Tracking device for narrow gap submerged arc welding

Abstract

The present invention proposes a tracking device suitable for narrow gap submerged arc welding, which comprises a self-made contact measuring device (9), a non-contact measuring device (11), and a control system (12). The contact measuring device (9) is used for groove tracking, and the non-contact measuring device (11) and the control system (12) are used to monitor the distance between the two sides of the welding gun and the upper edge of the groove side wall. The contact measuring device (9) and the non-contact measuring device (11) are used simultaneously, and the contact measuring device (9) comprises a lateral measuring device and a height measuring device. The present invention fully utilizes the characteristics of the two measuring devices when they are used independently as tracking devices, gives full play to their respective advantages, makes up for the shortcomings of each when used independently as a tracking device, and further improves the stability and reliability of the tracking device.

Description

Technical field:

[0001] The invention relates to a tracking device suitable for narrow gap submerged arc welding. Background technology:

[0002] Narrow gap submerged arc welding technology is a process method for completing multi-layer and multi-pass welding in a groove that is much narrower than a conventional groove. It usually adopts a U-shaped or V-shaped groove, with a single-side angle of 0.5 to 1.5° (a total angle of 1 to 3°) and a minimum bottom width of 18 to 22 mm. The tracking device is the key and core of narrow gap submerged arc welding technology. The stability and reliability of this device are what users are most concerned about and expect. It is also the focus of continuous optimization, improvement, and upgrading of narrow gap equipment manufacturers. In recent years, non-contact sensors, such as laser measurement sensors, have gradually matured in the field of weld tracking. Due to its unique groove form, narrow gap submerged arc welding has high requirements for "relying solely" on non-contact sensors to achieve weld tracking, and it is required to have the following characteristics:

[0003] 1) A larger measuring range can ensure that the sensor can identify the bottom of the groove and that the installation position of the sensor is far enough away from the top of the groove to avoid being in a high temperature environment for a long time due to being too close to the top of the groove, which makes the sensor easy to be damaged.

[0004] 2) High resolution enables identification of lateral differences in very steep groove sidewalls (single-side angle 0.5°-1.5°) and accurate identification of the tangent point where the groove sidewall and weld transition smoothly. This also meets the process requirements of lateral accuracy ≤±0.25mm and height accuracy ≤±0.5mm.

[0005] For these reasons, non-contact sensors have not been widely used in narrow-gap submerged arc welding seam tracking. The few non-contact sensors that can be used in narrow-gap submerged arc welding conditions are very expensive.

[0006] The use of contact sensors is currently the only narrow-gap tracking method currently used in engineering applications in China. While this tracking device offers good stability and reliability, it is not without flaws. In long-term engineering practice, we have found that even when the tracking device is operating smoothly, welders still need to constantly monitor the distance between the welding torch and the groove sidewall to prevent tracking failure. This increases the welder's workload and can easily lead to fatigue.

[0007] Analysis of the causes of tracking failure revealed that the tracking device, which uses a contact sensor, is susceptible to interference from flux and dust, affecting transmission accuracy, thereby impacting tracking performance and even causing tracking failure, resulting in damage to the welding gun and tracking device. The tracking device operates at a high temperature (around 300°C) for a long period of time. After welding is stopped and the tracking device is lifted out of the groove, it is at room temperature. This alternating high and low temperature working environment can easily loosen the tracking device's mechanical connections, affecting its proper operation. Summary of the invention:

[0008] The purpose of the present invention is to provide a tracking device suitable for narrow gap submerged arc welding, overcome the defects and shortcomings of contact tracking devices and non-contact tracking devices, organically combine the two types of tracking devices, give full play to their respective advantages, and further improve the stability and reliability of the tracking device. The technical solution of the present invention is: a tracking device suitable for narrow gap submerged arc welding, consisting of a set of self-made contact measuring devices (9), a set of non-contact measuring devices (11), and a set of control systems (12), the contact measuring device (9) is used for groove tracking, the non-contact measuring device (11) and a set of control systems (12) are used to monitor the distance between the two sides of the welding gun and the upper edge of the groove side wall, the contact measuring device (9) and the non-contact measuring device (11) are used simultaneously, and the contact measuring device (9) is used by the lateral measuring device (11) to measure the distance between the two sides of the welding gun and the upper edge of the groove side wall. The invention is composed of a device and a height measuring device, wherein the height measuring device comprises: a displacement sensor (3) is installed on the upper end of a height tracking rod (5), and a height tracking wheel structure (7) is connected to the lower end of the height tracking rod (5); a lateral tracking device comprises: a potentiometer (4) is installed on the upper end of a lateral tracking rod (6), and a lateral left tracking claw (8) and a right tracking claw (15) are installed on the lower end of the lateral tracking rod (6); a non-contact measuring device (11) is connected to a control system (12) through a communication cable (13), and a contact measuring device (9) is connected to a welding gun (10). Located in the same set of cross slides (14); the lateral tracking device uses a left tracking claw (8) and a right tracking claw (15) that contact the two sides of the groove side wall, each tracking claw is connected to the second rod-shaped structure (6) and the other end is connected to the potentiometer (4), the angle between the left tracking claw (8) and the right tracking claw (15) and the groove side wall is transmitted to the potentiometer (4) through the second rod-shaped structure (6), and the potentiometer (4) sends different electrical signals to the control system, and the system uses this to judge the lateral distance between the welding gun and the bottom of the groove; the height measuring device uses a The wheel structure (7) in contact with the weld surface is connected to the first rod structure (5), and the other end of the first rod structure (5) is connected to a displacement sensor (3). The lifting and lowering of the wheel structure (7) is transmitted to the displacement sensor (3) through the first rod structure (5). The displacement sensor (3) sends different electrical signals and transmits them to the control system. The system uses this to determine the longitudinal distance between the bottom of the welding gun and the weld surface. The non-contact measuring device uses a laser distance sensor (11) and is placed on one side of the contact measuring device through a connecting mechanism (16).

[0009] The lateral tracking device comprises at least two groups and is arranged parallel to each other. The angle range of the groove (1) is 0.5-1.5 degrees, the width range of the groove (2) is 18-24 mm, the height tracking electrical component is a displacement sensor (3) with a model number of FXg-31, and the lateral tracking electrical component is a potentiometer (4) with a model number of WDD35D4.

[0010] The non-contact measuring device and the contact measuring device can be located on the same cross slide (14).

[0011] The non-contact measuring device and the contact measuring device can independently adopt a single set of cross slides (14).

[0012] The connecting mechanism (16) is connected to the cross slide. The connecting mechanism (16) is fixed by four M4*15 screws on a 70mm*70mm square 5mm thick carbon steel plate. A 180mm long and 2mm thick carbon steel hollow steel pipe is welded on the other side of the steel plate. The cross joint is used to connect the object with another 180mm long and 2mm thick carbon steel pipe welded with a columnar joint. The columnar joint is connected to the laser ranging sensor (11).

[0013] The technical solution principle of the present invention:

[0014] The present invention organically combines the two types of tracking devices, giving full play to their respective advantages and making up for the shortcomings of each when used independently as a tracking device.

[0015] When the workpiece groove is deep (≥30mm), a contact-type tracking device is used to track the weld seam. A non-contact measuring device is used to monitor the distance between the welding gun and the outer edge of the groove sidewall. When the contact measuring device is operating normally, the distance between the welding gun and the outer edge of the groove sidewall will be within a safe distance range. If the distance between the welding gun and the outer edge of the groove sidewall exceeds the safe distance, it must be a failure of the contact measuring device. At this time, the tracking device will issue an alarm and force the equipment to shut down to protect the safety of the welding equipment and welded products.

[0016] When the groove depth of the workpiece is shallow (≤30mm), or when the contact measuring device cannot be used to provide a tracking reference point, a non-contact measuring device can be used instead of the contact measuring device to provide lateral and height measurement data for weld tracking, or the non-contact measuring device is responsible for providing the lateral measurement data, and the height measurement data is still the responsibility of the contact measuring device.

[0017] The contact measuring device is located on the same cross slide as the welding gun. The non-contact measuring device can be located on the same slide as the contact measuring device or on a separate cross slide.

[0018] The beneficial effects of the present invention are:

[0019] The present invention makes full use of the characteristics of the two measuring devices when they are used independently as tracking devices. It brings out the greatest advantages of each and makes up for the shortcomings of each when used independently as a tracking device. It further improves the stability and reliability of the tracking device. When the groove depth is deep, the contact measuring device is used as the main method, and the non-contact measuring device is used as the auxiliary method. The non-contact measuring device is only used to measure the distance between the welding gun and the outer edge of the upper end of the groove. This measurement mode has low requirements for the sensor and is easy to implement at low cost. When the groove depth is shallow or the contact measuring device cannot be used to provide a tracking reference point, the non-contact measuring device can be used as the main method, and the machine contact type can be used as the auxiliary method, or the non-contact measuring device can be used completely. At this time, because the measurement position is close to the sensor, the requirements for the non-contact sensor are low, and it is easy to implement at low cost. Description of the drawings:

[0020] Figure 1 Schematic diagram of narrow gap submerged arc welding groove.

[0021] Figure 2 It is a schematic diagram of the composition of the device of the present invention.

[0022] Figure 3 Schematic diagram of the connection between the non-contact measuring device and the cross slide. Specific implementation method:

[0023] like Figure 2 As shown, a tracking device suitable for narrow gap submerged arc welding is composed of a self-made contact measuring device 9, a non-contact measuring device 11, and a control system 12. The contact measuring device 9 is used for groove tracking, and the non-contact measuring device 11 and a control system 12 are used to monitor the distance between the two sides of the welding gun and the upper edge of the groove side wall. The contact measuring device 9 and the non-contact measuring device 11 are used simultaneously. The contact measuring device 9 consists of a lateral measuring device and a height measuring device, wherein the height measuring device is: a displacement sensor 3 is installed at the upper end of the height tracking rod 5, and the lower end of the height tracking rod 5 is connected to the height tracking wheel structure 7; the lateral tracking device is: a potentiometer 4 is installed at the upper end of the lateral tracking rod 6, and a lateral left tracking claw 8 and a right tracking claw 15 are installed at the lower end of the lateral tracking rod 6. Figure 3As shown, the non-contact measuring device 11 is connected to the control system 12 via a communication cable 13, and the contact measuring device 9 and the welding gun 10 are located on the same cross slide 14. The lateral tracking device uses a left tracking claw 8 and a right tracking claw 15 that contact the side walls of the groove. Each tracking claw is connected to a second rod-shaped structure 6, and the other end is connected to a potentiometer 4. The angle between the left and right tracking claws 8 and 15 and the groove side walls is transmitted to the potentiometer 4 via the second rod-shaped structure 6. The potentiometer 4 generates different electrical signals that are transmitted to the control system, which uses these signals to determine the lateral distance between the welding gun and the bottom of the groove. The height measuring device uses a wheel-shaped structure 7 that contacts the weld surface and is connected to the first rod-shaped structure 5. The other end of the first rod-shaped structure 5 is connected to a displacement sensor 3. The lifting and lowering of the wheel-shaped structure 7 is transmitted through the first rod-shaped structure 5 to the displacement sensor 3. The displacement sensor 3 generates different electrical signals that are transmitted to the control system, which uses these signals to determine the longitudinal distance between the bottom of the welding gun and the weld surface. The non-contact measuring device uses a laser ranging sensor 11, which is mounted on one side of the contact measuring device via a connecting mechanism 16.

[0024] like Figure 1 As shown, there are at least two groups of lateral tracking devices arranged parallel to each other, the angle range of groove 1 is 0.5-1.5°, the width range of groove 2 is 18-24mm, the height tracking electrical component is a displacement sensor 3 with model FXg-31, and the lateral tracking electrical component is a potentiometer 4 with model WDD35D4.

[0025] The non-contact measuring device and the contact measuring device can be located on the same cross slide 14 .

[0026] The non-contact measuring device and the contact measuring device can independently use a single set of cross slides 14.

[0027] The connecting mechanism 16 is connected to the cross slide: the connecting mechanism 16 is fixed by four m4*15 screws on a 70mm*70mm square 5mm thick carbon steel plate. A 180mm long and 2mm thick carbon steel hollow pipe is welded on the other side of the steel plate. It is connected to another 180mm long and 2mm thick carbon steel pipe with a columnar joint welded together with a cross joint. The columnar joint is connected to the laser ranging sensor 11.

[0028] The contact measuring device consists of a lateral measuring device and a height measuring mechanism.

[0029] The lateral measurement device uses two tracking claws that contact the sidewalls of the groove. Each tracking claw is connected to a rod-like structure, the other end of which is connected to a potentiometer (or other electrical component). The principle of this lateral measurement device is that the angle of the tracking claw opening is linearly related to the lateral distance. This angle is transmitted to the potentiometer through the rod-like structure, and the resulting electrical signals are transmitted to the control system, which uses this to determine the lateral distance between the welding gun and the bottom of the groove.

[0030] When the system is not working, the tracking claw can be retracted to a position parallel to the welding gun. The process of retracting the tracking claw can be automatic or manual.

[0031] The height measurement mechanism has a similar principle to the lateral measurement device. It uses a wheel structure that contacts the weld surface and is connected to a rod structure. When the welding gun moves up, the rod structure descends, and when the welding gun moves down, the rod structure rises. The other end of the rod structure is connected to a potentiometer (or other electrical component). The rise and fall of the rod structure is converted into an electrical signal and transmitted to the control system. The system uses this to determine the longitudinal distance between the bottom of the welding gun and the weld surface.

[0032] The non-contact measurement device uses a laser distance sensor, mounted on one side of the contact measurement device via a connecting mechanism. This connection allows for adjustment of the laser distance sensor's height, lateral position, and angle relative to the workpiece surface. The laser sensor's position is adjusted so that its emitted light aligns with the workpiece and the contact measurement device. This allows the distance between the welding torch and both sides of the groove's outer edge, as well as the total width of the groove, to be measured. This measurement information is then transmitted to the control system.

[0033] The control system, comprised of a PLC and associated circuitry, receives electrical signal data from contact and non-contact measuring devices. Software within the control system analyzes and organizes this data to enable weld tracking and monitor contact measuring device failures.

[0034] The control system can achieve:

[0035] When the workpiece groove is deep (≥30mm), a contact-type tracking device is used to track the weld seam. A non-contact measuring device is used to monitor the distance between the welding gun and the outer edge of the groove sidewall. When the contact measuring device is operating normally, the distance between the welding gun and the outer edge of the groove sidewall will be within a safe distance range. If the distance between the welding gun and the outer edge of the groove sidewall exceeds the safe distance, it must be a failure of the contact measuring device. At this time, the tracking device will issue an alarm and force the equipment to shut down to protect the safety of the welding equipment and welded products.

[0036] When the groove depth of the workpiece is shallow (≤30mm), or when the contact measuring device cannot be used to provide a tracking reference point, a non-contact measuring device can be used instead of the contact measuring device to provide lateral and height measurement data for weld tracking, or the non-contact measuring device is responsible for providing the lateral measurement data, and the height measurement data is still the responsibility of the contact measuring device.

Claims

1. A tracking device suitable for narrow gap submerged arc welding, characterized by: The invention relates to a set of self-made contact measuring devices (9), a set of non-contact measuring devices (11), and a set of control systems (12). The contact measuring device (9) is used for groove tracking, and the non-contact measuring device (11) and a set of control systems (12) are used to monitor the distance between the two sides of the welding gun and the upper edge of the groove side wall. The contact measuring device (9) and the non-contact measuring device (11) are used simultaneously. The contact measuring device (9) is composed of a transverse measuring device and a height measuring device, wherein the height measuring device is: a displacement sensor (3) is installed at the upper end of a first rod-shaped structure (5), and the lower end of the first rod-shaped structure (5) is connected to a wheel structure (7); the transverse tracking device is: a potentiometer (4) is installed at the upper end of a second rod-shaped structure (6), and a transverse left tracking claw (8) and a right tracking claw (15) are installed at the lower end of the second rod-shaped structure (6). The non-contact measuring device (11) and the control system (12) are connected through a communication cable (13). The contact measuring device (9) and the welding gun (10) are located on the same set of cross slides (14). The invention relates to a horizontal tracking device, wherein the left tracking claw (8) and the right tracking claw (15) are in contact with both sides of the groove side wall, each tracking claw is connected to the second rod-shaped structure (6), and the other end is connected to the potentiometer (4). The angle between the left tracking claw (8) and the right tracking claw (15) and the groove side wall is transmitted to the potentiometer (4) through the second rod-shaped structure (6). The potentiometer (4) sends different electrical signals and transmits them to the control system. The system uses this to judge the horizontal distance between the welding gun and the bottom of the groove; the height measuring device adopts a wheel structure (7) in contact with the weld surface and is connected to the first rod-shaped structure (5). The other end of the first rod-shaped structure (5) is connected to a displacement sensor (3). The wheel structure (7) is raised and lowered and transmitted to the displacement sensor (3) through the first rod-shaped structure (5). The displacement sensor (3) sends different electrical signals and transmits them to the control system. The system uses this to judge the longitudinal distance between the bottom of the welding gun and the weld surface; the non-contact measuring device (11) adopts a laser distance sensor and is arranged on one side of the contact measuring device through a connecting mechanism (16).

2. A tracking device suitable for narrow gap submerged arc welding according to claim 1, characterized in that: The lateral tracking device comprises at least two groups and is arranged parallel to each other. The groove angle (1) ranges from 0.5 to 1.5 degrees, the groove width (2) ranges from 18 to 24 mm, the height tracking electrical component is a displacement sensor (3) with a model number of FXg-31, and the lateral tracking electrical component is a potentiometer (4) with a model number of WDD35D4.

3. The tracking device for narrow gap submerged arc welding according to claim 1, characterized in that: The non-contact measuring device (11) and the contact measuring device are located on the same set of cross slides (14).

4. The tracking device for narrow gap submerged arc welding according to claim 1, characterized in that: The non-contact measuring device (11) and the contact measuring device independently use a single set of cross slides (14).

5. The tracking device for narrow gap submerged arc welding according to claim 1, characterized in that: The connecting mechanism (16) is connected to the cross slide. The connecting mechanism (16) is fixed by four M4*15 screws on a 70mm*70mm square 5mm thick carbon steel plate. A 180mm long and 2mm thick carbon steel hollow steel pipe is welded on the other side of the steel plate. The cross joint is used to connect the object with another 180mm long and 2mm thick carbon steel pipe welded with a columnar joint. The columnar joint is connected to the laser ranging sensor.

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