Titanium heat exchange pipe and pipe plate manual tungsten electrode argon arc welding weld joint surface protection device and use method thereof

Abstract

The invention provides a titanium heat exchange pipe and pipe plate manual tungsten electrode argon arc welding weld joint surface protection device and a use method thereof, and belongs to the fieldof pressure container manufacturing. The problem about weld joint surface protection is solved. The device comprises a support part and a gas supply part. The support part is provided with an aluminumalloy arc-shaped plate sliding way (1) and two sets of clamping parts, a welding gun is clamped by one set of clamping part, and the gas supply part is clamped by the other set of clamping part. Theuse method of the protection device includes the steps that the manual tungsten electrode argon arc welding welding gun (15) is inserted into a clamping ring (2) of the assembled protection device, and the manual tungsten electrode argon arc welding welding gun (15) and the protection device are fixed together by screwing down two hexagonal fastening screws (5); the angle and the distance betweenthe manual tungsten electrode argon arc welding welding gun (15) and a porcelain bushing nozzle (6) are adjusted, and the whole device is fixed; a ventilating hose (14) is connected to a ventilating nozzle (9) of the protection device, and protective gas is introduced; and the protection device moves along with movement of the welding gun (15) in the welding process, and the protective gas immediately covers the working area of the welding gun. The welding quality of pipe plates and heat exchange pipes of titanium heat exchangers is guaranteed.

Description

[0001] Technical field [0002] The invention belongs to the field of pressure vessel manufacturing and relates to the welding of titanium heat exchanger tube sheets and heat exchange tubes. Background technique [0003] Titanium has much better corrosion resistance than stainless steel and aluminum in many media, especially in seawater, salt water and other chlorine-containing media, and its specific gravity is light, and its specific strength is high. It is used in aerospace, pharmaceutical, chemical, and pressure vessels. and other fields have a wide range of applications. Titanium is very easy to oxidize at high temperature. When the temperature reaches 300°C, it starts to absorb oxygen, hydrogen, and nitrogen. Due to the high melting point of titanium, poor thermal conductivity, and small heat capacity, titanium welding has a long residence time at high temperature and slow cooling speed. When the heat exchanger tube plate and the heat exchange tube are welded by manua...

AI Technical Summary

Problems solved by technology

Titanium is very easy to oxidize at high temperature. When the temperature reaches 300°C, it starts to absorb oxygen, hydrogen, and nitrogen. Due to the high melting point of titanium, poor thermal conductivity, and small heat capacity, titanium welding has a long residence time at high temperature and slow cooling speed. When the heat exchanger tube plate and the heat exchange tube are welded by manual argon tungsten arc welding, the protection area is required to be larger. Only the gas that comes with the manual argon tungsten arc welding torch is used for protection. The surface of the weld will still be oxidized and bluish, and the protection effect reaches less than required

After the weld is oxidized, the hardness increases, the plasticity and toughness will drop sharply, the corrosion resistance will deteriorate, and the quality of the product will not be guaranteed.

Images