Underwater oxyacetylene flame preheating integrated welding gun device
By integrating the underwater oxy-acetylene flame preheating welding torch with the wire feeding torch and the oxy-acetylene flame torch, the problem of cumbersome operation of underwater welding preheating devices has been solved, realizing an efficient and convenient welding process and improving welding quality and adaptability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- QINGDAO HARBIN INSTITUTE OF TECHNOLOGY (WEIHAI)
- Filing Date
- 2026-04-10
- Publication Date
- 2026-05-12
AI Technical Summary
Existing underwater welding equipment has preheating devices that are difficult to use effectively, and the operation is cumbersome, inconvenient, and lacks flexibility, resulting in poor welding quality.
Design an integrated underwater oxyacetylene flame preheating welding torch device, which integrates a wire feeding welding torch and an oxyacetylene flame torch. Preheating is achieved by mixing oxygen and acetylene gases to form a flame. A water stop valve is used to ensure the stability of the gas circuit system. The distance and angle between the nozzle and the torch head are optimized to achieve continuous preheating and welding.
It achieves effective preheating of the underwater welding area, improves welding quality and work efficiency, simplifies the operation process, enhances the flexibility and safety of the equipment, and adapts to different welding scenarios and material requirements.
Smart Images
Figure CN122015090A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of underwater welding technology, and more specifically, to an integrated underwater oxyacetylene flame preheating welding torch device. Background Technology
[0002] With the continuous development of underwater welding technology, underwater welding has been widely used in marine engineering, ship repair, and deep-sea pipeline maintenance. However, due to the special underwater environment, the water cooling effect has a negative impact on welding quality. Water is a strong cooling medium, causing heat to dissipate rapidly.
[0003] In order to reduce the negative impact of water cooling on welding quality, those skilled in the art have taken some measures, such as electric arc heating. However, the electric arc heat source is difficult to effectively heat the weld area, resulting in insufficient heat input during the welding process, excessively rapid cooling of the weld, and easy generation of cracks, porosity and welding defects.
[0004] For example, referring to the utility model patent with authorization announcement number CN210334835U, a three-layer drainage cover system including a preheating system is disclosed. This system creates a low-pressure or dry zone in the welding space and controls the welding conditions. Its key feature is the integration of drainage, venting, and preheating functions to construct a more complete on-site weld area environment. However, the preheating device has a complex structure and requires separate installation during the pre-welding preparation stage. The installation process is cumbersome, demonstrating that this preheating device is not simple to implement. Furthermore, the preheating device lacks flexibility and adaptability to different welding scenarios. Summary of the Invention
[0005] This application aims to solve the technical problems of existing underwater welding equipment's preheating devices being difficult to preheat effectively, having cumbersome operation, poor ease of use, and poor flexibility. It provides an integrated underwater oxy-acetylene flame preheating welding torch device that can achieve effective preheating, is easy to operate, and improves welding quality.
[0006] This application provides an integrated underwater oxyacetylene flame preheating welding torch device, including a shell, an end cap, a wire feeding welding torch and an oxyacetylene flame torch. The end cap is connected to the lower end of the shell, and the wire feeding welding torch and the oxyacetylene flame torch are respectively connected to the shell. The wire feeding welding torch and the oxyacetylene flame torch are arranged side by side. The wire feeding welding gun includes a wire feeding channel and a gun head. The gun head is connected to the wire feeding channel. The end of the gun head is provided with a wire guide nozzle. The lower part of the wire feeding channel passes through the end cap. A sealing element is provided at the connection between the lower part of the wire feeding channel and the end cap. The upper part of the wire feeding channel passes through the upper end of the housing. A sealing element is provided at the connection between the upper part of the wire feeding channel and the upper end of the housing. The oxy-acetylene flame gun includes an oxygen pipe, an acetylene pipe, an oxygen gun tube, an acetylene gun tube, a sealing connector, and a nozzle. The oxygen gun tube and the acetylene gun tube are fixedly connected to the housing and arranged longitudinally side by side. The oxygen pipe is connected to the upper end of the oxygen gun tube through a sealing connector, and the acetylene pipe is connected to the upper end of the acetylene gun tube through a sealing connector. The nozzle is connected to an end cap, and a seal is provided at the connection between the nozzle and the end cap. The lower ends of the oxygen gun tube and the acetylene gun tube are respectively connected to the nozzle. The nozzle has a first input channel, a second input channel, and an output channel. The outlet of the first input channel is connected to the output channel, and the outlet of the second input channel is connected to the output channel. The lower end of the oxygen gun tube is connected to the inlet of the first input channel of the nozzle, and the lower end of the acetylene gun tube is connected to the inlet of the second input channel of the nozzle. The nozzle is arranged adjacent to the gun head.
[0007] Preferably, a stop valve is connected to the lower part of the oxygen gun barrel, and a stop valve is connected to the lower part of the acetylene gun barrel.
[0008] Preferably, the angle α between the axis of the nozzle head and the normal to the surface of the workpiece to be welded is 30° to 45°, and the angle β between the axis of the nozzle and the normal to the surface of the workpiece to be welded is 20° to 35°.
[0009] Preferably, the distance L between the nozzle and the end of the welding torch head is 10-25 mm.
[0010] Preferably, the sealing element at the connection between the lower part of the wire feeding channel and the end cover is a sealing ring.
[0011] Preferably, the seal at the connection between the nozzle and the end cap is a sealing ring.
[0012] Preferably, the underwater oxyacetylene flame preheating integrated welding torch device further includes a mounting clamp, which is connected to the upper end of the housing.
[0013] The beneficial effects of this application are that it effectively preheats the area to be welded, allowing preheating and welding to be continuously connected in a spatially adjacent area, thus improving the quality of underwater welding; it also increases work efficiency, saving time and costs; and it enhances operational convenience. At the same time, it also ensures safety.
[0014] It enhances welding applicability and adaptability, allowing for flame temperature adjustment to meet diverse welding needs, accommodating various materials and thicknesses, and improving versatility. Furthermore, it is suitable for various underwater operating environments, providing reliable welding performance in deep sea, high-pressure waters, and specialized underwater maintenance environments.
[0015] It is highly flexible in use and adaptable to different welding scenarios.
[0016] Further features and aspects of the present invention will be clearly described in the following detailed description with reference to the accompanying drawings. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of an integrated underwater oxyacetylene flame preheating welding torch device. Figure 2 This is an internal structural diagram of an integrated underwater oxy-acetylene flame preheating welding torch device. Figure 3 It is an assembly structure diagram of a wire-feeding welding torch and an oxy-acetylene torch. Figure 4 This is a schematic diagram of the water stop valve. Figure 5 This is a schematic diagram showing the angle between the axis of the gun head and the normal to the workpiece surface; Figure 6 This is a diagram illustrating the distance between the gun head and the nozzle; Figure 7 This is a schematic diagram of the underwater oxyacetylene flame preheating integrated welding torch device relative to the workpiece's movement direction.
[0018] Explanation of symbols in the diagram: 1. Wire feeding welding torch, 101. Torch head, 102. Welding wire, 103. First sealing ring, 104. Wire guide nozzle; 2. Oxyacetylene torch, 201. Oxygen pipe, 202. Acetylene pipe, 203. Oxygen torch barrel, 204. Acetylene torch barrel, 205. Water stop valve, 2051. Valve body, 2052. Valve core, 2053. Spring, 2054. Sealing valve seat, 206. Second sealing ring, 207. Nozzle, 2071. First input channel, 2072. Second input channel, 2073. Output channel, 208. Sealing joint; 3. Housing, 4. Mounting clamp, 5. End cap; 6. Workpiece. Detailed Implementation
[0019] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0020] The specific embodiments described below are merely preferred embodiments of this application, and the scope of protection of this application is not limited thereto. Those skilled in the art can make modifications or variations based on the principles, concepts, and spirit of this application, and the resulting technical solutions should all be covered within the scope of protection of this application.
[0021] like Figures 1-4 As shown, the underwater oxyacetylene flame preheating integrated welding torch device includes a housing 3, an end cap 5, a wire feeding welding torch 1, an oxyacetylene flame torch 2, and a mounting clamp 4. The wire feeding welding torch 1 and the oxyacetylene flame torch 2 are respectively connected to the housing 3.
[0022] The housing 3 is a hollow cylindrical structure, and the end cap 5 is fixedly connected to the lower end of the housing 3. The wire-feeding welding torch 1 and the oxy-acetylene flame torch 2 are installed inside the housing 3, arranged side by side, with their lower ends extending from the end cap 5. The wire-feeding welding torch 1 outputs welding wire and performs preheating of the oxy-acetylene flame on the same device, forming an integrated structure with tight connection between preheating and welding. The mounting clamp 4 is connected to the upper end of the housing 3 and is used to connect to an external working support or handheld fixing mechanism, thereby positioning the entire underwater oxy-acetylene flame preheating integrated welding torch device. The connection between the end cap 5 and the housing 3 can be achieved through a threaded structure with a sealing ring or sealant at the connection point; or it can be a stop structure with a sealing ring or sealant at the connection point.
[0023] The wire feeding welding gun 1 includes a wire feeding channel and a gun head 101. The wire feeding channel is the main body of the wire feeding welding gun 1. The gun head 101 is connected to the wire feeding channel. The lower part of the wire feeding channel passes through the end cap 5, causing the gun head 101 to extend downward from the end cap 5. The wire guide nozzle 104 is connected to the end of the gun head 101. The welding wire 102 is introduced into the wire feeding channel of the wire feeding welding gun 1 from top to bottom and finally exited by the wire guide nozzle 104. A first sealing ring 103 is set at the connection between the lower part of the wire feeding channel and the end cap 5 to achieve a seal, thereby reducing the impact of the underwater environment on the stability of wire feeding and welding. Alternatively, the connection between the lower part of the wire feeding channel and the end cap 5 can be made with sealant instead of the first sealing ring 103. The upper end of the housing 3 is completely closed. The upper part of the wire feeding channel of the wire feeding welding gun 1 passes through the upper end of the housing 3. A sealing ring or sealant is provided at the connection between the upper part of the wire feeding channel and the upper end of the housing 3. This ensures that the wire feeding welding torch 1 maintains a stable relative position and prevents water from entering during underwater operation.
[0024] Regarding the gas path of the oxyacetylene flame gun 2, oxygen pipe 201 and acetylene pipe 202 are located at the upper part of the device. Oxygen pipe 201 is used to connect to an external oxygen cylinder, and acetylene pipe 202 is used to connect to an external acetylene cylinder. Oxygen is supplied through the external oxygen cylinder via oxygen pipe 201, and acetylene is supplied through the external acetylene cylinder, thereby regulating the oxyacetylene flame. The ratio of oxygen to acetylene can be controlled to 1:1.0~1.2. Oxygen gun tube 203 and acetylene gun tube 204 are respectively fixed in grooves inside the housing 3, arranged longitudinally side by side. Two sealing joints 208 are located at the upper end of the housing 3, and the two sealing joints 208 are respectively connected to the upper ends of oxygen gun tube 203 and acetylene gun tube 204. Oxygen pipe 201 and acetylene pipe 202 are connected to two sealing joints 208, respectively. Specifically, the oxygen pipe 201 is connected to the oxygen gun tube 203 via the sealing joints 208, and the acetylene pipe 202 is connected to the acetylene gun tube 204 via the sealing joints 208. The sealing rings in the sealing joints 208 should preferably be made of fluororubber, which is resistant to oil, temperature, and seawater. The nozzle 207 is connected to the end cap 5. A second sealing ring 206 is provided at the connection point between the nozzle 207 and the end cap 5 to achieve a seal and improve the underwater adaptability of the gas system. The lower ends of the oxygen gun tube 203 and the acetylene gun tube 204 are connected to the nozzle 207, ensuring a stable relative position for the oxyacetylene flame gun 2 under underwater conditions and preventing water ingress. The nozzle 207 has a first input channel 2071, a second input channel 2072, and an output channel 2073. The outlet of the first input channel 2071 is connected to the output channel 2073, and the outlet of the second input channel 2072 is connected to the output channel 2073, forming a three-way structure. The lower end of the oxygen gun tube 203 is connected to the inlet of the first input channel 2071 of the nozzle 207, and the lower end of the acetylene gun tube 204 is connected to the inlet of the second input channel 2072 of the nozzle 207. The oxygen gun tube 203 and the acetylene gun tube 204 deliver the two gases to the oxyacetylene flame gun nozzle 207 for mixed combustion and injection. To avoid gas path instability or even safety risks due to backflow or water ingress during underwater operations, a water stop valve 205 is provided at the lower part of the oxygen gun tube 203 and the acetylene gun tube 204.
[0025] The specific structure of the stop valve 205 can adopt a one-way check structure suitable for underwater gas transportation environments (such as...). Figure 4As shown, it includes a valve body 2051, a valve core 2052, a spring 2053, and a sealing valve seat 2054. The sealing valve seat 2054 is connected to the valve body 2051, and the valve core 2052 is connected and cooperates with the sealing valve seat 2054. The valve body 2051 has a fluid channel inside, and the valve core 2052 is located within the fluid channel and connected to the spring 2053. One end of the spring 2053 abuts against the inner wall of the valve body 2051, and the other end abuts against the valve core 2052, so that the valve core 2052 is in a closed state when there is no gas pressure. When oxygen or acetylene enters from the gas source, the gas pressure pushes the valve core 2052 to move downstream against the elastic force of the spring 2053, opening the fluid channel and allowing gas to pass smoothly. When the gas supply is interrupted or external water pressure attempts to reinject, the valve core 2052 quickly returns to the sealing valve seat position under the combined action of the spring's restoring force and the external water pressure, thereby closing the fluid channel and preventing water from entering the gas system. This structure effectively prevents backflow and water ingress in underwater environments, improving the stability and safety of the gas path system. Its operation is as follows: when gas is supplied forward, the valve core opens under pressure, allowing gas to pass smoothly; when external water pressure returns or the gas supply is momentarily interrupted, the valve core quickly closes under the combined action of spring force and water pressure, thereby blocking water from entering the gas path and suppressing the risk of backflow. This ensures the stability and safety of the oxyacetylene flame under underwater conditions.
[0026] This invention provides an integrated underwater oxyacetylene flame preheating welding torch device with a mounting clamp 4 providing an installation reference for the housing 3. A wire-feeding welding torch 1 extends through the housing 3, with welding wire 102 fed from above. The torch 1 has a wire feeding channel and outputs through a guide nozzle 104. An oxyacetylene flame torch 2 also extends from top to bottom. The wire-feeding torch 1 and the oxyacetylene flame torch 2 form a stable parallel structure within the housing 3. The torch head 101 and nozzle 207 maintain a fixed relative position in space, ensuring the preheating flame continuously acts on the adjacent area in front of the weld, achieving preheating before welding. The integration of the oxyacetylene flame torch 2 and the wire-feeding torch 1 makes the distance and relative position between preheating and welding stable and controllable. This reduces the problems of existing underwater operations where the preheating device and welding torch are separated, resulting in heat being carried away by the water before it can be transferred, slow operation switching, and large positioning deviations. This also suppresses the rapid heat dissipation caused by strong water cooling and increases the initial temperature of the welding zone.
[0027] To ensure effective coverage of the welding zone by the preheating flame and avoid disturbance caused by direct flame impact on the molten pool, the angle between the lower exit directions of the wire-feeding torch 1 and the oxy-acetylene torch 2 during welding, and the angle α between the axis of the torch head 101 and the normal to the surface of the workpiece to be welded, should be 30°–45°; the angle β between the axis of the nozzle 207 of the oxy-acetylene torch and the normal to the surface of the workpiece to be welded should be 20°–35°, and the nozzle 207 should be pointed towards the area in front of the welding direction to form preheating. The nozzle 207 and the torch head 101 are arranged adjacent to each other with a certain distance between them. The distance L between the ends of the nozzle 207 and the torch head 101 should be 10–25 mm; the distance between the flame point of the nozzle 207 and the point where the welding wire enters the pool along the welding direction should be 10–30 mm, so that the temperature rise in the preheating zone is sufficient but the molten pool becomes unstable. The above angles and distances can be adjusted according to the water flow rate, welding depth, and base material thickness: when the water flow is greater, the base material is thicker, or the heat dissipation is stronger, the distance between the nozzle and the workpiece can be appropriately reduced and the preheating distance can be slightly increased to improve the effective heat input; when the molten pool is easily disturbed, the distance between the nozzle and the end of the welding torch can be increased or the nozzle angle can be reduced to reduce flame impact.
[0028] Regarding the materials of each component, the nozzle 101 of the wire-feeding welding torch should preferably be made of heat-resistant and corrosion-resistant copper alloy to balance thermal conductivity and wear resistance; the wire guide nozzle 104 should preferably be made of wear-resistant and conductive copper material to reduce wear and maintain stable wire feeding; the housing 3 and the mounting clamp 4 should preferably be made of 304 stainless steel to adapt to underwater corrosive environments; the oxygen gun tube 203 and the acetylene gun tube 204 should preferably be made of thin-walled stainless steel tubes to balance pressure resistance, corrosion resistance, and structural strength; the nozzle 207 can be made of heat-resistant copper alloy; the valve body of the stop valve 205 should preferably be made of stainless steel, and the valve core and seat can be made of wear-resistant and corrosion-resistant materials to ensure long-term check valve reliability. The first sealing ring 103 and the second sealing ring 206 should preferably be made of fluororubber that is oil-resistant, temperature-resistant, and resistant to seawater media.
[0029] Regarding ignition and operation sequence, to improve underwater safety and flame stability, the specific operation is as follows: During ignition, first turn on the acetylene gas source and slightly adjust the acetylene gas flow rate, while simultaneously turning on a small amount of oxygen gas source, so that the acetylene gas and oxygen form a combustible mixture at the outlet of the nozzle 207's output channel 2073. Then, use the underwater ignition device to generate ignition energy near the nozzle 207 outlet, igniting the combustible mixture and forming an initial flame. After ignition, gradually adjust the oxygen and acetylene supply to stabilize the flame combustion state, and adjust the flame to a neutral flame or a slightly acetylene-rich flame according to welding process requirements to achieve stable preheating of the area to be welded. During the preheating stage, first direct the flame towards the area to be welded to heat it until the welding area reaches the set temperature rise or a stable preheating state, then activate the external wire feeding structure to allow the welding wire 102 to be output from the wire guide nozzle 104 via the wire feeding welding gun 1 for welding, according to... Figure 7In the direction indicated by the middle arrow, nozzle 207 is in front and gun head 101 is behind. The preheating and welding steps are performed sequentially, and the flame can be kept continuously preheating the welding area during the welding process, achieving a continuous "preheating-welding" connection. Alternatively, after the oxyacetylene flame stabilizes, the operator controls the device to move along the welding direction, ensuring that nozzle 207 is always in front of the welding direction, while gun head 101 is positioned a certain distance behind it. During the device movement, the oxyacetylene flame emitted from nozzle 207 continuously heats the area in front of the welding area in real time, maintaining a high initial temperature for the area to be welded; simultaneously, the wire feeder 1 outputs welding wire 102 and forms a weld pool. Because a fixed distance L (10-25mm) is maintained between nozzle 207 and gun head 101, a stable spatial interval is formed between the flame preheating zone and the weld pool, thus achieving a continuous operation process of preheating and welding simultaneously. This synchronous operation method can continuously compensate for heat loss caused by water cooling during the welding process, improving the temperature stability of the welding area, thereby further improving the weld formation quality and microstructure. When welding needs to be paused, first stop wire feeding and lift the torch head 101, then maintain the flame at a low flame for a short time, or shut off the flame according to process requirements. During flameout, it is preferable to first close the oxygen pipe 201 to weaken and extinguish the flame, then close the acetylene pipe 202. Throughout the process, the water stop valve 205 automatically closes when external water pressure returns or the gas supply is interrupted to prevent water from entering the gas path, improving the reliability and safety of the device under water. After welding is completed, the nozzle 207 end, wire guide nozzle 104, and all sealing rings should be flushed and inspected. Replace sealing rings and vulnerable parts as necessary to maintain long-term stable operation of the device.
[0030] As can be seen, the underwater oxyacetylene flame preheating integrated welding torch device of the present invention effectively improves the quality of underwater welding. By employing oxyacetylene flame preheating, it overcomes the problem of excessively low welding zone temperature caused by water cooling during underwater welding, significantly reducing the negative impact of water cooling on welding quality. The oxyacetylene flame can provide sufficient heating to the welding surface during the welding process, effectively controlling the temperature of the weld zone and reducing quality problems such as cracks and porosity caused by excessively rapid welding cooling. By increasing the temperature of the welding zone, it ensures good fusion of welding materials, improving the strength and stability of the weld.
[0031] On the other hand, it improves work efficiency and saves time and costs. The integrated design combines welding and preheating functions into a single unit, reducing equipment disassembly and operation steps. This not only simplifies the operation process but also significantly improves welding efficiency. Direct preheating via an oxy-acetylene flame makes the welding process smoother, reducing equipment preparation time and energy consumption, thereby effectively saving construction time and costs.
[0032] On the other hand, to enhance ease of operation, an integrated design combines preheating and welding functions into a single device. This integrated design not only improves the stability of the equipment but also greatly simplifies the operation process, allowing operators to adjust and maintain it more conveniently. The compact design of the equipment makes it suitable for more complex underwater operating environments, especially in deep and flowing water where it offers greater flexibility.
[0033] On the other hand, to ensure the safety of the welding process, a water stop valve is installed to ensure safety, allowing for rapid closure in the event of gas supply interruption or external water pressure backflow. The arrangement of nozzle 207 and gun head 101 also ensures the safety of the welding process. Adjusting the gas flow rate of the oxyacetylene flame can provide a stable flame temperature, ensuring the safety of the welding process.
[0034] On the other hand, it enhances welding applicability and adaptability. The flame temperature can be adjusted according to different welding requirements, adapting to welding needs for various materials and thicknesses, thus improving versatility. Simultaneously, it is suitable for various underwater operating environments, providing reliable welding performance whether in deep sea, high-pressure waters, or special underwater maintenance environments.
[0035] The underwater oxyacetylene flame preheating integrated welding torch device of the present invention has been verified for reliability through a large number of experiments in different environments.
Claims
1. An integrated underwater oxyacetylene flame preheating welding torch device, characterized in that, It includes a housing, an end cap, a wire feeding welding torch, and an oxy-acetylene torch. The end cap is connected to the lower end of the housing, and the wire feeding welding torch and the oxy-acetylene torch are respectively connected to the housing. The wire feeding welding torch and the oxy-acetylene torch are arranged side by side. The wire feeding welding gun includes a wire feeding channel and a gun head. The gun head is connected to the wire feeding channel. The end of the gun head is provided with a wire guide nozzle. The lower part of the wire feeding channel passes through an end cap. A sealing element is provided at the connection between the lower part of the wire feeding channel and the end cap. The upper part of the wire feeding channel passes through the upper end of the housing. A sealing element is provided at the connection between the upper part of the wire feeding channel and the upper end of the housing. The oxyacetylene flame gun includes an oxygen pipe, an acetylene pipe, an oxygen gun tube, an acetylene gun tube, a sealing connector, and a nozzle. The oxygen gun tube and the acetylene gun tube are fixedly connected to the housing and arranged longitudinally side by side. The oxygen pipe is connected to the upper end of the oxygen gun tube through a sealing connector, and the acetylene pipe is connected to the upper end of the acetylene gun tube through a sealing connector. The nozzle is connected to an end cap, and a seal is provided at the connection between the nozzle and the end cap. The lower ends of the oxygen gun tube and the acetylene gun tube are respectively connected to the nozzle. The nozzle has a first input channel, a second input channel, and an output channel. The outlet of the first input channel is connected to the output channel, and the outlet of the second input channel is connected to the output channel. The lower end of the oxygen gun tube is connected to the inlet of the first input channel of the nozzle, and the lower end of the acetylene gun tube is connected to the inlet of the second input channel of the nozzle. The nozzle is arranged adjacent to the gun head.
2. The underwater oxyacetylene flame preheating integrated welding torch device according to claim 1, characterized in that, A stop valve is connected to the lower part of the oxygen gun barrel, and a stop valve is connected to the lower part of the acetylene gun barrel.
3. The underwater oxyacetylene flame preheating integrated welding torch device according to claim 1 or 2, characterized in that, The angle α between the axis of the nozzle and the normal to the surface of the workpiece to be welded is 30° to 45°, and the angle β between the axis of the nozzle and the normal to the surface of the workpiece to be welded is 20° to 35°.
4. The underwater oxyacetylene flame preheating integrated welding torch device according to claim 3, characterized in that, The distance L between the nozzle and the end of the welding torch head is 10-25 mm.
5. The underwater oxyacetylene flame preheating integrated welding torch device according to claim 1, characterized in that, The sealing element at the connection between the lower part of the wire feeding channel and the end cap is a sealing ring.
6. The underwater oxyacetylene flame preheating integrated welding torch device according to claim 1, characterized in that, The sealing element at the connection between the nozzle and the end cap is a sealing ring.
7. The underwater oxyacetylene flame preheating integrated welding torch device according to claim 1, characterized in that, The underwater oxyacetylene flame preheating integrated welding torch device also includes a mounting clamp, which is connected to the upper end of the housing.