A method for cooperation between clamping and transverse movement of a steel pipe galvanizing production line
By combining servo motor clusters and a normal distribution model, the attitude of the steel pipe's center of gravity is adjusted in real time, solving the problem of coordinated control between the clamping and lateral movement systems in the steel pipe galvanizing production line, and achieving high-precision steel pipe positioning and stable coating quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TIANJIN ZHONGCHI IND CO LTD
- Filing Date
- 2026-03-26
- Publication Date
- 2026-06-19
Smart Images
Figure CN122235616A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of steel pipe galvanizing technology, and in particular relates to a method for coordinated clamping and transverse movement in a steel pipe galvanizing production line. Background Technology
[0002] In continuous hot-dip galvanizing production lines, the stable transport of steel pipes is crucial for ensuring coating quality. The clamping system extracts and lifts the galvanized steel pipes from the zinc pot, while the traversing system receives the pipes and horizontally transports them to subsequent stages such as internal blowing. Their coordination constitutes a key link in the production process. Currently, this process is generally controlled sequentially by a programmable logic controller (PLC), relying on preset timing and position commands to drive the clamping device and the traversing machine's ordinary motors or hydraulic cylinders. However, this type of control system has significant limitations: due to the lack of high-precision perception of the steel pipe's real-time posture and stress state, it is essentially an "open-loop" or "semi-open-loop" programmed operation. This results in the system's inability to dynamically respond to minute positional shifts and tilts during clamping and placement, leading to uncertain random errors in the initial state of the steel pipe on the traversing machine. These initial errors are amplified during subsequent high-speed transport, becoming a major cause of steel pipe vibration, positioning inaccuracies, and even uneven coating in the final internal blowing process. Summary of the Invention
[0003] In view of this, the present invention aims to propose a clamping and transverse movement coordination method for a steel pipe galvanizing production line, so as to achieve precise centering of the steel pipe on the transverse movement machine and ensure the stability and high quality of the subsequent internal blowing process.
[0004] To achieve the above objectives, the technical solution of the present invention is implemented as follows:
[0005] A method for coordinated clamping and lateral movement in a steel pipe galvanizing production line.
[0006] Furthermore, the front rollers of the transverse transfer machine are driven by a cluster of servo motors, while the rear rollers are driven by ordinary motors. After the clamping device moves the steel pipe onto the transverse transfer machine, the rollers of the transverse transfer machine are first driven to rotate by a cluster of servo motors. The cluster of servo motors consists of two servo motors on the left and right as a group, with multiple groups connected in series. Based on the real-time data of each servo motor, the output shaft of the servo motor acting on the steel pipe is oriented and adjusted, forcing the center of gravity of the steel pipe to coincide with the mechanical center of the transverse transfer machine.
[0007] The process of adjusting each servo motor in a directional manner to correct the posture of the steel pipe's center of gravity includes the following steps:
[0008] S1. All servo motors pre-rotate simultaneously. After the rotation is completed, record the difference in maximum torque of each group of servo motors arranged on the left and right sides during the rotation process.
[0009] S2. Based on the distribution of torque differences among the servo motors, find the group of servo motors that is in contact with the middle of the steel pipe. Using this group of torque motors as the center, select an equal number of servo motor groups forward and backward. Continuously jog the servo motors on the side with the larger torque for these servo motor groups and record the torque difference of these servo motor groups during the jogging process.
[0010] S3. After the maximum torque difference of all servo motor groups is less than the set threshold, stop the steel pipe center of gravity correction, and simultaneously drive all servo motors and ordinary motors at the same speed to move the steel pipe to the inner blowing area for the next process.
[0011] Furthermore, in S1, the pre-rotation adopts a low-speed short-time rotation of all servo motors. It is stipulated that the forward rotation of the servo motor is the forward direction of the steel pipe, and the backward rotation is the backward direction of the steel pipe. The backward direction is towards the clamping device. The torque difference is the left servo motor minus the right servo motor. The rotation direction is first forward and then backward. During the reversal, it stops for a period of time, and the speed and angle of the forward and backward rotation of the servo motor are the same.
[0012] The maximum torque difference of each group of servo motors during the two rotations is set as the difference of the maximum torque of that group of servo motors.
[0013] Furthermore, S2 includes:
[0014] S21. It is stipulated that the forward rotation of the servo motor is positive torque and the backward rotation is negative torque. When the difference in forward or backward rotation torque of most servo motor groups in front of the servo motor group in the middle of the steel pipe is positive, and the difference in forward or backward rotation torque of most servo motor groups behind is negative, the steel pipe is considered to be tilted to the left and rotated S22.
[0015] When the torque difference between the forward and backward rotation of most servo motors in front of the servo motor group in the middle of the steel pipe is negative, and the torque difference between the forward and backward rotation of most servo motors behind is positive, the steel pipe is considered to be tilted to the right and rotates to S23.
[0016] S22. The servo motor group in front of the servo motor group in the middle of the steel pipe moves forward at a low speed continuously, and the servo motor group behind moves backward at a low speed continuously, and the number of jogs is recorded.
[0017] S23. The servo motor group in front of the servo motor group in the middle of the steel pipe moves backward at a low speed continuously, and the servo motor group behind it moves forward at a low speed continuously, and the number of jogs is recorded.
[0018] Furthermore, in S3, the maximum torque difference of the servo motor group is the static torque difference. When the absolute value of the static torque difference is less than the set threshold or the number of recorded jogs exceeds the set number of adjustments, the steel pipe is considered to be aligned and the correction of the steel pipe's center of gravity is stopped.
[0019] Furthermore, a support vector machine is used to record and identify the jogging speed, angle, torque difference threshold, and jogging number threshold of steel pipes of different lengths and diameters. The centering data with different static torque difference absolute values less than the set threshold are used as input vectors, and the jogging number when the static torque difference absolute value is less than the set threshold is used as labels to train the support vector machine.
[0020] Furthermore, in S2, a normal distribution model is used to arrange the torque differences of all servo motor groups. Each group of servo motors is arranged in front and behind as the horizontal axis and the torque difference as the vertical axis to fit a normal distribution curve. The peak interval of the normal distribution curve is extracted, and the middle coordinate of the interval is taken as the group of servo motors that are in contact with the middle of the steel pipe.
[0021] Furthermore, the normal distribution parameters of steel pipes of different lengths and diameters are recorded and identified using a support vector machine, and the support vector machine is trained using actual torque values and the position of the middle part of the steel pipe.
[0022] Its normal distribution parameters include the mean:
[0023] ;
[0024] In the formula, Let be the probability density function of the normal distribution. The horizontal axis represents the servo motor assembly. The mean of a normal distribution is . The standard deviation of the normal distribution
[0025] Its intermediate coordinate positioning includes:
[0026] ;
[0027] In the formula, The horizontal coordinate of the servo motor in the middle of the steel pipe is [value]. It is an adjustable coefficient.
[0028] Furthermore, an electronic device includes a processor and a memory communicatively connected to the processor and used to store processor-executable instructions, the processor being used to execute the aforementioned clamping and lateral movement coordinated method for a steel pipe galvanizing production line.
[0029] Furthermore, a server includes at least one processor and a memory communicatively connected to the processor, the memory storing instructions executable by the at least one processor, the instructions being executed by the processor to cause the at least one processor to perform the aforementioned clamping and lateral movement coordinated method for a steel pipe galvanizing production line.
[0030] Furthermore, a computer-readable storage medium stores a computer program, which, when executed by a processor, implements the aforementioned clamping and lateral movement coordinated method for a steel pipe galvanizing production line.
[0031] Compared with the prior art, the clamping and lateral movement coordinated method for a steel pipe galvanizing production line described in this invention has the following advantages:
[0032] (1) The clamping and transverse movement coordination method of the steel pipe galvanizing production line described in this invention drives the servo motor cluster to rotate bidirectionally and collect torque data. It uses a normal distribution model to accurately fit the center of gravity position and attitude of the steel pipe. Through the bidirectional torque difference and the normal distribution model, the system can effectively filter noise signals caused by mechanical vibration and instantaneous slippage, and transform discrete force signals into continuous and stable center of gravity position estimates. The positioning accuracy is far superior to the rough method that relies on the maximum value of a single point or human observation.
[0033] (2) The clamping and transverse movement coordination method of the steel pipe galvanizing production line described in this invention adopts a hybrid architecture of "front-end servo motor cluster drive + rear-end ordinary motor drive". Only the front-end key area is equipped with high-precision servo motors that can provide feedback torque to undertake the task of "sensing and fine adjustment". The rear-end uses ordinary motors to be responsible for "stable conveying", which reduces the total hardware cost of the system and the complexity of subsequent maintenance.
[0034] (3) The clamping and transverse movement coordination method of the steel pipe galvanizing production line described in this invention uses the successful centering data of steel pipes of different specifications as input vectors and the centering effect (such as the number of jogs) as output labels to train a support vector machine model. When a new specification of steel pipe is put into production, the support vector machine model can predict and recommend a set of optimal initial jog parameters and thresholds based on historical data, so that the system can quickly approach the optimal correction state. Attached Figure Description
[0035] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:
[0036] Figure 1 This is a schematic diagram of the clamping and lateral movement coordination method for a steel pipe galvanizing production line according to an embodiment of the present invention;
[0037] Figure 2 This is a schematic diagram illustrating the left tilt correction according to an embodiment of the present invention;
[0038] Figure 3 This is a schematic diagram illustrating the right tilt correction according to an embodiment of the present invention. Detailed Implementation
[0039] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.
[0040] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.
[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0042] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0043] A method for coordinated clamping and traversing in a steel pipe galvanizing production line is based on a normal distribution model and real-time torque feedback from servo motors. When the clamp moves the steel pipe to the traversing machine, the method intelligently identifies and positions the steel pipe's center of gravity posture based on the force and position information of the servo motor cluster. It then adjusts the steel pipe's posture so that its concentric axis coincides with a specific and unique mechanical position on the traversing machine, using this position and posture as a reference for subsequent internal blowing processes. The specific hardware components include: the front rollers of the traversing machine are driven by a cluster of servo motors, while the rear rollers are driven by ordinary motors. The steel pipe's posture is corrected and centered by the servo motor cluster at the front, and then it is moved and conveyed at high speed by the ordinary motors at the rear, thus saving hardware costs. After the clamping device's grippers move the steel pipe onto the traversing machine, the servo motor cluster first drives the traversing machine's rollers to rotate, such as... Figures 2-3As shown, the servo motor cluster consists of multiple groups of two servo motors connected in series, with each roller driven by a single independent servo motor. Based on real-time data from each servo motor, the output shafts of the servo motors acting on the steel pipe are oriented and adjusted, forcing the steel pipe's center of gravity to coincide with the mechanical center of the transverse conveyor. The process of oriented adjustment of each servo motor to correct the steel pipe's center of gravity posture includes the following steps:
[0044] S1. After the steel pipe is in place and stabilized by the transverse transfer machine, all servo motors pre-rotate at the same time. After the rotation is completed, record the difference in maximum torque of each group of servo motors arranged on the left and right sides during the rotation process.
[0045] S2. Based on the distribution of torque differences among the servo motors, find the group of servo motors that is in contact with the middle of the steel pipe. Using this group of torque motors as the center, select an equal number of servo motor groups forward and backward. Continuously jog the servo motors on the side with the larger torque for these servo motor groups and record the torque difference of these servo motor groups during the jogging process.
[0046] S3. After the maximum torque difference of all servo motor groups is less than the set threshold, stop the steel pipe center of gravity correction, and simultaneously drive all servo motors and ordinary motors at the same speed to move the steel pipe to the inner blowing area for the next process.
[0047] Specifically, in S1, the pre-rotation uses low-speed short-time rotation of all servo motors. The forward rotation of the servo motor is defined as the forward direction of the steel pipe, and the backward rotation is defined as the backward direction of the steel pipe. The backward direction is towards the clamping device. The torque difference is the difference between the left servo motor and the right servo motor. The rotation direction is first forward and then backward. During the reversal, there is a pause for a period of time. The speed and angle of the forward and backward rotation of the servo motors are the same. The maximum torque difference of each group of servo motors during the two rotations is set as the difference of the maximum torque of the group of servo motors, and the maximum torque difference is expressed as an absolute value.
[0048] Specific examples Figure 1 As shown, S2 includes:
[0049] S21. It is stipulated that the forward rotation of the servo motor is positive torque and the backward rotation is negative torque. When the difference in forward or backward rotation torque of most servo motor groups in front of the servo motor group in the middle of the steel pipe is positive, and the difference in forward or backward rotation torque of most servo motor groups behind is negative, the steel pipe is considered to be tilted to the left and rotated S22.
[0050] When the torque difference between the forward and backward rotation of most servo motors in front of the servo motor group in the middle of the steel pipe is negative, and the torque difference between the forward and backward rotation of most servo motors behind is positive, the steel pipe is considered to be tilted to the right and rotates to S23.
[0051] S22. The servo motor group in front of the servo motor group in the middle of the steel pipe moves forward at a low speed continuously, and the servo motor group behind it moves backward at a low speed continuously. The number of movements is recorded. Figure 2 As shown, according to the sum of the planar forces, the total force at the upper end of the steel pipe is to the right, and the total force at the lower end is to the left. As the roller rotates, it drives the steel pipe to return to its correct position.
[0052] S23. The servo motor group in front of the servo motor group in the middle of the steel pipe moves backward at a low speed continuously, and the servo motor group behind it moves forward at a low speed continuously, and the number of movements is recorded. Figure 3 As shown, according to the sum of the planar forces, the total force at the upper end of the steel pipe is to the left, and the total force at the lower end is to the right. As the roller rotates, it drives the steel pipe to return to its correct position.
[0053] Optionally, in S3, the maximum torque difference of the servo motor group is the static torque difference, that is, the stable torque difference after the steel pipe stops moving. When the absolute value of the static torque difference is less than the set threshold or the number of recorded jogs exceeds the set number of adjustments, the steel pipe is considered to be aligned and the correction of the steel pipe's center of gravity is stopped. The advantage is that introducing the number of jogs as a judgment condition can prevent the steel pipe alignment action from failing to converge due to overcorrection and oscillation correction.
[0054] Optionally, a support vector machine is used to record and identify the jogging speed, angle, torque difference threshold, and jogging number threshold of steel pipes of different lengths and diameters. The centering data with different static torque difference absolute values less than the set threshold are used as input vectors, and the jogging number when the static torque difference absolute value is less than the set threshold is used as labels to train the support vector machine.
[0055] Specifically, when all rollers (or servo motors) measure the supporting force on the steel pipe in real time, the force distribution along the length of the entire steel pipe will theoretically exhibit a normal distribution with the center of gravity (the very middle) of the steel pipe as the axis of symmetry. The advantage of using a probabilistic statistical model to determine the steel pipe's attitude in this application is that it can transform discrete, easily disturbed servo motor torque data into a smooth, continuous probability distribution curve, thereby stably and noise-resistantly identifying the theoretical center point of the steel pipe's force, overcoming the random errors of simply finding the "maximum torque point." Meanwhile, torque signals in industrial settings are susceptible to random interference such as mechanical vibration and instantaneous slippage, exhibiting spikes and fluctuations. Normal distribution fitting, through maximum likelihood estimation, avoids getting bogged down in individual outlier data points, instead finding the smoothest curve that best represents the overall trend of all data. At the decision-making level, it provides quantifiable "confidence intervals" and "state assessments," quantifying the stability of the steel pipe's attitude.
[0056] Specifically, in S2, a normal distribution model is used to arrange the torque differences of all servo motor groups. Each group of servo motors is arranged in front and behind as the horizontal axis, and the torque difference is used as the vertical axis to fit a normal distribution curve. The peak interval of the normal distribution curve is extracted, and the middle coordinate of the interval is taken as the group of servo motors that are in contact with the middle of the steel pipe.
[0057] Specifically, the normal distribution parameters of steel pipes of different lengths and diameters are recorded and identified using a support vector machine, and the support vector machine is trained using the actual torque value and the position of the middle part of the steel pipe.
[0058] Its normal distribution parameters include the mean:
[0059] ;
[0060] In the formula, Let be the probability density function of the normal distribution. The horizontal axis represents the servo motor assembly. The mean of a normal distribution is . The standard deviation of the normal distribution
[0061] Its intermediate coordinate positioning includes:
[0062] ;
[0063] In the formula, The horizontal coordinate of the servo motor in the middle of the steel pipe is [value]. It is an adjustable coefficient.
[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A method for coordinated clamping and lateral movement in a steel pipe galvanizing production line, characterized in that: The front rollers of the transverse transfer machine are driven by a cluster of servo motors, while the rear rollers are driven by ordinary motors. After the clamping device moves the steel pipe onto the transverse transfer machine, the rollers of the transverse transfer machine are first driven to rotate by a cluster of servo motors. The cluster of servo motors consists of two servo motors on the left and right as a group, with multiple groups connected in series. Based on the real-time data of each servo motor, the output shaft of the servo motor acting on the steel pipe is adjusted to force the center of gravity of the steel pipe to coincide with the mechanical center of the transverse transfer machine. The process of adjusting each servo motor in a directional manner to correct the posture of the steel pipe's center of gravity includes the following steps: S1. All servo motors pre-rotate simultaneously. After the rotation is completed, record the difference in maximum torque of each group of servo motors arranged on the left and right sides during the rotation process. S2. Based on the distribution of torque differences among the servo motors, find the group of servo motors that is in contact with the middle of the steel pipe. Using this group of torque motors as the center, select an equal number of servo motor groups forward and backward. Continuously jog the servo motors on the side with the larger torque for these servo motor groups and record the torque difference of these servo motor groups during the jogging process. S3. After the maximum torque difference of all servo motor groups is less than the set threshold, stop the steel pipe center of gravity correction, and simultaneously drive all servo motors and ordinary motors at the same speed to move the steel pipe to the inner blowing area for the next process.
2. The clamping and lateral movement coordinated method for a steel pipe galvanizing production line according to claim 1, characterized in that: In S1, the pre-rotation adopts a low-speed short-time rotation of all servo motors. It is specified that the forward rotation of the servo motor is the forward direction of the steel pipe, and the backward rotation is the backward direction of the steel pipe. The backward direction is towards the clamping device. The torque difference is the left servo motor minus the right servo motor. The rotation direction is first forward and then backward. During the reversal, it stops for a period of time, and the speed and angle of the forward and backward rotation of the servo motor are the same. The maximum torque difference of each group of servo motors during the two rotations is set as the difference of the maximum torque of that group of servo motors.
3. The clamping and lateral movement coordinated method for a steel pipe galvanizing production line according to claim 1, characterized in that: The S2 includes: S21. It is stipulated that the forward rotation of the servo motor is positive torque and the backward rotation is negative torque. When the difference in forward or backward rotation torque of most servo motor groups in front of the servo motor group in the middle of the steel pipe is positive, and the difference in forward or backward rotation torque of most servo motor groups behind is negative, the steel pipe is considered to be tilted to the left and rotated S22. When the torque difference between the forward and backward rotation of most servo motors in front of the servo motor group in the middle of the steel pipe is negative, and the torque difference between the forward and backward rotation of most servo motors behind is positive, the steel pipe is considered to be tilted to the right and rotates to S23. S22. The servo motor group in front of the servo motor group in the middle of the steel pipe moves forward at a low speed continuously, and the servo motor group behind moves backward at a low speed continuously, and the number of jogs is recorded. S23. The servo motor group in front of the servo motor group in the middle of the steel pipe moves backward at a low speed continuously, and the servo motor group behind it moves forward at a low speed continuously, and the number of jogs is recorded.
4. The clamping and lateral movement coordination method for a steel pipe galvanizing production line according to claim 3, characterized in that: In S3, the maximum torque difference of the servo motor group is the static torque difference. When the absolute value of the static torque difference is less than the set threshold or the number of recorded jogs exceeds the set number of adjustments, the steel pipe is considered to be aligned and the correction of the steel pipe's center of gravity is stopped.
5. The clamping and lateral movement coordinated method for a steel pipe galvanizing production line according to claim 4, characterized in that: Support vector machines are used to record and identify the jogging speed, angle, torque difference threshold, and jogging number threshold of steel pipes of different lengths and diameters. The centering data with different static torque difference absolute values less than the set threshold are used as input vectors, and the jogging number when the static torque difference absolute value is less than the set threshold is used as labels to train the support vector machine.
6. The clamping and lateral movement coordinated method for a steel pipe galvanizing production line according to claim 4, characterized in that: In S2, a normal distribution model is used to arrange the torque differences of all servo motor groups. Each group of servo motors is arranged in front and behind as the horizontal axis and the torque difference is used as the vertical axis to fit a normal distribution curve. The peak interval of the normal distribution curve is extracted, and the middle coordinate of the interval is taken as the group of servo motors that are in contact with the middle of the steel pipe.
7. The clamping and lateral movement coordinated method for a steel pipe galvanizing production line according to claim 1, characterized in that: Support vector machines are used to record and identify the normal distribution parameters of steel pipes of different lengths and diameters, and the support vector machines are trained using actual torque values and the position of the middle part of the steel pipes. Its normal distribution parameters include the mean: ； In the formula, Let be the probability density function of the normal distribution. The horizontal axis represents the servo motor assembly. The mean of a normal distribution is . The standard deviation of the normal distribution Its intermediate coordinate positioning includes: ； In the formula, The horizontal coordinate of the servo motor in the middle of the steel pipe is [value]. It is an adjustable coefficient.
8. An electronic device comprising a processor and a memory communicatively connected to the processor and used for storing processor-executable instructions, characterized in that: The processor is used to execute the clamping and transverse movement coordinated method for a steel pipe galvanizing production line as described in any one of claims 1-7.
9. A server, characterized in that: It includes at least one processor and a memory communicatively connected to the processor, the memory storing instructions executable by the at least one processor, the instructions being executed by the processor to cause the at least one processor to perform a clamping and lateral movement coordinated method for a steel pipe galvanizing production line as described in any one of claims 1-7.
10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by the processor, it implements the clamping and lateral movement coordinated method for a steel pipe galvanizing production line as described in any one of claims 1-7.