Method and device for measuring the corner of a UOE pipe

Abstract

A kind of UOE welded pipe bending edge roll angle online measurement method and device, it utilizes the point coordinate on the detected steel plate surface profile, determines the extension line H of steel plate lower surface horizontal section and the extension line V of bending edge straight section, and then calculates bending edge roll angle θ;Using the method for calculating profile curvature, the critical point a1 of steel plate profile lower surface horizontal section and edge bending section is extracted, then a2 is taken on the horizontal coordinate interval ha of steel plate lower surface horizontal section;Using the method for searching profile horizontal coordinate extreme value, the endpoint b1 of steel plate plate edge profile is extracted, then b2 is taken on the vertical coordinate interval hb of steel plate bending edge straight section profile;Using the coordinates of a1, a2, the equation of straight line H is calculated;Using the coordinates of b1, b2, the equation of straight line V is calculated, and the included angle of H and V can be obtained to obtain bending edge roll angle θ.

Description

Technical Field

[0001] This invention belongs to the field of measurement technology in steel pipe production process, specifically relating to an online measurement method and device for the bend angle of UOE welded pipe. Background Technology

[0002] Large-diameter straight seam submerged arc welded pipes, as important engineering materials, are widely used in natural gas, heating, and water supply, playing a vital role in national economic development. UOE (Underforming Oven) is one of the main forming processes for producing large-diameter straight seam submerged arc welded pipes. Using steel plates as raw materials, the process involves flaw detection, milling, forming, welding, and diameter expansion. Pre-bending is a key step in the UOE straight seam submerged arc welded pipe production line, achieved through a bending machine. Its purpose is to bend and deform the steel plate on both sides, ensuring the bending shape meets or closely approximates the curvature requirements of the produced pipe specifications, thereby guaranteeing the geometric shape and dimensional accuracy of the weld area. The bend angle refers to the angle between the horizontal section of the lower surface of the steel plate and the straight edge of the bend. It is a crucial quality control parameter in UOE production, with strict requirements. An excessively large or small bend angle will result in the steel plate's bending shape not meeting requirements, affecting subsequent pipe forming and welding processes, and ultimately impacting the final product quality. Therefore, the inspection of the bend angle has become a crucial part of the UOE welded pipe production process.

[0003] In current production, the measurement of the bend and curl of UOE welded pipes is entirely manual, typically using a combination of a ruler and a protractor. Some improved angle measuring tools exist, such as the steel plate forming angle measuring instrument disclosed in Chinese Patent No. 201020128897.3, which includes a pointer and a scale; the pointer and scale are rotatably connected; the pointer has two ends: a guide end and a test end; the scale specifically comprises a dial and a balancer, with the balancer positioned in the center of the dial; the dial is arc-shaped and has graduations. This patent combines a ruler, pointer, and scale for convenient measurement, but these existing methods still require manual operation, resulting in slow speed, low accuracy, low efficiency, inconsistent standards, and large errors, making it difficult to achieve full online coverage measurement. There are currently no mature technologies or methods for the online automatic measurement of the bend and curl of UOE welded pipes. Summary of the Invention

[0004] The purpose of this invention is to provide an online measurement method and device for the bend curl angle of UOE welded pipe. The method adopts a non-contact online measurement of the bend curl angle. Data points of the edge of the steel plate after bending are obtained by measuring the data points through a laser contour sensor to form a spatial contour line of the bend. The angle data is calculated by a curl angle calculation model, thereby accurately measuring the bend curl angle of UOE welded pipe.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] A method for online measurement of the bend radius of UOE welded pipe, comprising the following steps:

[0007] 1) The steel plate to be tested is transported to the measurement station. A laser profile sensor is installed at the measurement station. The left and right positions of the laser profile sensor are adjusted according to the size of the steel plate to be tested so that the curved edges on both sides of the steel plate to be tested are within the measurement range of the laser profile sensor.

[0008] 2) Start the laser profile sensor to measure and obtain the profile data of the curved edges on both sides of the steel plate to be measured. The profile is formed by several points, and each point contains coordinate values ​​x and y.

[0009] Let the intersection of the horizontal segment on the lower surface of the steel plate and the curved segment at the edge be endpoint a1(x1, y1). Let endpoint a2 be a point on the horizontal segment on the lower surface of the steel plate at a horizontal coordinate interval L1 from endpoint a1.

[0010] (x2, y2);

[0011] Let the upper endpoint of the curved edge on one side of the steel plate be endpoint b1(x3, y3), and let the point on the curved edge profile corresponding to the vertical coordinate interval L2 in the vertical downward direction of point b1 be endpoint b2.

[0012] (x4, y4);

[0013] Connecting endpoints b1 and b2 and extending the line to form a straight line V, can be represented as:

[0014] (y4-y3)x-(x4-x3)y-x3(y4-y3)+y3(x4-x3)=0 Equation 1

[0015] The line H formed by connecting endpoints a1 and a2 and extending it is represented as:

[0016] (y2-y1)x-(x2-x1)y-x1(y2-y1)+y1(x2-x1)=0 Equation 2

[0017] The angle θ between straight line V and straight line H is the bend angle of the steel plate, expressed as:

[0018]

[0019] 3) After obtaining the profile curve data of the bent edges on both sides of the steel plate, calculate the size of the bend angle on both sides of the steel plate at the current position according to the bend angle calculation method.

[0020] 4) During the steel plate conveying process, multiple bending angle data are measured at different positions of the steel plate according to the above method;

[0021] 5) After obtaining all the bending angle data along the length of the steel plate, calculate the maximum and minimum bending angle data, which is the range of bending angle of the UOE welded pipe.

[0022] The steel plate bend angle measurement method of this invention utilizes the coordinates of points on the detected steel plate surface contour to determine the extension line H of the horizontal segment of the lower surface of the steel plate and the extension line V of the straight edge segment of the bend, and then calculates the bend angle θ. Considering that industrial measuring devices need to be fast and stable, the actual calculation method is as follows: First, the critical point a1 between the horizontal segment of the lower surface of the steel plate contour and the edge bend segment is extracted by calculating the curvature of the contour line. Then, a2 is taken at a horizontal coordinate interval ha on the horizontal segment of the lower surface. The endpoint b1 of the steel plate edge contour is extracted by searching for the extreme values ​​of the horizontal coordinates of the contour. Then, b2 is taken at a vertical coordinate interval hb on the straight edge segment contour. Using the coordinates of a1 and a2, the equation of the straight line H is calculated; using the coordinates of b1 and b2, the equation of the straight line V is calculated. The bend angle θ can be obtained by calculating the angle between H and V.

[0023] The present invention also provides a measuring device for the online measurement method of UOE welded pipe bend curl angle, comprising:

[0024] At least one horizontally movable device;

[0025] At least one laser profile sensor is mounted on the horizontally movable device and corresponds to the bottom bend of the steel plate to be measured.

[0026] A positioning signal detector is installed above one side of the steel plate to be tested;

[0027] The controller is equipped with a process signal interface unit and a bend corner model calculation unit. The laser contour sensor and the position signal detector are both connected to the bend corner model calculation unit through the process signal interface unit.

[0028] Preferably, two horizontally movable devices are provided, each equipped with a laser profile sensor, corresponding to the two bottom bends of the steel plate to be tested.

[0029] Preferably, the horizontally movable device is a mobile trolley.

[0030] The horizontal moving device described in this invention is installed below both sides of the steel plate to be tested after bending. It receives the control signal output by the bending angle calculation and control unit to realize the horizontal movement of the wire along the transverse direction of the steel plate.

[0031] The laser profile sensor is mounted on a horizontal moving device. It is a sensor that uses a non-contact method to measure the profile of the curved edge on the lower surface of a steel plate. It is used to measure the profile data of the curved edge and transmit the results to the curve angle calculation and control unit in real time.

[0032] The arrival signal detector is a device that measures whether the steel plate to be measured has arrived at the measuring station. When a steel plate arrives, it will output a signal to the bending corner calculation and control unit.

[0033] The process signal interface unit is a data signal communication device that receives the specification data and inspection standard requirements of the steel plate to be tested and outputs this data information to the bend corner calculation and control unit. The bend corner calculation and control unit is a computer device with signal and contour data acquisition, contour modeling, data calculation and processing, corner model calculation, and horizontal motion control functions. It receives relevant contour data, position signals, steel plate specifications, and inspection standards from the laser contour sensor, position signal detector, and process signal interface unit, and obtains the bend corner size of the UOE welded pipe through bend corner model calculation and analysis.

[0034] After bending, the steel plate to be inspected is placed horizontally at a measuring station. Measuring devices are installed directly below the bends on both sides of the steel plate. Laser profile sensors are used to measure the profile curve data at the bends on the lower surface of the steel plate. The angle between the horizontal section of the steel plate and the straight edge of the bend is calculated using a curl angle calculation model; this is the curl angle at that location. During the transport of the steel plate, the curl angle at various positions along its length is measured, and the range from the minimum to the maximum value represents the curl angle range of the UOE welded pipe.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] This invention employs a non-contact method to achieve online automatic measurement of the bend and curl angle of UOE welded pipes. It can obtain bend and curl angle data in real time during the production process without stopping the machine, which is very helpful for ensuring product quality and guiding production. At the same time, the method described in this invention is easy to implement and use in actual production, and has strong practicality. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the online measurement method for the bend angle of UOE welded pipe described in this invention;

[0038] Figure 2 This is a schematic diagram of the online measurement device for the bend angle of UOE welded pipe described in this invention;

[0039] Figure 3 This is a schematic diagram of the online measurement device for the bend angle of UOE welded pipe described in this invention;

[0040] Figure 4 This is a schematic diagram of an embodiment of the online measurement method for the bend angle of UOE welded pipe described in this invention;

[0041] Figure 5This is a flowchart of the online measurement method for the bend angle of UOE welded pipe described in this invention. Detailed Implementation

[0042] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0043] See Figure 1 The online measurement method for the bend angle of UOE welded pipe described in this invention includes the following steps:

[0044] 1) The steel plate to be tested is transported to the measurement station. A laser profile sensor is installed at the measurement station. The left and right positions of the laser profile sensor are adjusted according to the size of the steel plate to be tested so that the curved edges on both sides of the steel plate to be tested are within the measurement range of the laser profile sensor.

[0045] 2) Start the laser profile sensor to measure and obtain the profile data of the curved edges on both sides of the steel plate to be measured. The profile is formed by several points, and each point contains coordinate values ​​x and y.

[0046] Let the intersection of the horizontal segment on the lower surface of the steel plate and the curved segment at the edge be endpoint a1(x1, y1). Let endpoint a2 be a point on the horizontal segment on the lower surface of the steel plate at a horizontal coordinate interval L1 from endpoint a1.

[0047] (x2, y2);

[0048] Let the upper endpoint of the curved edge on one side of the steel plate be endpoint b1(x3, y3), and let the point on the curved edge profile corresponding to the vertical coordinate interval L2 in the vertical downward direction of point b1 be endpoint b2.

[0049] (x4, y4);

[0050] Connecting endpoints b1 and b2 and extending the line to form a straight line V, can be represented as:

[0051] (y4-y3)x-(x4-x3)y-x3(y4-y3)+y3(x4-x3)=0 Equation 1

[0052] The line H formed by connecting endpoints a1 and a2 and extending it is represented as:

[0053] (y2-y1)x-(x2-x1)y-x1(y2-y1)+y1(x2-x1)=0 Equation 2

[0054] The angle θ between straight line V and straight line H is the bend angle of the steel plate, expressed as:

[0055]

[0056] 3) After obtaining the profile curve data of the bent edges on both sides of the steel plate, calculate the size of the bend angle on both sides of the steel plate at the current position according to the bend angle calculation method.

[0057] 4) During the steel plate conveying process, multiple bending angle data are measured at different positions of the steel plate according to the above method;

[0058] 5) After obtaining all the bending angle data along the length of the steel plate, calculate the maximum and minimum bending angle data, which is the range of bending angle of the UOE welded pipe.

[0059] See Figure 2 , Figure 3 The present invention also provides a measuring device for the online measurement method of the bend curl angle of the UOE welded pipe, comprising:

[0060] Two horizontally movable devices 1 and 1';

[0061] Two laser contour sensors 2 and 2' are mounted on the horizontally movable devices 1 and 1', respectively corresponding to the two curved edges at the bottom of the steel plate 100 to be tested; the steel plate 100 to be tested is conveyed by the conveyor roller 200;

[0062] The positioning signal detector 3 is positioned above one side of the steel plate 100 to be tested;

[0063] The controller 4 is equipped with a process signal interface unit 5 and a bend corner model calculation unit. The two laser contour sensors and the position signal detector are all connected to the bend corner model calculation unit through the process signal interface unit.

[0064] Preferably, the horizontally movable device is a mobile trolley.

[0065] See Figure 5 The method for measuring the bend angle of a steel plate according to the present invention includes the following steps:

[0066] The first step is that the bending and curling calculation control unit measures the arrival signal of the steel plate at the inspection station through the arrival signal detector to determine whether a steel plate has entered the inspection station. If so, proceed to the second step; otherwise, continue to wait.

[0067] The second step is to read the current steel plate specifications and inspection standard data through the process signal interface unit and transmit the data to the bending and angular calculation control unit.

[0068] The third step is to calculate the position of the bend according to the size of the steel plate and control the horizontal moving device to move the laser contour sensor to the position of the bend on both sides of the steel plate so that the bend on both sides of the steel plate is within the measurement range of the sensor.

[0069] The fourth step involves using a laser contour sensor to collect real-time data on the contour curves of the curved edges on both sides of the lower surface of the steel plate, and then sending this data to the curve angle calculation and control unit.

[0070] The fifth step is to process and analyze the bending profile curve data of the bending edge and calculate the size of the bending edge corner on both sides of the steel plate at the current position according to the bending edge corner calculation method.

[0071] Step 6: Repeat steps 4 and 5 until the entire steel plate is measured. Once the entire steel plate is measured, proceed to step 7. There are several ways to determine whether the measurement of the entire steel plate is complete. This invention uses a position signal sensor to determine whether there is a steel plate at the detection station. Alternatively, it can be determined based on data from a laser contour sensor.

[0072] Step 7: After obtaining all the bending angle data along the length of the steel plate, the bending angle calculation and control unit compares and analyzes all the data to calculate the maximum and minimum data, which are the range of bending angle of the UOE welded pipe.

[0073] Step 8: Determine if the measurement is complete. If not, return to step 1 and continue waiting for the measurement of the new steel plate.

[0074] Example

[0075] The steel plate 100 to be tested is horizontally transported into the measurement station by the conveyor roller 200. After the arrival signal detector detects that the steel plate 100 has arrived at the measurement station, the system is started. The bend and roll angle calculation and control unit collects data such as the specifications and inspection standards of the steel plate 100 to be tested at the current measurement station through the process signal interface.

[0076] The bend angle calculation and control unit controls the horizontal moving devices 1 and 1' to move the laser profile sensors 2 and 2' to the detection positions of the left and right bends of the steel plate 100 according to the size information of the steel plate 100 to be tested. When the width of the steel plate 100 is fixed, the sensor measurement range is fixed, and the steel plate 100 does not deviate on the roller conveyor, the detection position is a fixed value, and its distance from the edge of the steel plate should be slightly less than 1 / 2 of the sensor's field of view. For example, when the laser profile sensor's field of view is 500mm, the detection position can be set to 200mm from the edge of the steel plate.

[0077] Laser profile sensors 2 and 2' are activated to measure the profile curve of the lower surface of the steel plate 100mm from which the curve is obtained, and then sent to the bend angle calculation and control unit. The bend angle calculation and control unit uses the curve data for calculation. Taking the calculation of the bend angle on the left side as an example, as follows... Figure 4 As shown, by differentiating the contour curve, the curvature of the curve can be obtained. Find the intersection point a1 of the horizontal segment and the curved segment of the contour line and set it as the origin (coordinates 0, 0). In this embodiment, ha is set to 100. Then the point on the contour line at the horizontal coordinate plus 100 is a2 (coordinates 100, 0). The straight line H can be expressed as: y = 0.

[0078] Search for the minimum point b1 (coordinates -300, 200) on the contour line, and then subtract 20 from the ordinate on the contour of the curved and straight edge segments (hb is set to 20 in this embodiment) to obtain b2 (coordinates -265, 180). The straight line V can then be expressed as: 4x + 7y - 200 = 0.

[0079] Therefore, the bend angle θ is: θ = 30°.

[0080] During the transport process, the steel plate 100 to be tested repeats the above steps to measure the bends and creases at different positions of the steel plate until the entire steel plate is measured.

[0081] The bend angle calculation and control unit performs statistical analysis on all measured bend angle data to obtain the minimum value θ. min =25° and maximum value θ max =30° means that the bend angle of this steel plate is between 25° and 30°.

Claims

1. A method for online measurement of the bend radius of UOE welded pipe, characterized in that, Includes the following steps: 1) The steel plate to be tested is transported to the measurement station. A laser profile sensor is installed at the measurement station. The left and right positions of the laser profile sensor are adjusted according to the size of the steel plate to be tested so that the curved edges on both sides of the steel plate to be tested are within the measurement range of the laser profile sensor. 2) Start the laser profile sensor to measure and obtain the profile data of the curved edges on both sides of the steel plate to be measured. The profile is formed by several points, and each point contains coordinate values ​​x and y. Let the intersection of the horizontal section of the lower surface of the steel plate and the curved section at the edge be the endpoint a1(x1, y1), and the endpoint a2(x2, y2) on the horizontal section of the lower surface of the steel plate be a horizontal coordinate distance L1 from the endpoint a1. Let the upper end point of the curved edge on one side of the steel plate be the end point b1(x3, y3), and the point on the curved edge profile corresponding to the vertical coordinate interval L2 in the vertical downward direction of this point b1 be the end point b2(x4, y4). Connecting endpoints b1 and b2 and extending the line to form a straight line V, can be represented as: (y4-y3)x-(x4-x3)y-x3(y4-y3)+y3(x4-x3)=0 Equation 1 The line H formed by connecting endpoints a1 and a2 and extending it is represented as: (y2-y1)x-(x2-x1)y-x1(y2-y1)+y1(x2-x1)=0 Equation 2 The angle θ between straight line V and straight line H is the bend angle of the steel plate, expressed as: 3) After obtaining the profile curve data of the bent edges on both sides of the steel plate, calculate the size of the bend angle on both sides of the steel plate at the current position according to the bend angle calculation method. 4) During the steel plate conveying process, multiple bending angle data are measured at different positions of the steel plate according to the above method; 5) After obtaining all the bending angle data along the length of the steel plate, calculate the maximum and minimum bending angle data, which is the range of bending angle of the UOE welded pipe.

2. A measuring device for online measurement of the bend angle of UOE welded pipe as described in claim 1, characterized in that, include: At least one horizontally movable device; At least one laser profile sensor is mounted on the horizontally movable device, corresponding to the bottom bend of the steel plate to be measured; A positioning signal detector is installed above one side of the steel plate to be tested; The controller is equipped with a process signal interface unit and a bend corner model calculation unit. The laser contour sensor and the position signal detector are both connected to the bend corner model calculation unit through the process signal interface unit.

3. The measuring device as described in claim 2, characterized in that, Two horizontally movable devices are provided, each equipped with a laser profile sensor, corresponding to the two bottom bends of the steel plate to be measured.

4. The measuring device as described in claim 2 or 3, characterized in that, The horizontally movable device is a mobile trolley.

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