TA2 Titanium Tube: Weld Protection for 80% Early Failure 3 Pit (2026 Rev)
Published by Engineering Team, Shaanxi Qianyi Tuoda Technology Co., Ltd on 2026-07-22
The processing technology applicable to ordinary steel pipes is directly applied to TA2titanium pipeLeakage is easy to occur on TA2titanium pipe 80% of early failures occur at the weld site.The core reason is that titanium will absorb hydrogen and oxygen above 400℃, Once the weld appears blue-purple oxide, Acicular porosity or heat affected zone embrittlement, There is a high probability of leakage within half a year to two years.
TA2 titanium pipe(TA2 Titanium Tube/Pipe) is made of industrial pure titanium TA2, that is, Grade2, titanium content ≥99.3% as raw material, after hot rolling, cold rolling, annealing, pickling processing, finished outer diameter range φ6-φ720 mm.This article systematically explains TA 2titanium pipeSpecification classification, welding process, implementation standards and selection of procurement points.
TA2 titanium pipeCompared with 304, 316L stainless steel pipe and N6 nickel pipe, the density is only 4.51g/cm³, and the weight is lighter;The corrosion resistance life of wet chlorine and seawater conditions can reach more than 15 years, and the anti-biological adhesion performance is excellent.During welding operation, argon with purity no less than 99.99% shall be introduced into both sides of the weld seam;Titanium and titanium contact is easy to bite, the purchase cost is 4-7 times that of stainless steel pipe.
2024 TA2titanium pipeMarket distribution: φ6-φ89mm, wall thickness 0.5-3mm cold-rolled thin-walled tube accounted for 32%;φ89-φ219mm, wall thickness 3-10mm cold-drawn medium-wall tubes account for 41%;φ219-φ720mm, wall thickness 10-50mm hot rolled thick walled tubes accounted for 27%.Heat exchange thin-walled tubes are the largest category, accounting for 38%, followed by chemical process pipelines and power condenser tubes.
I. TA2titanium pipeThree core causes of failure
TA2 is industrialtitanium pipeThe brand with the largest amount of medium, relatively low cost, stable welding performance.However, the application scenario is wide, which also causes 80% of early failures to be concentrated in TA2 pipes, mainly at three points:
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oxidation color exceeding standard: The argon protection on the back of the weld seam is insufficient, and the weld seam is yellowish and blue-purple.Titanium begins to oxidize at 200℃, High hardness of oxide layer after 400℃, plastic deterioration, Cracking along the oxide layer during operation.
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Porosity and inclusion defectsIncomplete groove cleaning or defects in base metal, Needle porosity formed in weld, tungsten inclusion, slag inclusion, Causes seal failure.
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vibration fatigue cracking: Thin-walledtitanium pipein medium scour, Fatigue Fracture of Equipment under Vibration, Thin-walled heat exchange tubes within φ25mm, The cracking speed will be accelerated when the pipe end constraint is large.
TA2 titanium pipe 80% of the failures are concentrated in welds, and most of the weld failures are caused by inadequate weld protection.
II. TA2 titanium tube specification classification
Divided by production process, Welded pipe is formed by titanium strip welding + argon arc welding, Specifications φ6-φ720mm, Wall thickness 0.5-6mm, Mostly used in chemical low pressure pipelines, common heat exchangerSeamless pipe extrusion + cold drawing process, φ6-φ219mm, wall thickness 0.4-25mm, suitable for high temperature and high pressure pressure conditions;Thick-walled extruded cross-rolled pipe, φ114-φ720mm, wall thickness 10-50mm, used for PTA plant, offshore engineering;After cold bending and annealing treatment, U-shaped tubes are used as heat exchange tubes of tubular heat exchangers.Coil suitable for immersion cooling, continuous reaction;Titanium steel explosive clad pipe can be selected for large-diameter scenes to reduce project cost.
According to wall thickness, D/t≥20 is thin-walled tube;D/t in the range of 10-20 belongs to the middle wall chemical general pipe;D/t4-10 is high pressure thick wall pipe;D/t≤4 belongs to ultra-thick pipe, which is mostly used in marine and nuclear power projects.
Divided into heat exchange tubes by use, condenser, Chemical process pipeline, reactor insertion tube, marine pipeline, Nondestructive testing for different purposes, hydrostatic test, The technical requirements of expansion process are different.
TA2 pipe chemical composition requirements titanium matrix ≥99.3%, iron, carbon, nitrogen, oxygen, Interstitial elements such as hydrogen have strict limitsAnnealed state supply, tensile strength ≥345MPa, yield strength ≥275MPa, elongation ≥20%.
III. Key points of manufacturing process
The biggest difference between TA2 titanium pipe production and stainless steel pipe, Welding process double-sided argon protection, Heat treatment must be vacuum or argon protection, Production tools must be isolated from carbon steel.
seamless process, Vacuum Melting of Titanium Ingot, high-temperature extrusion, multipass cold rolling, Intermediate annealing and final annealing under vacuum argon protection, acid passivation, eddy current ultrasonic nondestructive testing, cutting to length, Identify the package.
welded pipe flow, Titanium strip roll forming, TIG plasma welding, Double-sided high-purity argon protection for welds, On-line eddy current testing, finishing, anneal, Pickling inspection.
Key process control: extrusion strict control of heating temperature;Cold drawing uses special lubrication;The annealing atmosphere must be protected to prevent oxidation;Acid pickling control ratio and duration;Welding argon purity ≥99.99%, low current rapid welding, groove machining;Eddy current test and hydrostatic test shall be conducted on finished products. Chlorine ion in water for hydrostatic test shall be controlled.
Iron pollution is the number one risk of TA2 titanium pipe, iron filings embedded in titanium surface will form local corrosion points, short-term leakage.Titanium material processing must be independent workshop, fixture, tools, gloves are prohibited and carbon steel mixed.
IV. Implementation of standards and engineering applications
Domestic implementation GB/T3624 seamless titanium pipe, GB/T3625 titanium heat exchanger pipe, GB/T26057 titanium welded pipe;ASTM B861, ASTM B338 and ASTM B862 are commonly used internationally. For pressure vessel projects, refer to ASME SB-338.The standards for heat exchange tubes and ordinary process pipelines cannot be mixed, and the outer diameter tolerance requirements for heat exchange tubes are more stringent.
TA2 titanium tubes are widely used in chlor-alkali applications, wet desulfurization, sea water desalination, electric condenser, pharmacy, titanium dioxide, marine equipment, nuclear power industry.Typical case: replacement of TA2 titanium tube for chlorine cooler in caustic soda plant to solve 316L short-term perforation problem;PTA oxidation reactor TA2 tube array is suitable for high temperature condition of bromine-containing acetic acid;Seawater cooling TA2U heat exchange tubes in power plants operate stably for a long time.
V. Guide to pit avoidance for type selection procurement
TA2 titanium tube selection six-step method: the first step to confirm the medium, temperature, pressure;the second step matches the titanium material grade;The third step is to determine the use of the pipe (heat exchange/condensation/process pipeline);Step 4: Determine outer diameter, wall thickness, length and tolerance;step 5, selecting product standards;Step 6: Specify acceptance levels for nondestructive testing.
The purchase contract shall specify the brand number, size specification, supply state, executive standard, inspection item, surface treatment, identification of product, Warranty period 24 months, Manufacturer supporting material certificate, Flaw detection report.
Procurement focus on six quality hazards: heat exchange tube selection error standard, tolerance exceeds the standard caused by expansion joint leakage;Oxidation of weld under argon protection on the back;Bevel cleaning is not in place to produce weld porosity;Cross contamination of carbon steel leads to iron ion corrosion;The product is not annealed, and the pipe is brittle.100% eddy current inspection omitted for critical pipes, defect missed.
Domestic TA2 titanium tube manufacturing technology is mature, Domestic manufacturers can stably supply φ6-φ720mm full-specification products, Cost performance better than importsOnly nuclear power level I pressure, high-end offshore projects import products exist premium.
Material selection idea: TA9 is selected for strong reducing acid working condition;TA2 or TA10 is selected for long-term corrosion protection of high temperature wet chlorine and seawater;TC4 is selected for high pressure bearing;Titanium steel clad pipe is adopted for cost reduction of large diameter pipeline;TA2 industrial pure titanium is selected for ordinary corrosion conditions.
VI. Industry development trend
TA2 titanium pipe industry three directions: welded pipe gradually replace small diameter seamless pipe;φ720mm large specification titanium pipe, titanium steel composite large diameter pipeline demand continues to rise;3D printing of special-shaped titanium pipe joints, on-site repair process gradually landing.
Relying on the advantages of Baoji China Titanium Valley Industrial Cluster, Shaanxi Qianyi Tuoda Technology can supply TA2 titanium seamless pipe, titanium welded pipe, U-tube, Supporting material certificate, Eddy Current Inspection Report, Chlorine alkali, sea water desalination, wet desulfurization, Electric condenser and other chemical projects.
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Data sources: GB/T 3624, GB/T 3625, ASTM B861, titanium industry engineering application cases
disclaimer, present process, Selection parameters are only for technical reference, Chemical pressure equipment TA2 titanium pipe selection procurement needs to be reviewed by professional engineers, Determine the final technical plan based on project working conditions.