A large-diameter straight-seam welded pipe preheating device

Abstract

The utility model discloses a large -calibre straight seam welded pipe preheating device, including for the straight seam welded pipe weld area to the preheating of weld heating mechanism still includes locates the bearing assembly of weld heating mechanism top, is used for the magnetic attraction subassembly of the straight seam welded pipe removal, and is used for the heating element of the straight seam welded pipe weld just above area heating, heating element locates magnetic attraction subassembly, magnetic attraction subassembly movable locates bearing assembly. The utility model through magnetic attraction subassembly will hang in midair adsorption welded pipe and can along bearing assembly flexible removal, thoroughly solved the large -calibre pipe body movement, the problem of difficult placement, set up the basis of conventional heating mechanism below the weld, just above the weld additional compensation heating element with magnetic attraction subassembly synchronous movement, realize weld upper and lower both sides synchronous heating, effectively restrain uneven thermal expansion and contraction deformation to improve the preheating uniformity, reduce subsequent welding defect.

Description

Technical Field

[0001] This utility model belongs to the field of metal pipe welding technology, and in particular relates to a preheating device for straight seam welded pipes. Background Technology

[0002] In the manufacturing process of straight seam welded pipes, the weld preheating process is a key step to ensure welding quality. Especially for large-diameter welded pipes, sufficient preheating can effectively reduce the cooling rate of the weld area, reduce the hardening tendency of the heat-affected zone, and play a decisive role in preventing weld cracks, reducing residual stress, and improving the mechanical properties of the joint.

[0003] Currently, the preheating process for straight seam welded pipes primarily serves the subsequent internal welding process. It typically employs a weld-facing arrangement, with the weld area preheated on one side using methods such as flame heating. However, this one-sided heating mode causes the weld side to expand due to high temperature, while the pipe body area directly opposite the weld contracts at a relatively low temperature, easily leading to uneven thermal expansion and contraction deformation in large-diameter straight seam welded pipes. Furthermore, moving and placing large-diameter welded pipes on the preheating device presents numerous inconveniences. Therefore, there is an urgent need for a preheating device for large-diameter straight seam welded pipes that is both easy to move and capable of compensating for heating on the opposite side of the weld. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the deficiencies and defects mentioned in the background art above, and to provide a preheating device for large-diameter straight seam welded pipes that is convenient for transferring welded pipes on the preheating device and is not prone to deformation during the weld preheating process.

[0005] To solve the above-mentioned technical problems, the technical solution proposed by this utility model is as follows: A preheating device for large-diameter straight seam welded pipe includes a weld heating mechanism for preheating the downward-facing area of ​​the weld seam of the straight seam welded pipe, a support component disposed above the weld heating mechanism, a magnetic suction component for transferring the straight seam welded pipe, and a heating element for heating the area directly above the weld seam of the straight seam welded pipe. The heating element is disposed on the magnetic suction component, and the magnetic suction component is movably disposed on the support component.

[0006] In the aforementioned large-diameter straight seam welded pipe preheating device, preferably, the supporting component includes a set of gantry frames spaced apart along the length of the straight seam welded pipe. The gantry frames span above the weld heating mechanism. The magnetic suction component is arranged along the length of the straight seam welded pipe and is horizontally movable along the width of the straight seam welded pipe on the gantry frames. The magnetic suction component can move horizontally along the gantry frames in the width direction of the welded pipe, allowing it to flexibly attract the welded pipe to be preheated from beside the heating mechanism, then accurately move it directly above the weld heating mechanism and stably place the welded pipe in position. Simultaneously, it attracts and moves the preheated welded pipe out of the weld heating mechanism, simplifying the pipe loading, positioning, and unloading process.

[0007] In the above-mentioned large-diameter straight seam welded pipe preheating device, preferably, the magnetic suction assembly includes a sliding crossbeam and a magnetic suction element arranged along the length direction of the straight seam welded pipe. The sliding crossbeam is horizontally movable along the width direction of the straight seam welded pipe and is arranged on the gantry frame. The magnetic suction element is vertically movable below the sliding crossbeam via a lifting drive assembly. The heating element is attached to the upper end face of the magnetic suction element along the length direction of the straight seam welded pipe. The sliding crossbeam provides stable support for the magnetic suction component, allowing it to slide horizontally and precisely position itself for adsorption. The magnetic suction component extends along the length of the welded pipe, resulting in a large contact area with the pipe wall and generating a uniform and powerful magnetic force, ensuring no deviation or shaking during the transfer of large-diameter welded pipes. The heating element is attached to the upper surface of the magnetic suction component along the length of the welded pipe, requiring no additional positioning adjustments. It automatically and precisely covers the area directly above the weld seam when adsorbing the welded pipe, improving preheating efficiency. The lifting drive assembly allows the magnetic suction component to move up and down, coordinating with the lateral movement of the sliding crossbeam to achieve flexible positioning of the magnetic suction component in space. This facilitates adaptation to the preheating needs of welded pipes of different specifications and locations, enhancing the versatility and operational flexibility of the device.

[0008] In the aforementioned preheating device for large-diameter straight seam welded pipes, preferably, the upper end face of the magnetic suction component is provided with a groove along the length direction of the straight seam welded pipe, and the heating element consists of multiple heating cables arranged along the length direction of the straight seam welded pipe, with the heating cables attached to the groove. By creating a groove along the weld length, the arrangement trajectory of the heating cables is defined, forming a continuous and uniform linear heat source, effectively avoiding single-point overheating or blind spots, significantly improving the uniformity of weld preheating, and the groove also prevents the heating cables from slipping or being subjected to mechanical impact, improving the stability of the heating cables.

[0009] In the aforementioned preheating device for large-diameter straight seam welded pipes, preferably, the upper end face of the gantry frame is provided with a slide rail along the width direction of the straight seam welded pipe, and both ends of the sliding crossbeam are respectively provided with sliders for sliding back and forth on the slide rail. The slide rail is horizontally placed at the top of the gantry frame, and the two ends of the sliding crossbeam are engaged with sliders to form a low-friction, high-rigidity linear guiding system. The precise fit between the sliders and the slide rail allows the crossbeam to move smoothly and quickly back and forth along the width direction of the welded pipe with high positioning accuracy. At the same time, the slide rail-slider structure has strong load-bearing capacity, can withstand the heavy load of large-diameter pipes for a long time without deformation, and is easy to maintain, further improving the stability and service life of the device.

[0010] In the aforementioned preheating device for large-diameter straight seam welded pipes, preferably, the lifting drive assembly includes multiple vertically and evenly spaced lifting drive components. The lower end of each lifting drive component is fixed to a long strip-shaped mounting base arranged along the length of the straight seam welded pipe. The heating element and the magnetic suction component are located at the lower end of the long strip-shaped mounting base. By simultaneously driving the long strip-shaped mounting base with multiple vertically and evenly spaced lifting drive components, the magnetic suction component and the heating element experience consistent force and move up and down synchronously along the entire length of the weld, avoiding deflection deformation caused by single-point driving. The long strip-shaped mounting base integrates the dispersed driving force into an overall rigid support, significantly improving the overall bending stiffness. It can stably adsorb large-diameter pipes, easily adapt to ultra-long pipe fittings, has a simple structure, high rigidity, low maintenance, and significantly improves the reliability and safety of the preheating process.

[0011] In the aforementioned preheating device for large-diameter straight seam welded pipes, preferably, the weld heating mechanism includes a container with an open top and filled with heat-conducting sand, and a heat source assembly located below the container for heating the heat-conducting sand. The straight seam welded pipe is positioned with the weld seam facing downwards on the heat-conducting sand. The weld heating mechanism preheats the straight seam welded pipe using heat-conducting sand. Since the heat-conducting sand acts as an insulating medium, it stores heat for a long time and releases it slowly. The gaps between the heat-conducting sand particles create a uniform thermal environment. Heat gradually diffuses into the interior of the straight seam welded pipe through heat conduction and convection. Its insulating properties prolong the heating time, ensuring that the deeper materials are fully heated, achieving uniform heating temperature, guaranteeing the heating thickness during the preheating process of multi-diameter welded pipes, effectively avoiding local overheating or insufficient preheating, and providing a good foundation for subsequent welding processes.

[0012] In the aforementioned preheating device for large-diameter straight seam welded pipes, preferably, the heat source assembly includes multiple gas guiding channels arranged along the length of the straight seam welded pipe, several flame nozzles disposed on the gas guiding channels, and an igniter disposed on the gas guiding channels. The gas guiding channels serve as channels for supporting and transporting gas, and the several flame nozzles are distributed on them to ensure that the heat-conducting sand disposed above can be heated uniformly over a large area.

[0013] Compared with the prior art, the advantages of this utility model are: This invention uses a magnetic suction component to suspend and attract the welded pipe, allowing it to be flexibly moved along the support component. This completely solves the problem of difficult movement and placement of large-diameter pipes. In addition to a conventional heating mechanism below the weld, a compensating heating element that moves synchronously with the magnetic suction component is added directly above the weld. This enables simultaneous heating of both sides of the weld, effectively eliminating the temperature gradient and deformation stress caused by unilateral preheating. The temperature rise variation is small, effectively suppressing uneven thermal expansion and contraction deformation, thereby improving preheating uniformity, reducing subsequent welding defects, and ensuring efficient transfer and process stability. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the overall structure of the preheating device for large-diameter straight seam welded pipes in an embodiment. Figure 2 This is a schematic diagram of the supporting component and magnetic suction component of the preheating device for large-diameter straight seam welded pipe in an embodiment. Figure 3 for Figure 2 Enlarged view of point A; Figure 4 This is a schematic diagram of the container and heat source assembly of the preheating device for large-diameter straight seam welded pipes, as shown in the embodiment. Figure 5 This is a schematic diagram of the heat source assembly structure of the preheating device for large-diameter straight seam welded pipes, as shown in the embodiment.

[0016] Legend 1. Straight seam welded pipe; 2. Weld seam heating mechanism; 21. Container; 22. Heat source assembly; 221. Gas duct; 222. Flame nozzle; 223. Igniter; 23. Shaping assembly; 3. Load-bearing assembly; 31. Gantry frame; 311. Slide rail; 4. Magnetic assembly; 41. Sliding crossbar; 411. Slider; 42. Magnetic component; 421. Groove; 43. Lifting drive assembly; 431. Lifting drive component; 44. Long strip mounting base; 5. Heating element. Detailed Implementation

[0017] To facilitate understanding of this utility model, it will be described more comprehensively and in detail below with reference to the accompanying drawings and preferred embodiments. However, the scope of protection of this utility model is not limited to the following specific embodiments.

[0018] It should be noted that when a component is described as being "fixed to, attached to, connected to or connected to" another component, it can be directly fixed to, attached to, connected to or connected to the other component, or it can be indirectly fixed to, attached to, connected to or connected to the other component through other intermediate connectors.

[0019] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of protection of this invention.

[0020] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0021] Example: like Figures 1 to 5 As shown, the large-diameter straight seam welded pipe preheating device of this embodiment includes a weld heating mechanism 2 for preheating the downward-facing area of ​​the weld seam of the straight seam welded pipe 1, a bearing component 3 disposed above the weld heating mechanism 2, a magnetic suction component 4 for transferring the straight seam welded pipe 1, and a heating element 5 for heating the area directly above the weld seam of the straight seam welded pipe 1. The heating element 5 is disposed on the magnetic suction component 4, and the magnetic suction component 4 is movably disposed on the bearing component 3.

[0022] In this embodiment, as Figure 2 As shown, the bearing assembly 3 includes a set of gantry frames 31 spaced apart along the length of the straight seam welded pipe 1. The gantry frames 31 span above the weld heating mechanism 2. The magnetic suction assembly 4 is arranged along the length of the straight seam welded pipe 1 and is horizontally movable on the gantry frames 31 along the width of the straight seam welded pipe 1.

[0023] In this embodiment, the magnetic suction assembly 4 includes a sliding crossbeam 41 and a magnetic suction element 42 arranged along the length of the straight seam welded pipe 1. The sliding crossbeam 41 is horizontally movable along the width of the straight seam welded pipe 1 and is mounted on the gantry frame 31. The magnetic suction element 42 is vertically movable below the sliding crossbeam 41 via a lifting drive assembly 43. The heating element 5 is attached to the upper surface of the magnetic suction element 42 along the length of the straight seam welded pipe 1. The lower end of the sliding crossbeam 41 is provided with reinforcing ribs to further improve the strength of the sliding crossbeam 41 and prevent the sliding crossbeam 41 from deforming and failing due to excessive weight of the suspended object during operation.

[0024] In this embodiment, as Figure 3 As shown, the upper surface of the magnetic suction component 42 has a groove 421 along the length of the straight seam welded pipe 1. The heating element 5 consists of multiple heating cables arranged along the length of the straight seam welded pipe 1, which are attached to the groove 421. The magnetic suction component 42 is a flexible magnet, which can better fit the steel pipe and achieve better heating effect.

[0025] In this embodiment, the upper end face of the gantry frame 31 is provided with a slide rail 311 along the width direction of the straight seam welded pipe 1, and the two ends of the sliding cross frame 41 are respectively provided with sliders 411 for sliding back and forth on the slide rail 311.

[0026] In this embodiment, the lifting drive assembly 43 includes four vertically and evenly spaced lifting drive members 431. A long strip-shaped mounting base 44, arranged along the length of the straight seam welded pipe 1, is fixedly connected to the lower end of each lifting drive member 431. A heating element 5 and a magnetic suction member 42 are located at the lower end of the long strip-shaped mounting base 44. The lengths of the long strip-shaped mounting base 44, the heating element 5, and the magnetic suction member 42 are the same as the length of the straight seam welded pipe 1. In other embodiments, the number of lifting drive members 431 can be set according to the length of the magnetic suction member 42.

[0027] In this embodiment, as Figure 1 and Figure 4 As shown, the weld heating mechanism 2 includes a container 21 with an open top and filled with heat-conducting sand, and a heat source assembly 22 located below the container 21 for heating the heat-conducting sand. The straight seam welded pipe 1 is positioned with the weld seam facing downwards on the heat-conducting sand.

[0028] In this embodiment, the weld heating mechanism 2 also includes a shaping component 23 for creating an arc-shaped pit on the top surface of the heat-conducting sand pile. By creating the arc-shaped pit through the shaping component 23, it can better fit the curved surface where the weld of the straight seam welded pipe 1 is located, so that the heat can be transferred to the weld area more evenly.

[0029] In this embodiment, as Figure 5 As shown, the heat source assembly 22 includes four gas guide channels 221 arranged along the length of the straight seam welded pipe 1, a plurality of flame nozzles 222 disposed on the gas guide channels 221, and igniters 223 disposed on the gas guide channels 221. In other embodiments, the number of gas guide channels 221 may be set according to the specifications of the container 21.

[0030] In this embodiment, the specific operation steps include adjusting the straight seam welded pipe 1 to be preheated so that the weld seam faces downward, then conveying the straight seam welded pipe 1 to be preheated between the two gantry frames 31 through the conveying roller, and stopping it on one side of the container 21. At the same time, the heat source component 22 is turned on to heat the heat-conducting sand in the container 21. After reaching the preheating temperature, the magnetic suction component 42 moves horizontally to directly above the straight seam welded pipe 1, and the lifting drive component 43 adsorbs the straight seam welded pipe 1 to be preheated. Then, it continues to move and place the straight seam welded pipe 1 to be preheated in the container 21. The heat-conducting sand preheats the weld seam, and at the same time, the area directly above the magnetic suction component 42 is preheated through the heating cable. After the preheating is completed, the magnetic suction component 42 moves the preheated straight seam welded pipe 1 to the conveying roller on the other side of the container 21, and the preheated straight seam welded pipe 1 is conveyed to the subsequent process through the conveying roller.

[0031] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A preheating device for large-diameter straight seam welded pipes, comprising a weld heating mechanism (2) for preheating the weld-facing area of ​​the straight seam welded pipe (1), characterized in that, It also includes a support assembly (3) disposed above the weld heating mechanism (2), a magnetic suction assembly (4) for transferring the straight seam welded pipe (1), and a heating element (5) for heating the area directly above the weld of the straight seam welded pipe (1). The heating element (5) is disposed on the magnetic suction assembly (4), and the magnetic suction assembly (4) is movably disposed on the support assembly (3). The bearing component (3) includes a set of gantry frames (31) spaced apart along the length of the straight seam welded pipe (1). The gantry frames (31) span above the weld heating mechanism (2). The magnetic suction component (4) is arranged along the length of the straight seam welded pipe (1) and is horizontally movable along the width of the straight seam welded pipe (1) on the gantry frames (31). The magnetic suction assembly (4) includes a sliding crossbeam (41) and a magnetic suction element (42) arranged along the length direction of the straight seam welded pipe (1). The sliding crossbeam (41) is horizontally movable along the width direction of the straight seam welded pipe (1) and is arranged on the gantry frame (31). The magnetic suction element (42) is vertically movable below the sliding crossbeam (41) through a lifting drive assembly (43). The heating element (5) is attached to the upper end face of the magnetic suction element (42) along the length direction of the straight seam welded pipe (1). The magnetic suction component (42) has a groove (421) along the length of the straight seam welded pipe (1) on its upper end surface. The heating element (5) consists of multiple heating cables arranged along the length of the straight seam welded pipe (1) and the heating cables are attached to the groove (421).

2. The preheating device for large-diameter straight seam welded pipes according to claim 1, characterized in that, The upper end face of the gantry frame (31) is provided with a slide rail (311) along the width direction of the straight seam welded pipe (1), and the two ends of the sliding cross frame (41) are respectively provided with sliders (411) for sliding back and forth on the slide rail (311).

3. The preheating device for large-diameter straight seam welded pipes according to claim 1, characterized in that, The lifting drive assembly (43) includes a plurality of vertically and evenly spaced lifting drive components (431). The lower end of the lifting drive component (431) is fixed to a long strip mounting base (44) arranged along the length direction of the straight seam welded pipe (1). The heating element (5) and the magnetic suction component (42) are located at the lower end of the long strip mounting base (44).

4. The preheating device for large-diameter straight seam welded pipes according to any one of claims 1-3, characterized in that, The weld heating mechanism (2) includes a container (21) with an open top and filled with heat-conducting sand, and a heat source assembly (22) located below the container (21) for heating the heat-conducting sand. The straight seam welded pipe (1) is located on the heat-conducting sand with the weld seam facing downward.

5. The preheating device for large-diameter straight seam welded pipes according to claim 4, characterized in that, The heat source assembly (22) includes a plurality of gas guide channels (221) arranged along the length of the straight seam welded pipe (1), a plurality of flame nozzles (222) arranged on the gas guide channels (221), and an igniter (223) arranged on the gas guide channels (221).

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