A method for automatic detection of geometric parameters of seamless steel pipes

Abstract

The present invention discloses an automatic detection device and method for geometric parameters of seamless steel pipes, comprising a conveying roller, a laser sensor, a photoelectric sensor and a rotating mechanism; the laser sensor and the photoelectric sensor are electrically connected to a controller; the conveying roller has a V-shaped groove for placing a workpiece, the laser sensor can reciprocate along the X, Y and Z directions, and the rotating mechanism can be lifted and lowered along the Z axis to separate the rotating mechanism from the workpiece or drive the workpiece to rotate. The present invention only requires one laser shift sensor to complete the measurement of multiple geometric parameters such as diameter, roundness, straightness and length of seamless steel pipes, does not require the cooperation of multiple laser probes, has a simple structure, and provides a laser detection system with low cost, high detection accuracy and full detection items for seamless steel pipe manufacturers.

Description

Technical Field

[0001] The present invention relates to the field of detection technology, and in particular to an automatic detection device and method for geometric parameters of a seamless steel pipe. Background Art

[0002] In recent years, the domestic seamless steel pipe industry has entered a new era. After more than ten years of accumulation of technical experience, China's seamless steel pipe industry ranks among the best in the world. And with the advancement of science and technology, the production process level of my country's seamless steel pipe enterprises has been further improved. Varieties, specifications, characteristics, etc. have become the breakthrough for enterprises to break through the dilemma. In order to meet the requirements of industrial applications and improve product quality, pipe manufacturers must strictly control the outer surface geometric dimension accuracy of seamless steel pipes, such as diameter, roundness, straightness and length.

[0003] At present, seamless steel pipe manufacturers at home and abroad still use manual handheld measuring equipment to measure the diameter of seamless steel pipes. The disadvantages are obvious. The labor intensity is high, the mode is random inspection, the detection points are generally no more than 2, and the detection accuracy is low. It is understood that there is a diameter gauge on the market-a dual-axis diameter gauge with an adjustable measuring range. This product can be directly installed on the production line for online measurement, and can also be installed on the flaw detection line and the inspection line to measure the outer diameter of the finished pipe. However, this measuring equipment can only measure the single parameter of diameter, and cannot detect its length, out-of-roundness, and straightness. The existing technology also has other equipment for measuring the diameter, roundness, straightness and length of seamless steel pipes, but there are many test probes and the equipment cost is relatively high. Summary of the invention

[0004] In order to solve the technical problems that the testing equipment in the prior art cannot simultaneously measure the geometric parameters of the seamless steel pipe, such as diameter, roundness, straightness and length, or the testing equipment has a complex structure and high cost, the present invention provides an automatic detection device and method for the geometric parameters of seamless steel pipes to solve the above problems.

[0005] The present invention proposes an automatic detection device and method for geometric parameters of seamless steel pipes, comprising a conveying roller for conveying a workpiece, a laser sensor for measuring distance, a photoelectric sensor for controlling the motion state of the workpiece, and a rotating mechanism; the laser sensor and the photoelectric sensor are electrically connected to a controller; the conveying roller has a V-shaped groove for placing the workpiece, the laser sensor can reciprocate along the X direction, so that the laser sensor can measure the axial dimensions of the workpiece at different positions, the laser sensor can also reciprocate along the Y direction, so that the laser sensor is aligned with the center of the V-shaped groove, the laser sensor can also reciprocate along the Z direction, and is used to adjust the distance between the laser sensor and the workpiece, and the rotating mechanism can be raised and lowered along the Z-axis direction, so that the rotating mechanism is separated from the workpiece or drives the workpiece to rotate.

[0006] Furthermore, it also includes an X-axis driving module, a Y-axis driving module and a Z-axis driving module which are sequentially connected to form a three-level driving module, and the laser sensor is connected to the last-level driving module; the X-axis driving module, the Y-axis driving module and the Z-axis driving module are all electrically connected to the controller; the X-axis driving module drives the laser sensor to reciprocate along the axial direction of the workpiece; the Y-axis driving module drives the laser sensor to move axially perpendicular to the workpiece in a horizontal plane; the Z-axis driving module drives the laser sensor to move axially perpendicular to the workpiece in a vertical plane.

[0007] Furthermore, it also includes a conveying motor, and a plurality of conveying rollers are arranged along the axial direction of the workpiece, and the conveying motor is drivingly connected to one or more of the conveying rollers.

[0008] Furthermore, the rotating mechanism includes two rotating drive groups arranged along the length direction of the workpiece; the rotating drive groups include a frame, a rotating motor movably connected to the frame, and a friction wheel connected to the output shaft of the rotating motor, and the friction wheel can contact the outer surface of the workpiece and drive the workpiece to rotate.

[0009] The present invention also proposes a detection method, which uses the above-mentioned automatic detection device for geometric parameters of seamless steel pipes, and includes the following steps:

[0010] S1: Align the laser sensor; move the laser sensor along the Y direction so that the laser sensor is aligned with the center of the V-groove, and record the distance M between the laser sensor and the bottom of the V-groove at this time.

[0011] S2: conveying the workpiece; conveying the workpiece on the conveying roller, using the photoelectric sensor to control the start and stop of the workpiece, so that the workpiece is directly above the laser sensor. At this time, the workpiece is outside the measuring range of the laser sensor.

[0012] S3: Diameter measurement: adjust the laser sensor along the Z direction so that the workpiece is within the measurement range of the laser sensor, measure the distance B between the laser sensor and the workpiece surface at this time, and calculate the theoretical diameter D and actual diameter D′ of the workpiece N .

[0013] S4: Laser sensor reset: Move the laser sensor along the Z direction so that the workpiece is outside the measuring range of the laser sensor.

[0014] Furthermore, the theoretical diameter D of the workpiece is:

[0015] ,

[0016] Among them, f is the pulse signal frequency sent by the controller, k 1 A is the ratio of the pulse equivalent of the driving module that drives the laser sensor to move along the Z direction to the distance the driving module drives the laser sensor to move;1 A is the number of pulses in the register of the controller after step S1; 2 is the number of pulses in the register of the controller after step S3.

[0017] Furthermore, step S3 also includes workpiece length measurement. First, the laser sensor is moved along the X direction to one axial end of the workpiece, and the number of pulses in the register is recorded as C. 1 Then move the laser sensor along the X direction to the other end of the workpiece and record the number of pulses in the register as C. 2 , then the length L of the workpiece is:

[0018] L = k 2 *(C 2 -C 1 )*f

[0019] , where f is the pulse signal frequency sent by the controller, k 2 It is the ratio of the pulse equivalent of the driving module that drives the laser sensor to move along the X direction to the distance the driving module drives the laser sensor to move.

[0020] Furthermore, the actual diameter measurement step of the workpiece in step S3 includes:

[0021] S31: Establish a rectangular coordinate system with the rotation axis O of the workpiece as the origin and the line connecting the laser sensor and the rotation axis O as the Y axis. Use the rotating mechanism to rotate the workpiece N times. The Nth rotation angle θ N , calculate the theoretical diameter D of the workpiece after the Nth rotation N , and the coordinate point P under the theoretical diameter is obtained N (x N ,y N ),in Among them, P N (x N ,y N ) is the coordinate of the Nth point on the workpiece surface.

[0022] S32: Based on the coordinate point P in step S31 N (x N ,y N ), and use the least square method to calculate the actual center coordinates O'(x', y') of the workpiece.

[0023] S33: Calculate the actual diameter of the workpiece

[0024] Furthermore, the straightness of the workpiece is:

[0025]

[0026] , where D' max is the actual diameter of the workpiece (D' 1 , D′ 2 , D′ 3 ,…,D′ N ), D' min is the actual diameter of the workpiece (D' 1 , D′ 2 , D′ 3 ,…,D′ N ), L is the axial length of the workpiece.

[0027] Furthermore, the roundness of the workpiece is:

[0028] ,

[0029] Among them, D' max is the actual diameter of the workpiece (D' 1 , D′ 2 , D′ 3 ,…,D′ N ), D' min is the actual diameter of the workpiece (D' 1 , D′ 2 , D′ 3 ,…,D′ N ) is the minimum value among .

[0030] The beneficial effects of the present invention are:

[0031] (1) The automatic detection device and method for geometric parameters of seamless steel pipes described in the present invention only require one laser shift sensor to complete the measurement of multiple geometric parameters such as diameter, roundness, straightness and length of seamless steel pipes. It does not require the coordination of multiple laser probes and has a simple structure. It provides seamless steel pipe manufacturers with a laser detection system with low cost, high detection accuracy and comprehensive detection items.

[0032] (2) The present invention uses the displacement of the laser sensor and the number of pulses of the driving module as known quantities to calculate the theoretical diameter of the seamless steel pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0034] Figure 1 It is a front view of a specific embodiment of the automatic detection device for geometric parameters of seamless steel pipes according to the present invention (the rotating mechanism is not shown);

[0035] Figure 2 yes Figure 1 AA section view;

[0036] Figure 3 yes Figure 1 The middle is a schematic diagram of the matching relationship between the conveying roller and the workpiece;

[0037] Figure 4 It is a three-dimensional diagram of the automatic detection device for geometric parameters of seamless steel pipes according to the present invention;

[0038] Figure 5 This is a schematic diagram when the laser sensor moves to the leftmost end of the workpiece;

[0039] Figure 6 This is a schematic diagram when the laser sensor moves to the rightmost end of the workpiece;

[0040] Figure 7 It is a schematic diagram of the laser sensor measuring the diameter of the workpiece;

[0041] Figure 8 It is a schematic diagram of the position change of point P1 on the workpiece surface after the workpiece rotates for the first time;

[0042] Fig. 9 It is a schematic diagram of the position change of point P1 and point P2 on the workpiece surface after the workpiece rotates for the second time;

[0043] Fig.10 It is a flow chart of the detection method of the present invention.

[0044] In the figure, 1, workpiece, 2, conveying roller, 201, V-groove, 3, laser sensor, 4, photoelectric sensor, 5, rotating mechanism, 501, frame, 502, rotating motor, 503, friction wheel, 504, first cylinder, 505, second cylinder, 6, chassis, 7, base, 8, conveying motor, 9, first conveying roller, 10, second conveying roller, 11, third conveying roller, 12, belt, 13, X-axis motor, 14, Y-axis motor, 15, Z-axis motor, 16, screw, 17, fixed slide rail, 18, moving slider. DETAILED DESCRIPTION

[0045] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0046] The workpiece 1 in the present invention is a seamless steel pipe to be tested, specifically a seamless steel pipe with a circular cross section. The X direction representing the movement direction of each component in the present invention refers to a direction parallel to the central axis of the workpiece 1, the Y direction refers to a direction perpendicular to the central axis of the workpiece 1 in a horizontal plane, and the Z direction refers to a direction perpendicular to the central axis of the workpiece 1 in a vertical plane, that is, parallel to the gravity direction in the working state of the present invention.

[0047] A seamless steel pipe geometric parameter automatic detection device includes a conveying roller 2 for conveying a workpiece 1, a laser sensor 3 for distance measurement, a photoelectric sensor 4 for controlling the motion state of the workpiece 1, and a rotating mechanism 5; the laser sensor 3 and the photoelectric sensor 4 are electrically connected to a controller; the conveying roller 2 has a V-shaped groove 201 for placing the workpiece 1, and the V-shaped groove 201 can limit the three directional degrees of freedom of the workpiece 1: rotational movement around the X axis, rotational movement around the Z axis, and translational movement along the Y axis. The laser sensor 3 can reciprocate along the X direction so that the laser sensor 3 measures the dimensions of different axial positions of the workpiece 1, and this function can measure the axial length L of the workpiece 1. The laser sensor 3 can also reciprocate along the Y direction so that the laser sensor 3 is aligned with the center of the V-shaped groove 201. The laser sensor 3 can also reciprocate along the Z direction to adjust the distance between the laser sensor 3 and the workpiece 1. The rotating mechanism 5 can be lifted and lowered along the Z axis direction so that the rotating mechanism 5 is separated from the workpiece 1 or drives the workpiece 1 to rotate, and this function can realize the measurement of the roundness Q of the workpiece 1.

[0048] The laser sensor 3 is a distance measuring sensor with high measurement accuracy and can return the measured distance value to the controller.

[0049] Embodiment 1

[0050] like Figure 1-Figure 4 As shown, an automatic detection device for geometric parameters of seamless steel pipes includes a conveying roller 2 for conveying a workpiece 1, a laser sensor 3 for measuring distance, a photoelectric sensor 4 for controlling the motion state of the workpiece 1, and a rotating mechanism 5; the laser sensor 3 and the photoelectric sensor 4 are electrically connected to the controller; the conveying roller 2 has a V-shaped groove 201 for placing the workpiece 1.

[0051] like Figure 1 As shown, the automatic detection device for geometric parameters of seamless steel pipes is arranged in a chassis 6, and the chassis 6 is divided into two layers, the upper layer is used to place the automatic detection device for geometric parameters of seamless steel pipes, and the lower layer is used to store power equipment. A base 7 is fixed to the upper layer of the chassis 6, and the conveying roller 2 is rotatably connected to the base 7.

[0052] A conveying motor 8 is also fixed to the upper layer of the chassis 6, and the conveying motor 8 is drivingly connected to one or more of the conveying rollers 2. The conveying motor 8 is preferably a unidirectional asynchronous motor, which can reduce the output speed and make the workpiece 1 move forward slowly and evenly. Figure 2In the figure, six conveying rollers 2 are arranged along the axial direction of the workpiece 1, the conveying motor 8 is connected to the first conveying roller 9 through the belt 12, the first conveying roller 9 is connected to the second conveying roller 10 through the belt 12, the second conveying roller 10 is connected to the third conveying roller 11 through the belt 12, and there can be one or more idle wheels between the first conveying roller 9 and the second conveying roller 10, and between the second conveying roller 10 and the first conveying roller 9. The idle wheel is the conveying roller 2 that is not connected to the belt 12. During the conveying process of the workpiece 1, the idle wheel mainly plays a role in reducing friction resistance.

[0053] The conveying motor 8 is also electrically connected to the controller. The trigger signal or disconnection signal sent by the photoelectric sensor 4 to the controller can control the start and stop of the conveying motor 8, thereby controlling the movement of the workpiece 1. When the workpiece 1 stops being conveyed, the workpiece 1 is directly below the laser sensor 3, realizing automatic control to convey the workpiece 1 into the test area.

[0054] The translational movement of the laser sensor 3 is realized by an X-axis driving module, a Y-axis driving module and a Z-axis driving module which are sequentially connected to form a three-level driving module, and the laser sensor 3 is connected to the last-level driving module; the X-axis driving module, the Y-axis driving module and the Z-axis driving module are all electrically connected to the controller; the X-axis driving module drives the laser sensor 3 to reciprocate along the axial direction of the workpiece 1; the Y-axis driving module drives the laser sensor 3 to move axially perpendicular to the workpiece 1 in a horizontal plane; the Z-axis driving module drives the laser sensor 3 to move axially perpendicular to the workpiece 1 in a vertical plane.

[0055] Specifically, Figure 4 As shown, the X-axis drive module includes an X-axis motor 13 and a screw mechanism connected to the output shaft of the X-axis motor 13, the screw mechanism generally includes a screw 16, a fixed slide rail 17 and a movable slider 18, the screw 16 and the fixed slide rail 17 both extend along the X-axis direction, the fixed slide rail 17 is fixed to the chassis 6, the screw 16 is fixedly connected to the output shaft of the X-axis motor 13 and the screw 16 is rotatably connected to the fixed slide rail 17, the movable slider 18 is threadedly matched with the screw 16 and the movable slider 18 is slidably connected to the fixed slide rail 17, when the X-axis motor 13 is started, the movable slider 18 slides back and forth along the X-axis direction.

[0056] Similarly, the Y-axis driving module includes a Y-axis motor 14 and a screw mechanism connected to the output shaft of the Y-axis motor 14, and the Z-axis driving module includes a Z-axis motor 15 and a screw mechanism connected to the output shaft of the Z-axis motor 15. The three driving modules are connected in sequence, and the connection order of the three can be interchanged. The laser sensor 3 is connected to the last-stage driving module. In this embodiment, the last-stage driving module is the Z-axis driving module, and the first-stage driving module is the X-axis driving module. The Y-axis driving module is connected to the moving slider 18 of the X-axis driving module, and the Z-axis driving module is connected to the moving slider 18 of the Y-axis driving module.

[0057] In this embodiment, when the laser sensor 3 moves along the X-axis, in order to accurately measure the length of the workpiece 1, the laser sensor 3 needs to immediately issue a stop movement command when it moves to the outside of the workpiece 1. Therefore, the X-axis motor 13 preferably uses a servo motor with higher precision, and the Y-axis motor 14 and the Z-axis motor 15 can choose a stepper motor. The power sources of the servo motor and the stepper motor are both alternating current. When the laser sensor 3 is driven to generate displacement, the displacement of the laser sensor 3 can be calculated by the change in the number of pulses recorded in the register in the controller.

[0058] Embodiment 2

[0059] On the basis of the first embodiment, the rotating mechanism 5 includes two rotating drive groups arranged along the length direction of the workpiece 1; the rotating drive group includes a frame 501, a rotating motor 502 movably connected to the frame 501, and a friction wheel 503 connected to the output shaft of the rotating motor 502, and the friction wheel 503 can contact the outer surface of the workpiece 1 and drive the workpiece 1 to rotate. The rotating motor 502 can be a DC motor, which is used to drive the friction wheel 503 to rotate. The frame 501 is movably connected to the rotating motor 502, which means that the frame 501 can drive the rotating motor 502 to approach or move away from the workpiece 1. When the workpiece 1 is directly below the laser sensor 3, the position of the rotating motor 502 is first adjusted so that the friction wheel 503 fits the circumferential outer surface of the workpiece 1. After the rotating motor 502 is started, it can drive the workpiece 1 to rotate a certain angle, and then the rotating motor 502 is withdrawn to avoid blocking the measurement of the laser sensor 3, and then the laser sensor 3 is adjusted to the measurement area to measure the surface size of the workpiece 1.

[0060] like Figure 4 As shown, the first cylinder 504 and the second cylinder 505 are fixed on the frame 501 in sequence, the output end of the first cylinder 504 is connected to the second cylinder 505, and the output end of the second cylinder 505 is connected to the rotating motor 502. The first cylinder 504 can realize linear motion in the Y-axis direction, and the second cylinder 505 can realize linear motion in the Z-axis direction.

[0061] In the actual detection process, since the seamless steel pipe will rotate with the friction wheel 503 during the detection process, the axis deviation will inevitably occur, which will cause errors. In this device, the main reason for the axis deviation is the tilt of the axis of the workpiece 1. The tilt of the axis of the workpiece 1 is mainly because the conveying roller 2 cannot achieve the ideal vertical and horizontal alignment when it is arranged, and the force side will cause the workpiece 1 to tilt slightly when the friction wheel 503 drives it to rotate. In order to ensure the accuracy range requirements, the installation accuracy deviation of the first cylinder 504, the second cylinder 505 and the conveying roller 2 cannot exceed ±4mm. Since the length of the workpiece 1 is about 600mm, in order to avoid the workpiece 1 being slightly tilted on the force side after being squeezed by the friction wheel 503, it is preferably used. A symmetrically distributed rotating mechanism 5 offsets this force, and the deviation caused by the tilt of the workpiece 1 can be ignored.

[0062] Embodiment 3

[0063] A detection method, which uses the above-mentioned automatic detection device for geometric parameters of seamless steel pipes, includes the following steps:

[0064] S1: centering the laser sensor 3; moving the laser sensor 3 along the Y direction so that the laser sensor 3 is aligned with the center of the V-shaped groove 201, and recording the distance M between the laser sensor 3 and the bottom of the V-shaped groove 201 at this time.

[0065] Since the position of the conveying roller 2 is fixed, the center axis of the workpiece 1 is limited by the V-shaped groove 201 in the conveying roller 2, so this step only needs to be adjusted when the device is used for the first time. The specific operation method is to first adjust the laser sensor 3 to be within the measurement range in the height direction (when the distance between the laser sensor 3 and the object reflection surface is not between 65mm and 105mm, the displayed data is "#"), then move the laser sensor 3 along the Y-axis direction, and then measure the length of a certain conveying roller 2 along the Y-axis direction and select the middle position point, or place a standard round tube on the conveying roller 2 (the center of the standard round tube coincides with the center of the V-shaped groove 201), and then move the laser sensor 3 along the Y-axis, measure the diameter endpoints of the standard round tube, and then return to the center position of the two diameter endpoints. For example, when the laser sensor 3 initially detects the standard round tube signal, the register is assigned a value of 0. When the laser sensor 3 changes from the return data to the detection data of "#" (i.e., an invalid value), the number of pulses in the register at this time is recorded, and then the laser sensor 3 is moved in the opposite direction by half the number of pulses, which is the center position of the conveying roller 2. After the laser sensor 3 is aligned, the standard steel pipe is taken out.

[0066] S2: conveying the workpiece 1; conveying the workpiece 1 on the conveying roller 2, using the photoelectric sensor 4 to control the start and stop of the workpiece 1, so that the workpiece 1 is directly above the laser sensor 3, and at this time the workpiece 1 is outside the measuring range of the laser sensor 3.

[0067] Assume that the photoelectric sensor 4 is arranged in front of the laser sensor 3 along the conveying direction of the workpiece 1, and the distance between the photoelectric sensor 4 and the laser sensor 3 is less than the length of the workpiece 1. The conveying motor 8 is first controlled to start by the start button. At this time, there is no workpiece 1 within the detection range of the photoelectric sensor 4, and the workpiece 1 is conveyed on the conveying roller 2. When the photoelectric sensor 4 detects the workpiece 1, the conveying motor 8 stops. At this time, the laser sensor 3 is located directly above the workpiece 1, but the laser sensor 3 needs to move downward to adjust to the measurement range.

[0068] S3: Diameter measurement: adjust the laser sensor 3 along the Z direction so that the workpiece 1 is within the measurement range of the laser sensor 3, measure the distance B between the laser sensor 3 and the surface of the workpiece 1 at this time, and calculate the theoretical diameter D and actual diameter D′ of the workpiece 1 N .

[0069] S4: Reset the laser sensor 3: Move the laser sensor 3 along the Z direction so that the workpiece 1 is outside the measurement range of the laser sensor 3. This prevents the laser sensor 3 from interfering with the rotating mechanism 5 and prevents the laser sensor 3 from continuously outputting unnecessary detection signals.

[0070] like Figure 7 As shown, assuming that the distance between the receiving plane of the laser sensor 3 and the center of the V-shaped groove 201 of the conveying roller 2 is M when the receiving plane is at the origin, the ratio of the pulse equivalent of the Z-axis motor 15 to the moving distance of the laser sensor 3 along the Z-axis is k 1 , when the laser sensor 3 is in the initial position, the pulse number of the register is A 1 When the laser sensor 3 moves vertically into the measurement range, the number of pulses in the register is A. 2 , at this time, the laser sensor 3 returns the measurement data B (i.e., the distance between the laser sensor 3 and the reflective surface of the workpiece 1). Assuming that the theoretical diameter of the workpiece 1 is D, the distance formula between the two points can be obtained:

[0071]

[0072] By transforming the above formula, the theoretical diameter D of the workpiece 1 is:

[0073] ,

[0074] Among them, f is the frequency of the pulse signal sent by the controller.

[0075] To simplify the calculation, the register is usually assigned a value of 0 when the laser sensor 3 is in the initial position, that is, A 1 =0, then the theoretical diameter formula of workpiece 1 can be simplified to

[0076]

[0077] Embodiment 4

[0078] On the basis of the third embodiment, step S3 further includes measuring the length of the workpiece 1. First, the laser sensor 3 is moved along the X direction to one axial end of the workpiece 1, and the number of pulses in the register is recorded as C. 1 Then move the laser sensor 3 along the X direction to the other end of the workpiece 1, and record the number of pulses in the register as C 2 , then the length L of workpiece 1 is:

[0079] L = k 2 *(C 2 -C 1 )*f

[0080] , where f is the pulse signal frequency sent by the controller, k 2 It is the ratio of the pulse equivalent of the driving module that drives the laser sensor 3 to move along the X direction to the moving distance of the laser sensor 3 driven by the driving module.

[0081] Since the conveying motor 8 adopts an asynchronous motor with low cost and accuracy, there is a certain time difference in the whole process from the change of the detection signal of the photoelectric sensor 4 to the receipt of the stop signal by the conveying motor 8 and then to the stop of the conveying motor 8. As a result, it is impossible to accurately locate the relative position of the workpiece 1 and the laser sensor 3 simply by the photoelectric sensor 4. For this reason, the present invention realizes accurate measurement by the laser sensor 3. As shown in the figure, the workpiece 1 is conveyed to the left, and the photoelectric sensor 4 is located on the right side of the laser sensor 3, with a spacing approximately equal to the length of the workpiece 1. When the photoelectric sensor 4 does not detect the workpiece 1, it indicates that the workpiece 1 has completely passed the photoelectric sensor 4. In the absence of signal delay, the laser sensor 3 will be directly opposite the left end of the workpiece 1. However, due to the existence of signal delay, the workpiece 1 will continue to move to the left and exceed the laser sensor 3. Therefore, it is necessary to move the laser sensor 3 to the left first. When the data returned by the laser sensor 3 changes from a valid value to an invalid value, it indicates that the laser sensor 3 has reached the left end of the workpiece 1 (such as Figure 5 As shown), and record the number of pulses at this time, and then move the laser sensor 3 in the opposite direction. When the data returned by the laser sensor 3 changes from a valid value to an invalid value again, it means that the laser sensor 3 has reached the right end of the workpiece 1 (as shown in FIG. Figure 5 For detailed process, see Fig.10 , and record the number of pulses at this time, so that the length L of the workpiece 1 can be calculated.

[0082] Embodiment 5

[0083] On the basis of the third or fourth embodiment, this embodiment calculates the diameter deviation T, straightness S and roundness Q of the workpiece 1 , and the calculation of these parameters is based on the actual diameter of the workpiece 1 .

[0084] The theoretical radius of workpiece 1 refers to the distance from the surface of workpiece 1 to the rotation center of workpiece 1. The theoretical diameter of workpiece 1 is twice the theoretical radius of workpiece 1. The rotation center of workpiece 1 is the point where the laser sensor 3 measures the reflection surface, that is, Figure 8 and Fig. 9 Point O in the figure is the actual diameter of workpiece 1. As the name implies, it is the diameter obtained with the actual center of workpiece 1 as the center, that is, Figure 8 and Fig. 9 Point O' in.

[0085] The actual diameter measurement steps of the workpiece 1 include:

[0086] S31: A rectangular coordinate system is established with the rotation axis O of the workpiece 1 as the origin and the line connecting the laser sensor 3 and the rotation axis O as the Y axis. The workpiece 1 is rotated N times by the rotating mechanism 5 (before each rotation, the laser sensor 3 moves upward to the initial position. After the rotation is completed and the rotating mechanism 5 exits, the laser sensor 3 moves downward to the measurement area. In other optional methods, the laser sensor 3 can also be moved along the X axis to a position that does not interfere with the rotating mechanism 5). The Nth rotation angle is θ N , for example, Figure 8 As shown, the first rotation angle of workpiece 1 is θ 1 , point P on workpiece 1 1 Rotate to the Y axis and calculate the theoretical diameter D at this time 1 , then in the rectangular coordinate system point P 1 The coordinates of 1 (x 1 ,y 1 ),in like Figure 2 As shown, the second rotation angle of workpiece 1 is θ 2 , point P on workpiece 1 2 Rotate to the Y axis and calculate the theoretical diameter D at this time 2 , then in the rectangular coordinate system point P 2 The coordinates of 2 (x 2 ,y 2 ),in By analogy, calculate the theoretical diameter D of workpiece 1 after the Nth rotation. N , and the coordinate point P under the theoretical diameter is obtained N (x N ,y N ),in Among them, P N (x N ,y N) is the coordinate of the Nth point on the surface of workpiece 1. The total rotation angle of workpiece 1 is generally within 360°, that is, (θ 1 +θ 2 +θ 3 +…+θ N )≤360°.

[0087] S32: Based on the coordinate point P in step S31 N (x N ,y N ), and use the least square method to find the actual center coordinates O'(x', y') of the workpiece 1. The least square method is a relatively mature calculation method and can be directly calculated using an existing least square method calculator.

[0088] S33: Calculate the actual diameter of workpiece 1

[0089] According to the point O' and the different points on the workpiece 1 (P 1 , P 2 , ..., P N ) coordinates to calculate the distance between the two points. The distance value is the actual radius of the workpiece 1, so that multiple sets of different actual diameter data (D′) can be obtained. 1 , D′ 2 , D′ 3 ,…,D′ N ).

[0090] The calculation formula for the straightness of workpiece 1 is:

[0091] ,

[0092] Among them, D' max is the actual diameter of workpiece 1 (D′ 1 , D′ 2 , D′ 3 ,…,D′ N ), D' min is the actual diameter of workpiece 1 (D′ 1 , D′ 2 , D′ 3 ,…,D′ N ), L is the axial length of workpiece 1.

[0093] The roundness calculation formula of workpiece 1 is:

[0094] ,

[0095] Among them, D' max is the actual diameter of workpiece 1 (D′ 1 , D′ 2 , D′3 ,…,D′ N ), D' min is the actual diameter of workpiece 1 (D′ 1 , D′ 2 , D′ 3 ,…,D′ N ) is the minimum value among .

[0096] The calculation formula for the diameter deviation of workpiece 1 is:

[0097] T=|D′-D 标 |

[0098] , where D 标 It is the standard diameter of seamless steel pipe.

[0099] like Fig.10 As shown, it is a specific operation process for using the present invention to detect the parameters of the workpiece 1. It should be noted that this process is a universal detection process and does not include step S1. Step S1 is only adjusted when the device is initially used and is not a step that needs to be performed for each workpiece 1 detection.

[0100] In this process, the system is first reset, including the laser sensor 3 and the rotating mechanism 5 are both in the initial position, and then the workpiece 1 is transported to the position of the laser sensor 3, and the diameter measurement and length measurement can be performed (see Examples 3 and 4 for specific measurement steps). After the length measurement is completed, the laser displacement sensor is moved to the left to a position that does not interfere with the rotating mechanism 5, such as the gap position between two adjacent rotating mechanisms 5, and then the second cylinder 505 moves down close to the workpiece 1 until the friction wheel 503 contacts the workpiece 1. The rotating motor 502 drives the workpiece 1 to rotate so that the workpiece 1 rotates a certain angle, and then the laser sensor 3 is used to detect data (see Step S31 in Example 5 for specific steps). When the diameter deviation T, straightness S and roundness Q of the workpiece 1 are outside the standard range, the laser sensor 3 is reset and the detection is ended. When the diameter deviation T, straightness S and roundness Q of the workpiece 1 are within the standard range, the workpiece 1 continues to be rotated and measured with the laser sensor 3. After the detection is completed, the laser sensor 3 is reset, and the conveying motor 8 is started to convey the workpiece 1 to outside the detection area.

[0101] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by terms such as “center”, “length”, “up”, “down”, “vertical”, “horizontal”, “axial” and “circumferential” are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0102] In addition, the terms "first", "second", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0103] In this specification, the schematic representation of the terms does not necessarily refer to the same embodiment. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in one or more embodiments.

[0104] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for automatically detecting geometric parameters of seamless steel pipes, characterized in that: The method adopts the following seamless steel pipe geometric parameter automatic detection device, which comprises a conveying roller (2) for conveying a workpiece (1), a laser sensor (3) for measuring distance, a photoelectric sensor (4) for controlling the motion state of the workpiece (1), and a rotating mechanism (5); the laser sensor (3) and the photoelectric sensor (4) are electrically connected to a controller; The conveying roller (2) has a V-shaped groove (201) for placing the workpiece (1); the laser sensor (3) can reciprocate along the X direction so that the laser sensor (3) measures the dimensions of different axial positions of the workpiece (1); the laser sensor (3) can also reciprocate along the Y direction so that the laser sensor (3) is directly opposite to the center of the V-shaped groove (201); the laser sensor (3) can also reciprocate along the Z direction to adjust the distance between the laser sensor (3) and the workpiece (1); the rotating mechanism (5) can be raised and lowered along the Z-axis direction so that the rotating mechanism (5) is separated from the workpiece (1) or drives the workpiece (1) to rotate; The rotating mechanism (5) comprises two rotating drive groups arranged along the length direction of the workpiece (1); The rotary drive group comprises a frame (501), a rotary motor (502) movably connected to the frame (501), and a friction wheel (503) connected to an output shaft of the rotary motor (502), wherein the friction wheel (503) is capable of contacting an outer surface of a workpiece (1) and driving the workpiece (1) to rotate; The method comprises the following steps: S1: centering the laser sensor (3); moving the laser sensor (3) along the Y direction so that the laser sensor (3) is aligned with the center of the V-shaped groove (201), and recording the distance M between the laser sensor (3) and the bottom of the V-shaped groove (201) at this time; S2: conveying the workpiece (1); conveying the workpiece (1) on the conveying roller (2), using the photoelectric sensor (4) to control the start and stop of the workpiece (1), so that the workpiece (1) is directly above the laser sensor (3), and at this time the workpiece (1) is outside the measurement range of the laser sensor (3); S3: Diameter measurement: adjust the laser sensor (3) along the Z direction so that the workpiece (1) is within the measurement range of the laser sensor (3), measure the distance B between the laser sensor (3) and the surface of the workpiece (1) at this time, and calculate the theoretical diameter D and actual diameter D of the workpiece (1). ′ N ; S4: laser sensor (3) reset: move the laser sensor (3) along the Z direction so that the workpiece (1) is located outside the measurement range of the laser sensor (3); The theoretical diameter D of the workpiece (1) is: ， Wherein, f is the frequency of the pulse signal emitted by the controller, k1 is the ratio of the pulse equivalent of the driving module driving the laser sensor (3) to move along the Z direction to the moving distance of the laser sensor (3) driven by the driving module; A1 is the number of pulses in the register of the controller after step S1; A2 is the number of pulses in the register of the controller after step S3; The actual diameter measurement step of the workpiece (1) in step S3 includes: S31: A rectangular coordinate system is established with the rotation axis O of the workpiece (1) as the origin and the line connecting the laser sensor (3) and the rotation axis O as the Y axis. The workpiece (1) is rotated N times by the rotating mechanism (5). The Nth rotation angle θ N , calculate the theoretical diameter D of the workpiece (1) after the Nth rotation N , and the coordinate point P under the theoretical diameter is obtained N (x N ,y N ),in Among them, P N (x N ,y N ) is the coordinate of the Nth point on the surface of the workpiece (1); S32: Based on the coordinate point P in step S31 N (x N ,y N ), use the least squares method to find the actual center coordinates O of the workpiece (1) ’ (x ’ ,y ’ ); S33: Calculate the actual diameter of the workpiece (1) 2. The method for automatically detecting geometric parameters of seamless steel pipes according to claim 1, characterized in that: It also includes an X-axis drive module, a Y-axis drive module and a Z-axis drive module which are sequentially connected to form a three-stage drive module, wherein the laser sensor (3) is connected to the last-stage drive module; the X-axis drive module, the Y-axis drive module and the Z-axis drive module are all electrically connected to a controller; The X-axis drive module drives the laser sensor (3) to reciprocate along the axial direction of the workpiece (1); the Y-axis drive module drives the laser sensor (3) to move perpendicularly to the axial direction of the workpiece (1) in a horizontal plane; and the Z-axis drive module drives the laser sensor (3) to move perpendicularly to the axial direction of the workpiece (1) in a vertical plane.

3. The method for automatically detecting geometric parameters of seamless steel pipes according to claim 1, characterized in that: It also comprises a conveying motor (8), a plurality of conveying rollers (2) are arranged along the axial direction of the workpiece (1), and the conveying motor (8) is drivingly connected to one or more of the conveying rollers (2).

4. The method for automatically detecting geometric parameters of seamless steel pipes according to claim 1, characterized in that: Step S3 also includes measuring the length of the workpiece (1). First, the laser sensor (3) is moved along the X direction to one axial end of the workpiece (1), and the number of pulses in the register is recorded as C1. Then, the laser sensor (3) is moved along the X direction to the other axial end of the workpiece (1), and the number of pulses in the register is recorded as C2. Then, the length L of the workpiece (1) is: L=k2*(C2-C1)*f, Wherein, f is the frequency of the pulse signal emitted by the controller, and k2 is the ratio of the pulse equivalent of the driving module driving the laser sensor (3) to move along the X direction to the moving distance of the laser sensor (3) driven by the driving module.

5. The method for automatically detecting geometric parameters of seamless steel pipes according to claim 1, characterized in that: The straightness of the workpiece (1) is: , Among them, D ’ max is the actual diameter (D) of the workpiece (1) ′ 1, D ′ 2, D ′ 3, ..., D ′ N ), D ’ min is the actual diameter (D) of the workpiece (1) ′ 1, D ′ 2, D ′ 3, ..., D ′ N ), L is the axial length of the workpiece (1).

6. The method for automatically detecting geometric parameters of seamless steel pipes according to claim 1, characterized in that: The roundness of the workpiece (1) is: , Among them, D ’ max is the actual diameter (D) of the workpiece (1) ′ 1, D ′ 2, D ′ 3, ..., D ′ N ), D ’ min is the actual diameter (D) of the workpiece (1) ′ 1, D ′ 2, D ′ 3, ..., D ′ N ) is the minimum value among .

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