Method for carrying out simulated training of non-melt argon tungsten-arc welding on liquefied natural gas (LNG) carrier for welders

Abstract

The invention relates to a method for carrying out a simulated training of non-melt argon tungsten-arc welding on a liquefied natural gas (LNG) carrier for welders, which needs to simulate the welding between film materials on a cargo tank containment system on the LNG carrier. The method comprises the following steps: firstly, clamping the welded seam of a specimen needing to be welded by using a clamping tool, and then, carrying out fixed-position welding; then, lining and pressing a radiating component at the edge of the welded seam, and clamping the radiating component by using the clamping tool; and finally, enabling the nozzle of a welding torch to be close to the edge of the radiating component for welding, and removing the clamping tool after welding. The method of the invention performs important functions of avoiding the weld penetration of invar film materials by welders in operation and controlling the post welding distortion, and greatly improves the training efficiency and effect of manual TIG welding.

Description

technical field [0001] The invention relates to LNG ship manufacturing, in particular to a method for simulated training of non-melting tungsten argon arc welding welders on the LNG ship before actual operation. Background technique [0002] With the rapid growth of my country's economy, the country's demand for energy is also increasing. As an ideal green fuel, liquefied natural gas (LNG) is mainly used in thermal power generation, city gas, and steel industry. Because of its cleanness, high efficiency and low cost, it has become the key target of development and utilization in my country at the beginning of this century. LNG carrier is the main means of transportation of LNG, and one of the main cargo tank types is GTNO.96E-2 membrane type, which needs to be able to guarantee the ability to transport natural gas at -163°C. The liquid cargo tank containment system of LNG ship is a large container on the LNG ship to accommodate liquefied natural gas, and its manufacture is ...

AI Technical Summary

Problems solved by technology

Although the flame retardant layer is placed on the back of the weld, it only plays a certain role in heat insulation. The molten droplets that have been welded will cause the wooden insulating box underneath to be scorched, and even the wooden box will be ignited if it is serious.

[0005] 2. Poor penetration of welded joints or welding defects such as weld penetration will result in poor tightness of welds, resulting in leakage of liquid cargo tanks

[0006] 3. Welders perform all-position welding with bare hands, resulting in poor straightness of the weld seam or unsightly weld seam shape

[0007] 4. The film material is heated and cooled unevenly by the welding arc, resulting in obvious deformation after welding

[0008] There are two main reasons for the above problems: one is that the invar material to be welded is thin; the other is that the welder's operation gestures are unstable, and it is difficult to control the temperature of the molten pool during welding

[0009] From the above reasons, the thickness of the material is fixed, mainly how to overcome the welding quality problem caused by the welder's unsteady manual operation

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