The welding process of titanium pipeline is manual tungsten inert gas arc welding (GTAW) in the atmosphere. Before welding, the titanium pipe groove and its internal and external surfaces within 25mm on both sides shall be cleaned of oil stain, and then the oxide film, burrs and surface defects shall be removed by mechanical methods such as austenitic stainless steel wire brush and reamer. Cleaning tools shall be special and kept clean; After mechanical cleaning, the groove surface and filler wire shall be degreased with sulfur free acetone or ethanol before welding. During the welding process, special protective measures shall be taken to make the parts where the temperature of titanium pipe welding area may exceed 400 ℃ partially or completely under the effective protection of argon, so as to achieve the purpose of titanium pipe welding.
Construction preparation → material acceptance → marking inspection → blanking and groove processing → groove peripheral treatment → weldment assembly → welding → weld appearance inspection → weld PT and RT flaw detection → hydrostatic test of prefabricated pipe section → drainage and drying → closed transportation of pipe orifice → on-site assembly.