A diameter detection method and device suitable for cast pipe production line

Abstract

The present invention provides a diameter detection method suitable for a cast pipe production line, comprising the following steps: A. measuring the height L1 from the lower plane of the laser sensor to the ground; B. measuring the height L2 from the contact roller of the magnetic cylinder to the ground when it is not extended; C. calculating L3=L1-L2 and storing it in a PLC controller; D. after the laser sensor detects the cast pipe, it is judged that there is a pipe; E. reading the value of the laser sensor to obtain the height L from the laser sensor to the upper cut surface of the cast pipe. u1 ; F. Read the encoder value to get the extension length L of the magnetic cylinder d1 At this time, the diameter of the cast pipe is L x1 =L3-L u1 ‑L d1 The invention has a simple structure, is easy to disassemble and assemble, and is easy to maintain; it can simultaneously detect the upper and lower horizontal sections of the cast pipe body, and the detection accuracy is not affected when the cast pipe position changes up and down or rotates and jumps; it has a large detectable cast pipe range and is suitable for diameter detection of cast pipes or steel pipes of all current specifications.

Description

Technical Field

[0001] The invention belongs to the technical field of cast pipe production, and in particular relates to a diameter detection method and device suitable for a cast pipe production line. Background Art

[0002] At present, in the cast pipe production process, stable and rapid detection of cast pipe diameter is a prerequisite for the automatic operation of the cast pipe production line. With the improvement of equipment level, the cast pipe production line now basically realizes automatic operation, but in the actual production process, the pipe diameter parameter often becomes the "bottleneck" of the automatic operation of the equipment. In the current production lines, the main methods for detecting the diameter of cast pipes are: 1. Use a single laser to illuminate the highest point of the cast pipe body from top to bottom, and then compare the feedback value with the known pipe diameter feedback value to obtain the diameter of the cast pipe to be measured. The main disadvantages of this method are: 1. Poor detection accuracy. When the diameters of cast pipes are adjacent, incorrect comparison results are often obtained; 2. Since it uses "empirical" values, when the height of the target to be measured changes (such as adjustment of the spacing between the support wheels, etc.), all the set parameters need to be re-entered; 3. When the cast pipe rotates, the cast pipe to be measured may jump up and down, and the accuracy cannot be guaranteed by single-sided laser detection; 2. The upper and lower lasers are used to detect and calculate the pipe diameter. The disadvantages of this method are: 1. The laser sensor is installed from bottom to top, the lens is easy to get dirty, and maintenance is cumbersome; 2. Due to the small space on the lower end face of the cast pipe, a high-precision small-range laser must be used, which is expensive; 3. According to a device for measuring the diameter of a steel pipe using a laser displacement sensor disclosed in patent CN104359413A, multiple groups of laser detection and calculation are used, but the disadvantage of this method is that due to the large change in the curvature of large-diameter cast pipes, the device is difficult to detect large-diameter cast pipes. Summary of the invention

[0003] The purpose of the present invention is to solve the shortcomings existing in the prior art and to provide a diameter detection method and device suitable for a cast pipe production line with accurate measurement.

[0004] The technical solution adopted by the present invention is: a diameter detection method suitable for a cast pipe production line, comprising the following steps:

[0005] A. Measure the height L1 from the lower plane of the laser sensor to the ground, and store L1 as known data in the PLC controller;

[0006] B. Measure the height L2 from the contact roller to the ground of the magnetic cylinder of the cast pipe lower section detection device when it is not extended. L2 is stored in the PLC controller as known data;

[0007] C. Calculate L3=L1-L2 and store it in the PLC controller;

[0008] D. When the casting pipe is sent from the previous station to the supporting wheel frame, the laser sensor detects the casting pipe and determines that there is a pipe; the magnetic cylinder extends and the cylinder sensor is triggered, which means that the pipe is abnormal. If the cylinder sensor is not triggered, it is determined that the pipe is normal.

[0009] E. Read the laser sensor value to obtain the height L from the laser sensor to the upper section of the cast pipe u1 , stored in the PLC controller;

[0010] F. Read the encoder value to get the extension length L of the magnetic cylinder d1 , stored in the PLC controller, the diameter of the casting pipe is L x1 =L3-L u1 -L d1 ;

[0011] G. Repeat the above steps EF to read the array data, add and average the results of each group of data to get the average value, which is used as the final calculation result and sent to the production line. The test is completed;

[0012] L x = (L x1 + L x2 +……+ L xn ) / n, where L xn Indicates the result obtained by the nth detection.

[0013] A diameter detection device suitable for a cast pipe production line comprises a roller frame, a limit block, a cast pipe upper section detection device, a cast pipe lower section detection device, a PLC controller and a cast pipe, wherein the cast pipe lower section detection device is located between the roller frame and the limit block; the cast pipe upper section detection device comprises a bracket and a laser sensor, wherein the laser sensor is fixed to the end of the bracket; the cast pipe lower section detection device comprises a magnetic cylinder, a contact roller, an encoder, an upper connecting rod and a lower connecting rod, wherein the magnetic cylinder is vertically fixed on the ground by means of a base, wherein the contact roller is fixed to the end of the piston rod of the magnetic cylinder by means of a roller seat, wherein one end of the upper connecting rod is hinged to the roller seat and the other end is connected to the encoder, and one end of the lower connecting rod is hinged to the base and the other end is connected to the encoder; a magnetic cylinder sensor is also arranged on the outer side of the magnetic cylinder; the center of the laser sensor, the center of the cast pipe and the center of the contact roller correspond vertically, and the laser sensor, the limit block, the magnetic cylinder, the contact roller, the encoder and the magnetic cylinder sensor are all electrically connected to the PLC controller.

[0014] The laser sensor is provided with a protective cover, and the protective cover is fixed on the bracket.

[0015] The beneficial effects obtained by the present invention are as follows: the present invention has a simple structure, is easy to disassemble and assemble, and is easy to maintain; the upper and lower horizontal sections of the cast pipe body can be detected simultaneously, wherein the upper side adopts laser detection and the lower side adopts contact detection, and when the position of the cast pipe changes up and down or rotates and jumps, the detection accuracy is not affected; the detectable cast pipe range is large, and it is suitable for the diameter detection of cast pipes or steel pipes of all current specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a control flow diagram of the detection method of the present invention;

[0017] Figure 2 It is a schematic diagram of the structure of the device of the present invention;

[0018] Figure 3 It is a schematic structural diagram of the casting pipe lower cut surface detection device of the present invention;

[0019] Figure 4 It is the formula diagram of the detection method of the present invention;

[0020] Among them, 1 represents the cast pipe, 2 represents the bracket, 3 represents the protective cover, 4 represents the laser sensor, 5 represents the limit block, 6 represents the base, 7 represents the magnetic cylinder, 8 represents the contact roller, 9 represents the encoder, 10 represents the magnetic cylinder sensor, 11 represents the upper connecting rod, 12 represents the lower connecting rod, and 13 represents the roller frame. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0022] like Figure 1 , 4 As shown, a diameter detection method suitable for a cast pipe production line includes the following steps: A. measuring the height L1 from the lower plane of the laser sensor 4 to the ground, and L1 is stored in the PLC controller as known data;

[0023] B. Measure the height L2 from the contact roller 8 of the magnetic cylinder 7 of the casting pipe lower section detection device to the ground when it is not extended. L2 is stored in the PLC controller as known data;

[0024] C. Calculate L3=L1-L2 and store it in the PLC controller;

[0025] D. When the casting pipe 1 is delivered to the supporting wheel frame 13 from the previous station, the laser sensor 4 detects the casting pipe 1 and determines that there is a pipe; the magnetic cylinder 7 extends and the cylinder sensor 10 is triggered, and it is determined that the pipe is abnormal; if the cylinder sensor 10 is not triggered, it is determined that the pipe is normal;

[0026] E. Read the value of laser sensor 4 to obtain the height L from the laser sensor 4 to the upper section of the casting tube 1 u1 , stored in the PLC controller;

[0027] F. Read the value of encoder 9 to obtain the extension length L of magnetic cylinder 7 d1 , stored in the PLC controller, the diameter of the casting pipe 1 is L x1 =L3-L u1 -L d1 ;

[0028] G. Repeat the above steps EF to read the array data, add and average the results of each group of data to get the average value, which is used as the final calculation result and sent to the production line. The test is completed;

[0029] L x = (L x1 + L x2 +……+ L xn ) / n, where L xn Indicates the result obtained by the nth detection.

[0030] like Figure 2 , 3 As shown, a diameter detection device suitable for a cast pipe production line includes a roller support 13, a stop block 5, a cast pipe upper section detection device, a cast pipe lower section detection device, a PLC controller and a cast pipe 1, wherein the cast pipe lower section detection device is located between the roller support 13 and the stop block 5; the cast pipe upper section detection device includes a bracket 2 and a laser sensor 4, wherein the laser sensor 4 is fixed to the end of the bracket 2; the cast pipe lower section detection device includes a magnetic cylinder 7, a contact roller 8, an encoder 9, an upper connecting rod 11 and a lower connecting rod 12, wherein the magnetic cylinder 7 is vertically fixed to the ground by means of a base 6 On the surface, the contact roller 8 is fixed to the piston rod end of the magnetic cylinder 7 by means of a roller seat, one end of the upper connecting rod 11 is hinged to the roller seat and the other end is connected to the encoder 9, one end of the lower connecting rod 12 is hinged to the base 6 and the other end is connected to the encoder 9; a magnetic cylinder sensor 10 is also provided on the outside of the magnetic cylinder 7; the center of the laser sensor 4, the center of the casting pipe 1 and the center of the contact roller 8 are vertically corresponding, and the laser sensor 4, the limit block 5, the magnetic cylinder 7, the contact roller 8, the encoder 9 and the magnetic cylinder sensor 10 are all electrically connected to the PLC controller. A protective cover 3 is provided on the laser sensor 4, and the protective cover 3 is fixed on the bracket 2.

[0031] The PLC controller of the present invention includes a small circuit breaker, a DC power supply, a programmable logic device PLC, an intermediate relay, a solenoid valve and a pneumatic triplex; the PLC includes a CPU and an IO module. The laser sensor 4 in the upper section detection device is connected to the analog module; the encoder 9 of the lower section detection device enters the PLC according to the interface form; the magnetic cylinder sensor 10 is connected to the digital input module; the intermediate relay is controlled by the digital output module, and its contacts are connected to the solenoid valve to control the extension / retraction of the magnetic cylinder 7.

[0032] During specific implementation: the magnetic cylinder 7 is inflated and extends upward, and the magnetic cylinder 7 is deflated and retracted downward; the contact roller 8 moves up and down with the magnetic cylinder 7, and when it contacts the casting pipe 1, it rotates along with the casting pipe 1; when the cylinder extends / retracts, the upper connecting rod 11 and the lower connecting rod 12 make a crank arm reciprocating motion; the encoder 9 is installed at the node of the upper connecting rod 11 and the lower connecting rod 12 through a coupling, and its outer shell is fixed on the lower connecting rod 12. When the magnetic cylinder 7 extends / retracts, the encoder 9 rotates accordingly to collect values.

[0033] When the device is installed, follow the steps below to perform the measurement:

[0034] A. Measure the height L1 from the lower plane of the laser sensor 4 to the ground, and L1 is stored in the PLC controller as known data; B. Measure the height L2 from the contact roller 8 of the magnetic cylinder 7 of the casting pipe lower section detection device to the ground when it is not extended, and L2 is stored in the PLC controller as known data;

[0035] C. Calculate L3=L1-L2 and store it in the PLC controller; D. When the casting pipe 1 is sent from the previous station to the supporting wheel frame 13, the laser sensor 4 is first used as a pipe detection element. After detecting the casting pipe 1, it is judged that there is a pipe; the magnetic cylinder 7 is extended, and the cylinder sensor 10 is triggered, then it is judged that the incoming pipe is abnormal. If the cylinder sensor 10 is not triggered (at the same time, the sensor signal disappears when it is retracted), then it is judged that the incoming pipe is normal; E. Read the value of the laser sensor 4 to obtain the height Lu1 of the section from the laser sensor 4 to the casting pipe 1, and store it in the PLC controller; F. Read the value of the encoder 9 to obtain the extension length L of the magnetic cylinder 7 d1 , stored in the PLC controller, the diameter of the casting pipe 1 is L x1 =L3-L u1 -L d1 ; G. Repeat the above steps EF, read the array data, add and average the results of each group of data, and get the average value. This average value is used as the final calculation result and sent to the production line. The test is completed; L x = (L x1 + L x2 +……+ L xn ) / n, where L xnIndicates the result obtained by the nth detection.

[0036] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A diameter detection method suitable for a cast pipe production line, characterized in that: The following steps are involved: A. Measure the height L1 from the lower plane of the laser sensor (4) to the ground, and store L1 as known data in the PLC controller; B. measuring the height L2 from the contact roller (8) of the magnetic cylinder (7) of the casting pipe lower section detection device to the ground when the magnetic cylinder (7) is not extended, and L2 is stored in the PLC controller as known data; C. Calculate L3=L1-L2 and store it in the PLC controller; D. When the casting pipe (1) is delivered from the preceding station to the supporting wheel frame (13), the laser sensor (4) detects the casting pipe (1) and determines that there is a pipe; the magnetic cylinder (7) extends and the cylinder sensor (10) is triggered, and it is determined that the pipe is abnormal; if the cylinder sensor (10) is not triggered, it is determined that the pipe is normal; E. Read the value of the laser sensor (4) to obtain the height L from the laser sensor (4) to the upper section of the casting tube (1). u1 , stored in the PLC controller; F. Read the value of the encoder (9) to obtain the extension length L of the magnetic cylinder (7) d1 , stored in the PLC controller, the diameter of the cast pipe (1) is now L x1 =L3-L u1 -L d1 ; G. Repeat the above steps EF to read the array data, add and average the results of each group of data to get the average value, which is used as the final calculation result and sent to the production line. The test is completed; L x = (L x1 + L x2 +……+ L xn ) / n, where L xn Indicates the result obtained by the nth test; And, it also includes a diameter detection device used by the above method, the diameter detection device includes: A supporting wheel frame (13), a stop block (5), a casting pipe upper section detection device, a casting pipe lower section detection device, a PLC controller and a casting pipe (1), wherein the casting pipe lower section detection device is located between the supporting wheel frame (13) and the stop block (5); the casting pipe upper section detection device comprises a bracket (2) and a laser sensor (4), wherein the laser sensor (4) is fixed to the end of the bracket (2); the casting pipe lower section detection device comprises a magnetic cylinder (7), a contact roller (8), an encoder (9), an upper connecting rod (11) and a lower connecting rod (12), wherein the magnetic cylinder (7) is vertically fixed to the ground by means of a base (6), and the contact roller (8) is fixed to the ground by means of a base (6). The auxiliary roller seat is fixed to the end of the piston rod of the magnetic cylinder (7); one end of the upper connecting rod (11) is hinged to the roller seat and the other end is connected to the encoder (9); one end of the lower connecting rod (12) is hinged to the base (6) and the other end is connected to the encoder (9); a magnetic cylinder sensor (10) is also provided on the outside of the magnetic cylinder (7); the center of the laser sensor (4), the center of the casting pipe (1) and the center of the contact roller (8) are vertically corresponding; the laser sensor (4), the limit block (5), the magnetic cylinder (7), the contact roller (8), the encoder (9) and the magnetic cylinder sensor (10) are all electrically connected to the PLC controller.

2. A diameter detection device suitable for a cast pipe production line, characterized in that: The invention comprises a supporting wheel frame (13), a stop block (5), a casting pipe upper cut surface detection device, a casting pipe lower cut surface detection device, a PLC controller and a casting pipe (1), wherein the casting pipe lower cut surface detection device is located between the supporting wheel frame (13) and the stop block (5); the casting pipe upper cut surface detection device comprises a bracket (2) and a laser sensor (4), wherein the laser sensor (4) is fixed to the end of the bracket (2); the casting pipe lower cut surface detection device comprises a magnetic cylinder (7), a contact roller (8), an encoder (9), an upper connecting rod (11) and a lower connecting rod (12), wherein the magnetic cylinder (7) is vertically fixed on the ground by means of a base (6), and the contact roller (8) is fixed to the ground by means of an encoder (9), an upper connecting rod (11) and a lower connecting rod (12). The piston rod end of the magnetic cylinder (7) is fixed to the roller seat by means of a roller seat, one end of the upper connecting rod (11) is hinged to the roller seat and the other end is connected to the encoder (9), one end of the lower connecting rod (12) is hinged to the base (6) and the other end is connected to the encoder (9); a magnetic cylinder sensor (10) is also provided on the outside of the magnetic cylinder (7); the center of the laser sensor (4), the center of the casting pipe (1) and the center of the contact roller (8) are vertically corresponding, and the laser sensor (4), the limit block (5), the magnetic cylinder (7), the contact roller (8), the encoder (9) and the magnetic cylinder sensor (10) are all electrically connected to a PLC controller.

3. A diameter detection device suitable for a cast pipe production line according to claim 2, characterized in that: A protective cover (3) is provided on the laser sensor (4), and the protective cover (3) is fixed on the bracket (2).

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