Metal arc spot welding test device under high temperature and high pressure environment

Abstract

The application belongs to the field of extreme environment advanced manufacturing technology, and particularly relates to a metal electric arc spot welding experimental device under high temperature and high pressure environment. The device can simulate high pressure working conditions such as deep sea and deep well, and provides experimental means for process behavior and mechanism research of in-situ welding / repair of metal structure. The device is integrated by four systems: the high pressure cabin system is the core pressure bearing environment, the end cover and the multi-layer sealing structure are used to ensure the safety of high temperature and high pressure sealing; the safety system adopts the explosion-proof safety cabinet and the interlocking structure to ensure stable operation under extreme parameters; the environment control system integrates the gas source, pressurization, heating and vacuum pumping units to realize accurate control of the pressure and temperature in the cabin and atmosphere adjustment; the electric arc spot welding system contains a special welding gun, a high-voltage insulation lead-in mechanism and a welding machine, which can complete arc striking and spot welding under high pressure environment. The application makes up for the deficiency that traditional equipment cannot carry out spot welding research in high pressure environment, provides a special platform for exploring the influence of high pressure on arc, molten pool and weld quality, and has important supporting significance for the research and development of in-situ repair technology of deep sea equipment and underground facilities.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology in extreme environments, and more specifically to a metal arc spot welding test device under high temperature and high pressure conditions. Background Technology

[0002] In high-pressure extreme environments such as deep-sea oil and gas drilling and geothermal resource development, metal components are subjected to the combined effects of complex alternating loads and corrosive media for extended periods, making them prone to localized damage and performance degradation. Traditional repair processes typically require disassembling the components and returning them to the factory for further processing, which not only incurs high economic costs but also leads to prolonged system downtime, severely impacting project continuity and operational efficiency. Existing in-situ repair technologies, such as wet welding and mechanical connections, while possessing some engineering application foundation, still suffer from insufficient process stability and difficulty in controlling forming quality when implemented under high-pressure environments. In particular, the lack of methods for verifying the mechanical properties of repaired joints under real-world conditions severely restricts the development efficiency and reliability improvement of in-situ repair processes for high-pressure environments.

[0003] To overcome the aforementioned technical bottlenecks, there is an urgent need to develop specialized experimental equipment capable of accurately simulating high-pressure conditions in a laboratory environment, supporting preliminary research and performance evaluation of repair processes. This type of equipment must be able to complete standardized metal joining specimens under set pressure conditions, providing a crucial experimental platform for exploring the influence mechanism of pressure on welding metallurgical behavior and constructing stable process windows. Summary of the Invention

[0004] This invention aims to address the problems existing in the prior art and fill gaps in current research. Specifically, it addresses the difficulty in quantifying and evaluating the repair effectiveness of metal parts after in-situ welding / repair under high temperature and high pressure conditions using existing techniques. This invention provides a metal arc spot welding test device for high temperature and high pressure environments. This device can prepare standardized test samples under high temperature and high pressure conditions. Combined with other testing methods, it can easily obtain key data such as mechanical properties and microstructure, helping technicians quantify the actual effects of in-situ welding / repair of metal parts in engineering practice and contributing to the development of in-situ metal forming technology under special pressure.

[0005] This device is designed for the development of in-situ welding and repair processes for metal components in high-pressure environments, such as marine engineering equipment and geothermal drilling facilities, providing a key experimental and evaluation platform. Its core value lies in providing reliable high-pressure environment experimental methods for optimizing process parameters and evaluating joint performance, thereby significantly improving the R&D efficiency and technical confidence of high-pressure repair processes.

[0006] The technical solution adopted to achieve the above-mentioned objectives is as follows.

[0007] A metal arc spot welding test device under high temperature and high pressure environment includes a high-pressure chamber system, a safety system, an environmental control system, and an arc welding system. The high-pressure chamber system is a sealed pressure vessel structure, serving as the working chamber for the arc spot welding test and providing a set high-pressure environment for the spot welding process. The high-pressure chamber system integrates leveling components, overpressure protection components, and environmental parameter detection interfaces. The safety system is enclosed on the outside of the high-pressure chamber system and integrates high-frequency operation components for personnel safety protection and operational convenience during the test. The environmental control system is in a sealed connection with the high-pressure chamber system through a high-pressure pipeline, used to deliver protective fluid into the high-pressure chamber system and to precisely regulate and monitor the ambient temperature and pressure inside the high-pressure chamber system in real time to simulate environmental parameters under extreme conditions in the deep sea or deep earth. The welding execution end of the arc welding system is sealed and inserted through the top of the high-pressure chamber system, and its grounding end is stably electrically connected to the high-pressure chamber system, used to complete controllable metal arc spot welding operations under the high temperature and high pressure environment of the high-pressure chamber system, and prepare standardized welding samples that meet performance testing requirements.

[0008] The high-pressure chamber system includes a welding torch holder fixing plate, a welding torch holder, an insulating gasket, a high-pressure chamber upper cover, an upper ceramic insulating ring, a welding wire high-pressure sealing ring, a welding wire high-pressure sealing ring seat, a lower ceramic insulating ring, an upper high-pressure chamber sealing ring, a safety valve, a high-pressure chamber body, a lower high-pressure chamber sealing ring, a high-pressure chamber lower cover, and anchor bolts. The high-pressure chamber body is welded to an upper flange, a lower flange, and an intermediate cylinder. The upper flange is fixedly connected to the high-pressure chamber upper cover by bolts, and the lower flange is fixedly connected to the high-pressure chamber lower cover by bolts, together forming a sealed cavity. A sealing ring groove is formed on the mating surface of the upper flange and the high-pressure chamber upper cover, and the upper high-pressure chamber sealing ring is embedded in the sealing ring groove to achieve a static seal between them. A sealing ring groove is formed on the mating surface of the lower flange and the high-pressure chamber lower cover, and the lower high-pressure chamber sealing ring is embedded in the sealing ring groove to achieve a static seal between them. The outer wall of the intermediate cylinder has multiple threaded interfaces for connecting functional components and the environmental control system.

[0009] The upper cover of the high-pressure chamber has a centrally located axial shoulder hole for threading the welding wire and welding actuator. An upper ceramic insulating ring is press-fitted into the axial shoulder hole, and a high-pressure sealing ring for the welding wire is installed within the axial shoulder hole. A high-pressure sealing ring seat is threaded into the axial shoulder hole and presses against the welding wire high-pressure sealing ring to achieve dynamic sealing at the point where the welding wire passes through. A lower ceramic insulating ring is nested within the high-pressure sealing ring seat. Together, the upper and lower ceramic insulating rings form an insulating and protective structure between the welding actuator and the upper cover of the high-pressure chamber.

[0010] The welding torch holder is positioned and installed in the positioning groove on the upper end face of the high-pressure chamber's upper cover. The welding torch holder fixing plate is fixedly connected to the high-pressure chamber's upper cover by bolts and presses the welding torch holder to fix the welding execution end. The insulating gasket is placed between the contact surfaces of the welding torch holder and the high-pressure chamber's upper cover for insulation and isolation between the two. The safety valve is threadedly installed on the side wall interface of the high-pressure chamber body, forming the overpressure protection assembly for overpressure relief protection of the high-pressure chamber system. The anchor bolts are threadedly screwed onto the lower end cover of the high-pressure chamber, forming the leveling assembly for adjusting the levelness and overall fixation of the high-pressure chamber system.

[0011] The safety system includes a safety cabinet and a support frame; the safety cabinet covers the exterior of the hyperbaric chamber system, forming a physical protective structure for the testing process; the support frame is used to integrate and support small-sized, high-frequency operating components in the hyperbaric chamber system, safety system, and environmental control system.

[0012] The safety cabinet includes a top cover, a handle, a safety lock, a main body, and a base. The top cover is hinged to the top of the main body. The handle is bolted to the top surface of the top cover. A through hole is provided in the center of the top cover for inserting the welding actuator. The safety lock is installed at the opening / closing point of the top cover and the main body for locking them together. The bottom of the main body is bolted to the base. The base has threaded holes for securing the hyperbaric chamber system. A cable tray is provided at the bottom of the main body for running high-voltage pipelines and cables.

[0013] The environmental control system includes a gas cylinder, an air booster, a gas-driven booster pump, a pipeline heating device, an inlet needle valve, an inlet check valve, an outlet check valve, a temperature and pressure sensor, a paperless recorder, an outlet needle valve, a high-pressure three-way ball valve, and a vacuum pump.

[0014] The air-driven booster pump is equipped with a protective fluid inlet, a protective fluid outlet, and a driving air interface. The protective fluid inlet is connected to the outlet of a gas cylinder via a high-pressure pipeline. The gas cylinder is used to store the protective fluid required for arc spot welding. The driving air interface is connected to the outlet of an air booster via a compressed air hose. The air booster is used to provide the driving air source for the air-driven booster pump. The protective fluid outlet is connected to the inlet of the high-pressure chamber system via a high-pressure pipeline, which is sequentially connected to a pipeline heating device, an inlet needle valve, and an inlet check valve. The air-driven booster pump is used to pressurize the protective fluid output from the gas cylinder to a set pressure. The pipeline heating device is used to heat the protective fluid in the pipeline to regulate the ambient temperature inside the high-pressure chamber system. The inlet needle valve is used for fine-tuning the flow rate of the protective fluid. The inlet check valve is used to prevent fluid backflow within the high-pressure chamber system.

[0015] The outlet of the high-pressure chamber system is connected in sequence to an outlet check valve and an outlet needle valve via pipelines, and then connected to interface a of a high-pressure three-way ball valve; interface b of the high-pressure three-way ball valve is connected to a vacuum pump via a high-pressure pipeline, and interface c is connected to the atmosphere; the outlet check valve is used to prevent external gas from flowing back into the high-pressure chamber system, the outlet needle valve is used for fine adjustment of the exhaust flow rate, the high-pressure three-way ball valve is used to switch the on / off state of the gas path, and the vacuum pump is used to perform vacuum treatment inside the high-pressure chamber system before the test to ensure the purity of the protective fluid.

[0016] The temperature and pressure sensor is threaded onto the side wall interface of the high-pressure chamber system, forming the environmental parameter detection interface, which is used to collect temperature and pressure data inside the high-pressure chamber system in real time; the paperless recorder is electrically connected to the temperature and pressure sensor, and is used to store, display and output the collected temperature and pressure data in real time.

[0017] The arc welding system includes a welding machine, a grounding wire / cable holder, a welding torch, and a grounding clamp. The welding torch constitutes the welding execution end, and the grounding clamp constitutes the grounding end. The positive terminal of the welding machine is electrically connected to the welding torch via the cable, and the negative terminal is electrically connected to the grounding clamp via the grounding wire. The welding machine is used for precise control and recording of welding voltage, welding current, and wire feed speed during spot welding. The welding torch is fixedly installed on the welding torch holder of the high-pressure chamber system, with its nozzle end extending into the forming cavity of the high-pressure chamber system. The grounding clamp is stably clamped on the main body of the high-pressure chamber system to form a complete and safe welding current loop. The grounding wire / cable holder is used to fix and guide the cable and grounding wire. The arc welding system also integrates an automatic weld tracking module for precise positioning of the welding position and automatic tracking of the weld trajectory during spot welding.

[0018] The beneficial effects of the metal arc spot welding test device under high temperature and high pressure environment of the present invention are:

[0019] A dedicated experimental platform serving basic research and process pre-research in high-pressure welding has been established, filling a crucial gap in the transition from atmospheric pressure research to high-pressure applications. Existing technologies primarily develop welding processes under atmospheric pressure, and the resulting parameters and mechanistic understanding cannot be extrapolated to high-pressure environments. This invention, by integrating a high-pressure chamber, an environmental control system, and a dedicated arc welding system, is the first to construct a standardized experimental environment in the laboratory that can be precisely controlled and stably reproduced for deep-sea / deep-earth high-pressure environments. Researchers can systematically conduct high-pressure spot welding experiments on this platform and directly prepare standardized samples for subsequent analysis. This fundamentally solves the problem of lacking reliable pre-experimental methods for high-pressure welding process development, building a crucial bridge for the process to move from the laboratory to field applications.

[0020] This invention achieves experimental decoupling and mechanistic research on the intrinsic correlation mechanism of "pressure-process-performance". Traditional methods struggle to isolate the individual effects of pressure on the welding metallurgical process. By precisely controlling the core variable of environmental pressure, this invention supports researchers in systematically revealing the direct impact of pressure on fundamental processes such as arc stability, droplet transfer, molten pool solidification, and defect formation. Standardized samples prepared using this device can be subjected to detailed microstructure analysis and offline performance testing, thereby constructing a clear intrinsic correlation model of "pressure-process-microstructure-performance". This provides irreplaceable experimental evidence for understanding the high-pressure welding mechanism and predicting joint service behavior.

[0021] This device provides a direct and efficient verification method for the reliability assessment of in-situ repair technologies in deep-sea / deep-earth engineering. The core value of this device lies in its ability to advance the verification of repair processes to the laboratory stage. By fabricating spot welds in a simulated high-pressure environment and subjecting them to destructive testing, reliable welding process windows can be fully evaluated and screened before implementing high-cost, high-risk on-site repairs. This significantly reduces the technical and economic risks of in-situ repair operations in deep-sea oil and gas and geothermal development projects, providing crucial technical support for improving the maintenance and protection capabilities of metal structures in extreme environments. Attached Figure Description

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and specific implementation methods.

[0023] Figure 1 An isometric view of a metal arc spot welding test device under high temperature and high pressure conditions;

[0024] Figure 2 A front view of a metal arc spot welding test device under high temperature and high pressure environment;

[0025] Figure 3 A top view of a metal arc spot welding test device under high temperature and high pressure conditions;

[0026] Figure 4 Exploded view of the hyperbaric chamber system;

[0027] Figure 5 A structural view of the safety system;

[0028] Figure 6 This is a structural view of the environmental control system.

[0029] Figure 7 This is a structural view of an arc welding system;

[0030] In the diagram: High-pressure chamber system 1; Welding torch holder fixing plate 1.1; Welding torch holder 1.2; Insulating gasket 1.3; High-pressure chamber upper end cover 1.4; Upper ceramic insulating ring 1.5; Welding wire high-pressure sealing ring 1.6; Welding wire high-pressure sealing ring seat 1.7; Lower ceramic insulating ring 1.8; Upper high-pressure chamber sealing ring 1.9; Safety valve 1.10; High-pressure chamber body 1.11; Lower high-pressure chamber sealing ring 1.12; High-pressure chamber lower end cover 1.13; Anchor bolt 1.14;

[0031] Safety system 2; Safety cabinet 2.1; Safety cabinet top cover 2.1.1; Safety cabinet handle 2.1.2; Safety lock 2.1.3; Safety cabinet body 2.1.4; Safety cabinet base 2.1.5; Support 2.2;

[0032] 3. Environmental control system; 3.1. Gas cylinder; 3.2. Air booster; 3.3. Air-driven booster pump; 3.4. Pipeline heating device; 3.5. Inlet needle valve; 3.6. Inlet check valve; 3.7. Outlet check valve; 3.8. Temperature and pressure sensor; 3.9. Paperless recorder; 3.10. Outlet needle valve; 3.11. High-pressure three-way ball valve; 3.12. Vacuum pump;

[0033] 4. Arc welding system; 4.1 Welding machine; 4.2 Grounding wire / wiring wire bracket; 4.3 Welding torch; 4.4 Grounding clamp. Detailed Implementation

[0034] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Figure 1-3 This is a view of the overall structure of the device, attached. Figure 4 Exploded view of the hyperbaric chamber system, attached. Figure 5 For the structural view of the safety system, see attached. Figure 6 This is a structural view of the environmental control system, attached. Figure 7 This is a structural view of an arc welding system; those skilled in the art can clearly understand the structural composition, assembly relationship, and usage method of the present invention through this embodiment, and the scope of protection of the present invention is determined by the claims.

[0035] The present invention discloses a metal arc spot welding test device under high temperature and high pressure environment, which mainly consists of four parts: high pressure chamber system 1, safety system 2, environmental control system 3, and arc welding system 4. The specific structure, assembly relationship and function of each system are as follows:

[0036] I. Hyperbaric Chamber System 1

[0037] The high-pressure chamber system 1 is a sealed pressure vessel structure and is the core operating chamber for arc spot welding tests. It includes a welding torch holder fixing plate 1.1, a welding torch holder 1.2, an insulating gasket 1.3, a high-pressure chamber upper end cover 1.4, an upper ceramic insulating ring 1.5, a welding wire high-pressure sealing ring 1.6, a welding wire high-pressure sealing ring seat 1.7, a lower ceramic insulating ring 1.8, an upper high-pressure chamber sealing ring 1.9, a safety valve 1.10, a high-pressure chamber body 1.11, a lower high-pressure chamber sealing ring 1.12, a high-pressure chamber lower end cover 1.13, and anchor bolts 1.14. The assembly and function of each component are as follows:

[0038] The main body of the high-pressure chamber 1.11 is formed by welding the upper and lower flanges to the middle body. The upper flange is connected to the upper cover 1.4 of the high-pressure chamber by bolts. The flange face has a sealing ring groove for installing the upper high-pressure chamber sealing ring 1.9 to achieve static sealing between the two. The lower flange is connected to the lower cover 1.13 of the high-pressure chamber by bolts. The flange face has a sealing ring groove for installing the lower high-pressure chamber sealing ring 1.12 to achieve static sealing between the two. The outer wall of the middle body is provided with multiple threaded interfaces for connecting various functional components and the environmental control system 3. The hollow part is used as a spot-welded forming cavity.

[0039] The upper cover 1.4 of the high-pressure chamber has a central shoulder hole for threading welding wire. The upper ceramic insulating ring 1.5 is press-fitted into the shoulder hole, and the welding wire high-pressure sealing ring 1.6 is embedded in the hole and secured by the welding wire high-pressure sealing ring seat 1.7 to achieve dynamic sealing at the welding wire. The welding wire high-pressure sealing ring seat 1.7 is threaded into the shoulder hole, and the lower ceramic insulating ring 1.8 is nested inside it. The upper ceramic insulating ring 1.5 and the lower ceramic insulating ring 1.8 together provide insulation protection for the welding end.

[0040] The welding torch holder 1.2 is installed in the positioning groove on the upper end face of the high-pressure chamber upper cover 1.4 and is fixed by the welding torch holder fixing piece 1.1 with bolts. An insulating gasket 1.3 is placed between the welding torch holder 1.2 and the high-pressure chamber upper cover 1.4 to achieve insulation isolation. The welding torch holder 1.2 is used to support and fix the welding torch 4.3.

[0041] Safety valve 1.10 is threadedly installed on the side wall interface of the high-pressure chamber body 1.11 to realize overpressure protection of high-pressure chamber system 1; anchor bolt 1.14 is threadedly connected to the lower end cover 1.13 of the high-pressure chamber for overall leveling and fixing of high-pressure chamber system 1.

[0042] The lower end cover 1.13 of the high-pressure chamber is bolted to the lower end flange of the main body 1.11 of the high-pressure chamber, together forming a closed pressure vessel cavity, providing a high-pressure environment for spot welding tests.

[0043] II. Security System 2

[0044] Safety system 2 includes a safety cabinet 2.1 and a support frame 2.2. Its core function is to ensure personnel safety during the testing process, while also improving the ease of operation of the device. Its specific structure and functions are as follows:

[0045] The safety cabinet 2.1 includes a safety cabinet top cover 2.1.1, a safety cabinet handle 2.1.2, a safety lock 2.1.3, a safety cabinet body 2.1.4, and a safety cabinet base 2.1.5. The safety cabinet top cover 2.1.1 is hinged to the safety cabinet body 2.1.4, and the safety cabinet handle 2.1.2 is fixed to its top surface with bolts. A central through hole is provided for the welding torch 4.3 to pass through. The safety lock 2.1.3 is installed at the opening and closing point of the safety cabinet top cover 2.1.1 and the safety cabinet body 2.1.4 for locking and fixing the two together. The safety cabinet body 2.1.4 is connected to the safety cabinet base 2.1.5 with bolts. The lower end has a groove for protecting the fluid pipeline and the grounding wire. The safety cabinet base 2.1.5 has a threaded hole for fixing the high-pressure chamber system 1.

[0046] The bracket 2.2 is used to integrate and support small components with high opening and closing frequency in the hyperbaric chamber system 1, safety system 2, and environmental control system 3, so as to facilitate on-site operation by operators.

[0047] III. Environmental Control System 3

[0048] The environmental control system 3 includes a gas cylinder 3.1, an air booster 3.2, a gas-driven booster pump 3.3, a pipeline heating device 3.4, an inlet needle valve 3.5, an inlet check valve 3.6, an outlet check valve 3.7, a temperature and pressure sensor 3.8, a paperless recorder 3.9, an outlet needle valve 3.10, a high-pressure three-way ball valve 3.11, and a vacuum pump 3.12. Its core function is to regulate the temperature and pressure parameters within the hyperbaric chamber system 1, transport protective fluids, and achieve real-time monitoring of environmental parameters. The assembly and functions of each component are as follows:

[0049] Gas cylinder 3.1 is connected to the protective fluid inlet of air-driven booster pump 3.3 via a high-pressure pipeline to store the protective fluid required for arc spot welding; air booster 3.2 is connected to the drive air interface of air-driven booster pump 3.3 via a compressed air hose to provide drive air to air-driven booster pump 3.3; the protective fluid outlet of air-driven booster pump 3.3 is connected to inlet needle valve 3.5 via a high-pressure pipeline to pressurize the protective fluid output from gas cylinder 3.1 to the test set pressure.

[0050] The pipeline heating device 3.4 is installed on the bracket 2.2 and includes a temperature control module and a heating module. The heating module is wrapped around the high-pressure pipeline between the gas-driven booster pump 3.3, the protective fluid outlet, and the inlet needle valve 3.5. The temperature control module can set and adjust the heating temperature in real time, and achieve temperature control of the high-pressure chamber forming cavity by heating the protective fluid.

[0051] The inlet needle valve 3.5 is installed on the bracket 2.2. One end is connected to the air-driven booster pump 3.3, and the other end is connected to the inlet check valve 3.6 through a high-pressure pipeline for fine-tuning the flow rate of the protective fluid. The inlet check valve 3.6 is connected to the high-pressure chamber body 1.11 through a thread to prevent the protective fluid inside the high-pressure chamber system 1 from flowing back.

[0052] The outlet check valve 3.7 is connected to the high-pressure chamber body 1.11 by a thread. One end is connected to the inside of the high-pressure chamber, and the other end is connected to the outlet needle valve 3.10 through a high-pressure pipeline to prevent the experimental waste gas from flowing back. The outlet needle valve 3.10 is used to fine-tune the flow rate of the experimental waste gas, and its other end is connected to the interface a of the high-pressure three-way ball valve 3.11.

[0053] The high-pressure three-way ball valve 3.11 has its port b connected to the vacuum pump 3.12 via a high-pressure pipeline, and its port c is connected to the air, which can realize the switching of the gas path. The vacuum pump 3.12 is used to evacuate the air in the high-pressure chamber during the preparation stage of arc spot welding to ensure the purity of the protective fluid.

[0054] The temperature and pressure sensor 3.8 is connected to the high-pressure chamber body 1.11 via a thread, and can read the temperature and pressure parameters inside the high-pressure chamber in real time during the spot welding test; the paperless recorder 3.9 is installed on the bracket 2.2 and is electrically connected to the temperature and pressure sensor 3.8, and is used to store temperature and pressure data and present them in the form of charts.

[0055] IV. Arc Welding System 4

[0056] The arc welding system 4 includes a welding machine 4.1, a grounding wire / cable holder 4.2, a welding torch 4.3, and a grounding clamp 4.4. Its core function is to perform metal arc spot welding operations in the high-temperature and high-pressure environment of the high-pressure chamber system 1. The assembly and functions of each component are as follows:

[0057] The welding machine 4.1 connects the wire to the welding gun 4.3 and the grounding clamp 4.4 through the grounding wire, which can provide precise control of voltage and current for the welding process. At the same time, welding process parameters such as wire feed speed can be set and adjusted.

[0058] The welding torch 4.3 is installed on the welding torch holder 1.2 of the high-pressure chamber system 1. It is the execution end of the arc spot welding and can complete the spot welding operation in the high-pressure chamber forming cavity.

[0059] The grounding clamp 4.4 is held on the main body 1.11 of the high-voltage chamber, forming a complete and safe current circuit together with the welding machine 4.1 and the welding torch 4.3.

[0060] The grounding wire / cable holder 4.2 is used to fix and guide the cable and grounding wire to avoid the cable getting tangled and affecting the test operation.

[0061] V. Method of using the device of the present invention

[0062] The usage process of the device of this invention is divided into four steps: equipment assembly, experimental preparation, arc spot welding, and post-processing. The specific operations of each step are as follows:

[0063] (a) Equipment assembly stage

[0064] Based on the actual working conditions in deep sea and deep earth, the environmental parameters (pressure, temperature), welding process parameters (welding voltage, welding current, wire feed speed) and material parameters (material type, spot welding material size) of the test were determined.

[0065] Check the protective fluid level in gas cylinder 3.1 to ensure it meets the test requirements;

[0066] Loosen the fixing bolts of the upper cover 1.4 of the high-pressure chamber, install the forming platform and the part to be welded into the forming cavity of the main body 1.11 of the high-pressure chamber, and reset and fix the upper cover 1.4 of the high-pressure chamber.

[0067] Clamp the grounding clamp 4.4 into the designated position on the main body 1.11 of the high-voltage chamber, close the safety cabinet 2.1 and lock the safety lock 2.1.3, install and fix the welding torch 4.3 on the welding torch holder 1.2, and complete the overall assembly of the equipment.

[0068] (II) Experimental Preparation Stage

[0069] Open the outlet needle valve 3.10, adjust the high-pressure three-way ball valve 3.11 to connect interfaces a and b, and turn on the vacuum pump 3.12 to evacuate the air from inside the high-pressure chamber system 1.

[0070] Close the outlet needle valve 3.10, open the gas cylinder 3.1 and the inlet needle valve 3.5, and fill the high-pressure chamber system 1 with protective fluid. Repeat the vacuuming and filling of protective fluid operation until the purity of the protective fluid inside the high-pressure chamber system 1 meets the test requirements.

[0071] Based on the test pressure setting, adjust the output pressure of the air booster 3.2. Based on the test temperature setting, set the output temperature of the pipeline heating device 3.4 and preheat the high-pressure pipeline for 10 minutes to ensure temperature control accuracy.

[0072] (III) Arc spot welding process

[0073] On the welding machine 4.1, precisely set the process parameters such as welding current, welding voltage, and wire feed speed, open the inlet needle valve 3.5 and close the outlet needle valve 3.10;

[0074] Turn on the air booster 3.2 to deliver compressed air to the drive air interface of the air-driven booster pump 3.3, open the gas cylinder 3.1, and the air-driven booster pump 3.3 starts working, pressurizing the protective fluid and delivering it to the high-pressure chamber system 1. At the same time, the pipeline heating device 3.4 heats the protective fluid. Observe the data displayed on the paperless recorder 3.9 in real time until the temperature and pressure in the high-pressure chamber system 1 reach the target value set in the test and remain stable.

[0075] Turn on the welding machine 4.1, and the welding torch 4.3 generates an electric arc at the point to be welded. Through energy input, a molten pool is formed, and the arc spot welding operation is completed.

[0076] After spot welding is completed, turn off the welding machine 4.1. After the workpiece cools down naturally, turn off the air booster 3.2, the air-driven booster pump 3.3, and the pipeline heating device 3.4 in sequence.

[0077] Adjust the high-pressure three-way ball valve 3.11 to connect interfaces a and c, slowly open the outlet needle valve 3.10 to slowly discharge the protective fluid in the high-pressure chamber system 1 until the pressure inside the chamber drops to atmospheric pressure, and then close the gas cylinder 3.1, the inlet needle valve 3.5 and the outlet needle valve 3.10.

[0078] (iv) Post-processing stage

[0079] Open the safety lock 2.1.3 of the safety cabinet 2.1, remove the welding torch 4.3 from the welding torch holder 1.2, loosen the fixing bolts of the upper cover 1.4 of the high-pressure chamber, and take out the forming platform and the arc spot welding parts;

[0080] The molded parts can be made into standardized test specimens according to actual needs, so that mechanical properties can be measured, or after being sliced ​​and polished, microscopic observation can be carried out.

Claims

1. A metal arc spot welding test device under high temperature and high pressure environment, comprising a high-pressure chamber system (1), a safety system (2), an environmental control system (3), and an arc welding system (4), characterized in that: The high-pressure chamber system (1) is a closed pressure vessel structure, serving as the working chamber for the arc spot welding test, providing a set high-pressure environment for the spot welding process. The high-pressure chamber system (1) integrates a leveling component, an overpressure protection component, and an environmental parameter detection interface. The safety system (2) is enclosed on the outside of the high-pressure chamber system (1) and integrates a high-frequency operation component for personnel safety protection and operational convenience during the test. The environmental control system (3) is connected to the high-pressure chamber system (1) in a closed manner through a high-pressure pipeline, used to deliver protective fluid into the high-pressure chamber system (1) and to precisely regulate and monitor the ambient temperature and pressure inside the high-pressure chamber system (1) in real time to simulate the environmental parameters of extreme deep-sea or deep-earth conditions. The welding execution end of the arc welding system (4) is sealed and installed on the top of the high-pressure chamber system (1), and its grounding end is stably electrically connected to the high-pressure chamber system (1), used to complete controllable metal arc spot welding operations in the high-temperature and high-pressure environment of the high-pressure chamber system (1) and prepare standardized welding samples that meet the performance testing requirements.

2. The metal arc spot welding test device under high temperature and high pressure environment according to claim 1, characterized in that, The high-pressure chamber system (1) includes a welding torch holder fixing plate (1.1), a welding torch holder (1.2), an insulating gasket (1.3), a high-pressure chamber upper end cover (1.4), an upper ceramic insulating ring (1.5), a welding wire high-pressure sealing ring (1.6), a welding wire high-pressure sealing ring seat (1.7), a lower ceramic insulating ring (1.8), an upper high-pressure chamber sealing ring (1.9), a safety valve (1.10), a high-pressure chamber body (1.11), a lower high-pressure chamber sealing ring (1.12), a high-pressure chamber lower end cover (1.13), and anchor bolts (1.14); the high-pressure chamber body (1.11) is welded to an upper flange, a lower flange, and an intermediate cylinder, and the upper flange is connected to the high-pressure chamber via bolts. The upper end cover (1.4) of the chamber is fixedly connected, and the lower end flange is fixedly connected to the lower end cover (1.13) of the high-pressure chamber by bolts, together forming a sealed molding cavity; the mating surface of the upper end flange and the upper end cover (1.4) of the high-pressure chamber is provided with a sealing ring groove, and the upper high-pressure chamber sealing ring (1.9) is embedded in the sealing ring groove to achieve static sealing between the two; the mating surface of the lower end flange and the lower end cover (1.13) of the high-pressure chamber is provided with a sealing ring groove, and the lower high-pressure chamber sealing ring (1.12) is embedded in the sealing ring groove to achieve static sealing between the two; the outer wall of the intermediate cylinder is provided with multiple threaded interfaces for connecting functional components and the environmental control system (3).

3. The metal arc spot welding test device under high temperature and high pressure environment according to claim 2, characterized in that, The upper cover (1.4) of the high-pressure chamber has a center axis shoulder hole for passing through the welding wire and the welding execution end. The upper ceramic insulating ring (1.5) is pressed into the axis shoulder hole, the welding wire high-pressure sealing ring (1.6) is installed in the axis shoulder hole, and the welding wire high-pressure sealing ring seat (1.7) is screwed into the axis shoulder hole and presses the welding wire high-pressure sealing ring (1.6) to achieve dynamic sealing at the welding wire passage. The lower ceramic insulating ring (1.8) is nested in the welding wire high-pressure sealing ring seat (1.7). The upper ceramic insulating ring (1.5) and the lower ceramic insulating ring (1.8) together constitute the insulating protection structure between the welding execution end and the upper cover (1.4) of the high-pressure chamber.

4. The metal arc spot welding test device under high temperature and high pressure environment according to claim 2, characterized in that, The welding torch holder (1.2) is positioned and installed in the positioning groove on the upper end face of the high-pressure chamber upper cover (1.4). The welding torch holder fixing piece (1.1) is fixedly connected to the high-pressure chamber upper cover (1.4) by bolts and presses the welding torch holder (1.2) to fix the welding execution end. The insulating gasket (1.3) is placed between the contact surfaces of the welding torch holder (1.2) and the high-pressure chamber upper cover (1.4) for insulation isolation between the two. The safety valve (1.10) is threadedly installed on the side wall interface of the high-pressure chamber body (1.11) to form the overpressure protection component for overpressure relief protection of the high-pressure chamber system (1). The anchor bolt (1.14) is threadedly screwed onto the high-pressure chamber lower cover (1.13) to form the leveling component for leveling adjustment and overall fixation of the high-pressure chamber system (1).

5. The metal arc spot welding test device under high temperature and high pressure environment according to claim 1, characterized in that, The safety system (2) includes a safety cabinet (2.1) and a support (2.2); the safety cabinet (2.1) covers the outside of the high-pressure chamber system (1) and constitutes the physical protection structure for the test process; the support (2.2) is used to integrate and support the small-sized, high-frequency operating components in the high-pressure chamber system (1), the safety system (2) and the environmental control system (3); The safety cabinet (2.1) includes a top cover (2.1.1), a handle (2.1.2), a safety lock (2.1.3), a main body (2.1.4), and a base (2.1.5). The top cover (2.1.1) is hinged to the top of the main body (2.1.4) via a hinge. The handle (2.1.2) is fixed to the top surface of the top cover (2.1.1) with bolts. A through hole is provided in the center of the top cover (2.1.1). Used for threading welding execution end; the safety lock (2.1.3) is installed at the opening and closing point of the upper cover (2.1.1) and the body (2.1.4) of the safety cabinet for locking and fixing the two; the bottom of the body (2.1.4) of the safety cabinet is fixedly connected to the base (2.1.5) of the safety cabinet by bolts, and the base (2.1.5) of the safety cabinet has threaded holes for fixing the high-pressure chamber system (1); the lower end of the body (2.1.4) of the safety cabinet has a cable tray for threading high-pressure pipelines and cables.

6. The metal arc spot welding test device under high temperature and high pressure environment according to claim 1, characterized in that, The environmental control system (3) includes a gas cylinder (3.1), an air booster (3.2), a gas-driven booster pump (3.3), a pipeline heating device (3.4), an inlet needle valve (3.5), an inlet check valve (3.6), an outlet check valve (3.7), a temperature and pressure sensor (3.8), a paperless recorder (3.9), an outlet needle valve (3.10), a high-pressure three-way ball valve (3.11), and a vacuum pump (3.12).

7. The metal arc spot welding test device under high temperature and high pressure environment according to claim 6, characterized in that, The air-driven booster pump (3.3) is equipped with a protective fluid inlet, a protective fluid outlet, and a driving air interface; the protective fluid inlet is connected to the outlet of a gas cylinder (3.1) via a high-pressure pipeline, and the gas cylinder (3.1) is used to store the protective fluid required for arc spot welding; the driving air interface is connected to the outlet of an air booster (3.2) via a compressed air hose, and the air booster (3.2) is used to provide a driving air source for the air-driven booster pump (3.3); the protective fluid outlet is connected in sequence to a pipeline heating device (3.4) via a high-pressure pipeline. The inlet needle valve (3.5) and inlet check valve (3.6) are connected to the air inlet of the high-pressure chamber system (1); the air-driven booster pump (3.3) is used to pressurize the protective fluid output from the gas cylinder (3.1) to a set pressure; the pipeline heating device (3.4) is used to heat the protective fluid in the pipeline to regulate the ambient temperature inside the high-pressure chamber system (1); the inlet needle valve (3.5) is used to fine-tune the flow rate of the protective fluid; and the inlet check valve (3.6) is used to prevent the fluid in the high-pressure chamber system (1) from flowing back.

8. The metal arc spot welding test device under high temperature and high pressure environment according to claim 6, characterized in that, The outlet of the high-pressure chamber system (1) is connected to the outlet check valve (3.7) and the outlet needle valve (3.10) in sequence through pipelines, and then connected to the interface a of the high-pressure three-way ball valve (3.11); the interface b of the high-pressure three-way ball valve (3.11) is connected to the vacuum pump (3.12) through a high-pressure pipeline, and the interface c is connected to the atmosphere; the outlet check valve (3.7) is used to prevent external gas from flowing back into the high-pressure chamber system (1), the outlet needle valve (3.10) is used for fine adjustment of the exhaust flow rate, the high-pressure three-way ball valve (3.11) is used to switch the gas path on / off state, and the vacuum pump (3.12) is used to perform vacuum treatment inside the high-pressure chamber system (1) before the test to ensure the purity of the protective fluid.

9. The metal arc spot welding test device under high temperature and high pressure environment according to claim 6, characterized in that, The temperature and pressure sensor (3.8) is threaded onto the side wall interface of the high-pressure chamber system (1) to form the environmental parameter detection interface, which is used to collect temperature and pressure data inside the high-pressure chamber system (1) in real time; the paperless recorder (3.9) is electrically connected to the temperature and pressure sensor (3.8) and is used to store, display and output the collected temperature and pressure data in real time.

10. The metal arc spot welding test device under high temperature and high pressure environment according to claim 1, characterized in that, The arc welding system (4) includes a welding machine (4.1), a grounding wire / cable holder (4.2), a welding torch (4.3), and a grounding clamp (4.4); the welding torch (4.3) constitutes the welding execution end, and the grounding clamp (4.4) constitutes the grounding end; the positive terminal of the welding machine (4.1) is electrically connected to the welding torch (4.3) via a cable, and the negative terminal is electrically connected to the grounding clamp (4.4) via a grounding wire; the welding machine (4.1) is used for precise control and recording of welding voltage, welding current, and wire feeding speed during spot welding; the welding torch... (4.3) The welding torch holder (1.2) is fixedly installed on the high-pressure chamber system (1), and its welding nozzle end extends into the forming cavity of the high-pressure chamber system (1); the grounding clamp (4.4) is stably clamped on the high-pressure chamber body (1.11) of the high-pressure chamber system (1) to form a complete and safe welding current circuit; the grounding wire / cable holder (4.2) is used to fix and guide the cable and grounding wire; the arc welding system (4) also integrates an automatic weld tracking module for precise positioning of the welding position and automatic tracking of the weld trajectory during spot welding.

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