Online laser heat treatment device and heat treatment method for pipeline welding joint

Abstract

The invention relates to an online laser heat treatment device and method for a pipeline welding joint. The device comprises an openable clamping assembly matched with a pipeline; a lifting mechanism, a laser heat treatment mechanism and a cooling treatment mechanism are correspondingly arranged on the two clamping assemblies; a clamping control assembly is arranged to be matched with the clamping assembly. A controller is arranged in cooperation with the lifting mechanism, the laser heat treatment mechanism, the cooling treatment mechanism and the clamping control assembly; after the pipeline is welded, the controller controls the clamping assembly to be opened, and after the clamping assembly is buckled to the preset position of the outer side of the pipeline, the clamping assembly is controlled to be closed; and the lifting mechanism is controlled to enable the whole device to move in the pipeline direction, and the laser heat treatment mechanism and the cooling treatment mechanism are controlled to sequentially machine the joint positions till laser heat treatment is completed in the whole welding joint area. The device has the characteristics of flexibility, adjustability, adaptability to the field environment, integrated control, high efficiency and energy conservation, and provides reliable technical support for long-period safe operation of a pipeline welding structure.

Description

Technical Field

[0001] This invention relates to the technical fields of brazing or desoldering; welding; cladding or plating by brazing or welding methods; localized heating cutting, such as flame cutting; and processing with laser beams, and particularly to an online laser heat treatment device and method for pipe welding joints. Background Technology

[0002] In the modern energy and power industry, pipelines serve as crucial carriers for transporting various fluids, such as oil, natural gas, and high-temperature steam. Their long-term safe and stable operation directly impacts the reliability and safe production of the entire energy system. Welded joints are often the weakest points in pipeline structures. This is primarily because during welding, the material undergoes rapid thermal cycling and uneven cooling, leading to significant structural changes and residual stresses in the weld and heat-affected zone. If these residual stresses are not effectively eliminated or controlled, they will become potential crack initiation sources during pipeline service, significantly increasing the risk of failure modes such as brittle fracture, stress corrosion cracking, and fatigue failure, severely affecting the pipeline's service life and operational safety.

[0003] Therefore, post-weld heat treatment of important welded structures such as pipelines has become an indispensable process in industry. The aim is to reduce residual stress, improve microstructure, and enhance joint toughness and corrosion resistance by controlling temperature and cooling process, thereby ensuring the safe service performance of the overall equipment.

[0004] Currently, induction heat treatment is one of the commonly used processes for online heat treatment of welded joints in industrial settings. This technology utilizes the principle of electromagnetic induction to generate eddy currents on the surface of the workpiece, thereby achieving heating. While it has certain applicability in the field, it still has several significant limitations: First, it has high energy consumption, especially with low thermal efficiency in the treatment of thick or large-diameter pipes; second, it is prone to thermal deformation of the workpiece during the heating process, which is particularly unfavorable in situations requiring high dimensional accuracy; third, the effectiveness of induction heat treatment is highly dependent on the distance between the induction coil and the workpiece surface. Changes in pipe position, roundness, and surface condition during on-site construction can easily lead to gap fluctuations, resulting in uneven heating, decreased temperature control accuracy, and seriously affecting process stability and repeatability.

[0005] In contrast, laser technology, with its concentrated energy, high controllability, low heat input, and non-contact processing, offers new possibilities for localized heat treatment of welded joints. Laser surface modification technology has been widely used in many fields, offering advantages such as good accessibility, high energy efficiency, narrow heat-affected zone, small deformation, and environmental friendliness. It can achieve precise and localized microstructure control and stress reconstruction. However, despite the outstanding performance of laser technology in surface modification, most existing laser surface annealing equipment is limited to fixed workstations or laboratory environments, lacking online, flexible, and integrated solutions suitable for complex structures such as circumferential welds in pipelines. This makes it difficult to directly apply to on-site heat treatment of pipeline welded joints in energy, chemical, and other fields.

[0006] Therefore, developing a laser heat treatment device for pipeline welded joints that can achieve on-site online stress control and microstructure optimization is of significant engineering necessity and technological innovation value. Summary of the Invention

[0007] This invention solves the problems existing in the prior art and provides an online laser heat treatment device and heat treatment method for pipe welded joints.

[0008] The technical solution adopted in this invention is an online laser heat treatment device for pipe welding joints. The device includes an openable clamping assembly that is configured to cooperate with the pipe. A lifting mechanism, a laser heat treatment mechanism, and a cooling treatment mechanism are correspondingly provided on the two clamping assemblies. A clamping control component is provided in conjunction with the clamping assembly; A controller is provided to work in conjunction with the lifting mechanism, laser heat treatment mechanism, cooling mechanism and clamping control assembly.

[0009] Preferably, the clamping control component includes a first motor mounted on a mounting base, a bidirectional screw horizontally mounted at the output end of the first motor, two nuts mounted on the bidirectional screw, a connecting rod corresponding to each nut, and each connecting rod cooperating with a corresponding clamping component.

[0010] Preferably, any of the clamping components includes a clamping base connected to a corresponding connecting rod; each of the two clamping bases is provided with a lower bushing, and the two lower bushings are sleeved on the lower part of the fixed shaft; a platform is provided on the clamping base, and a plurality of laser heat treatment mechanisms are provided on any of the platforms.

[0011] Preferably, all of the laser heat treatment mechanisms are evenly distributed on the circumference.

[0012] Preferably, any of the clamping bases is provided with a cooling mechanism, which includes one or more cooling heads.

[0013] Preferably, any of the clamping components further includes a clamping ring correspondingly disposed above the clamping base, and a synchronizing rod is provided between the two clamping rings and the clamping base; a lifting mechanism is provided in conjunction with the clamping rings.

[0014] Preferably, the lifting mechanism includes at least one drive wheel located inside the clamping ring, a wheel seat is provided on the clamping ring that cooperates with the drive wheel, and a second motor is provided outside the wheel seat that cooperates with the drive wheel.

[0015] Preferably, the inner sides of the two clamping rings are provided with a plurality of driven wheels.

[0016] Preferably, each of the two clamping rings is provided with an upper shaft sleeve, and the two upper shaft sleeves are sleeved on the upper part of the fixed shaft.

[0017] A heat treatment method of the online laser heat treatment device for pipe welded joints, wherein after the pipe is welded, the controller controls the clamping control component to open the clamping component and snap it into a preset position on the outside of the pipe, and then controls the clamping control component to close the clamping component; the lifting mechanism is controlled to move the whole device along the pipe direction, and the laser heat treatment mechanism and the cooling treatment mechanism are controlled to process the joint position in sequence until the entire welded joint area is laser heat treated.

[0018] This invention relates to an online laser heat treatment device and method for pipe welded joints. The device includes an openable clamping assembly that is configured to work with the pipe; two clamping assemblies are respectively provided with a lifting mechanism, a laser heat treatment mechanism, and a cooling mechanism; a clamping control assembly is provided in conjunction with the clamping assemblies; a controller is provided in conjunction with the lifting mechanism, the laser heat treatment mechanism, the cooling mechanism, and the clamping control assembly; after welding on the pipe, the controller controls the clamping assembly to open, and after it is fastened to a preset position on the outside of the pipe, the controller controls the clamping assembly to close; the lifting mechanism is controlled to move the entire device along the pipe direction, and the laser heat treatment mechanism and the cooling mechanism are controlled to process the joint position sequentially until the entire welded joint area has been laser heat treated.

[0019] The beneficial effects of this invention are that it combines the characteristics of flexibility and adjustability, adaptability to the site environment, integrated control and high efficiency and energy saving, providing reliable technical support for the long-term safe operation of pipeline welding structures. Attached Figure Description

[0020] Figure 1 This is a top-view perspective structural schematic diagram of the present invention; Figure 2 This is a three-dimensional structural diagram of the present invention viewed from a low angle. Detailed Implementation

[0021] The present invention will be further described in detail below with reference to embodiments, but the scope of protection of the present invention is not limited thereto.

[0022] This invention relates to an online laser heat treatment device for pipe welded joints. The device includes an openable clamping assembly that is configured to fit the pipe. Two clamping assemblies are respectively provided with a lifting mechanism, a laser heat treatment mechanism 1, and a cooling treatment mechanism. A clamping control component is provided in conjunction with the clamping assembly; A controller is provided to work in conjunction with the lifting mechanism, laser heat treatment mechanism 1, cooling treatment mechanism and clamping control assembly.

[0023] In this invention, the adjustable clamping of the pipe is achieved by an openable clamping assembly. After clamping the pipe, the lifting mechanism drives the entire device to move upward along the pipe wall. During the process, the laser heat treatment mechanism 1 first performs laser heat treatment on the preset position of the pipe, and then the cooling treatment mechanism cools the laser heat treatment position.

[0024] Obviously, the inner diameter of the openable clamping component matches the outer diameter of the pipe, and when the openable clamping component is in the clamping state, it abuts against the outer wall of the pipe; whether the clamping component is opened or closed is achieved by the output control signal of the clamping control component.

[0025] The controller in this invention controls the lifting mechanism, the laser heat treatment mechanism 1 outputs laser, the cooling treatment mechanism blows the cooling medium, and the clamping control component controls the output; those skilled in the art can set these according to their needs.

[0026] The clamping control component includes a first motor 3 mounted on the mounting base 2, and a bidirectional screw 4 horizontally mounted at the output end of the first motor 3. Two nuts 5 are fitted on the bidirectional screw 4, and a connecting rod 6 is provided corresponding to each nut 5. Each connecting rod 6 is configured to cooperate with the corresponding clamping component.

[0027] In this invention, a mounting base 2 is provided, and a first motor 3 is mounted on the mounting base 2. The output of the first motor 3 drives the rotation of the bidirectional screw 4, which in turn drives the two nuts 5 on it to move in opposite directions or in opposite directions. Obviously, the two nuts 5 are installed at opposite thread sections of the bidirectional screw 4. As the two nuts 5 move in opposite directions or in opposite directions, the connecting rod 6 connected to them is generally hinged at the bottom of the nuts 5, which can drive the corresponding clamping components to adjust their positions.

[0028] In this invention, considering the overall precision of the device, in order to ensure its fit with the pipeline, it is necessary to prevent its opening and closing range from being too large and to facilitate fine-tuning of its position; therefore, one end of the connecting rod 6 is hinged to the corresponding nut 5, and the other end of the connecting rod 6 is hinged to the lug 7 located on the side of the clamping assembly; that is, taking the relative movement of the nut 5 as an example, during the process, it does not directly pull the connecting rod 6 to move in the horizontal direction, but gives a movement "trend", so that the connecting rod 6 can drive the lug 7 to slowly open outward at a certain angle.

[0029] Each of the clamping components includes a clamping base 8 connected to the corresponding connecting rod 6; each of the two clamping bases 8 is provided with a lower bushing 9, and the two lower bushings 9 are sleeved on the lower part of the fixed shaft 10; a platform 11 is provided on the clamping base 8, and a plurality of laser heat treatment mechanisms 1 are provided on any of the platforms 11.

[0030] In this invention, the clamping base 8 is actually two semi-ring parts. Under the control of the clamping control component, the lower bushing 9 of the clamping base 8 can be opened or closed around the fixed shaft 10 to achieve clamping and limit its reference position. Obviously, the fixed shaft 10 is fixedly connected to the mounting base 2 and needs to be through when necessary, as shown in the figure.

[0031] Furthermore, a laser heat treatment mechanism 1 is set on the stage 11 provided on the clamping base 8. Generally, two are set on each clamping base 8. All the laser heat treatment mechanisms 1 are evenly distributed on the circumference to ensure uniform laser heat treatment of the pipeline. The laser heat treatment mechanism 1 includes a laser head and a fiber laser connected to its end, which generates rectangular light spots with different energy distributions to act on the processing position. This is something that is easy for those skilled in the art to understand, and those skilled in the art can set it up according to their needs.

[0032] Each of the clamping bases 8 is provided with a cooling mechanism, which includes one or more cooling heads 12.

[0033] In this invention, specifically, in order to achieve better uniform cooling, a connecting channel is provided for the cooling head 12 of each clamping base 8. The channel is arranged in a semi-circular manner along the inner sidewall of the clamping base 8 and has a rectangular outlet 13 for blowing compressed air onto the surface of the workpiece to control the cooling rate.

[0034] Each of the clamping components further includes a clamping ring 14 correspondingly disposed above the clamping base 8, and a synchronizing rod 15 is provided between the two clamping rings 14 and the clamping base 8; a lifting mechanism is provided in conjunction with the clamping rings 14.

[0035] The lifting mechanism includes at least one drive wheel 16 located inside the clamping ring 14. A wheel seat 17 is provided on the clamping ring 14 that cooperates with the drive wheel 16. A second motor 18 is provided outside the wheel seat 17 that cooperates with the drive wheel 16.

[0036] In this invention, the opening and closing of the clamping base 8 drives the opening and closing of the clamping ring 14 via the synchronizing rod 15. Then, the second motor 18 outputs driving force to drive the overall device to rise and fall, generally with climbing as the main method. In order to ensure sufficient contact between the clamping ring 14 and the pipe and to avoid the upward speed of the device drive wheel 16 side being too fast, several driven wheels 19 are provided on the inner side of the two clamping rings 14 to ensure that the two clamping components move synchronously.

[0037] To ensure the overall stability of the device, each of the two clamping rings 14 is provided with an upper shaft sleeve 20, and the two upper shaft sleeves 20 are sleeved on the upper part of the fixed shaft 10.

[0038] This invention relates to a heat treatment method of an online laser heat treatment device for pipe welded joints. After the pipe is welded, the controller opens the clamping component by controlling the clamping control component, and after it is fastened to a preset position on the outside of the pipe, the clamping component closes by controlling the clamping control component. The lifting mechanism is controlled to move the entire device along the pipe direction, and the laser heat treatment mechanism 1 and the cooling treatment mechanism are controlled to process the joint position in sequence until the entire welded joint area is laser heat treated.

[0039] In this invention, before performing the heat treatment method, a self-test is first required, including monitoring whether the lifting mechanism, laser heat treatment mechanism 1, cooling mechanism, clamping control component and controller are all operating normally.

[0040] Subsequently, based on the pipe material and reinforcement requirements, the process parameters of the device were set, adjusting the laser power, scanning speed, and compressed gas flow rate. Specifically, for the steel pipe material Ti6Al4V with an outer diameter of 100 mm, the laser power was adjusted to a range of 3000~6000 W, and the optical elements inside the laser head were adjusted according to the pipe size to adjust the spot size to 20×20~100×20 mm. 2 The scanning is performed on weld joints of the appropriate size, with a scanning speed ranging from 1 to 5 mm / s and a cooling compressed gas flow rate ranging from 10 to 60 L / min. The compressed gas is nitrogen.

[0041] After the pretreatment is completed, the heat treatment method is performed, including adjusting the opening and closing displacement of the bidirectional screw 4 and the driving clamping base 8 to fix the relative position of the device and the pipeline. Then, the second motor 18 drives the drive wheel 16 to move the whole device along the pipeline direction. The laser heat treatment mechanism 1 and the cooling treatment mechanism process the welded joint in sequence until the entire welded joint area is laser heat treated.

[0042] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An online laser heat treatment device for pipe welded joints, characterized in that: The device includes an openable clamping assembly that is configured to cooperate with the pipeline; the two clamping assemblies are respectively provided with a lifting mechanism, a laser heat treatment mechanism and a cooling treatment mechanism; A clamping control component is provided in conjunction with the clamping assembly; A controller is provided to work in conjunction with the lifting mechanism, laser heat treatment mechanism, cooling mechanism and clamping control assembly.

2. The online laser heat treatment device for pipe welding joints according to claim 1, characterized in that: The clamping control component includes a first motor mounted on a mounting base, a bidirectional screw horizontally mounted at the output end of the first motor, two nuts mounted on the bidirectional screw, a connecting rod corresponding to each nut, and each connecting rod cooperating with a corresponding clamping component.

3. The online laser heat treatment device for pipe welding joints according to claim 2, characterized in that: Each of the clamping components includes a clamping base connected to a corresponding connecting rod; each of the two clamping bases is provided with a lower bushing, and the two lower bushings are sleeved on the lower part of the fixed shaft; a platform is provided on the clamping base, and a plurality of laser heat treatment mechanisms are provided on any of the platforms.

4. The online laser heat treatment device for pipe welding joints according to claim 3, characterized in that: All of the laser heat treatment mechanisms are evenly distributed on the circumference.

5. The online laser heat treatment device for pipe welding joints according to claim 3, characterized in that: Each of the clamping bases is provided with a cooling mechanism, which includes one or more cooling heads.

6. The online laser heat treatment device for pipe welding joints according to claim 3, characterized in that: Each of the clamping components further includes a clamping ring correspondingly disposed above the clamping base, and a synchronizing rod is provided between the two clamping rings and the clamping base; a lifting mechanism is provided in conjunction with the clamping rings.

7. The online laser heat treatment device for pipe welding joints according to claim 6, characterized in that: The lifting mechanism includes at least one drive wheel located inside the clamping ring. A wheel seat is provided on the clamping ring that cooperates with the drive wheel, and a second motor is provided outside the wheel seat that cooperates with the drive wheel.

8. The online laser heat treatment device for pipe welding joints according to claim 7, characterized in that: The inner side of each of the two clamping rings is provided with several driven wheels.

9. The online laser heat treatment device for pipe welding joints according to claim 6, characterized in that: Each of the two clamping rings is provided with an upper shaft sleeve, and the two upper shaft sleeves are sleeved on the upper part of the fixed shaft.

10. A heat treatment method for an online laser heat treatment apparatus for pipe welded joints according to any one of claims 1 to 9, characterized in that: After the pipeline is welded, the controller opens the clamping component by controlling the clamping control component, and after it is fastened to the preset position on the outside of the pipeline, the controller closes the clamping component by controlling the clamping control component; the controller controls the lifting mechanism to move the whole device along the pipeline direction, and controls the laser heat treatment mechanism and the cooling treatment mechanism to process the joint position in sequence until the entire welded joint area is laser heat treated.

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