Precautions For Repair Welding Of Titanium Pipes And Titanium Alloy Pipes

Generally, titanium pipe manufacturers cannot have flowing air in the repair welding of titanium pipes. Other aspects are the same as repair welding in the welding box. But pay special attention to:

(1) The repair welding area should not be too large, the nitrogen flow during repair welding should be larger, and the gas cannot be stopped in the middle;

(2) After the repair welding is completed, nitrogen protection should be continued until the area is cooled;

(3) For some special castings, such as complex thin-walled castings, in order to prevent oxidation of the back surface of the repair welding area, argon gas can be blown on the back surface until the casting is cooled;

(4) Repair welding operators are required to have a higher technical level.

In order to obtain titanium pipe castings with good repair welding quality, the following points should be noted in the repair welding process:

(1) The surface of the castings for repair welding must be cleaned and dried. The castings are not allowed to be directly touched before being put into the welding box.

(2) Strictly prevent short circuit between the tungsten electrode and the repair welding parts during the repair welding of the titanium pipe, which will cause the tungsten electrode to break and cause tungsten inclusions in the welding point.

(3) When the area and depth of the repair welding area are relatively large, it should be divided into multiple remote layers, and the next layer can be welded after the previous layer is completely cooled. It is absolutely not allowed to weld in one time. To prevent deformation of the casting.

(4) At the end of repair welding, the current should be gradually reduced to reduce the melting zone. Therefore, it is recommended to use pulse current to prevent sharp arc interruption and cracks.

(5) After repair welding, the casting should be allowed to cool in the box for a period of time before removing the casting to prevent cracks or deformation in the welding area of the casting caused by rapid cooling; the length of cooling time depends on the wall thickness of the casting, usually 15-30mm .

(6) After repair welding, titanium pipe castings should be annealed or hot isostatically pressed in time, and should not be left for too long, usually no more than 5 days.

(7) The number of repair welding shall not exceed the provisions of the relevant technical documents.