet upper pinch roller 4 is raised to 290mm, and the outlet lower pinch roller 3 is set to EX LPR ZERO POS;

[0012] 5) End.

[0013] In the above formula 1 and formula 2:

[0014] H is the calculated thickness of the slab before width determination;

[0015] H1 is the calculated thickness of the slab after the width is fixed;

[0016] h1 is the actual thickness of the slab after width setting;

[0017] EX LPR ZERO POS is the zero position of the lower pinch roller at the outlet;

[0018] a=10mm.

[0019] The most common fault during the use of the width setting machine is slippage, and a considerable part of it is caused by the unreasonable control method of the lower pinch roller 3 at the outlet. On the one hand, the calculated thickness H1 of the slab after width setting is obtained through theoretical calculation, and the deformation of the slab 1 is not completely linear, and it is often the case that the calculated thickness H1 of the slab after width setting is greater than or less than the actual thickness h1 of the slab after width setting.

[0020] If the calculated thickness H1 of the slab after width setting is greater than the actual thickness h1 of the slab after width setting, the elevation position of the lower pinch roller 3 at the outlet will be set too low, and the lower pinch roller 3 at the outlet will not be able to contact the lower surface of the slab 1, causing slippage.

[0021] If the calculated thickness H1 of the slab after width setting is less than the actual thickness h1 of the slab after width setting, the elevation position of the lower pinch roller 3 at the outlet will be set too high, and the slab 1 will cause a relatively serious impact on the lower pinch roller 3 at the outlet when passing through, causing problems such as damage to the roller surface of the lower pinch roller 3 at the outlet and shortened bearing service life. In addition, when the slab 1 passes through the outlet pinch roller, the calculated thickness H1 of the slab after width setting is less than the actual thickness h1 of the slab after width setting, and the slab 1 will not impact the outlet pinch roller, and the pressure of the upper pinch roller 4 at the outlet will not rise. At this time, the basic automation computer of the width setting machine cannot determine whether the slab 1 has bitten into the outlet pinch roller, and will not switch the upper pinch roller 4 at the outlet from position control to pressure control. In this way, due to the lack of the clamping force and conveying force of the outlet pinch roller, the slab 1 can easily slip in the width setting machine and stop moving forward. Summary of the invention

[0022] In view of the above-mentioned defects existing in the prior art, the present invention provides an exit pinch roller control method of a width sizing machine. In view of the problem of inaccurate calculated thickness of the slab after the width is sized, an actual position detection device of the slab is added at the exit of the width sizing machine, and the control mode of the pinch roller at the exit of the width sizing machine is changed, so as to achieve the purpose of reducing the slipping of the slab in the width sizing machine and the damage to the roller surface and mechanical equipment when the slab is fed into the steel.

[0023] To achieve the above object, the present invention adopts the following technical solution:

[0024] A method for controlling the outlet pinch roller of a width setting machine:

[0025] A slab actual position detection device is added behind the exit pinch roller of the width setting machine to detect whether the slab passes through the exit pinch roller, and the slab actual position detection device transmits the detection data to the basic automation computer of the width setting machine;

[0026] After confirming that the slab has passed through the upper and lower pinch rollers at the exit, the basic automation computer of the width sizing machine switches the upper and lower pinch rollers at the exit to pressure control at the same time, and the upper and lower pinch rollers at the exit search for the upper and lower surfaces of the slab;

[0027] When the pressure of the outlet lower pinch roller rises to the set pressure, the outlet lower pinch roller is switched to position control, and the outlet upper pinch roller maintains pressure control.

[0028] Preferably, the method for controlling the upper and lower pinch rollers at the outlet further includes the following process:

[0029] 1) The heating furnace draws steel, and the process machine sends the calculated thickness H of the slab before width setting and the calculated thickness H1 of the slab after width setting to the basic automation computer of the width setting machine;

[0030] 2) The basic automatic computer of the width setting machine calculates the elevation position EX LPR POS of the lower pinch roller at the outlet according to the calculated thickness H of the slab before width setting and the calculated thickness H1 of the slab after width setting;

[0031] 3) The basic automatic computer of the width setting machine calculates the roller gap EX PR GAP of the upper and lower pinch rollers at the outlet according to the calculated thickness H1 of the slab after width setting;

[0032] 4) When the head of the slab passes through the slab actual position detection device, the outlet pinch rollers are simultaneously switched to pressure control;

[0033] 5) When the pressure of the pinch roller on the outlet reaches the set pressure F, a delay time T is added, and the basic automation computer of the width setting machine records the position of the pinch roller on the outlet at this time, and maintains position control with this position as the target, and the pinch roller on the outlet still maintains pressure control with the set pressure F as the target;

[0034] 6) When the tail of the slab passes through the slab actual position detection device, the exit upper pinch roller is lifted up, and the exit lower pinch roller is set to the exit lower pinch roller elevation zero position EX LPR ZERO POS.

[0035] Preferably, in step 2), the elevation position EX LPR POS of the outlet lower pinch roller is calculated as follows:

[0036] EX LPR POS=EX LPR ZERO POS-(H1-H) / 2-b Formula 3;

[0037] In formula 3, EX LPR ZERO POS is the zero position of the lower pinch roller at the exit, H1 is the thickness of the slab after width setting, H is the thickness of the slab before width setting, and b is the additional value of the roller gap, which ranges from 5 mm to 15 mm.

[0038] Preferably, in step 3), the roller gap EX PR GAP of the outlet pinch roller is calculated as follows:

[0039] EX PR GAP=H1+b Formula 4;

[0040] In formula 4, H1 is the thickness of the slab after width is fixed, and b is the additional value of the roll gap, which ranges from 5 mm to 15 mm.

[0041] Preferably, in step 5), the set pressure F is in the range of 150KN to 250KN, and the delay time T is in the range of 1s to 20s.

[0042] Preferably, in step 6), the pinch roller on the outlet is raised to between 285 mm and 295 mm.

[0043] Preferably, the slab actual position detection device adopts DELTA DC2030 HMD hot metal detector.

[0044] The method for controlling the outlet pinch roller of a width-fixing machine provided by the present invention also has the following beneficial effects:

[0045] 1) It can effectively reduce the problem of slab slipping in the width setting machine caused by inaccurate theoretically calculated thickness of the slab after width setting, and reduce abnormal return of the slab;

[0046] 2) It can solve the problem that the elevation position of the lower pinch roller at the outlet is set too high, causing a serious impact on the lower pinch roller when the slab passes through, resulting in damage to the roller surface of the lower pinch roller at the outlet and shortening the service life of the bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is the working principle diagram of the existing width setting machine;

[0048] Figure 2 It is a schematic diagram of the entrance pinch rollers of the slab entering the width setting machine;

[0049] Figure 3 It is a schematic diagram of the exit pinch rollers of the slab entering the width setting machine;

[0050] Figure 4 It is a flow chart of the control method of the outlet pinch roller of the existing width setting machine;

[0051] Figure 5 It is a schematic diagram of adding a slab actual position detection device in the exit pinch roller control method of the width setting machine of the present invention;

[0052] Figure 6 It is a flow chart of the method for controlling the outlet pinch rollers of the width-fixing machine of the present invention. DETAILED DESCRIPTION

[0053] In order to better understand the above technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0054] Please combine Figure 5 As shown, the present invention provides a method for controlling the outlet pinch roller of a width-fixing machine:

[0055] A slab actual position detection device 8 is added behind the outlet pinch rollers of the width setting machine (the outlet pinch rollers include the outlet upper pinch rollers 5 and the outlet lower pinch rollers 6) to detect whether the slab 7 passes through the outlet pinch rollers. The slab actual position detection device 8 transmits the detection data to the basic automation computer of the width setting machine;

[0056] After confirming that the slab 7 has passed through the upper and lower pinch rollers 5 and 6 at the outlet, the basic automation computer of the width setting machine switches the upper and lower pinch rollers 5 and 6 at the outlet to pressure control at the same time, and the upper and lower pinch rollers 5 and 6 at the outlet search for the corresponding upper and lower surfaces on the slab 7;

[0057] When the pressure of the outlet lower pinch roller 6 rises to the set pressure F, the outlet lower pinch roller 6 is switched to position control, while the outlet upper pinch roller 5 continues to maintain pressure control.

[0058] Please combine Figure 6 As shown, the control method of the upper and lower pinch rollers at the outlet of the width setting machine of the present invention further includes the following process:

[0059] 1) The heating furnace draws steel, and the process machine sends the calculated thickness H of the slab before width setting and the calculated thickness H1 of the slab after width setting to the basic automation computer of the width setting machine;

[0060] 2) The basic automation computer of the width setting machine calculates the elevation position EX LPR POS of the lower pinch roller at the exit according to the calculated thickness H of the slab before width setting and the calculated thickness H1 of the slab after width setting in combination with formula 3;

[0061] EX LPR POS=EX LPR ZERO POS-(H1-H) / 2-b Formula 3;

[0062] In formula 3, EX LPR ZERO POS is the zero position of the lower pinch roller at the exit, H1 is the thickness of the slab after width setting, H is the thickness of the slab before width setting, and b is the additional value of the roller gap, which ranges from 5mm to 15mm.

[0063] 3) The basic automation computer of the width setting machine calculates the roller gap EX PR GAP of the upper and lower pinch rollers at the exit according to the calculated thickness H1 of the slab after width setting and in combination with formula 4. The roller gap of the upper and lower pinch rollers at the exit is the roller gap between the lower pinch roller 6 at the exit and the upper pinch roller 5 at the exit when the lower pinch roller 6 is at the elevation position;

[0064] EX PR GAP=H1+b Formula 4;

[0065] In formula 4, H1 is the thickness of the slab after width setting, and b is the additional value of the roll gap, which ranges from 5 mm to 15 mm;

[0066] 4) When the head of the slab 7 passes through the slab actual position detection device 8, the outlet pinch rollers are simultaneously switched to pressure control;

[0067] 5) When the pressure of the upper pinch roller 5 at the outlet reaches the set pressure F, the basic automation computer of the width setting machine records the position of the lower pinch roller 6 at the outlet at this time, and maintains position control with this position as the target. The upper pinch roller 5 at the outlet still maintains pressure control with the set pressure F as the target;

[0068] The value range of the set pressure F is between 150KN and 250KN, and the value range of the delay time T is between 1s and 20s;

[0069] 6) When the tail of the slab 7 passes through the slab actual position detection device 8, the exit upper pinch roller is lifted up by 290 mm, and the exit lower pinch roller 6 is set to the exit lower pinch roller elevation zero position EX LPR ZERO POS.

[0070] The slab actual position detection device 8 adopts a DELTA DC2030 HMD hot metal detector with a measurement range of 400°C to 1500°C.

[0071] Example 1

[0072] The calculated thickness of the slab before width setting is H=250mm, and the calculated thickness of the slab after width setting is H1=264mm, B=10mm, F=250KN, T=5s.

[0073] The flow of the method for controlling the outlet pinch roller of the width setting machine of the present invention is as follows:

[0074] 1) Start;

[0075] 2) The heating furnace draws steel, and the process machine sends the calculated thickness H=250mm before the slab is width-set and the calculated thickness H1=264mm after the slab is width-set to the basic automation computer of the width-setting machine;

[0076] 3) The basic automation computer of the width setting machine calculates the elevation position EX LPR POS of the lower pinch roller 6 at the outlet based on the calculated thickness H=250mm before the slab width setting and the calculated thickness H1=264mm after the slab width setting and in combination with Formula 3.

[0077] EX LPR POS=EX LPR ZERO POS-(H1-H) / 2-b Formula 3

[0078] =0-(264-250) / 2-10

[0079] =-17mm;

[0080] 4) The basic automation computer of the width setting machine calculates the roller gap EX PR GAP of the outlet pinch rollers according to the calculated thickness H1=264mm after the slab is width set and combined with formula 4. The roller gap of the outlet pinch rollers is the roller gap between the outlet upper and lower pinch rollers 5 and 6 when the outlet lower pinch roller 6 is at the elevation position;

[0081] EX PR GAP=H1+b Formula 4

[0082] =264+10

[0083] =274mm;

[0084] 5) When the head of the slab 7 passes through the slab actual position detection device 8, the outlet pinch rollers are simultaneously switched to pressure control;

[0085] 6) When the pressure of the upper pinch roller 5 at the outlet reaches the set pressure of 250kn, a delay of 5S is made, and the lower pinch roller 6 at the outlet records the position at this time, and maintains position control based on this position as the target, and the upper pinch roller 5 at the outlet still maintains pressure control with the set pressure of 250kn as the target;

[0086] 7) When the tail of the slab 7 passes through the slab actual position detection device 8, the upper pinch roller 5 at the exit is raised to 290 mm, and the lower pinch roller 6 at the exit is set to 0;

[0087] 8) End.

[0088] Example 2

[0089] The calculated thickness of the slab before width setting is H=241mm, and the calculated thickness of the slab after width setting is H1=252mm, B=10mm, F=250KN, T=5s.

[0090] The flow of the method for controlling the outlet pinch roller of the width setting machine of the present invention is as follows:

[0091] 1) Start;

[0092] 2) The heating furnace draws steel, and the process machine sends the calculated thickness H=241mm before the slab is width-set and the calculated thickness H1=252mm after the slab is width-set to the basic automation computer of the width-setting machine;

[0093] 3) The basic automation computer of the width setting machine calculates the elevation position EX LPR POS of the lower pinch roller 6 at the outlet based on the calculated thickness H=241 mm before the slab width setting and the calculated thickness H1=252 mm after the slab width setting and in combination with Formula 3.

[0094] EX LPR POS=EX LPR ZERO POS-(H1-H) / 2-b Formula 3

[0095] =0-(252-241) / 2-10

[0096] =-15.5mm;

[0097] 4) The basic automation computer of the width setting machine calculates the roller gap EX PR GAP of the outlet pinch rollers according to the calculated thickness H1=252mm of the slab after width setting and combines it with formula 4. The roller gap of the outlet pinch rollers is the roller gap between the outlet upper and lower pinch rollers 5 and 6 when the outlet lower pinch roller 6 is at the elevation position;

[0098] EX PR GAP=H1+b Formula 4

[0099] =252+10

[0100] =262mm;

[0101] 5) When the head of the slab 7 passes through the slab actual position detection device 8, the outlet pinch rollers are simultaneously switched to pressure control;

[0102] 6) When the pressure of the upper pinch roller 5 at the outlet reaches the set pressure of 250kn, a delay of 5S is made, and the lower pinch roller 6 at the outlet records the position at this time, and maintains position control based on this position as the target, and the upper pinch roller 5 at the outlet still maintains pressure control with the set pressure of 250kn as the target;

[0103] 7) When the tail of the slab 7 passes through the slab actual position detection device 8, the upper pinch roller 5 at the exit is raised to 290 mm, and the lower pinch roller 6 at the exit is set to 0;

[0104] 8) End.

[0105] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. As long as they are within the spirit of the present invention, any changes or modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. A method for controlling the outlet pinch roller of a width setting machine, characterized in that: A slab actual position detection device is added behind the exit pinch roller of the width setting machine to detect whether the slab passes through the exit pinch roller, and the slab actual position detection device transmits the detection data to the basic automation computer of the width setting machine; After confirming that the slab has passed through the upper and lower pinch rollers at the exit, the basic automation computer of the width sizing machine switches the upper and lower pinch rollers at the exit to pressure control at the same time, and the upper and lower pinch rollers at the exit search for the upper and lower surfaces of the slab; When the pressure of the outlet lower pinch roller rises to the set pressure, the outlet lower pinch roller is switched to position control, and the outlet upper pinch roller maintains pressure control. The method for controlling the upper and lower pinch rollers at the outlet further includes the following process: 1) The heating furnace draws steel, and the process machine sends the calculated thickness H of the slab before width setting and the calculated thickness H1 of the slab after width setting to the basic automation computer of the width setting machine; 2) The basic automatic computer of the width setting machine calculates the elevation position EX LPR POS of the lower pinch roller at the outlet according to the calculated thickness H of the slab before width setting and the calculated thickness H1 of the slab after width setting; 3) The basic automatic computer of the width setting machine calculates the roller gap EX PR GAP of the upper and lower pinch rollers at the outlet according to the calculated thickness H1 of the slab after width setting; 4) When the head of the slab passes through the slab actual position detection device, the upper and lower pinch rollers at the outlet are simultaneously switched to pressure control; 5) When the pressure of the pinch roller on the outlet reaches the set pressure F, a delay time T is added, and the basic automation computer of the width setting machine records the position of the pinch roller on the outlet at this time, and maintains position control with this position as the target, and the pinch roller on the outlet still maintains pressure control with the set pressure F as the target; 6) When the tail of the slab passes through the slab actual position detection device, the exit upper pinch roller is lifted up, and the exit lower pinch roller is set to the exit lower pinch roller elevation zero position EX LPR ZERO POS.

2. The method for controlling the outlet pinch roller of a width-fixing machine according to claim 1, characterized in that: In step 2), the elevation position EX LPR POS of the lower pinch roller at the outlet is calculated as follows: EX LPR POS=EX LPR ZERO POS-(H1-H) / 2-b Formula 3; In formula 3, EX LPR ZERO POS is the zero position of the lower pinch roller at the exit, H1 is the thickness of the slab after width setting, H is the thickness of the slab before width setting, and b is the additional value of the roller gap, which ranges from 5 mm to 15 mm.

3. The method for controlling the outlet pinch roller of a width-fixing machine according to claim 1, characterized in that: In step 3), the roller gap EX PR GAP of the outlet pinch roller is calculated as follows: EX PR GAP=H1+b Formula 4; In formula 4, H1 is the thickness of the slab after width is fixed, and b is the additional value of the roll gap, which ranges from 5 mm to 15 mm.

4. The method for controlling the outlet pinch roller of a width-fixing machine according to claim 1, characterized in that: In the step 5), the set pressure F is in the range of 150KN to 250KN, and the delay time T is in the range of 1s to 20s.

5. The method for controlling the outlet pinch roller of a width-fixing machine according to claim 1, characterized in that: In step 6), the outlet upper pinch roller is raised to between 285 mm and 295 mm.

6. The method for controlling the outlet pinch roller of a width-fixing machine according to claim 1, characterized in that: The slab actual position detection device adopts DELTA DC2030 HMD hot metal detector.

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