The operating technique for TIG welding titanium alloy pipes

Titanium alloy pipe TIG welding when the operation practice is basically similar to stainless steel, in the case of ensuring complete weld penetration as much as possible to use a smaller welding line energy, that is, fast welding straight line transport gun and filler wire. Please pay attention to the following mainly Welding operation points:

Pre-welding through a period of time for replacement, you can use the open flame detection method to check the weld opening, confirm that the gas in the pipe is completely argon, and then weld. Adopt short arc welding, do not swing the torch and wire. Covering the surface even if you want to swing, but only a slight slow swing. The end of the wire can not be removed from the protective range during the welding process, otherwise, the end of the wire will be oxidized; if the end of the wire is found to be oxidized, the oxidized part must be cut off before use. After stopping welding, the gas should be fed with a lag until the temperature of the welding zone is reduced to below 300℃. When welding, the arc starting and closing points must be carried out in the breach shall not start and close the arc on the base material.

When sending the wire can not be a fast wire to send a pump to fill the wire, should be slow and uniform wire to the molten pool inside the send, otherwise, it will cause gas turbulence, affecting the protective effect. Welding nozzle and the mouth of the distance in the case do not affect the line of sight the lower the better, the angle of 75 ° or so, but can not tungsten electrode and the base material to touch and cause the tungsten folder; the welding wire and the mouth of the angle of 12 ° or so. In the welding process, the temperature between the layers must be strictly controlled, ten thousand a layer to wait for the temperature to drop to room temperature before continuing to weld the next layer. The rubber skin blocking plate and the inner diameter of the tube should be 0.5 ~ 1mm gap between the welding can play a pre-welding replacement of the air in the tube, the welding process to release excess argon, and the role of cooling. Welding should always observe the weld surface color, silver-white for the best, followed by gold, purple, blue, grey, and off-white.

The welding environment is very important, the welding site must be kept dry and clean, welding ambient temperature should be controlled above 18 °; The welding area without penetrating wind, welding pool, and heat-affected zone is prohibited water, water vapor, or other gases infiltration, otherwise, there must be a cover measure to avoid contamination of the weld seam to affect the quality of welding. In short, to weld titanium and its alloy pipeline, from the selection of welding consumables, open bevel grinding, cleaning and drying, environmental measures, gas protection, process parameters, welding operations and so on each link is very important, seriously, so that you can weld a qualified welded joints.