Self-regulating gas shield for welding titanium alloy structures

Abstract

The utility model discloses a kind of self-adjusting gas protection devices of titanium alloy structure welding, including rigid protection gas cavity, flexible sealing cover, eddy current pipe cooling module, external high-pressure protection gas source;Wherein the gas inlet of eddy current pipe cooling module is connected with external high-pressure protection gas source, and cold gas outlet is connected with the gas inlet of rigid protection gas cavity;Multiple airflow micropores are arranged on the inner side wall of rigid protection gas cavity, and flexible sealing cover is fixedly connected at the bottom of rigid protection gas cavity.The utility model is provided by rigid protection gas cavity and flexible sealing cover etc., provides a closed, full of high-purity inert gas environment for weld etc., avoids the invasion of air, and is very suitable for complex three-dimensional trajectory weld.

Description

Technical Field

[0001] This utility model relates to the field of titanium alloy welding technology, specifically to a self-regulating gas protection device for welding complex titanium alloy structures in aerospace, marine engineering and other fields. Background Technology

[0002] Titanium alloys are increasingly used in the manufacture of high-end equipment due to their high specific strength, excellent corrosion resistance, and good mechanical properties. However, titanium alloys are chemically extremely reactive and readily react with elements such as oxygen, nitrogen, and hydrogen in the air at high welding temperatures. This reaction leads to the formation of a brittle layer in the weld zone, severely deteriorating the joint's plasticity, toughness, and fatigue performance. Therefore, protecting the molten pool and areas with temperatures exceeding 400°C during welding is crucial to ensuring the quality of titanium alloy welds.

[0003] Currently, conventional methods for protecting titanium alloy welds primarily employ handheld or custom-made rigid shields combined with back argon purging. However, these methods have the following limitations: (1) For complex three-dimensional welds such as curved surfaces and folded edges, traditional drag covers are difficult to fit well, resulting in dead zones and poor protection, which can easily lead to oxidation. (2) During long-term welding, the shroud itself is heated to a high temperature, which may not only burn the workpiece, but also become a heat radiation source, prolonging the high temperature dwell time of the weld, which in turn aggravates grain growth and performance degradation. (3) Back-side argon filling is difficult to implement for closed cavity structures, and is costly and inefficient; (4) The flow rate of the traditional shielding gas is preset before welding and cannot be adjusted according to the temperature changes of the weld and heat-affected zone. The utilization rate of the shielding gas is sometimes high and sometimes low, resulting in some waste.

[0004] Therefore, there is an urgent need to develop a gas protection device that can be applied to different workpiece shapes, provide stable and long-lasting performance, and actively control the temperature of the protected area. Utility Model Content

[0005] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a self-regulating gas protection device for welding titanium alloy structures.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A self-regulating gas protection device for welding titanium alloy structures, characterized in that it includes a rigid protective gas chamber, a flexible sealing cover, a vortex tube cooling module, and an external high-pressure protective gas source; wherein the gas inlet of the vortex tube cooling module is connected to the external high-pressure protective gas source, and the cold gas outlet of the vortex tube cooling module is connected to the air inlet of the rigid protective gas chamber; the rigid protective gas chamber is a hollow cavity and multiple airflow micro-holes are opened on the inner wall of the rigid protective gas chamber, and the flexible sealing cover is fixedly connected to the bottom of the rigid protective gas chamber.

[0007] Furthermore, an infrared temperature monitoring module (using a YFL-MITC split-type infrared thermometer) is fixedly connected to the rigid protective gas cavity, and the probe of the infrared temperature monitoring module penetrates the rigid protective gas cavity from top to bottom and reaches the weld seam; the infrared temperature monitoring module is electrically connected to the PLC controller, and the PLC controller is electrically connected to the eddy current cooling module.

[0008] Compared with the prior art, the beneficial effects of this utility model are as follows: This invention provides a closed environment filled with high-purity inert gas for welds by using a rigid protective gas chamber and a flexible sealing cover, preventing air intrusion. It is very suitable for complex three-dimensional trajectory welds. This invention, through the use of eddy current tube cooling modules and other features, can effectively remove the heat accumulated in the welding area, inhibit the coarsening of the weld and base material grains, and prevent the invention itself from overheating, thus achieving the dual effects of protection and cooling. This utility model achieves real-time temperature feedback through infrared temperature monitoring modules and other features, and can dynamically adjust cooling intensity and gas flow rate, thus realizing effective control of the protection process. This invention reduces the number of interruptions caused by overheating of the welding shield, allows for longer continuous welding time, improves welding efficiency, and significantly enhances the stability and reliability of weld quality. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the control principle of this utility model; Among them, 1. Rigid protective gas chamber; 2. Flexible sealing cover; 3. Vortex tube cooling module; 4. Infrared temperature monitoring module; 5. PLC controller; 6. Flow regulating valve; 7. Welding torch clamping mechanism; 8. Welding torch; 9. Workpiece; 11. Airflow micropore; 31. Protective gas pipeline; 91. Weld seam. Detailed Implementation

[0010] The present invention will now be further described with reference to the accompanying drawings. The following are the most preferred embodiments of the present invention, but they do not limit the scope of protection of the present invention. Any equivalent or similar substitutions without departing from the concept of the present invention shall fall within the scope of protection of the present invention.

[0011] like Figure 1 , 2As shown, the self-regulating gas protection device for welding titanium alloy structure of this utility model includes a rigid protective gas chamber 1, a flexible sealing cover 2, a vortex tube cooling module 3, and an external high-pressure protective gas source. The gas inlet of the vortex tube cooling module 3 is connected to the external high-pressure protective gas source through a protective gas pipeline 31, and a flow regulating valve 6 is fixedly connected to the protective gas pipeline 31. The cold gas outlet of the vortex tube cooling module 3 (with an 8mm quick-connect inlet and an 8mm cold gas outlet) is connected to the inlet of the rigid protective gas chamber 1. The rigid protective gas chamber 1 is a hollow cavity, and its inlet is connected to the cavity of the rigid protective gas chamber 1. Multiple airflow micro-holes 11 communicating with the cavity of the rigid protective gas chamber 1 are opened on the inner wall of the rigid protective gas chamber 1. The flexible sealing cover 2 is fixedly connected to the bottom of the rigid protective gas chamber 1.

[0012] This invention also uses a conventional welding torch clamping mechanism 7 to fix the torch head of the welding torch 8, which moves synchronously with the welding torch. An infrared temperature monitoring module 4 is fixedly connected to the upper surface of the rigid protective gas chamber 1, with its probe penetrating the rigid protective gas chamber 1 and pointing towards the weld 91. A flexible sealing cover 2 is fitted onto the surface of the titanium alloy workpiece 9, forming a relatively sealed protective space. Low-temperature protective gas (such as argon) flows uniformly from the airflow micro-holes 11 at the bottom of the rigid protective gas chamber 1, filling the sealed space covered by the flexible sealing cover 2, providing sufficient and long-lasting protection for the weld 91 that has just undergone high welding temperatures and the heat-affected zone that is still at a high temperature.

[0013] The rigid protective air chamber 1 of this invention is preferably made of copper, a material with excellent thermal conductivity, to ensure uniform airflow distribution and pre-cooling through heat exchange with the chamber wall. Several micro-holes 11 with a diameter of 0.5-1.0 mm (preferably 0.8 mm) are machined at its bottom. A flexible sealing cover 2 is fixedly connected to the bottom outer wall of the rigid protective air chamber 1 and is made of high-temperature resistant silicone material (e.g., capable of long-term operation above 250°C). This design allows the flexible sealing cover 2 to have good flexibility to adapt to the unevenness of the workpiece surface while maintaining a preset shape within a certain temperature range, providing a durable and stable sealing force.

[0014] Infrared temperature monitoring module 4 acts as the system's "eyes," acquiring temperature signals from the weld area in real time. PLC controller 5 acts as the "brain," receiving the temperature signals and comparing and calculating them with internally preset thresholds (e.g., T1=250℃, T2=100℃). Then, it sends control commands to the actuator—flow regulating valve 6 (this flow regulating valve 6 is installed at the gas supply end of protective gas pipeline 31, after the argon gas pressure reducer, as shown in the control principle diagram, and is controlled by the PLC). For example, when the detected temperature exceeds 250℃, PLC controller 5 instructs flow regulating valve 6 to increase the protective gas flow rate, and vortex tube cooling module 3 subsequently increases the proportion of cold gas output, thereby enhancing the cooling effect; when the temperature drops below 100℃, indicating that the area is sufficiently safe, the system automatically restores to the basic protective flow rate to conserve gas consumption. The entire process requires no manual intervention, achieving intelligent and precise control.

[0015] Implementation Case: Welding a complex curved TC4 titanium alloy component. The device is mounted on the welding torch, and its position is adjusted so that the flexible sealing cover 2 is pre-fitted to the surface of the workpiece 9. The gas source of the eddy current tube cooling module 3 is turned on, and the base cooling gas temperature is set to 10℃. The PLC controller 5 is initialized, and the control thresholds T1=250℃ and T2=100℃ are set. Welding is started with the welding torch 8, and the device moves synchronously with it. Throughout the welding process, the high-temperature zone behind the weld is always enveloped in a sealed environment filled with low-temperature argon gas. The infrared temperature monitoring module 4 provides real-time temperature feedback, and the PLC controller 5 dynamically adjusts the cooling intensity. Post-weld inspection shows that the entire weld and heat-affected zone are uniformly bright silver-white, without any oxidation. Testing shows that the tensile strength of the joint reaches over 98% of the base material, the bending pass rate is 100%, and the fatigue performance is significantly better than joints welded using traditional protection methods.

[0016] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A self-regulating gas protection device for welding titanium alloy structures, characterized in that, It includes a rigid protective air chamber, a flexible sealing cover, a vortex tube cooling module, and an external high-pressure protective air source; wherein the gas inlet of the vortex tube cooling module is connected to the external high-pressure protective air source, and the cold air outlet of the vortex tube cooling module is connected to the air inlet of the rigid protective air chamber; the rigid protective air chamber is a hollow cavity and has multiple airflow micro-holes on its inner sidewall; the flexible sealing cover is fixedly connected to the bottom of the rigid protective air chamber.

2. The self-regulating gas protection device for welding titanium alloy structures according to claim 1, characterized in that, An infrared temperature monitoring module is also fixedly connected to the rigid protective air cavity, and the probe of the infrared temperature monitoring module penetrates the rigid protective air cavity from top to bottom; the infrared temperature monitoring module is electrically connected to the PLC controller, and the PLC controller is electrically connected to the eddy current cooling module.

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