A method and system for checking the curvature of rough-rolled slabs

Abstract

The present application provides a method and system for checking the curvature of rough-rolled slabs, the method comprising: obtaining the entrance slab thickness of the vertical roller odd passes and the vertical roller side pressure of the corresponding odd passes; determining the target calibration data for the corresponding odd passes based on the entrance slab thickness and the vertical roller curvature calibration limit coefficient preset for the corresponding odd passes; if the target calibration data for any odd pass is less than the vertical roller side pressure of the corresponding odd pass, determining that the vertical roller curvature calibration for the corresponding odd pass is out of limit, and taking the corresponding odd pass as the target pass; reducing the vertical roller load of the target pass according to a preset ratio to recalculate the target calibration data of the target pass to determine if the vertical roller curvature is out of limit, until the vertical roller curvature calibration for the target pass is within the limit, then setting the vertical roller gap according to the vertical roller load parameter that is within the limit of the curvature calibration. The present application can avoid the recurrence of scrap steel pile accidents caused by unreasonable vertical roller gap settings.

Description

Technical Field

[0001] The present invention relates to the field of steel production and manufacturing, and in particular to a method and system for checking the curvature of a rough-rolled slab. Background Art

[0002] The function of the roughing mill of the hot rolling production line is to roll the slab sent from the heating furnace into an intermediate slab of a certain thickness and width to meet the requirements of the subsequent finishing rolling process. Vertical rollers are often arranged in front of the roughing mill to compress the width of the slab to achieve the purpose of controlling the width of the intermediate slab. This is also the main method of width control of the hot rolling production line at present. In the width control process of the existing control technology, the vertical roller gap is set and calculated according to the load distribution coefficient in the secondary process parameter table. Since the existing control system has no vertical roller slab curvature verification method, the slab is often clamped and arched in the 1st, 3rd, and 5th passes during the rough rolling process due to the small setting of the vertical roller gap. The slab that is clamped and curved cannot smoothly enter the flat roller rolling and piles up steel; at the same time, due to the small setting of the vertical roller gap, the slab width reduction is too large. During the rolling process, the vertical roller motor current is too large and the power is tripped, and the steel piling accident often occurs, which seriously affects the stable and smooth production. Summary of the Invention

[0003] In view of the above problems existing in the prior art, the present invention proposes a method and system for checking the curvature of rough-rolled slabs, which mainly solves the problems of low accuracy in setting the roll gap of the vertical rollers in the existing control technology, resulting in the incoming slabs being clamped and piled up, and the vertical roller width reduction being too large, resulting in motor tripping and piling up steel.

[0004] In order to achieve the above-mentioned and other purposes, the technical solutions adopted by the present invention are as follows.

[0005] The present application provides a method for checking the curvature of a rough-rolled slab, comprising:

[0006] Obtain the entrance slab thickness of the vertical roller at odd passes and the side pressure of the vertical roller at the corresponding odd passes;

[0007] Determine the target calibration data corresponding to the odd pass according to the inlet slab thickness of the odd pass and the vertical roller deflection calibration limit coefficient preset for the odd pass;

[0008] If the target calibration data of any odd pass is less than the vertical roller side pressure of the corresponding odd pass, it is determined that the vertical roller deflection calibration of the corresponding odd pass is out of limit, and the corresponding odd pass is used as the target pass;

[0009] The vertical roller load of the target pass is reduced according to a preset ratio to recalculate the target calibration data of the target pass to perform vertical roller deflection calibration over-limit judgment until the vertical roller deflection calibration of the target pass is within the limit. The vertical roller gap is then set according to the vertical roller load parameters of the target pass in which the deflection calibration is within the limit.

[0010] In one embodiment of the present application, obtaining the inlet slab thickness of the vertical roller at odd passes includes:

[0011] Obtain the outlet slab thickness of the vertical roller at odd passes and the relative reduction rate of the corresponding flat roller at odd passes;

[0012] The inlet slab thickness corresponding to the odd pass is determined according to the outlet slab thickness and the relative reduction rate.

[0013] In one embodiment of the present application, obtaining the side pressure of the vertical roller corresponding to the odd pass includes:

[0014] Obtain the incoming slab width and the target width of the rough rolling intermediate bar;

[0015] Determining the total width expansion of rough rolling according to the incoming slab width and the target width;

[0016] The side pressure of the vertical roll corresponding to the odd pass is determined according to the total width expansion of the rough rolling and the relative reduction rate preset for each odd pass of the vertical roll.

[0017] In one embodiment of the present application, before determining the target calibration data corresponding to the odd pass according to the inlet slab thickness of the odd pass and the vertical roller deflection calibration limit coefficient preset corresponding to the odd pass, the method includes:

[0018] A corresponding vertical roller deflection check limit coefficient is configured for each odd pass of the vertical roller as the vertical roller deflection check limit coefficient preset for the corresponding odd pass.

[0019] In one embodiment of the present application, the target calibration data of the target pass is recalculated to determine whether the vertical roller deflection calibration exceeds the limit, until the vertical roller deflection calibration of the target pass does not exceed the limit, further comprising:

[0020] If the number of times the target check data of the target pass is recalculated exceeds a preset number threshold and the vertical roller deflection check corresponding to the target pass is always out of limit, a warning message is output.

[0021] In one embodiment of the present application, the roll gap of the vertical roller is set according to the vertical roller load parameter that is within the limit of the scoop deflection check, including:

[0022] Obtaining the first entrance slab width of the vertical roller odd pass, the vertical roller rolling force, and the vertical roller mill stiffness as the vertical roller load parameters;

[0023] The roll gaps of the vertical rollers at the odd passes are determined according to the first inlet slab width, the vertical roller rolling force, the vertical roller mill rigidity and the vertical roller side pressure.

[0024] In one embodiment of the present application, the roll gap of the vertical roller is set according to the vertical roller load parameter that is within the limit of the bowl deflection check, and further includes:

[0025] Obtaining the second entrance slab width of the vertical roller even pass, the flat roller width spread, and the roll gap increase of the vertical roller even pass as the vertical roller load parameters;

[0026] The roll gap of the vertical rollers corresponding to the even pass is determined according to the width of the second inlet slab, the width expansion of the flat rollers and the roll gap increase of the vertical rollers in the even pass.

[0027] The present application also provides a rough rolling slab warp checking system, comprising:

[0028] A data acquisition module is used to obtain the slab thickness at the entrance of the vertical roller at odd passes and the side pressure of the vertical roller at the corresponding odd passes;

[0029] A roll deflection calibration calculation module is used to determine target calibration data corresponding to the odd pass according to the inlet slab thickness and the vertical roller deflection calibration limit coefficient preset for the corresponding odd pass;

[0030] A deflection exceeding limit judgment module is configured to determine that the deflection calibration of the vertical roller of the corresponding odd pass exceeds the limit if the target calibration data of any odd pass is less than the side pressure of the vertical roller of the corresponding odd pass, and use the corresponding odd pass as the target pass;

[0031] The load adjustment and roll gap setting module is used to reduce the vertical roller load of the target pass according to a preset ratio to recalculate the target calibration data of the target pass to perform vertical roller deflection calibration over-limit judgment until the vertical roller deflection calibration of the target pass is within the limit. The vertical roller gap is then set according to the vertical roller load parameters of the target pass in which the deflection calibration is within the limit.

[0032] As described above, the method and system for checking the curvature of rough-rolled slabs of the present invention have the following beneficial effects.

[0033] The present application can calculate whether the incoming slab curvature check exceeds the limit based on the slab thickness at the entrance of the odd pass of the vertical roller and the side pressure of the vertical roller in the odd pass, and automatically reduce the vertical roller load of the corresponding pass if the curvature check exceeds the limit, and then calculate the vertical roller gap setting when the curvature check of the corresponding pass does not exceed the limit. This can effectively avoid the repeated occurrence of accidents such as the slab being clamped and unable to smoothly enter the flat roller for rolling due to the vertical roller gap being set too small, and the repeated occurrence of accidents such as steel piling due to the vertical roller gap being set too small, the single-pass width reduction being too large, and the vertical roller motor current being too large and power off during width rolling. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a flow chart of a method for checking the curvature of a rough-rolled slab in one embodiment of the present application.

[0035] Figure 2 Module diagram of a rough-rolled slab curvature check system in one embodiment of the present application. DETAILED DESCRIPTION

[0036] The following describes the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. The details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other unless they conflict.

[0037] It should be noted that the illustrations provided in the following embodiments are merely schematic illustrations of the basic concept of the present invention. Therefore, the illustrations only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0038] See also Figure 1 The present invention provides a method for checking the curvature of a rough-rolled slab, the method comprising the following steps:

[0039] Step S100, obtaining the thickness of the slab at the entrance of the odd passes of the vertical rollers and the side pressure of the vertical rollers corresponding to the odd passes.

[0040] In one embodiment, the rough rolling can reduce the width of the incoming slab in odd passes by the vertical roller mill in front of the machine, and the vertical roller mill will pass through even passes. Specifically, taking the vertical roller mill rolling 5 passes as an example, the vertical rollers are reduced in width in passes 1, 3, and 5, and the vertical rollers are passed through passes 2 and 4. In order to solve the problem of low accuracy in setting the vertical roller gap, the incoming slab is clamped and warped and cannot smoothly enter the flat roller rolling, resulting in repeated steel pile accidents, the slab warping calculation can be performed when calculating the roll gap setting of each pass of the rough rolling vertical roller. If the warping check is within the limit, the vertical roller gap setting calculation of this pass is successful. If the warping check is beyond the limit, the vertical roller load parameter of this pass is automatically reduced, and the vertical roller load of the remaining passes is automatically increased, and then the warping check cycle calculation is performed again until the warping check of this pass is within the limit. Before performing the warping check calculation, the slab thickness at the entrance of the vertical rollers of the odd passes needs to be collected.

[0041] In one embodiment, obtaining the inlet slab thickness of the odd passes of the vertical rollers includes: obtaining the outlet slab thickness of the odd passes of the vertical rollers and the relative reduction rate of the flat rollers corresponding to the odd passes; and determining the inlet slab thickness of the corresponding odd passes based on the outlet slab thickness and the relative reduction rate.

[0042] Specifically, the calculation method of the entrance slab thickness of the vertical roller odd pass can be expressed as:

[0043] Hi=hi / (1-Ldi)

[0044] Wherein, i: number of passes (1, 3, 5 passes), Hi: thickness of slab at the entrance of each pass, when i=1, it is the incoming slab thickness, hi: thickness at the exit of each pass, Ldi: relative reduction rate of flat roller at each pass (can be pre-set through the process parameter table).

[0045] In one embodiment, obtaining the side pressure of the vertical roller corresponding to the odd passes includes: obtaining the width of the incoming slab and the target width of the rough rolling intermediate bar; determining the total width expansion of the rough rolling according to the incoming slab width and the target width; determining the side pressure of the vertical roller corresponding to the odd passes according to the total width expansion of the rough rolling and the relative reduction rate preset for each odd pass of the vertical roller.

[0046] Specifically, the calculation method of the total width expansion of rough rolling can be expressed as:

[0047] BR=B–BH

[0048] Among them, BR: total width expansion of rough rolling, B: incoming slab width, BH: target width of intermediate slab.

[0049] The calculation method of the side pressure of each pass vertical roller can be expressed as:

[0050] BE=BR×Li

[0051] Where BE is the side pressure of the vertical rolls in each pass, BR is the total width expansion in roughing, and Li is the relative reduction rate of the vertical rolls in each pass (load distribution coefficient, set value in the process parameter table). Conventional vertical roll load distribution coefficients are 0.2, 0.5, and 0.3, which are equivalent to 20%, 50%, and 30% of the total width reduction of the vertical rolls in the 1st, 3rd, and 5th passes, respectively. Specific rolling steel grades and specifications have different vertical roll load distribution coefficients.

[0052] Step S110 , determining target calibration data corresponding to the odd passes according to the inlet slab thickness and the vertical roller deflection calibration limit coefficient preset for the odd passes.

[0053] In one embodiment, before determining target calibration data corresponding to odd passes based on the inlet slab thickness and the preset vertical roller deflection calibration limit coefficient for the odd passes, the method includes: configuring a corresponding vertical roller deflection calibration limit coefficient for each odd pass as the preset vertical roller deflection calibration limit coefficient for the odd pass. Specifically, the vertical roller deflection calibration limit coefficient for one pass is 0.65, the vertical roller deflection calibration limit coefficient for three passes is 0.65, and the vertical roller deflection calibration limit coefficient for five passes is 0.45. The specific setting is adjusted based on actual on-site control conditions.

[0054] In one embodiment, the target calibration data may be expressed as the product of the vertical roller deflection calibration limit coefficient and the inlet slab thickness corresponding to the odd pass.

[0055] Step S120: If the target calibration data of any odd pass is less than the vertical roller side pressure of the corresponding odd pass, it is determined that the vertical roller deflection calibration of the corresponding odd pass is out of limit, and the corresponding odd pass is used as the target pass.

[0056] In one embodiment, the calculation method for checking the vertical roller deflection can be expressed as:

[0057] BE>Ki×Hi

[0058] Among them, BE: the side pressure of the vertical roller in each pass, Ki: the limit coefficient of the vertical roller deflection calibration, Hi: the inlet slab thickness of the vertical roller in each pass.

[0059] If the side pressure of the vertical roller in an odd pass is greater than the target calibration data of that pass, the vertical roller deflection calibration of that pass exceeds the limit.

[0060] Step S130, reducing the vertical roller load of the target pass according to a preset ratio to recalculate the target calibration data of the target pass to perform vertical roller deflection calibration over-limit judgment, until the vertical roller deflection calibration of the target pass is within the limit, and then setting the vertical roller gap according to the vertical roller load parameters that are within the limit of the deflection calibration.

[0061] In one embodiment, the preset ratio can be set to 1%, or the ratio can be set according to actual application requirements. Here, 1% is taken as an example. If the bending check exceeds the limit, the load of the vertical roller of this pass will be automatically reduced by 1%. After reducing the load by 1%, the bending check cycle calculation will be performed again until the bending check of this pass does not exceed the limit.

[0062] In one embodiment, the target calibration data of the target pass is recalculated to perform an over-limit judgment on the vertical roller deflection calibration until the vertical roller deflection calibration of the target pass is within the limit, and the method further includes: if the number of times the target calibration data of the target pass is recalculated exceeds a preset number threshold and the vertical roller deflection calibration of the corresponding target pass is always over-limit, a warning message is output.

[0063] Specifically, if the vertical roller deflection calibration exceeds the limit, the vertical roller load of that pass will be automatically reduced by 1%, and the vertical roller deflection calibration calculation will be performed again. The maximum number of cyclic calculations is 30 times. If the vertical roller deflection calibration of that pass still exceeds the limit after more than 30 cyclic calculations, the deflection calibration calculation of that pass will be exited and an alarm will be prompted. If the deflection calibration of that pass does not exceed the limit after the cyclic calculation, the reduced vertical roller load parameters will be used to perform the vertical roller gap setting calculation.

[0064] In one embodiment, the roll gap of the vertical roller is set according to the vertical roller load parameters that are not exceeded during the deflection calibration, including: obtaining the first entrance slab width of the vertical roller odd pass, the vertical roller rolling force and the vertical roller mill stiffness; determining the vertical roller gap corresponding to the odd pass according to the first entrance slab width, the vertical roller rolling force, the vertical roller mill stiffness and the vertical roller side pressure.

[0065] In one embodiment, the vertical roll gap setting calculation is performed based on the vertical roll load parameters that are not exceeded in the scoop bending calibration, and also includes: obtaining the second entrance slab width of the vertical roll even pass, the flat roll width spread, and the vertical roll gap increase of the even pass; and determining the vertical roll gap of each pass based on the second entrance slab width, the flat roll width spread, and the vertical roll gap increase of the even pass.

[0066] Specifically, odd passes (passes 1, 3, and 5):

[0067] E=(Ei–BE)-FE / ME

[0068] Where, E: roll gap of vertical roller, Ei: entrance width of odd-pass vertical roller, BE: side pressure, FE: rolling force of vertical roller, ME: rigidity of vertical roller mill;

[0069] Even passes (2nd, 4th):

[0070] E=Ei+BR1+EH

[0071] Wherein, E: gap between vertical rollers, Ei: inlet width of vertical rollers in even passes, BR1: width expansion of flat roller R1, EH: gap increase of vertical rollers in even passes.

[0072] Through the above application scheme, the problems that the existing control technology has no calculation method for checking the roll gap of the rough rolling vertical roller and cannot judge whether the load and roll gap settings of the odd-pass vertical roller are reasonable, and cannot judge whether the slab will be clamped and buckled during the width rolling process can be effectively solved; it effectively avoids the repeated occurrence of accidents in which the clamped and buckled slab cannot smoothly enter the flat roller for rolling and steel piles up; it effectively avoids the repeated occurrence of steel pile-up accidents caused by the vertical roller gap setting being too small, the single-pass width reduction being too large, and the vertical roller motor current being too large and the power outage.

[0073] See also Figure 2 This embodiment provides a rough slab curvature verification system for executing the rough slab curvature verification method described in the aforementioned method embodiment. Because the technical principles of the system embodiment are similar to those of the aforementioned method embodiment, the same technical details will not be repeated here.

[0074] In one embodiment, a rough rolling slab buckling calibration system includes: a data acquisition module 10, which is used to obtain the entrance slab thickness of the vertical roller odd pass and the vertical roller side pressure of the corresponding odd pass; a buckling calibration calculation module 11, which is used to determine the target calibration data of the corresponding odd pass based on the entrance slab thickness and the vertical roller buckling calibration limit coefficient preset for the corresponding odd pass; a buckling overlimit judgment module 12, which is used to determine that the vertical roller buckling calibration of the corresponding odd pass is overlimit if the target calibration data of any odd pass is less than the vertical roller side pressure of the corresponding odd pass, and use the corresponding odd pass as the target pass; a load adjustment and roll gap setting module 13, which is used to reduce the vertical roller load of the target pass according to a preset ratio to recalculate the target calibration data of the target pass to perform vertical roller buckling calibration overlimit judgment, until the vertical roller buckling calibration of the target pass is within the limit, and then the vertical roller gap is set according to the vertical roller load parameters of the target pass where the buckling calibration is within the limit.

[0075] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A method for checking the curvature of a rough-rolled slab, characterized in that: include: Obtain the entrance slab thickness of the vertical roller at odd passes and the side pressure of the vertical roller at the corresponding odd passes; Obtaining the inlet slab thickness of the vertical roller odd passes, including: obtaining the outlet slab thickness of the vertical roller odd passes and the relative reduction rate of the flat roll corresponding to the odd passes; determining the inlet slab thickness of the vertical roller corresponding to the odd passes according to the outlet slab thickness and the relative reduction rate; obtaining the side pressure of the vertical roller corresponding to the odd passes, including: obtaining the width of the incoming slab and the target width of the roughing intermediate bar; determining the total width expansion of roughing according to the width of the incoming slab and the target width; determining the side pressure of the vertical roller corresponding to the odd passes according to the total width expansion of roughing and the relative reduction rate preset for each odd pass of the vertical roller; Determining target calibration data corresponding to the odd passes according to the inlet slab thickness and the vertical roller deflection calibration limit coefficient preset for the odd passes; before determining the target calibration data corresponding to the odd passes according to the inlet slab thickness and the vertical roller deflection calibration limit coefficient preset for the odd passes, the method includes: respectively configuring a corresponding vertical roller deflection calibration limit coefficient for each odd pass of the vertical roller as the preset vertical roller deflection calibration limit coefficient for the odd passes; If the target calibration data of any odd pass is less than the vertical roller side pressure of the corresponding odd pass, it is determined that the vertical roller deflection calibration of the corresponding odd pass is out of limit, and the corresponding odd pass is used as the target pass; The vertical roller load of the target pass is reduced according to a preset ratio, and the target calibration data of the target pass is recalculated to perform vertical roller deflection calibration over-limit judgment, until the vertical roller deflection calibration of the target pass is within the limit, and then the vertical roller gap is set according to the vertical roller load parameters of the target pass whose deflection calibration is within the limit; the target calibration data of the target pass is recalculated to perform vertical roller deflection calibration over-limit judgment, until the vertical roller deflection calibration of the target pass is within the limit, and further comprising: if the number of times the target calibration data of the target pass is recalculated exceeds a preset number threshold and the vertical roller deflection calibration of the corresponding target pass is always beyond the limit, a warning message is output.

2. The method for checking the warp of rough-rolled slab according to claim 1, characterized in that: The vertical roller gap is set based on the vertical roller load parameters of the target pass that does not exceed the limit in the scoop deflection check, including: Obtaining the first entrance slab width of the vertical roller odd pass, the vertical roller rolling force, and the vertical roller mill stiffness as the vertical roller load parameters; The roll gaps of the vertical rollers at the odd passes are determined according to the first inlet slab width, the vertical roller rolling force, the vertical roller mill rigidity and the vertical roller side pressure.

3. The method for checking the warp of rough-rolled slab according to claim 1, characterized in that: The vertical roller gap is set based on the vertical roller load parameters of the target pass that does not exceed the limit in the bowl deflection check, and also includes: Obtaining the second entrance slab width of the slab at the vertical roller even pass, the flat roller width spread, and the roll gap increase at the vertical roller even pass as the vertical roller load parameters; The roll gap of the vertical rollers corresponding to the even pass is determined according to the width of the second inlet slab, the width expansion of the flat rollers and the roll gap increase of the vertical rollers in the even pass.

4. A roughing slab warp checking system for executing the roughing slab warp checking method according to any one of claims 1 to 3, characterized in that: include: The data acquisition module is used to obtain the inlet slab thickness of the vertical roller at odd passes and the side pressure of the vertical roller at the corresponding odd passes; A roll deflection calibration calculation module is used to determine target calibration data corresponding to the odd pass according to the inlet slab thickness and the vertical roller deflection calibration limit coefficient preset for the corresponding odd pass; A deflection exceeding limit judgment module is configured to determine that the deflection calibration of the vertical roller of the corresponding odd pass exceeds the limit if the target calibration data of any odd pass is less than the side pressure of the vertical roller of the corresponding odd pass, and use the corresponding odd pass as the target pass; The load adjustment and roll gap setting module is used to reduce the vertical roller load of the target pass according to a preset ratio to recalculate the target calibration data of the target pass to perform vertical roller deflection calibration over-limit judgment until the vertical roller deflection calibration of the target pass is within the limit. The vertical roller gap is then set according to the vertical roller load parameters of the target pass for which the deflection calibration is within the limit.

Images