(1) welding should be selected within the acceptable range of process parameters of small heat input welding, interlayer temperature not higher than 200 ℃, high temperature to prevent too long grain growth.
(2) titanium seamless pipe welding operation should be carried out under argon protection: The torch nozzle guard the bath, drag the torch cover to protect the outer surface of the hot weld and near the weld area, filling the inner tube weld and argon protection the inner surface near the weld area, the specific measures: large diameter welded pipe, tube staff to wear a gas mask and holding a protective cover on the back to protect the weld pool; when a smaller diameter pipe welding or fixed orifice, the tube from the inner surface of the groove 150-300mm (based on operational whichever is greater) at the use of soluble paper seal, and then inserted into a mass-soluble paper to prevent the inner tube general pressure over seal damage soluble paper, and then filled with argon gas to air drain tube。 Must be fully pre-filled with argon before welding, after welding should delay argon so that the high-temperature region sufficiently cooled to prevent surface oxidation。
(3) during welding filler wire should remain under the protection of argon。 After extinguishing the wire can not be immediately exposed to the atmosphere, should be removed from the weld protection。 As the wire is contaminated, oxidation discoloration, contamination portion should be removed。
(4) shall not in the weldment surface arc or testing arc; arc welding should ensure the quality and yield of the arc; crater should be filled crater, multi-layer welding indirect head should be staggered.
(5) In addition there are special requirements, each weld should complete a continuous weld, as was interrupted for some reason, must be checked again when welding, after confirming that no crack may continue welding. (6) If the welding operations when accidentally clip tungsten, should stop welding operation, with clear tungsten grinder point, re-polish the ends of the tungsten level reached before re-welding operation after demands to begin with the same welding operation.
(7) titanium pipe welding environment if one of the following conditions occur, should stop welding without protective measures:
1) wind speed ≥2m / s
2) relative humidity greater than 90%
3) rain snow;
4) temperature than 0 ℃.
(8) weld repair process and the same original welding process. Times of repairing the same position more than twice, the second time For rework, repair measures should be developed. After approval of welding engineer responsibility, and it should be noted in construction recorded species.