A non-contact method for straightening steel structure profiles

Abstract

This invention relates to a non-contact method for straightening the straightness of steel structure profiles, comprising a non-contact testing device. The testing method includes the following steps: S1. Measuring the surface dimensions of the steel structure profile along its length before straightening; S2. Determining the measurement point of the moving laser displacement sensor in the laser sensor positioning assembly during the measurement process; S3. Measuring the surface dimensions near the bottom and top of the profile along its height direction using both the moving and fixed laser displacement sensors; S4. Judging the straightness and perpendicularity of the steel structure profile based on the data obtained in S1 to S3; S5. Adjusting the working parameters of the straightening press according to the judgment data obtained in step S4, and performing pressure straightening on the steel structure profile; S6. Re-inspecting the straightness parameters of the straightened steel structure profile. This invention automates the inspection and straightening process of steel structure profiles, improving the inspection efficiency and product quality of the straightening process.

Description

Technical Field

[0001] This invention relates to the field of steel structure production and processing equipment and technology, and in particular to a non-contact method for detecting the straightness of steel structure profiles during the straightening process. Background Technology

[0002] Steel structure buildings, as one of the main building structure types in modern industry, are mainly composed of various types of steel profiles and steel plates. Due to their simple construction and light weight, they are widely used in stadiums, large factories, and high-rise buildings. Therefore, the dimensions and shape quality of the steel profiles before structural assembly directly determine the construction safety of steel structure buildings.

[0003] Long profiles with different cross-sectional shapes are important materials for steel structure buildings. Due to residual stress changes caused by temperature variations during the initial processing and heat treatment, the original straightness and other geometric information of the steel structure are altered. Furthermore, unavoidable collisions during transportation and storage can cause various degrees of bending deformation in long steel profiles. When the geometric deformation exceeds a certain range, the next stage of product processing becomes impossible, resulting in scrap and significant economic losses for the company. Therefore, implementing methods such as straightening steel profiles is a crucial step before processing steel structure components. Currently, the straightening of long steel profiles in China mainly consists of two parts: pre- and post-straightening inspection and press bending. Pre- and post-straightening inspection primarily focuses on the straightness of the steel profiles. At present, the industry mainly uses manual string lines and visual inspection to check the straightness of steel structures. After obtaining the inspection data, construction workers set the pressure parameters of the pressure straightening machine based on experience. Profiles that fail the straightness measurement are then subjected to a press bending process. When the bending amount equals the springback amount, the bent part of the workpiece straightens after the pressure head is withdrawn.

[0004] The traditional steel structure profile straightening process described above has revealed various problems during implementation. Firstly, when manually checking the straightness of steel structures using string lines and visual inspection, factors such as the observation angle, observer fatigue, and the heat and light in the production workshop can all affect the visual inspection method, leading to significant errors and severely impacting subsequent production, thus reducing product yield. Secondly, with the continuous expansion of the application market for steel structure profiles, relying on manual straightness inspection will severely restrict production efficiency. Finally, during press bending, the straightness data measured manually is not accurate enough, and the bending amount set based on experience is difficult to accurately match the repair amount of the workpiece, requiring repeated measurements and bending processes, further restricting the straightening efficiency of steel structure profiles. To address these problems, it is necessary to design a non-contact detection device and method for the straightening process of steel structure profiles to improve the detection efficiency and product quality of the straightening process. Summary of the Invention

[0005] The purpose of this invention is to address the above-mentioned issues by providing a non-contact method for detecting the straightness of steel structure profiles during the straightening process. This invention automates the detection and straightening of steel structure profiles during the straightening process, thereby improving the detection efficiency and product quality of the steel structure profile straightening process.

[0006] The specific solution of this invention is: a non-contact detection method for the straightness of steel structure profiles in a straightening process, comprising a non-contact detection device, the non-contact detection device including a straightening press, a profile transmission mechanism arranged on the inlet and outlet sides of the straightening press, two sets of laser sensor positioning assemblies arranged on the sides of the travel path of the profile transmission mechanism on the inlet and outlet sides of the straightening press, an industrial control computer, a PLC system, a data converter, a data communication line, a storage system, and a power supply system, wherein the laser sensor positioning assembly includes a fixed mounting base, a fixed laser displacement sensor, a movable laser displacement sensor, a ball screw, a servo motor, and a coupling, the movable laser displacement sensor being driven to move up and down by the ball screw, and the detection method including the following steps:

[0007] S1. Measure the surface dimensions of the steel structure profile along its length before straightening: The steel structure profile is conveyed along the profile transmission mechanism on the inlet side of the straightening press. During the process, the laser sensor positioning component moves relative to the steel structure profile to realize the measurement of the surface dimensions along the entire length of the profile.

[0008] S2. During the measurement process, determine the measurement point of the moving laser displacement sensor in the laser sensor positioning assembly. The specific steps are as follows:

[0009] a) At the start of the test, the moving laser displacement sensor is zeroed and located at the lowest position of the ball screw;

[0010] b) The mobile laser displacement sensor in the laser sensor positioning assembly starts to send a measurement signal and receive the reflected signal. At the same time, the servo motor drives the ball screw to rotate at a low speed, which drives the mobile laser displacement sensor to move upward. The measurement data is collected through the data line and further transmitted to the industrial control computer for processing. The industrial control computer judges the data.

[0011] c) When the adjacent sets of data do not change, the servo motor speed remains constant, driving the moving laser displacement sensor to move upward;

[0012] d) When several adjacent sets of data change drastically, it indicates that the moving laser displacement sensor has moved to the top of the profile and exceeded the height range. At this time, the industrial control computer sends a command to the PLC to first stop the servo motor, and then control the servo motor to rotate in the opposite direction, driving the moving laser displacement sensor to move down a small distance. The distance moved is determined based on the detected displacement signal. That is, when the displacement measurement data of the moving laser displacement sensor is close to the data that has hardly changed before, ensure that the measurement point of the moving laser displacement sensor is outside the chamfer or rounded corner of the steel structure. Stop the servo motor and determine this as the displacement measurement point of the moving laser displacement sensor.

[0013] S3. Surface measurements near the bottom and top of the profile are achieved by using both a moving laser displacement sensor and a fixed laser displacement sensor;

[0014] S4. Based on the data obtained from measurements in S1 to S3, determine the straightness and perpendicularity of the steel structure profiles, and set the straightening working parameters of the straightening press accordingly, as follows:

[0015] a) Define the length parameter L of the steel structure profile, the straightness accuracy error requirement δ0, and the perpendicularity accuracy error requirement α0. At the same time, determine the number of displacement measurement values ​​within the stroke L range as n according to the measurement accuracy requirements.

[0016] b) The mobile laser displacement sensor and the fixed laser displacement sensor in the measurement system perform measurement work simultaneously;

[0017] c) The displacement data measured by the moving laser displacement sensor are U1, U2, U3, ... U n The fixed laser displacement sensor measures the corresponding displacement data as D1, D2, D3, ... D n ;

[0018] d) After the above measurement data is acquired by the PLC and transmitted to the host industrial control computer, the industrial control computer processes the data, judges the verticality, and if the verticality needs to be processed by the pressure straightening machine, the pressure straightening machine and the profile conveying mechanism coordinate their conveying speeds to carry out the straightening work in the height direction of the profile.

[0019] e) After the above measurement data is acquired by the PLC and transmitted to the host industrial control computer, the industrial control computer processes the data, judges the straightness, and sets the straightening force at the corresponding position for the profile that needs to be straightened.

[0020] S5. Adjust the working parameters of the straightening press according to the judgment data obtained by the straightening press in step S4, start the straightening press and perform pressure straightening operation on the steel structure profile;

[0021] S6. The straightened steel structure profiles undergo a straightness parameter re-inspection. This re-inspection is carried out through the laser sensor positioning component on the outlet side of the straightening press. The re-inspection steps are carried out according to steps S1 to S4. If the inspection results show that the straightening is unqualified, the industrial control computer will issue an instruction to the conveying system to transport the unqualified steel structure profiles back to the inlet side of the straightening press for straightening.

[0022] Furthermore, in this invention, one set of laser sensor positioning components is arranged on the inlet side of the straightening press, and the other set of laser sensor positioning components is arranged on the outlet side of the straightening press. The profile transmission mechanism consists of a conveyor belt or a conveyor roller.

[0023] Furthermore, the laser sensor positioning assembly of the present invention includes a fixed mounting base, a fixed laser displacement sensor, a movable laser displacement sensor, a ball screw, a servo motor, and a coupling. The fixed mounting base is disposed on the side of the profile transmission mechanism. The ball screw is vertically mounted on the fixed mounting base. The servo motor is mounted on the top of the fixed mounting base and is connected to the ball screw via the coupling. The fixed laser displacement sensor is disposed on the lower side of the fixed mounting base. The movable laser displacement sensor is mounted on the ball screw via a ball screw nut seat and moves up and down under the drive of the ball screw. The movable laser displacement sensor is located directly above the fixed laser displacement sensor.

[0024] Furthermore, in step S4 of this invention, the industrial control computer processes the data, and the specific method for determining the verticality is as follows:

[0025] i) Calculate the data as U1, U2, U3, ... U respectively. n And the data are D1, D2, D3, ... D n The differences for the same index are C1 = U1 - D1, C2 = U2 - D2, ... C n =U n -D n The vertical direction errors C1, C2, ... C at n measurement points are obtained. n ;

[0026] ii) C1, C2, ... C n Compare the absolute value with the perpendicularity accuracy error requirement α0. If C1, C2, ... C n If the absolute values ​​are all less than α0, it indicates that the profile verticality meets the requirements and there is no need to use a press for verticality straightening.

[0027] iii) If there exist C1, C2, ... C nIf the absolute value is greater than α0, it indicates that the profile's perpendicularity does not meet the requirements and a press is needed for perpendicularity straightening. This applies to profiles C1, C2, ..., C. n Points with an absolute value greater than α0 are recorded;

[0028] iv) For cases where verticality requires a straightening press, the straightening press is coordinated with the conveying speed of the profile transport mechanism to record C1, C2, ... C n For points with an absolute value greater than α0, targeted straightening work is carried out in the height direction of the profile in the area before and after them. The specific method is as follows: if the data C of the corresponding point... n If the sign is greater than zero, the straightening press applies a force pointing in the direction of the sensor installation on the upper section of the corresponding position on the profile. If the data C at the corresponding point... n If the sign is less than zero, the straightening press applies a force to the upper section of the profile at the corresponding position, pointing in the opposite direction to the sensor installation direction. The magnitude of the force is determined by C. n The magnitude of the difference between the absolute value and α0 is determined.

[0029] Furthermore, in step S4 of this invention, the industrial control computer processes the data, and the method for judging straightness is as follows:

[0030] i) Calculate the data as U1, U2, U3, ... U respectively. n And the data are D1, D2, D3, ... D n The average values ​​of the same subscript are A1=(U1+D1) / 2, A2=(U2+D2) / 2, ... A n =(U n +D n ) / 2, to obtain the average displacement measurement data A1, A2, ... A at n measurement points. n ;

[0031] ii) Find A1, A2, A3...A n The maximum value A in the series of data max and minimum value A min Calculate the absolute value Δ1 of the difference between the two;

[0032] iii) By comparing Δ1 with the known straightness standard δ0 that can be used for the corresponding profile, if Δ1 is less than δ0, the straightness of the current profile is qualified; if Δ1 is greater than δ0, the straightness of the current profile is unqualified and pressure straightening is required.

[0033] iv) For profiles requiring straightness correction, first define the reference distance A0 from the measured surface of the steel structure profile to the sensor. Then, use an industrial control computer to measure the data A1, A2, A2, ... A. nThe differences from the reference distance A0 are δ1, δ2, δ3, ... δ n ;

[0034] v) By plotting the corresponding coordinate curves and δ1, δ2, δ3, ... δ n The sign of δ is determined by the following formula: if δ1, δ2, δ3, ..., δ n A negative sign or a value below the coordinate point indicates that the straightening press needs to straighten the steel structure profile towards the laser sensor at that point. If δ1, δ2, δ3, ... δ n If the sign is positive or the value is above the coordinate point, it indicates that the straightening press needs to straighten the steel structure profile towards the side closer to the laser sensor at that point. The straightening force setting for the corresponding position can be based on δ1, δ2, δ3, ... δ n The absolute value is automatically adjusted.

[0035] This invention designs a non-contact method for straightening the straightness of steel structure profiles, which effectively automates the inspection and straightening process of steel structure profiles, improves the inspection efficiency of the straightening process, and thus enhances the product quality of steel structure profiles. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the non-contact detection device in this invention;

[0037] Figure 2 This is a schematic diagram of the laser sensor positioning component structure in this invention;

[0038] Figure 3 This is a straightness deviation coordinate curve diagram in an embodiment of the present invention.

[0039] In the diagram: 1—I-beam profile, 11—initial inspection profile, 12—re-inspection profile, 2—straightening press, 4—laser sensor positioning assembly, 41—servo motor, 42—coupling, 43—screw roller, 44—fixed mounting base, 45—ball screw nut seat, 461—moving laser displacement sensor, 462—fixed laser displacement sensor, 463—moving laser displacement sensor in the starting position, 47—mounting base, 5—stand, 6—profile transmission mechanism. Detailed Implementation

[0040] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0041] See Figure 1 , Figure 2 This is a schematic diagram of the non-contact detection device and the laser sensor positioning component in this invention; wherein the non-contact detection device includes: a primary inspection profile 11, a secondary inspection profile 12, a straightening press 2, a laser sensor positioning component 4, a stand 5, a profile transmission mechanism 6, and a control part not shown in the figure, including an industrial control computer, a PLC system, a data converter, a data communication line, a storage system, and a power supply system.

[0042] Figure 2 This is a structural diagram of the laser sensor positioning assembly, a key component in this invention. It includes: a fixed mounting base 44, a fixed laser displacement sensor 462 and its mounting base 47, a movable laser displacement sensor 461, a ball screw nut seat 45, a ball screw 43, a servo motor 41, a coupling 42, a movable laser displacement sensor 463 in the starting position, an I-beam profile 1, and a profile transmission mechanism 6.

[0043] The following is based on Figure 2 The I-beam profile is described as a specific implementation method.

[0044] The laser sensor positioning component 4 is installed at the middle position during the process of conveying the initial inspection profile 11 by the profile transmission mechanism 6, such as... Figure 1 As shown. During the conveying of the initial inspection profile 11, the laser sensor positioning component 4 and the platform 51 in the profile conveying mechanism remain stationary, while the initial inspection profile 11 remains in the direction of the straightening press 2. During this process, the laser sensor positioning component 4 and the initial inspection profile 11 form a relative motion, so that the fixed laser displacement sensor 462 can complete the surface dimension measurement of the entire length direction of the I-beam initial inspection profile 11.

[0045] The movable laser displacement sensor 461 and the ball screw nut seat 45 move up and down along the ball screw 43. During the straightening process, the measurement point of the movable laser displacement sensor 461 can be adjusted according to the dimensions of the I-beam profile. The specific process is as follows:

[0046] a) At the start of the detection, the moving laser displacement sensor 461 is zeroed out and positioned at the lowest point of the ball screw 43, such as... Figure 2 The moving laser displacement sensor 463, formed by the dashed lines in the middle, is in the starting position;

[0047] b) The position of the measuring point of the movable laser displacement sensor 463, which is in its initial position, is adjusted. The movable laser displacement sensor emits a measurement signal and receives the reflected signal. At the same time, the servo motor 41 drives the ball screw 43 to rotate at a low speed. The ball screw nut seat 45 mounted on the ball screw 43 drives the movable laser displacement sensor to move upward. The measurement data is collected through a data cable and transmitted to the PLC system for further processing by the industrial control computer. The industrial control computer then makes judgments on the data.

[0048] c) When the adjacent sets of data do not change, the servo motor 41 remains at a constant speed, driving the moving laser displacement sensor to continue moving upward.

[0049] d) When several adjacent sets of data change drastically, it indicates that the moving laser displacement sensor has moved to the top of the profile, exceeding the middle dimension of the I-beam profile. At this point, the industrial control computer sends a command to the PLC system, first controlling the servo motor 41 to stop, then controlling the servo motor 41 to rotate in the opposite direction, causing the moving laser displacement sensor to move downwards a short distance. The distance moved is determined based on the detected displacement signal. That is, when the displacement measurement data of the moving laser displacement sensor is close to the previously almost unchanged data, ensuring that the measurement point of the moving laser displacement sensor is outside the chamfer or fillet dimension of the steel structure, the servo motor stops, and this point is determined as the displacement measurement point of the moving laser displacement sensor. Figure 2 The position of the China Mobile laser displacement sensor 461.

[0050] In the above process, the industrial control computer processes the data, and the specific method for judging verticality is as follows:

[0051] i) Calculate the data as U1, U2, U3, ... U respectively. n And the data are D1, D2, D3, ... D n The differences for the same index are C1 = U1 - D1, C2 = U2 - D2, ... C n =U n -D n The vertical direction errors C1, C2, ... C at n measurement points are obtained. n ;

[0052] ii) C1, C2, ... C n Compare the absolute value with the perpendicularity accuracy error requirement α0. If C1, C2, ... C n If the absolute values ​​are all less than α0, it indicates that the profile verticality meets the requirements and there is no need to use a press for verticality straightening.

[0053] iii) If there exist C1, C2, ... C nIf the absolute value is greater than α0, it indicates that the profile's perpendicularity does not meet the requirements and a press is needed for perpendicularity straightening. This applies to profiles C1, C2, ..., C. n Points with an absolute value greater than α0 are recorded;

[0054] iv) For cases where verticality requires a straightening press, the straightening press is coordinated with the conveying speed of the profile transport mechanism to record C1, C2, ... C n For points with an absolute value greater than α0, targeted straightening work is carried out in the height direction of the profile in the area before and after them. The specific method is as follows: if the data C of the corresponding point... n If the sign is greater than zero, the straightening press applies a force pointing in the direction of the sensor installation on the upper section of the corresponding position on the profile. If the data C at the corresponding point... n If the sign is less than zero, the straightening press applies a force to the upper section of the profile at the corresponding position, pointing in the opposite direction to the sensor installation direction. The magnitude of the force is determined by C. n The magnitude of the difference between the absolute value and α0 is determined.

[0055] The industrial control computer processes the data, and the specific method for judging straightness is as follows:

[0056] i) Calculate the data as U1, U2, U3, ... U respectively. n And the data are D1, D2, D3, ... D n The average values ​​of the same subscript are A1=(U1+D1) / 2, A2=(U2+D2) / 2, ... A n =(U n +D n ) / 2, to obtain the average displacement measurement data A1, A2, ... A at n measurement points. n .

[0057] ii) Find A1, A2, A3...A n The maximum value A in the series of data max and minimum value A min Calculate the absolute value Δ1 of the difference between the two;

[0058] iii) By comparing Δ1 with the known straightness standard δ0 that can be used for the corresponding profile, if Δ1 is less than δ0, the straightness of the current profile is qualified; if Δ1 is greater than δ0, the straightness of the current profile is unqualified and pressure straightening is required.

[0059] iv) For profiles requiring straightness correction, first define the reference distance A0 from the measured surface of the steel structure profile to the sensor. Then, use an industrial control computer to measure the data A1, A2, A2, ... A. n The differences from the reference distance A0 are δ1, δ2, δ3, ... δn ;

[0060] v) By plotting the corresponding coordinate curves and δ1, δ2, δ3, ... δ n The sign of δ is determined by the following formula: if δ1, δ2, δ3, ..., δ n A negative sign or a value below the coordinate point indicates that the straightening press needs to straighten the steel structure profile towards the laser sensor at that point. If δ1, δ2, δ3, ... δ n If the sign is positive or the value is above the coordinate point, it indicates that the straightening press needs to straighten the steel structure profile towards the side closer to the laser sensor at that point. The straightening force setting for the corresponding position can be based on δ1, δ2, δ3, ... δ n The absolute value is automatically adjusted.

[0061] The surface data measurement of the I-beam profile will now begin.

[0062] The I-beam profile measured in this study is 8m long and 100mm high. The straightness accuracy error requirement is ±3mm / 10m, so the straightness accuracy error δ0 = 2.4mm. The perpendicularity accuracy error requirement is within 89.5°, so the perpendicularity accuracy error α0 = 0.87mm. At the same time, based on the required measurement accuracy, the number of displacement measurements within the 8m length range is determined to be 9. The distance between the laser measurement sensor and the profile surface is A0 = 450mm.

[0063] Implementation Case 1

[0064] Assume the data obtained by the sensor is as follows:

[0065]

[0066] The data obtained from the sensor measurement is as follows:

[0067]

[0068] Perform verticality calculations to obtain

[0069]

[0070] By comparing C1, C2, ... C9 with α0 = 0.87 mm, it was found that all of them were less than α0, and the perpendicularity of Example 1 met the requirements.

[0071] Straightness calculation yields...

[0072]

[0073] Where A max = A5=451.5mm, minimum value Amin = A9=449.85mm, the difference Δ1=1.65mm<δ0, the straightness of Example 1 also meets the requirements.

[0074] Implementation Case 2

[0075] Assume the data obtained by the sensor is as follows:

[0076]

[0077] The data obtained from the sensor measurement is as follows:

[0078]

[0079] Perform verticality calculations to obtain

[0080]

[0081] By comparing the absolute values ​​of C1, C2, ... C9 with α0 = 0.87 mm, it was found that the absolute values ​​at C1 and C6 are greater than α0. Therefore, the perpendicularity of Example 2 does not meet the requirements and straightening treatment is required.

[0082] Data C1, C2, ... C9 are transmitted to the straightening press. By judgment, it can be known that in the profile position segment corresponding to the initial C1, a force opposite to the direction of the laser sensor installation position is applied to the upper region of the I-beam profile; it can also be known that in the profile position segment corresponding to the initial C6, a force in the same direction as the laser sensor installation position is applied to the upper region of the I-beam profile.

[0083] Perform straightness calculations to obtain

[0084]

[0085] Where A max = A5=451.5mm, minimum value A min = A1=448.65mm, difference Δ1=2.85mm>δ0, the straightness of Example 2 does not meet the requirements and straightness correction needs to be carried out.

[0086] Calculate the differences between straightness deviations A1, A2, ... A9 and A0, and obtain...

[0087]

[0088] The resulting coordinate curve is as follows Figure 3As shown, if δ1, δ2, and δ9 are negative or their values ​​are below the coordinate points, it indicates that the straightening press needs to straighten the steel structure profile towards the laser sensor at that point. If δ3, δ4, δ5, δ6, δ7, and δ8 are positive or their values ​​are above the coordinate points, it indicates that the straightening press needs to straighten the steel structure profile towards the laser sensor at that point. The straightening force setting at the corresponding position can be automatically adjusted based on the absolute values ​​of δ1, δ2, δ3, ..., δ9.

Claims

1. A non-contact method for detecting the straightness of steel structure profiles during straightening, comprising a non-contact detection device, the non-contact detection device comprising a straightening press, a profile transmission mechanism arranged on the inlet and outlet sides of the straightening press, two sets of laser sensor positioning assemblies arranged on the sides of the travel path of the profile transmission mechanism on the inlet and outlet sides of the straightening press, an industrial control computer, a PLC system, a data converter, a data communication line, a storage system, and a power supply system, wherein the laser sensor positioning assembly comprises a fixed mounting base, a fixed laser displacement sensor, a movable laser displacement sensor, a ball screw, a servo motor, and a coupling, the movable laser displacement sensor being driven to move up and down by the ball screw, characterized in that... The detection method includes the following steps: S1. Measure the surface dimensions of the steel structure profile along its length before straightening: The steel structure profile is conveyed along the profile transmission mechanism on the inlet side of the straightening press. During the process, the laser sensor positioning component moves relative to the steel structure profile to realize the measurement of the surface dimensions along the entire length of the profile. S2. During the measurement process, determine the measurement point of the moving laser displacement sensor in the laser sensor positioning assembly. The specific steps are as follows: a) At the start of the test, the moving laser displacement sensor is zeroed and located at the lowest position of the ball screw; b) The mobile laser displacement sensor in the laser sensor positioning assembly starts to send a measurement signal and receive the reflected signal. At the same time, the servo motor drives the ball screw to rotate at a low speed, which drives the mobile laser displacement sensor to move upward. The measurement data is collected through the data line and further transmitted to the industrial control computer for processing. The industrial control computer judges the data. c) When the adjacent sets of data do not change, the servo motor speed remains constant, driving the moving laser displacement sensor to move upward; d) When several adjacent sets of data change drastically, it indicates that the moving laser displacement sensor has moved to the top of the profile and exceeded the height range. At this time, the industrial control computer sends a command to the PLC to first stop the servo motor, and then control the servo motor to rotate in the opposite direction, driving the moving laser displacement sensor to move down a small distance. The distance moved is determined based on the detected displacement signal. That is, when the displacement measurement data of the moving laser displacement sensor is close to the data that has hardly changed before, ensure that the measurement point of the moving laser displacement sensor is outside the chamfer or rounded corner of the steel structure. Stop the servo motor and determine this as the displacement measurement point of the moving laser displacement sensor. S3. Surface measurements near the bottom and top of the profile are achieved by using both a moving laser displacement sensor and a fixed laser displacement sensor; S4. Based on the data obtained from measurements in S1 to S3, determine the straightness and perpendicularity of the steel structure profiles, and set the straightening working parameters of the straightening press accordingly, as follows: a) Define the length parameter L of the steel structure profile, the straightness accuracy error requirement δ0, and the perpendicularity accuracy error requirement α0. At the same time, determine the number of displacement measurement values ​​within the stroke L range as n according to the measurement accuracy requirements. b) The mobile laser displacement sensor and the fixed laser displacement sensor in the measurement system perform measurement work simultaneously; c) the mobile laser displacement sensor measures corresponding displacement data U1, U2, U3, …… U n , and the fixed laser displacement sensor measures corresponding displacement data D1, D2, D3, …… D n ; d) After the above measurement data is acquired by the PLC and transmitted to the host industrial control computer, the industrial control computer processes the data, judges the verticality, and if the verticality needs to be processed by the pressure straightening machine, the pressure straightening machine and the profile conveying mechanism coordinate their conveying speeds to carry out the straightening work in the height direction of the profile. e) After the above measurement data is acquired by the PLC and transmitted to the host industrial control computer, the industrial control computer processes the data, judges the straightness, and sets the straightening force at the corresponding position for the profile that needs to be straightened. S5. Adjust the working parameters of the straightening press according to the judgment data obtained by the straightening press in step S4, start the straightening press and perform pressure straightening operation on the steel structure profile; S6. The straightened steel structure profiles undergo a straightness parameter re-inspection. This re-inspection is carried out through the laser sensor positioning component on the outlet side of the straightening press. The re-inspection steps are carried out according to steps S1 to S4. If the inspection results show that the straightening is unqualified, the industrial control computer will issue an instruction to the conveying system to transport the unqualified steel structure profiles back to the inlet side of the straightening press for straightening.

2. The non-contact method for detecting the straightness of steel structure profiles during straightening as described in claim 1, characterized in that, One set of laser sensor positioning components is arranged on the inlet side of the straightening press, and the other set of laser sensor positioning components is arranged on the outlet side of the straightening press. The profile transmission mechanism consists of a conveyor belt or a conveyor roller.

3. The non-contact method for detecting the straightness of steel structure profiles during straightening process according to claim 1, characterized in that, The laser sensor positioning assembly includes a fixed mounting base, a fixed laser displacement sensor, a movable laser displacement sensor, a ball screw, a servo motor, and a coupling. The fixed mounting base is located on the side of the profile transmission mechanism. The ball screw is vertically mounted on the fixed mounting base. The servo motor is mounted on the top of the fixed mounting base and is connected to the ball screw via the coupling. The fixed laser displacement sensor is located on the lower side of the fixed mounting base. The movable laser displacement sensor is mounted on the ball screw via a ball screw nut seat and moves up and down under the drive of the ball screw. The movable laser displacement sensor is located directly above the fixed laser displacement sensor.

4. The non-contact method for detecting the straightness of steel structure profiles during straightening process according to claim 1, characterized in that, In step S4, the industrial control computer processes the data, and the specific method for determining verticality is as follows: i) Calculate the data as U1, U2, U3, ... U respectively. n And the data are D1, D2, D3, ... D n The differences for the same index are C1 = U1 - D1, C2 = U2 - D2, ... C n =U n -D n The vertical direction errors C1, C2, ... C at n measurement points are obtained. n ; ii) C1, C2, ... C n Compare the absolute value with the perpendicularity accuracy error requirement α0. If C1, C2, ... C n If the absolute values ​​are all less than α0, it indicates that the profile verticality meets the requirements and there is no need to use a press for verticality straightening. iii) If there exist C1, C2, ... C n If the absolute value is greater than α0, it indicates that the profile's perpendicularity does not meet the requirements and a press is needed for perpendicularity straightening. This applies to profiles C1, C2, ..., C. n Points with an absolute value greater than α0 are recorded; iv) For cases where verticality requires a straightening press, the straightening press is coordinated with the conveying speed of the profile transport mechanism to record C1, C2, ... C n For points with an absolute value greater than α0, targeted straightening work is carried out in the height direction of the profile in the area before and after them. The specific method is as follows: if the data C of the corresponding point... n If the sign is greater than zero, the straightening press applies a force pointing in the direction of the sensor installation on the upper section of the corresponding position on the profile. If the data C at the corresponding point... n If the sign is less than zero, the straightening press applies a force to the upper section of the profile at the corresponding position, pointing in the opposite direction to the sensor installation direction. The magnitude of the force is determined by C. n The magnitude of the difference between the absolute value and α0 is determined.

5. The non-contact method for detecting the straightness of steel structure profiles during straightening process according to claim 1, characterized in that, In step S4, the industrial control computer processes the data, and the method for judging straightness is as follows: i) Calculate the data as U1, U2, U3, ... U respectively. n And the data are D1, D2, D3, ... D n The average values ​​of the same subscript are A1=(U1+D1) / 2, A2=(U2+D2) / 2, ... A n =(U n +D n ) / 2, to obtain the average displacement measurement data A1, A2, ... A at n measurement points. n ; ii) Find A1, A2, A3...A n The maximum value A in the series of data max and minimum value A min Calculate the absolute value of the difference between the two, Δ1; iii) By comparing Δ1 with the known straightness standard δ0 that can be used for the corresponding profile, if Δ1 is less than δ0, the straightness of the current profile is qualified; if Δ1 is greater than δ0, the straightness of the current profile is unqualified and pressure straightening is required. iv) For profiles requiring straightness correction, first define the reference distance A0 from the measured surface of the steel structure profile to the sensor. Then, use an industrial control computer to measure the data A1, A2, A2, ... A. n The differences from the reference distance A0 are δ1, δ2, δ3, ... δ n ; v) By plotting the corresponding coordinate curves and δ1, δ2, δ3, ... δ n The sign of δ is determined by the following condition: if δ1, δ2, δ3, ..., δ n A negative sign or a value below the coordinate point indicates that the straightening press needs to straighten the steel structure profile towards the laser sensor at that point. If δ1, δ2, δ3, ... δ n If the sign is positive or the value is above the coordinate point, it indicates that the straightening press needs to straighten the steel structure profile towards the side closer to the laser sensor at that point. The straightening force at the corresponding position can be set according to δ1, δ2, δ3, ... δ n The absolute value is automatically adjusted.

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