Automatic welding gun head for pipe butt welding in narrow space

Abstract

The application discloses a kind of narrow space pipe pipe butt welding seam automatic welding gun head and method, comprising the following steps: step 1: electric heating element sleeve is adjusted to vertical position;Step 2: welding gun head top connects welding machine head, and the bottom of welding gun head is inserted from the maximum gap of adjacent two electric heating element sleeves vertically;Step 3: adjust the center of rotation of welding machine head to coincide with the center of electric heating element sleeve;Step 4: assemble electric heating element sleeve and connecting piece, and the tungsten electrode of welding gun head is aligned with the groove center between electric heating element sleeve and connecting piece, and three points are spot welded along the circumferential groove of welding gun head;Step 5: then automatic argon arc welding is carried out using welding gun head, and the weld of electric heating element sleeve and connecting piece is welded;Step 6: after welding, welding gun head is moved to the above next electric heating element sleeve, and steps 1-5 are repeated, to complete the narrow space pipe pipe welding of all electric heating element sleeves and connecting pieces.

Description

Technical Field

[0001] This invention belongs to the field of nuclear safety equipment voltage regulator manufacturing technology, specifically relating to an automated welding gun head for pipe-to-pipe butt welds in confined spaces. Background Technology

[0002] The pressurizer is a Class 1 nuclear safety device. It is a vertical cylindrical pressure vessel, with the main body made of low-alloy steel 16MND5 or 508-III. The inner wall, where it contacts the medium, is overlaid with austenitic stainless steel. It has a design pressure of 17.23 MPa and a design temperature of 360°C. This device is used to control pressure changes in the primary loop of the reactor system. During normal operation, it stabilizes the primary loop working pressure and provides overpressure protection in the event of an accident. The pressurizer is equipped with an electric heater and a spray system. When the primary loop pressure is higher than normal, the spray system sprays cold water from the top of the device to reduce the pressure; when the primary loop pressure is lower than normal, the electric heating elements at the bottom of the device automatically heat the water to evaporate and increase the pressure.

[0003] A certain type of voltage regulator is equipped with 180 electric heating elements. The sleeves and connectors of the electric heating elements need to be welded. The weld is a pipe-to-pipe joint. The weld must be fully penetrated and pass the radiographic test. The weld reinforcement must not exceed 0.5mm. After welding, the electric heating elements should be able to pass smoothly through the electric heating element sleeves and connectors.

[0004] The 180 electric heating elements are arranged in a triangle on the equipment cylinder, with a center-to-center distance of 65mm between adjacent elements. The outer diameter of the heating element sleeve is 45mm, the outer diameter of the connector is 22mm, and the minimum spacing between sleeves is 34mm. The operating space during welding is extremely limited. To ensure welding quality, wire-adding TIG welding must be used. When using manual TIG welding, welding can only be performed in all positions, resulting in a thicker weld layer. Due to weld shrinkage, the axis of the connector will deviate towards the side welded first after welding, preventing the heating elements from passing through the heating element sleeve and connector assembly. Furthermore, the limited operating space makes observation and operation during welding difficult, demanding high weld skill levels and making it challenging to guarantee weld quality.

[0005] To address the welding problems mentioned above, the aim is to develop an automated welding technology that, while ensuring weld quality, reduces the skill requirements for welders and effectively controls welding deformation. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide an automated welding gun head for pipe butt welds in confined spaces, which solves the welding problem of the weld between the sleeve of a voltage regulator electric heating element and the connector.

[0007] To solve the technical problem, the technical method of the present invention is: an automated welding method for pipe butt welds in confined spaces, comprising the following steps:

[0008] Step 1: Adjust the electric heating element sleeve to a vertical position;

[0009] Step 2: Connect the welding gun head to the top of the welding gun head, and insert the bottom of the welding gun head vertically into the part with the largest gap between the two adjacent electric heating element sleeves;

[0010] Step 3: Adjust the rotation center of the welding head to coincide with the center of the electric heating element sleeve;

[0011] Step 4: Assemble the electric heating element sleeve and connector. Align the tungsten electrode of the welding gun tip with the center of the bevel between the electric heating element sleeve and connector, and use the welding gun tip to evenly spot weld three points along the circumference of the bevel.

[0012] Step 5: Next, use the welding torch to perform automatic argon arc welding to weld the weld between the electric heating element sleeve and the connector;

[0013] Step 6: After welding, move the welding torch above the next electric heating element sleeve and repeat steps 1 to 5 to complete the welding of all electric heating element sleeves and connectors in the narrow space.

[0014] Preferably, step 1 specifically involves: placing the voltage regulator cylinder on the roller frame, installing the electric heating element sleeve 1 on the voltage regulator cylinder, and adjusting the electric heating element sleeve to a vertical position by rotating the voltage regulator cylinder.

[0015] Preferably, step 2 specifically includes:

[0016] Step 2-1: Connect the welding gun head to the top of the welding gun head and adjust the welding gun head to a vertically downward position;

[0017] Step 2-2: Move the welding head directly above the electric heating element sleeve, aligning the center of the welding head with the center of the electric heating element sleeve to achieve initial alignment;

[0018] Steps 2-3: Insert the bottom of the welding torch vertically into the widest gap between the two adjacent electric heating element sleeves.

[0019] Preferably, step 3 specifically involves: rotating the welding torch head so that the tip of the tungsten electrode makes random contact points on the outer circumference of the electric heating element sleeve, and using the center-finding program built into the welding head to make the rotation center of the welding torch head coincide with the center of the electric heating element sleeve, thus achieving final alignment.

[0020] Preferably, step 4 specifically includes:

[0021] Step 4-1: Install the connector on the top of the electric heating element sleeve, making the center of the connector coincide with the center of the electric heating element sleeve, and adjust the misalignment and bevel gap.

[0022] Step 4-2: Adjust the position of the welding torch so that the tungsten electrode of the welding torch is at the same horizontal height as the center of the bevel;

[0023] Step 4-3: Use a welding torch to perform manual spot welding, evenly distributing three spot welds along the circumference of the bevel.

[0024] Preferably, an automated welding torch for butt welds of pipes in confined spaces includes a welding torch, a welding torch fixing plate, a welding torch connecting plate, a welding torch connector assembly, a wire feeding guide assembly, an insulating jacket, and welding wire. One end of the welding torch is connected to the welding torch fixing plate, which is fixed to the welding torch connecting plate. The welding torch connecting plate is connected to the welding head. The insulating jacket is fitted onto the welding torch, and the other end of the welding torch is coaxially connected to the welding torch connector assembly. The wire feeding guide assembly is mounted on the insulating jacket. One end of the welding wire is wound around the wire feeding mechanism of the welding head, and the other end of the welding wire is pushed to the wire feeding nozzle at the front end of the welding torch through the wire feeding guide assembly. A tungsten electrode is installed on the welding torch connector assembly, with the axis of the tungsten electrode perpendicular to the axis of the welding torch connector assembly. The tungsten electrode is in contact with the welding torch and the welding head to achieve conductive connection for welding current. The angle between the tungsten electrode and the wire feeding nozzle of the wire feeding guide assembly is 45°.

[0025] Preferably, the insulating sleeve includes a hexagonal socket head cap screw, a fixing rod, a first wire feed tube fixing block, a first insulating sleeve, a second wire feed tube fixing block, a second insulating sleeve, a third insulating sleeve, an insulating clamping block, a movable block, a cylindrical nut, a movable seat, a fourth insulating sleeve, and a third hexagonal socket head cap screw. The first wire feed tube fixing block, the first insulating sleeve, the second wire feed tube fixing block, the second insulating sleeve, the third insulating sleeve, the insulating clamping block, and the fourth insulating sleeve are sequentially fitted onto the welding torch. The insulating clamping block has a welding torch mounting hole and a nut mounting hole in its center. The movable block and the movable seat are installed in the welding torch mounting hole. The component also passes through the welding torch mounting hole. The movable block and the moving seat are used to clamp the welding torch and the wire feeding guide component. The cylindrical nut is installed in the nut mounting hole. The third internal hexagon head screw is pressed against the welding torch through the radial threaded hole of the cylindrical nut, which indirectly realizes that the movable block and the moving seat hold the wire feeding guide component. The first wire feeding tube fixing block and the second wire feeding tube fixing block are fastened by internal hexagon head recessed set screws passing through the radial threaded hole of the fixing rod, thereby realizing the fixing of the wire feeding guide component on the first wire feeding tube fixing block and the second wire feeding tube fixing block, ensuring the direction and position of the wire feeding nozzle of the wire feeding guide component during the wire feeding process.

[0026] Preferably, the wire feeding guide assembly includes a wire feeding nozzle, a first wire guide tube, a wire feeding tube clamping block, a second wire guide tube, and a wire feeding tube transition sleeve. The wire feeding nozzle is connected to the first wire guide tube, the first wire guide tube is connected to the wire feeding tube clamping block, the wire feeding tube clamping block is connected to the second wire guide tube, the second wire guide tube is connected to the wire feeding tube transition sleeve, and the wire feeding tube transition sleeve is connected to the wire feeding mechanism. The welding wire is fed to the wire feeding nozzle at the front end of the welding gun head through the wire feeding tube transition sleeve, the second wire guide tube, the wire feeding tube clamping block, and the first wire guide tube. The wire feeding tube clamping block is mounted on the second wire feeding tube fixing block.

[0027] Preferably, a plug is installed at the end of the welding torch away from the welding torch connector assembly, the welding torch is fixedly connected to the welding torch fixing plate and the welding torch connecting plate by a first hexagon socket head cap screw and a second hexagon socket head cap screw, and the welding torch is fixedly connected to the welding torch connector assembly by a cylindrical pin.

[0028] Preferably, the diameter of the welding wire is 0.8 mm, the welding torch is made of copper, and the welding torch is provided with a cooling water circulation channel and an argon gas delivery channel inside.

[0029] Compared with the prior art, the advantages of the present invention are as follows:

[0030] (1) This invention discloses an automated welding gun head and method for pipe butt welds in narrow spaces. In view of the characteristics of pipe welding structure in narrow spaces, a set of special welding gun heads is designed and manufactured to realize automated welding of welds, which ensures the quality of welds and effectively solves the problem of weld deformation.

[0031] (2) In view of the structural characteristics of the weld between the electric heating element sleeve and the connector of the voltage regulator, the present invention adopts the vertical position of the axis of the electric heating element sleeve and the connector for welding. At this time, the welding position of the weld is the horizontal welding position, which can ensure that the weld thickness and welding parameters are consistent when the weld is welded for one revolution, thereby reducing the degree of axis deviation. During welding, the workpiece is fixed and the welding gun head rotates continuously around the connector to achieve welding.

[0032] (3) The welding torch structure of the welding torch head designed in this invention is slender and compact, and it is covered with an insulating jacket. The insulating jacket is equipped with a wire feeding guide assembly. During welding, the electric heating element sleeve is first adjusted to a vertical position. Then, the welding torch head is vertically inserted from the gap between adjacent electric heating element sleeves. The welding head is adjusted so that the rotation center of the welding torch head is concentric with the center of the electric heating element sleeve or the connecting part to ensure concentricity. At the same time, the tungsten electrode on the welding torch head is perpendicular to the weld and three spot welds are evenly distributed along the circumference of the weld. Then, automatic argon arc welding is performed under the control of the welding program to complete the welding and improve the welding efficiency.

[0033] (4) The present invention designs a welding torch. The welding torch of the welding torch is made of copper and has good conductivity. An insulating jacket is fitted on the outside of the welding torch to avoid the risk of surface “discharge” between the welding torch and the workpiece, which would damage the workpiece and the welding torch. A wire feeding guide assembly is installed on the insulating jacket to feed the welding wire during the welding process. The welding torch can also realize the functions of conveying argon gas and forced cooling of the welding torch. The overall structure is compact and reasonable. Attached Figure Description

[0034] Figure 1 A process flow diagram of an automated welding method for pipe-to-pipe butt welds in a confined space according to the present invention;

[0035] Figure 2 A schematic diagram illustrating the use of an automated welding torch for butt welds of pipes in confined spaces according to the present invention;

[0036] Figure 3 A schematic diagram of the overall structure of an automated welding gun head for pipe butt welds in confined spaces according to the present invention;

[0037] Figure 4 Exploded view of an automated welding torch for pipe butt welds in confined spaces according to the present invention.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1. Electric heating element sleeve; 2. Welding gun head; 3. Welding machine head; 4. Connecting parts; 5. Voltage stabilizer cylinder; 6. Weld seam.

[0040] 2-1 Welding torch, 2-2 Plug, 2-3 First hex socket head cap screw, 2-4 Second hex socket head cap screw, 2-5 Welding torch fixing plate, 2-6 Welding torch connecting plate, 2-7 Cylindrical pin, 2-8 Welding torch connector assembly, 2-9 Hex socket head cap set screw, 2-10 Fixing rod, 2-11 First wire feed tube fixing block, 2-12 First insulating sleeve, 2-13 Second wire feed tube fixing block, 2-1 4. Second insulating sleeve; 2-15. Third insulating sleeve; 2-16. Insulating clamping block; 2-17. Movable block; 2-18. Cylindrical nut; 2-19. Moving seat; 2-20. Fourth insulating sleeve; 2-21. Third internal hexagon socket head cap screw; 2-22. Welding wire; 2-23. Wire feed nozzle; 2-24. First wire guide tube; 2-25. Wire feed tube clamping block; 2-26. Second wire guide tube; 2-27. Wire guide tube transition sleeve.

[0041] 2-8-1, Tungsten electrode;

[0042] 2-16-1 Welding torch mounting hole; 2-16-2 Nut mounting hole. Detailed Implementation

[0043] The specific implementation of the present invention is described below with reference to embodiments:

[0044] It should be noted that the contents shown in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the principles, features and contents disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Without affecting the effects and objectives that the present invention can produce, all contents should still fall within the scope of the technical content disclosed in the present invention.

[0045] Example 1

[0046] like Figure 1 , 2 As shown, this invention discloses an automated welding method for pipe-to-pipe butt welds in confined spaces, comprising the following steps:

[0047] Step 1: Adjust the electric heating element sleeve 1 (sleeve) to a vertical position;

[0048] Step 2: Connect the top of the welding gun head 2 to the welding head 3, and insert the bottom of the welding gun head 2 vertically from the maximum gap between the two adjacent electric heating element sleeves 1;

[0049] Step 3: Adjust the rotation center of the welding head 3 to coincide with the center of the electric heating element sleeve 1;

[0050] Step 4: Assemble the electric heating element sleeve 1 and the connector 4. Align the tungsten electrode 2-8-1 of the welding gun head 2 with the center of the bevel between the electric heating element sleeve 1 and the connector 4. Use the welding gun head 2 to evenly spot weld three points along the circumference of the bevel.

[0051] Step 5: Next, use welding torch 2 to perform automatic argon arc welding to weld the weld 6 between the electric heating element sleeve 1 and the connector 4;

[0052] Step 6: After welding, move the welding torch 2 to the next electric heating element sleeve 1, and repeat steps 1 to 5 to complete the welding of all electric heating element sleeves 1 and connectors 4 in the narrow space.

[0053] In the method of the present invention, the electric heating element sleeve 1 and the connector 4 are welded in the vertical position of the axis. At this time, the welding position of the weld 6 is the horizontal welding position, which can ensure that the weld thickness and welding parameters are consistent when the weld is welded for one revolution, thereby reducing the degree of axis deviation. During welding, the workpiece is fixed and the welding gun head 2 rotates continuously around the connector 4 to achieve welding.

[0054] Example 2

[0055] Preferably, step 1 specifically involves: placing the voltage regulator cylinder 5 on the roller frame, installing the electric heating element sleeve 1 on the voltage regulator cylinder 5, and adjusting the electric heating element sleeve 1 to a vertical position by rotating the voltage regulator cylinder 5.

[0056] Preferably, step 2 specifically includes:

[0057] Step 2-1: Connect the welding gun head 3 to the top of the welding gun head 2, and adjust the welding gun head 2 to a vertically downward position;

[0058] Step 2-2: Move the welding head 3 directly above the electric heating element sleeve 1, aligning the center of the welding head 3 with the center of the electric heating element sleeve 1 to achieve initial alignment;

[0059] Steps 2-3: Insert the bottom of the welding gun head 2 vertically into the largest gap between the two adjacent electric heating element sleeves 1.

[0060] Example 3

[0061] Preferably, step 3 specifically involves rotating the welding torch head 2 so that the tip of the tungsten electrode 2-8-1 randomly contacts 3 points on the outer circumference of the electric heating element sleeve 1. The center of rotation of the welding torch head 2 is made to coincide with the center of the electric heating element sleeve 1 through the center-finding program built into the welding head 3, thus achieving final alignment.

[0062] The center-finding procedure is existing technology and will not be described in detail in this patent.

[0063] Preferably, step 4 specifically includes:

[0064] Step 4-1: Install connector 4 on the top of electric heating element sleeve 1, so that the center of connector 4 coincides with the center of electric heating element sleeve 1, and adjust the misalignment and bevel gap.

[0065] Step 4-2: Adjust the position of the welding gun head 2 so that the tungsten electrode 2-8-1 of the welding gun head 2 is at the same horizontal height as the center of the bevel;

[0066] Step 4-3: Use welding gun head 2 to perform manual spot welding, and evenly distribute three spot welds along the circumference of the bevel.

[0067] Example 4

[0068] Preferred, such as Figure 3 , 4As shown, this invention discloses an automated welding torch head for pipe butt welds in confined spaces. The welding torch head 2 includes a welding torch 2-1, a welding torch fixing plate 2-5, a welding torch connecting plate 2-6, a welding torch connector assembly 2-8, a wire feeding guide assembly, an insulating jacket, and welding wire 2-22. One end of the welding torch 2-1 is connected to the welding torch fixing plate 2-5, which is fixed to the welding torch connecting plate 2-6. The welding torch connecting plate 2-6 is connected to the welding head 3. The insulating jacket is fitted onto the welding torch 2-1, and the other end of the welding torch 2-1 is coaxially connected to the welding torch connector assembly 2-8. The wire feeding guide assembly... The guide assembly is installed on the insulating jacket. One end of the welding wire 2-22 is wound around the wire feeding mechanism of the welding head 3, and the other end of the welding wire 2-22 is pushed to the wire feeding nozzle 2-23 at the front end of the welding torch head 2 through the wire feeding guide assembly. A tungsten electrode 2-8-1 is installed on the welding torch connector assembly 2-8. The axis of the tungsten electrode 2-8-1 is perpendicular to the axis of the welding torch connector assembly 2-8. The tungsten electrode 2-8-1 is in contact with the welding torch 2-1 and the welding head 3 to achieve conductive connection of welding current. The included angle between the tungsten electrode 2-8-1 and the wire feeding nozzle 2-23 of the wire feeding guide assembly is 45°.

[0069] The welding torch of this invention allows for vertical insertion from the gap between adjacent electric heating element sleeves 1, with the rotation center of the welding torch concentric with the center of the electric heating element sleeve 1. Simultaneously, this welding torch also provides electrical conductivity, insulation, argon gas delivery, welding wire feeding, and forced cooling functions, resulting in a compact and rational welding torch structure.

[0070] The welding torch connecting plate 2-6 is made of insulating material to ensure insulation between the welding torch 2-1 and the welding manipulator.

[0071] The insulating jacket is fitted onto the welding torch 2-1 to prevent the metal components in the welding torch 2-1 from generating an electric arc with the workpiece during the welding process. The various parts of the insulating jacket are connected and fixed together by fitting and threading.

[0072] Example 5

[0073] Preferred, such as Figure 3 , 4As shown, the insulating sleeve includes a hexagonal socket head cap screw 2-9, a fixing rod 2-10, a first wire feed tube fixing block 2-11, a first insulating sleeve 2-12, a second wire feed tube fixing block 2-13, a second insulating sleeve 2-14, a third insulating sleeve 2-15, an insulating clamping block 2-16, a movable block 2-17, a cylindrical nut 2-18, a movable seat 2-19, a fourth insulating sleeve 2-20, and a third hexagonal socket head cap screw 2-21. The first wire feed tube fixing block 2-11, the first insulating sleeve 2-12, the second wire feed tube fixing block 2-13, the second insulating sleeve 2-14, the third insulating sleeve 2-15, the insulating clamping block 2-16, and the fourth insulating sleeve 2-20 are sequentially fitted onto the welding torch 2-1. The insulating clamping block 2-16 has a welding torch mounting hole 2-16-1 and a nut mounting hole 2-16-2 in its center. The movable block 2-17 and the movable seat... 2-19 is installed in the welding torch mounting hole 2-16-1, and the wire feeding guide assembly also passes through the welding torch mounting hole 2-16-1. The movable block 2-17 and the movable seat 2-19 are used to clamp the welding torch 2-1 and the wire feeding guide assembly. The cylindrical nut 2-18 is installed in the nut mounting hole 2-16-2. The third internal hexagonal head screw 2-21 is pressed against the welding torch 2-1 through the radial threaded hole of the cylindrical nut 2-18, indirectly realizing that the movable block 2-17 and the movable seat 2-19 hold the wire feeding guide assembly. The first wire feeding tube fixing block 2-11 and the second wire feeding tube fixing block 2-13 are fastened through the internal hexagonal head recessed set screw 2-9 through the radial threaded hole of the fixing rod 2-10, thereby realizing the fixing of the wire feeding guide assembly on the first wire feeding tube fixing block 2-11 and the second wire feeding tube fixing block 2-13, ensuring the direction and position of the wire feeding nozzle 2-23 during the wire feeding process.

[0074] Example 6

[0075] Preferred, such as Figure 3 , 4 As shown, the wire feeding guide assembly includes a wire feeding nozzle 2-23, a first wire guide tube 2-24, a wire feeding tube clamping block 2-25, a second wire guide tube 2-26, and a wire guide tube transition sleeve 2-27. The wire feeding nozzle 2-23 is connected to the first wire guide tube 2-24, the first wire guide tube 2-24 is connected to the wire feeding tube clamping block 2-25, the wire feeding tube clamping block 2-25 is connected to the second wire guide tube 2-26, the second wire guide tube 2-26 is connected to the wire guide tube transition sleeve 2-27, and the wire guide tube transition sleeve 2-27 is connected to the wire feeding mechanism. The welding wire 2-22 is fed to the wire feeding nozzle 2-23 at the front end of the welding gun head 2 through the wire guide tube transition sleeve 2-27, the second wire guide tube 2-26, the wire feeding tube clamping block 2-25, and the first wire guide tube 2-24. The wire feeding tube clamping block 2-25 is mounted on the second wire feeding tube fixing block 2-13.

[0076] Example 7

[0077] Preferred, such as Figure 3 ,4 As shown, a plug 2-2 is installed at the end of the welding torch 2-1 away from the welding torch connector assembly 2-8. The welding torch 2-1 is fixedly connected to the welding torch fixing plate 2-5 and the welding torch connecting plate 2-6 by the first internal hexagonal head screw 2-3 and the second internal hexagonal head screw 2-4. The welding torch 2-1 is fixedly connected to the welding torch connector assembly 2-8 by the cylindrical pin 2-7.

[0078] Preferably, the diameter of the welding wire 2-22 is 0.8 mm, the welding torch 2-1 is made of copper, and the welding torch 2-1 is provided with a cooling water circulation channel and an argon gas delivery channel inside.

[0079] To reduce welding deformation, the thickness of each weld layer is reduced by using a smaller welding wire diameter. Considering the bending resistance and bending radius when welding wire 2-22 is fed, this invention selects a welding wire with a diameter of 0.8mm.

[0080] To ensure that the welding wire 2-22 is fed, the welding wire 2-22 is fed from the wire feeding mechanism fixed on the welding head through the wire guide tube on the welding gun head 2 to the wire feeding nozzle 2-23 at the front end of the welding gun head 2, and then fed into the molten pool through the wire feeding nozzle 2-23.

[0081] The welding torch 2-1 is equipped with a cooling water circulation channel and an argon gas delivery channel, which can realize the water cooling protection, argon gas delivery and electrical conductivity of the welding torch, so as to ensure that the temperature rise of the welding torch head 2 is controlled within a reasonable range during the welding process.

[0082] Example 8

[0083] Step 1: Place the voltage regulator cylinder 5 on the roller frame, and adjust the electric heating element sleeve 1 to the vertical position of the axis by rotating the voltage regulator cylinder 5;

[0084] Step 2: Adjust the welding head 3 to a vertically downward position;

[0085] Move the welding head 3 directly above the electric heating element sleeve 1, and roughly align the center of the welding head 3 with the center of the electric heating element sleeve 1 to achieve initial alignment.

[0086] Insert the welding gun head 2 vertically from the larger gap between the two sleeves until the tungsten electrode 2-8-1 of the welding gun head 2 is at the same horizontal height as the center of the bevel.

[0087] Step 3: By rotating the welding gun head 2, the tip of the tungsten electrode 2-8-1 is randomly contacted at 3 points on the outer circle of the sleeve. The center of rotation of the welding gun head 2 is made concentric with the center of the electric heating element sleeve 1 by the center-finding program built into the welding head 3.

[0088] Step 4: Assemble connector 4 and electric heating element sleeve 1. After adjusting the misalignment and bevel gap, use welding gun head 2 to manually spot weld three weld points evenly distributed along the circumference.

[0089] Step 5: After adjusting the height of tungsten electrode 2-8-1, start the automatic welding program to weld;

[0090] Step 6: After completing one weld, raise the welding torch 2 from the gap of the connector 4 and move it to the next weld 6, repeating the above welding process.

[0091] The welding method of this invention has improved the pass rate of radiographic testing of 180 electric heating element sleeves and connectors welds in a single product from 85% to 100%, shortened the welding production cycle from 30 days to 10 days, and effectively controlled the straightness requirements of the electric heating element sleeves and connectors after welding, avoiding post-weld straightening.

[0092] The principle of this invention is as follows:

[0093] This invention discloses a solution for automated welding of pipe-to-pipe butt welds under confined and narrow space conditions. By designing a slender and compact welding torch 2, it realizes the functions of insulation, protective gas delivery, welding wire feeding, welding current conduction, and water cooling of the welding torch during the welding process. Through the cooperation of the welding torch 2 and the automated welding head 3, the automated argon arc welding of pipe-to-pipe butt welds is realized, which effectively solves the problems of low efficiency, high welding operation difficulty, low non-destructive testing pass rate of welds, and pipe axis deviation after welding in manual argon arc welding of pipe-to-pipe butt welds.

[0094] This invention discloses an automated welding torch and method for butt welds of pipes in confined spaces. Targeting the welding characteristics of pipe welding structures in confined spaces, a set of specialized welding torches is designed and manufactured to achieve automated welding of the welds, ensuring weld quality while effectively solving the problem of weld deformation.

[0095] This invention addresses the structural characteristics of the weld between the electric heating element sleeve and the connector in a voltage regulator. It employs welding the electric heating element sleeve and the connector in a vertical position along their axes, while the weld position is horizontal. This ensures that the weld thickness and welding parameters are consistent throughout the weld rotation, thereby reducing the degree of axial misalignment. During welding, the workpiece is fixed, and the welding torch rotates continuously around the connector to achieve the welding process.

[0096] The welding torch designed in this invention has a slender and compact structure, and is covered with an insulating jacket. The insulating jacket is equipped with a wire feeding guide assembly. During welding, the electric heating element sleeve is first adjusted to a vertical position. Then, the welding torch is vertically inserted into the gap between adjacent electric heating element sleeves. The welding head is adjusted so that the rotation center of the welding torch is concentric with the center of the electric heating element sleeve or the connecting part, ensuring concentricity. At the same time, the tungsten electrode on the welding torch is perpendicular to the weld seam, and three spot welds are evenly distributed along the circumference of the weld seam. Then, automatic argon arc welding is performed under the control of the welding program to complete the welding, thus improving welding efficiency.

[0097] This invention designs a welding torch, the welding torch of which is made of copper and has good conductivity. The outside of the welding torch is covered with an insulating jacket to avoid the risk of surface "discharge" between the welding torch and the workpiece, which would damage the workpiece and the welding torch. The insulating jacket is equipped with a wire feeding guide assembly for feeding the welding wire during the welding process. The welding torch can also realize the functions of conveying argon gas and forced cooling of the welding torch. The overall structure is compact and reasonable.

[0098] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by ordinary geologists in the art, various changes can be made without departing from the spirit of the present invention.

[0099] Many other changes and modifications can be made without departing from the concept and scope of this invention. It should be understood that this invention is not limited to the specific embodiments, and the scope of this invention is defined by the appended claims.

Claims

1. An automated welding torch for butt welds of pipes in confined spaces, characterized in that: The welding torch head (2) includes a welding torch (2-1), a welding torch fixing plate (2-5), a welding torch connecting plate (2-6), a welding torch connector assembly (2-8), a wire feeding guide assembly, an insulating jacket, and welding wire (2-22). One end of the welding torch (2-1) is connected to the welding torch fixing plate (2-5), which is fixed on the welding torch connecting plate (2-6). The welding torch connecting plate (2-6) is connected to the welding head (3). The insulating jacket is fitted onto the welding torch (2-1), and the other end of the welding torch (2-1) is coaxially connected to the welding torch connector assembly (2-8). The welding torch head assembly (2-8) has a wire feeding guide assembly mounted on an insulating jacket. One end of the welding wire (2-22) is wound around the wire feeding mechanism of the welding torch head (3), and the other end of the welding wire (2-22) is pushed to the wire feeding nozzle (2-23) at the front end of the welding torch head (2) via the wire feeding guide assembly. A tungsten electrode (2-8-1) is mounted on the welding torch head assembly (2-8). The axis of the tungsten electrode (2-8-1) is perpendicular to the axis of the welding torch head assembly (2-8). The tungsten electrode (2-8-1) is perpendicular to the axis of the welding torch head assembly (2-8). The welding current is conductively connected via an inter-contact connection. The angle between the tungsten electrode (2-8-1) and the wire feed nozzle (2-23) of the wire feed guide assembly is 45°. The wire feed guide assembly includes a wire feed nozzle (2-23), a first wire guide tube (2-24), a wire feed tube clamping block (2-25), a second wire guide tube (2-26), and a wire feed tube transition sleeve (2-27). The wire feed nozzle (2-23) is connected to the first wire guide tube (2-24), and the first wire guide tube (2-24) is connected to the wire feed tube clamping block (2-25). Block (2-25) is connected to the second wire guide tube (2-26), the second wire guide tube (2-26) is connected to the wire guide tube transition sleeve (2-27), the wire guide tube transition sleeve (2-27) is connected to the wire feeding mechanism, the welding wire (2-22) is fed to the wire feeding nozzle (2-23) at the front end of the welding gun head (2) through the wire guide tube transition sleeve (2-27), the second wire guide tube (2-26), the wire feeding tube clamping block (2-25) and the first wire guide tube (2-24), and the wire feeding tube clamping block (2-25) is installed on the second wire feeding tube fixing block (2-13).

2. The automated welding torch for butt welds of pipes in confined spaces according to claim 1, characterized in that: The insulating sleeve includes a hexagon socket head cap screw (2-9), a fixing rod (2-10), a first wire feed tube fixing block (2-11), a first insulating sleeve (2-12), a second wire feed tube fixing block (2-13), a second insulating sleeve (2-14), a third insulating sleeve (2-15), an insulating clamping block (2-16), a movable block (2-17), a cylindrical nut (2-18), a movable seat (2-19), a fourth insulating sleeve (2-20), and a third hexagon socket head cap screw (2-10). 21) The first wire feeding tube fixing block (2-11), the first insulating sleeve (2-12), the second wire feeding tube fixing block (2-13), the second insulating sleeve (2-14), the third insulating sleeve (2-15), the insulating clamping block (2-16), and the fourth insulating sleeve (2-20) are sequentially fitted onto the welding torch (2-1). The insulating clamping block (2-16) has a welding torch mounting hole (2-16-1) and a nut mounting hole (2-16-2) in its center. The movable block (2-17) and the moving seat are also included. (2-19) is installed in the torch mounting hole (2-16-1). The wire feeding guide assembly also passes through the torch mounting hole (2-16-1). The movable block (2-17) and the movable seat (2-19) are used to clamp the torch (2-1) and the wire feeding guide assembly. The cylindrical nut (2-18) is installed in the nut mounting hole (2-16-2). The third internal hexagonal head screw (2-21) is tightened onto the torch (2-1) through the radial threaded hole of the cylindrical nut (2-18), indirectly realizing the movement. Block (2-17) and movable seat (2-19) hold the wire feeding guide assembly tightly; the first wire feeding tube fixing block (2-11) and the second wire feeding tube fixing block (2-13) are fastened by internal hexagonal recessed set screws (2-9) passing through the threaded holes on the radial side of the fixing rod (2-10), thereby fixing the wire feeding guide assembly on the first wire feeding tube fixing block (2-11) and the second wire feeding tube fixing block (2-13), ensuring the direction and position of the wire feeding nozzle (2-23) of the wire feeding guide assembly during the wire feeding process.

3. The automated welding torch for butt welds of pipes in confined spaces according to claim 1, characterized in that: A plug (2-2) is installed at the end of the welding torch (2-1) away from the welding torch connector assembly (2-8). The welding torch (2-1) is fixedly connected to the welding torch fixing plate (2-5) and the welding torch connecting plate (2-6) by a first hexagon socket head cap screw (2-3) and a second hexagon socket head cap screw (2-4). The welding torch (2-1) is fixedly connected to the welding torch connector assembly (2-8) by a cylindrical pin (2-7).

4. The automated welding torch for butt welds of pipes in confined spaces according to claim 1, characterized in that: The diameter of the welding wire (2-22) is 0.8 mm, and the welding torch (2-1) is made of copper. The welding torch (2-1) is equipped with a cooling water circulation channel and an argon gas delivery channel inside.

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