Titanium pipeline welding process is in the atmosphere using manual tungsten inert gas shielded welding (GTAW) welding method. Welding before the titanium tube groove and its sides on both sides of the inner and outer surface of 25mm to remove oil, the application of austenitic stainless steel wire brush, reamer and other mechanical methods to remove its oxide film, burrs and surface defects. The cleaning tool should be dedicated and kept clean; the surface of the groove after mechanical cleaning and the filling of the welding wire should be degreased before welding with acetone or ethanol without sulfur. Welding process, the use of special protective measures, so that the titanium tube welding area temperature may exceed 400 ℃ part of the local or all in the effective protection of argon to achieve the purpose of titanium tube welding.

 

Construction Inspection → Material Acceptance → Crossing Inspection → Cutting and Groove Processing → Groove Peripheral Treatment → Weldment Group → Welding → Weld Inspection → Weld PT, RT Inspection → Prefabricated Pipe Seal Hydraulic Test → Drainage, Drying → Pipe closure transport → on-site assembly.

 

How to deal with the surface of titanium tube

 

Titanium tube surface alloying can also be called a kind of coating, it is coated with titanium oxide coating on the oxide, compared with a strong bonding, wear resistance, corrosion resistance and so on. Compared with titanium palladium alloy, palladium surface content is high, saving precious metal palladium, reducing costs, but also with excellent performance

 

Titanium tube surface aluminizing can reduce the tendency of hydrogen absorption of titanium, 88% of alumina, 4% aluminum fluoride and 8% aluminum powder mixed in the titanium workpiece is the best aluminizing conditions, the temperature of 810 ℃ The The thickness and structure of the aluminized layer depend on the holding time. The use of encapsulated infiltration of aluminum, short-term diffusion can be about 2 mm thick thin coating, good adhesion, does not affect the mechanical properties of the matrix. The coating consists essentially of a titanium oxide phase, forming a barrier that is very effective in preventing hydrogen permeation.

 

Titanium tube on the palladium, can be heated by different methods can make the layer of titanium plating layer to the surface of the titanium tube diffusion, the formation of the surface of the titanium palladium alloy layer, which can improve the corrosion resistance. Heating or laser surface remelting, in principle, are feasible. The use of a laser irradiates the titanium surface to rapidly melt and coagulate, allowing the vacuum deposit of 150 microns of palladium film to be rapidly melted to form an active palladium alloy.

 

Titanium tube strength is close to the strength of ordinary steel, some high-strength titanium alloy than the strength of many alloy structural steel. At present the aircraft engine components, skeleton, skin, fasteners and landing gear and so on are using titanium alloy. The following Xiaobian to introduce the performance of titanium tube.

 

The use of temperature than aluminum alloy several hundred degrees, at moderate temperatures can still maintain the required strength. Titanium alloy in the humid atmosphere and sea water medium work, its corrosion resistance is much better than stainless steel; pitting corrosion, acid corrosion, stress corrosion resistance is particularly strong; alkali, chloride, chlorine organic products, nitric acid, sulfuric acid And so have excellent corrosion resistance. But titanium has a reducing oxygen and chromium salt medium corrosion resistance is poor. Titanium alloy at low temperature and ultra-low temperature, can still maintain its mechanical properties. Should not make slender rods and thin-walled parts, cutting the surface of the processing of a large amount of rebound.