Automatic grinding equipment and grinding method for pipe end welding seam

Abstract

The invention relates to the technical field of steel pipe manufacturing, in particular to automatic pipe end welding seam grinding equipment and a grinding method, which are used for solving the problem that an existing device cannot efficiently and adaptively complete grinding of inner and outer welding seams at the pipe ends of steel pipes with different specifications, and the device comprises a conveying positioning mechanism, a welding seam recognition mechanism, a grinding execution mechanism and a control mechanism, the conveying and positioning mechanism is used for conveying steel pipes and transferring stations, the welding seam recognition mechanism is arranged on a measuring station and used for recognizing the initial position of a pipe end welding seam, the grinding executing mechanism is used for grinding inner and outer welding seams of the pipe end, and the control mechanism is used for controlling operation of the conveying and positioning mechanism, the welding seam recognition mechanism and the grinding executing mechanism. The method comprises the steps of steel pipe feeding, weld joint measuring, weld joint grinding and steel pipe discharging. Through cooperation of the welding seam recognition mechanism and the grinding execution mechanism, the welding seam of the steel pipe is automatically recognized and ground, and the production efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of steel pipe manufacturing technology, specifically to automatic grinding equipment and grinding method for pipe end welds. Background Technology

[0002] In the production process of straight seam submerged arc welded pipes, grinding the weld reinforcement at the pipe ends is a crucial step to ensure pipe quality and facilitate subsequent assembly welding. Currently, most steel pipe manufacturers in China still use manual handheld angle grinders for grinding, which results in high labor intensity, low efficiency, unstable quality, and a high risk of safety accidents.

[0003] A search revealed that some automated grinding devices already exist in the prior art, such as the "A Pipe End Weld Grinding Machine" with application number CN202321990489.2, which uses a fixed grinding head in conjunction with the rotation of the steel pipe for grinding. However, it is only suitable for grinding long straight welds and cannot adapt to local grinding of specific areas at the pipe end, nor does it have the ability to automatically adapt to different pipe diameters and grinding programs. Another published document, "Application of Automatic Grinding Technology for Pipe End Welds," published in the 4th issue of "Welded Pipe" in 2021, describes a device that, while achieving automated operation, still suffers from insufficient grinding accuracy (excess height control > 0.5mm), cumbersome adjustments when changing specifications, and the inability to process internal and external welds simultaneously. Summary of the Invention

[0004] This invention provides an automatic grinding equipment and method for pipe end welds to solve the problem that existing devices cannot efficiently and adaptively complete the grinding of internal and external welds on the pipe ends of steel pipes of different specifications.

[0005] To alleviate the above-mentioned technical problems, the technical solution provided by the present invention is as follows:

[0006] An automatic grinding equipment for pipe end welds includes a conveying and positioning mechanism, a weld identification mechanism, a grinding execution mechanism, and a control mechanism. The conveying and positioning mechanism is used for conveying steel pipes and transferring workstations. The weld identification mechanism is set at the measurement station and is used to identify the starting position of the pipe end weld. The grinding execution mechanism is used for grinding the inner and outer welds of the pipe end. The control mechanism is used to control the operation of the conveying and positioning mechanism, the weld identification mechanism, and the grinding execution mechanism.

[0007] Furthermore, the conveying and positioning mechanism includes a first transverse carriage and a second transverse carriage. Both the first transverse carriage and the second transverse carriage are equipped with multiple rotating rollers. The multiple rotating rollers are arranged in a V-shape in the cross-sectional direction. Both the first transverse carriage and the second transverse carriage are equipped with a driving device for driving the rotating rollers. The first transverse carriage is used to convey the steel pipe to the measuring station, and the second transverse carriage is used to convey the steel pipe to the grinding station.

[0008] Furthermore, the grinding actuator includes two six-axis industrial robots, which are symmetrically arranged at both ends of the steel pipe at the grinding station. One of the six-axis industrial robots is the main machine, and the other is the auxiliary machine. Each of the two six-axis industrial robots has a spindle mounted on its actuator arm, and each of the two spindles is equipped with a grinding tool, which includes a belt abrasive wheel and a disc milling cutter. The actuator arms of both six-axis industrial robots can move between the measuring station and the grinding station.

[0009] Furthermore, the weld seam recognition mechanism includes two vision sensors, which are respectively mounted on the actuator arms of the two six-axis industrial robots.

[0010] Furthermore, the control mechanism includes an operating console, which consists of a PLC master station, an HMI human-machine interface, a robot controller, and a remote I / O module. The PLC master station communicates with the conveying and positioning mechanism, the weld seam recognition mechanism, and the grinding execution mechanism via a Profinet bus.

[0011] An automated grinding method for pipe end welds, using automated pipe end weld grinding equipment, includes the following steps:

[0012] The control mechanism acquires pipe diameter parameters, grinding mode, and grinding length. The grinding mode includes external grinding mode and internal grinding mode. In the external grinding mode, the spindle of the six-axis industrial robot is equipped with a sanding belt wheel, which moves along the weld seam on the outer wall of the steel pipe. In the internal grinding mode, the spindle of the six-axis industrial robot is equipped with a disc milling cutter, which moves along the weld seam on the inner wall of the steel pipe.

[0013] The first transverse moving car is controlled to move the steel pipe to the measuring station, and after the steel pipe moves to the measuring station, the rotating roller is controlled to rotate the steel pipe.

[0014] Acquire weld data at both ends of the steel pipe as identified by the two vision sensors, wherein the weld data includes the coordinates of the weld start point, trajectory, and end point;

[0015] After the second traverse car receives the steel pipe from the first traverse car, the second traverse car is controlled to move the steel pipe to the grinding station.

[0016] Based on the pipe diameter parameters, the grinding mode, the grinding length, and the weld data, the six-axis industrial robot is controlled to drive the grinding tool from the weld start point, along the weld trajectory until it reaches the weld end point to perform the grinding operation;

[0017] Control the six-axis industrial robot to move to its original coordinate position and wait for command.

[0018] Furthermore, it also includes the second traverse vehicle delivering the steel pipe out of the grinding station while the two six-axis industrial robots move to their original coordinate positions to wait.

[0019] Furthermore, it also includes the following: during the process of the six-axis industrial robot driving the grinding tool to move along the weld track from the starting point of the weld to the end point of the weld, if the equipment stops running, the control mechanism records the current coordinate point of the six-axis industrial robot.

[0020] Furthermore, the grinding operation includes external weld seam grinding and internal weld seam grinding. When performing the external weld seam grinding, the control mechanism controls the execution arm of the main machine to move the vision sensor to the position of the external weld seam at one end of the steel pipe at the measurement station to locate the first external weld seam. After the first external weld seam is located, the control mechanism controls the execution arm of the auxiliary machine to move the vision sensor to the position of the external weld seam at the other end of the measurement station to locate the second external weld seam.

[0021] The system acquires weld data of the first outer weld and the second outer weld measured by two vision sensors on the main unit and the auxiliary unit's execution arm, and generates two grinding trajectories for the main unit and the auxiliary unit based on the two weld data.

[0022] According to the two grinding trajectories, the main machine and the auxiliary machine are respectively controlled to execute the external grinding mode;

[0023] After the external grinding mode ends, the two vision sensors are controlled to measure the first excess height of the first external weld and the second external weld, respectively.

[0024] Determine whether the first excess height is qualified. If it is, perform inner weld grinding. If not, repeat the outer weld grinding until the first excess height is qualified.

[0025] Furthermore, during the grinding of the inner weld seam, the control mechanism controls the execution arm of the main machine to move the vision sensor to the inner weld seam position at one end of the steel pipe at the measurement station to locate the first inner weld seam. After the first inner weld seam is located, the control mechanism controls the execution arm of the auxiliary machine to move the vision sensor to the inner weld seam position at the other end of the measurement station to locate the second inner weld seam.

[0026] The system acquires weld data of the first inner weld and the second inner weld measured by two vision sensors on the main unit and the auxiliary unit's execution arm, and generates two grinding trajectories for the main unit and the auxiliary unit based on the two weld data.

[0027] Based on the two grinding trajectories, the main machine and the auxiliary machine are respectively controlled to execute the internal grinding mode;

[0028] After the internal grinding mode ends, the two vision sensors are controlled to measure the second excess height of the first internal weld and the second internal weld, respectively.

[0029] Determine whether the second excess height is qualified. If it is, both the main machine and the auxiliary machine move to their original coordinate positions, and the second transverse car sends the steel pipe out of the grinding station. If not, repeat the grinding of the inner weld seam until the second excess height is qualified, and then send the steel pipe out of the grinding station.

[0030] The beneficial effects of this invention are analyzed as follows:

[0031] The automatic grinding equipment for pipe end welds includes a conveying and positioning mechanism, a weld recognition mechanism, a grinding execution mechanism, and a control mechanism. The conveying and positioning mechanism is used for conveying steel pipes and transferring workstations. The weld recognition mechanism is set at the measurement station to identify the starting position of the pipe end weld. The grinding execution mechanism is used for grinding the inner and outer welds of the pipe end. The control mechanism is used to control the operation of the conveying and positioning mechanism, the weld recognition mechanism, and the grinding execution mechanism.

[0032] The conveying and positioning mechanism receives the steel pipe and transports it to the measurement station. Subsequently, the weld seam identification mechanism uses visual recognition or laser scanning to detect the internal and external weld seams of the steel pipe. The control mechanism controls the grinding execution mechanism to operate based on the weld seam data scanned by the visual scanning mechanism, grinding the internal and external weld seams at both ends of the steel pipe. After grinding is completed, the conveying and positioning mechanism transports the steel pipe out. This device can grind steel pipes of different diameters. Through the cooperation of the weld seam identification mechanism and the grinding execution mechanism, the weld seams of the steel pipe are automatically identified and ground, improving production efficiency. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the grinding equipment of the present invention;

[0034] Figure 2 This is a flowchart of the steel pipe grinding process of the present invention;

[0035] Figure 3 This is a diagram of the HMI (Human-Machine Interface) of the present invention.

[0036] In the diagram: 1. First traverse vehicle; 2. Second traverse vehicle; 3. Six-axis industrial robot; 4. Spindle; 5. Control panel; 6. Vision sensor; 7. Steel pipe. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] Example 1, as Figure 1 As shown, the automatic grinding equipment for pipe end welds includes a conveying and positioning mechanism, a weld recognition mechanism, a grinding execution mechanism, and a control mechanism. The conveying and positioning mechanism is used for conveying the steel pipe 7 and transferring the workstation. The weld recognition mechanism is set at the measurement station to identify the starting position of the pipe end weld. The grinding execution mechanism is used for grinding the inner and outer welds of the pipe end. The control mechanism is used to control the operation of the conveying and positioning mechanism, the weld recognition mechanism, and the grinding execution mechanism.

[0039] The working mechanism of the automatic pipe end weld grinding equipment provided in this embodiment is as follows:

[0040] The conveying and positioning mechanism receives the steel pipe 7 and transports it to the measurement station. Subsequently, the weld seam recognition mechanism uses visual recognition or laser scanning to detect the internal and external weld seams of the steel pipe 7. The control mechanism controls the grinding execution mechanism to operate based on the weld seam data scanned by the visual scanning mechanism, grinding the internal and external weld seams at both ends of the steel pipe 7. After grinding is completed, the conveying and positioning mechanism transports the steel pipe 7 out. This device can grind steel pipes 7 of different diameters. Through the cooperation of the weld seam recognition mechanism and the grinding execution mechanism, the weld seams of the steel pipe 7 are automatically identified and ground, improving production efficiency.

[0041] Among the optional methods in this embodiment, the more preferred one is:

[0042] The conveying and positioning mechanism includes a first transverse carriage 1 and a second transverse carriage 2. Both the first transverse carriage 1 and the second transverse carriage 2 are equipped with multiple rotating rollers arranged in a V-shape in the cross-sectional direction. Both the first transverse carriage 1 and the second transverse carriage 2 are equipped with a drive device for driving the rotating rollers. The first transverse carriage 1 is used to convey the steel pipe 7 to the measuring station, and the second transverse carriage 2 is used to convey the steel pipe 7 to the grinding station.

[0043] The steel pipe 7 is first placed on the first transverse carriage 1. The first transverse carriage 1 moves the steel pipe 7 to the measurement station. Then the drive device drives the rotating roller to rotate, thereby causing the steel pipe 7 to rotate. At this time, the weld recognition mechanism recognizes the weld of the steel pipe 7 in the rotating state and obtains the starting position and trajectory of the weld.

[0044] Among the optional methods in this embodiment, the more preferred one is:

[0045] The grinding actuator includes two six-axis industrial robots 3, which are symmetrically arranged at both ends of the steel pipe 7 at the grinding station. One six-axis industrial robot 3 is the main machine, and the other six-axis industrial robot 3 is the auxiliary machine. Each of the two six-axis industrial robots 3 has a spindle 4 mounted on its actuator arm. Each of the two spindles 4 is equipped with grinding tools, including a belt abrasive wheel and a disc milling cutter. The actuator arms of the two six-axis industrial robots 3 can move between the measuring station and the grinding station.

[0046] Two six-axis industrial robots 3 serve as the main machine and the auxiliary machine, respectively. The main machine and the auxiliary machine are used to grind the welds at the two ends of the steel pipe 7. The welds of the steel pipe 7 are divided into an outer weld on the outer wall and an inner weld on the inner wall. When grinding the outer weld, a sanding wheel is installed on the main spindle 4. The actuator arm drives the sanding wheel to move along the weld trajectory on the outer wall of the steel pipe 7 to perform grinding. When grinding the inner weld, a disc milling cutter is installed on the main spindle 4. The actuator arm drives the disc milling cutter to move along the weld trajectory on the inner wall of the steel pipe 7 to perform grinding.

[0047] The actuator arm can also move to the measurement station and the grinding station. When the actuator arm moves to the measurement station, the weld identification mechanism operates, and when the actuator arm moves to the grinding station, the grinding actuator operates.

[0048] Among the optional methods in this embodiment, the more preferred one is:

[0049] The weld seam recognition mechanism includes two vision sensors 6, which are respectively mounted on the actuator arms of two six-axis industrial robots 3.

[0050] Two vision sensors 6 are mounted on the actuator arms of two six-axis industrial robots 3. The movement of the actuator arms drives the vision sensors 6 to the measurement station to identify the weld seam.

[0051] Among the optional methods in this embodiment, the more preferred one is:

[0052] The control mechanism includes an operator console 5, which consists of a PLC master station, an HMI human-machine interface, a robot controller, and a remote I / O module. The PLC master station communicates with the conveying and positioning mechanism, the weld seam recognition mechanism, and the grinding execution mechanism via the Profinet bus.

[0053] The HMI (Human Machine Interface) has interactive buttons for various operation modes such as "Automatic", "Manual", and "Single-sided Grinding", as well as a process parameter setting interface. The control mechanism has built-in grinding programs for different steel pipes (such as JLDM_XXW and JLDM_XXN), which can automatically call the corresponding program according to the input pipe diameter.

[0054] like Figure 2 As shown, the automatic grinding method for pipe end welds, using automatic pipe end weld grinding equipment, includes the following steps:

[0055] S1. The control mechanism acquires the pipe diameter parameters, grinding mode, and grinding length. The grinding mode includes external grinding mode and internal grinding mode. In external grinding mode, the spindle 4 of the six-axis industrial robot 3 is equipped with a sanding belt wheel and drives the sanding belt wheel to move on the weld seam of the outer wall of the steel pipe 7. In internal grinding mode, the spindle 4 of the six-axis industrial robot 3 is equipped with a disc milling cutter and drives the disc milling cutter to move on the weld seam of the inner wall of the steel pipe 7.

[0056] S2. Control the first transverse moving car 1 to move the steel pipe 7 to the measuring station, and after the steel pipe 7 moves to the measuring station, control the rotating roller to drive the steel pipe 7 to rotate.

[0057] S3. Acquire the weld data at both ends of the steel pipe 7 identified by the two vision sensors 6. The weld data includes the coordinates of the weld start point, trajectory, and end point.

[0058] S4. After the second transverse carriage 2 receives the steel pipe 7 from the first transverse carriage 1, control the second transverse carriage 2 to move the steel pipe 7 to the grinding station.

[0059] S5. Based on the pipe diameter parameters, grinding mode, grinding length and weld data, control the six-axis industrial robot 3 to drive the grinding tool from the weld start point and move along the weld trajectory until the weld end point to perform the grinding operation.

[0060] S6. Control the six-axis industrial robot 3 to move to the original coordinate position and wait.

[0061] Select either external or internal grinding mode according to grinding requirements, and install a grinding belt wheel or disc milling cutter on the spindle 4 according to the selected mode. After selecting the grinding mode, hoist the steel pipe 7 onto the first transverse carriage 1. The first transverse carriage 1 moves the steel pipe 7 to the measuring station. The rotating roller drives the steel pipe 7 to rotate. The vision sensor 6 scans the weld data and transmits the data to the control mechanism. At the same time, the pipe diameter data is also input to the control mechanism. The control mechanism combines the weld data and the pipe diameter data to control the six-axis industrial robot 3 to run and perform weld grinding.

[0062] Among the optional methods in this embodiment, the more preferred one is:

[0063] It also includes the second transverse transfer vehicle 2 sending the steel pipe 7 out of the grinding station while the two six-axis industrial robots 3 move to their original coordinate positions to wait.

[0064] After grinding is completed, the six-axis industrial robot 3 resets, and the second transverse carriage 2 sends out the steel pipe 7, after which the weld grinding of the next steel pipe 7 can be carried out.

[0065] Among the optional methods in this embodiment, the more preferred one is:

[0066] It also includes the following: if the equipment stops running during the process of the six-axis industrial robot 3 driving the grinding tool from the starting point of the weld seam and moving along the weld seam trajectory until it reaches the end point of the weld seam, the control mechanism records the current coordinate point of the six-axis industrial robot 3.

[0067] When the equipment malfunctions or the emergency stop button is triggered, the control mechanism records the coordinates of the six-axis industrial robot 3 in the current state, so that grinding can continue when the equipment is restored.

[0068] Among the optional methods in this embodiment, the more preferred one is:

[0069] The grinding operation includes external weld grinding and internal weld grinding. When performing external weld grinding, the control mechanism controls the execution arm of the host machine to move the vision sensor 6 to the external weld position of one end of the steel pipe 7 at the measurement station to locate the first external weld. After the first external weld is located, the control auxiliary machine's execution arm drives the vision sensor 6 to the external weld position of the other end of the measurement station to locate the second external weld.

[0070] The machine acquires weld data of the first and second outer welds measured by two vision sensors 6 on the main and auxiliary machine execution arms, and generates two grinding trajectories for the main and auxiliary machines based on the two weld data.

[0071] Based on the two grinding trajectories, the main machine and auxiliary machine are controlled to execute the external grinding mode respectively;

[0072] After the external grinding mode ends, control two vision sensors 6 to measure the first excess height of the first and second external welds respectively;

[0073] Determine whether the first excess height is qualified. If it is, perform inner weld grinding; if not, repeat outer weld grinding until the first excess height is qualified.

[0074] First, the external weld seam grinding is performed. After the main machine is positioned at the weld seam position at one end of the steel pipe 7, the auxiliary machine starts to run and positions the weld seam position at the other end of the steel pipe 7. Then, the main machine and the auxiliary machine run synchronously to grind the external weld seam. After the grinding is completed, the weld seam allowance at both ends of the steel pipe 7 is checked to see if it is qualified. If both are qualified, the main machine and the auxiliary machine perform the internal weld seam grinding. If one of them is unqualified, such as the main machine grinding being unqualified while the auxiliary machine grinding is qualified, the main machine continues to perform the external weld seam grinding, while the auxiliary machine performs the internal weld seam grinding. After the main machine performs the external weld seam grinding and the allowance is qualified, the main machine then performs the internal weld seam grinding.

[0075] Among the optional methods in this embodiment, the more preferred one is:

[0076] When performing internal weld grinding, the control mechanism controls the execution arm of the host machine to move the vision sensor 6 to the internal weld position of one end of the steel pipe 7 at the measurement station to locate the first internal weld. After the first internal weld is located, the control auxiliary machine's execution arm drives the vision sensor 6 to the internal weld position of the other end of the measurement station to locate the second internal weld.

[0077] The system acquires weld data of the first and second inner welds measured by two vision sensors 6 on the main and auxiliary machine execution arms, and generates two grinding trajectories for the main and auxiliary machines based on the two weld data.

[0078] Based on the two grinding trajectories, the main machine and auxiliary machine are controlled to execute the internal grinding mode respectively;

[0079] After the internal grinding mode ends, control two vision sensors 6 to measure the second excess height of the first and second internal welds respectively;

[0080] Determine whether the second excess height is qualified. If it is, both the main machine and the auxiliary machine move to the original coordinate position, and the second transverse moving car 2 sends the steel pipe 7 out of the grinding station. If not, repeat the grinding of the inner weld seam until the second excess height is qualified, and then send the steel pipe 7 out of the grinding station.

[0081] The grinding of the inner weld is performed only after the grinding of the outer weld is completed. After both the inner and outer welds are ground, the main machine and the auxiliary machine return to their original positions. After confirming that the current grinding process of steel pipe 7 is completed, the second transverse transfer car 2 transports steel pipe 7 out of the grinding station.

[0082] If steel pipe 7 needs to be repaired, the operation control mechanism will switch the working mode to manual. The second transverse car 2 will be manually operated to transport steel pipe 7 to the grinding station. The starting offset of internal or external grinding will be set on the millimeter interface. Then, the motor will manually grind one side. Subsequently, the corresponding six-axis industrial robot 3 will run according to the adjusted trajectory until the grinding of the weld seam meets the requirements.

[0083] Example 2, Grinding of the outer weld seam of Φ1016mm steel pipe 7:

[0084] The operator selects the pipe diameter "1016", grinding mode "external grinding", and grinding length "170mm" on the HMI interface;

[0085] The first transverse transfer vehicle 1 sends the steel pipe 7 into the measurement station. The steel pipe 7 rotates, and the vision sensor 6 identifies the starting point of the weld.

[0086] The second transverse transfer car 2 takes over and delivers the equipment to the grinding station. The six-axis industrial robot 3, which acts as the main unit, runs according to the program "JLDM_1016W" to complete the grinding of the outer weld seam.

[0087] After grinding, the weld reinforcement was found to be 0.2mm, which meets the process requirements.

[0088] Example 3, Grinding (repair) of the inner weld seam of Φ813mm steel pipe 7:

[0089] Switch the "Work Mode" to "Manual";

[0090] Manually operate the second transverse transfer carriage 2 to position the steel pipe 7 to the grinding station;

[0091] In the HMI interface, set "Internal grinding start offset + 5mm" and click "Manual single-sided grinding";

[0092] The six-axis industrial robot 3, acting as an auxiliary machine, runs along the adjusted trajectory to complete the grinding of the inner weld seam.

[0093] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automatic grinding equipment for pipe end welds, characterized in that: It includes a conveying and positioning mechanism, a weld seam identification mechanism, a grinding execution mechanism, and a control mechanism. The conveying and positioning mechanism is used for conveying the steel pipe (7) and transferring the work station. The weld seam identification mechanism is set at the measurement work station and is used to identify the starting position of the weld seam at the pipe end. The grinding execution mechanism is used for grinding the inner and outer weld seams at the pipe end. The control mechanism is used to control the operation of the conveying and positioning mechanism, the weld seam identification mechanism, and the grinding execution mechanism.

2. The automatic grinding equipment for pipe end welds according to claim 1, characterized in that: The conveying and positioning mechanism includes a first transverse carriage (1) and a second transverse carriage (2). Both the first transverse carriage (1) and the second transverse carriage (2) are equipped with multiple rotating rollers. The multiple rotating rollers are arranged in a V-shape in the cross-sectional direction. Both the first transverse carriage (1) and the second transverse carriage (2) are equipped with a driving device for driving the rotating rollers. The first transverse carriage (1) is used to convey the steel pipe (7) to the measuring station, and the second transverse carriage (2) is used to convey the steel pipe (7) to the grinding station.

3. The automatic grinding equipment for pipe end welds according to claim 2, characterized in that: The grinding actuator includes two six-axis industrial robots (3), which are symmetrically arranged at both ends of the steel pipe (7) of the grinding station. One of the six-axis industrial robots (3) is the main machine and the other six-axis industrial robot (3) is the auxiliary machine. A spindle (4) is installed on the execution arm of each of the two six-axis industrial robots (3). Grinding tools are installed on each of the two spindles (4). The grinding tools include a belt abrasive wheel and a disc milling cutter. The execution arms of the two six-axis industrial robots (3) can move between the measuring station and the grinding station.

4. The automatic grinding equipment for pipe end welds according to claim 3, characterized in that: The weld seam recognition mechanism includes two vision sensors (6), which are respectively mounted on the execution arms of the two six-axis industrial robots (3).

5. The automatic grinding equipment for pipe end welds according to claim 4, characterized in that: The control mechanism includes an operating console (5), which consists of a PLC master station, an HMI human-machine interface, a robot controller, and a remote I / O module. The PLC master station communicates with the conveying and positioning mechanism, the weld seam recognition mechanism, and the grinding execution mechanism via a Profinet bus.

6. An automatic grinding method for pipe end welds, using the automatic grinding equipment for pipe end welds as described in claim 5, characterized in that, Includes the following steps: The control mechanism acquires pipe diameter parameters, grinding mode and grinding length. The grinding mode includes external grinding mode and internal grinding mode. In the external grinding mode, the spindle (4) of the six-axis industrial robot (3) is equipped with a sanding belt wheel and drives the sanding belt wheel to move on the weld seam of the outer wall of the steel pipe (7). In the internal grinding mode, the spindle (4) of the six-axis industrial robot (3) is equipped with a disc milling cutter and drives the disc milling cutter to move on the weld seam of the inner wall of the steel pipe (7). Control the first transverse car (1) to move the steel pipe (7) to the measurement station, and after the steel pipe (7) moves to the measurement station, control the rotating roller to drive the steel pipe (7) to rotate; Acquire the weld data at both ends of the steel pipe (7) identified by the two vision sensors (6), the weld data including the coordinates of the weld start point, trajectory and end point; After the second transverse carriage (2) receives the steel pipe (7) from the first transverse carriage (1), the second transverse carriage (2) is controlled to move the steel pipe (7) to the grinding station; According to the pipe diameter parameters, the grinding mode, the grinding length and the weld data, the six-axis industrial robot (3) is controlled to drive the grinding tool from the weld start point and move along the weld trajectory until the weld end point to perform grinding operations; Control the six-axis industrial robot (3) to move to the original coordinate position to wait.

7. The automatic grinding method for pipe end welds according to claim 6, characterized in that: It also includes that, while the two six-axis industrial robots (3) move to their original coordinate positions to wait, the second traverse vehicle (2) sends the steel pipe (7) out of the grinding station.

8. The automatic grinding method for pipe end welds according to claim 6, characterized in that: It also includes that, during the process of the six-axis industrial robot (3) driving the grinding tool from the starting point of the weld seam and moving along the weld seam trajectory until reaching the end point of the weld seam, if the equipment stops running, the control mechanism records the current coordinate point of the six-axis industrial robot (3).

9. The automatic grinding method for pipe end welds according to claim 6, characterized in that: The grinding operation includes external weld grinding and internal weld grinding. When performing external weld grinding, the control mechanism controls the execution arm of the main machine to drive the vision sensor (6) to move to the position of the external weld at one end of the steel pipe (7) of the measurement station to locate the first external weld. After the first external weld is located, the control mechanism controls the execution arm of the auxiliary machine to drive the vision sensor (6) to move to the position of the external weld at the other end of the measurement station to locate the second external weld. The weld data of the first outer weld and the second outer weld measured by the two vision sensors (6) on the host and the auxiliary machine execution arm are obtained, and two grinding trajectories of the host and the auxiliary machine are generated based on the two weld data. According to the two grinding trajectories, the main machine and the auxiliary machine are respectively controlled to execute the external grinding mode; After the external grinding mode ends, the two vision sensors (6) are controlled to measure the first excess height of the first external weld and the second external weld respectively; Determine whether the first excess height is qualified. If it is, perform inner weld grinding. If not, repeat the outer weld grinding until the first excess height is qualified.

10. The automatic grinding method for pipe end welds according to claim 9, characterized in that: When performing the inner weld grinding, the control mechanism controls the execution arm of the main machine to drive the vision sensor (6) to move to the inner weld position of one end of the steel pipe (7) of the measurement station to locate the first inner weld. After the first inner weld is located, the control mechanism controls the execution arm of the auxiliary machine to drive the vision sensor (6) to move to the inner weld position of the other end of the measurement station to locate the second inner weld. The weld data of the first inner weld and the second inner weld measured by the two vision sensors (6) on the host and the auxiliary machine execution arm are obtained, and two grinding trajectories of the host and the auxiliary machine are generated based on the two weld data. Based on the two grinding trajectories, the main machine and the auxiliary machine are respectively controlled to execute the internal grinding mode; After the internal grinding mode ends, the two vision sensors (6) are controlled to measure the second excess height of the first internal weld and the second internal weld, respectively; Determine whether the second excess height is qualified. If it is, the main machine and the auxiliary machine are both moved to the original coordinate position, and the second transverse car (2) sends the steel pipe (7) out of the grinding station. If not, repeat the grinding of the inner weld until the second excess height is qualified and then send the steel pipe (7) out of the grinding station.

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