The Governing Standard
Welded titanium pipe is covered by ASTM B862 and its ASME counterpart SB862, which define the requirements for welded titanium and titanium alloy pipe. The specification controls chemical composition, tensile properties, dimensions, straightness and surface quality for each grade. Pipe is ordered to B862 with the grade, size and testing class stated on the purchase document.
Manufacturing Route
Welded pipe is produced from strip that is roll-formed into a tube and welded by tungsten arc or high-frequency methods with full argon shielding. After welding, the pipe is sized, straightened and annealed, and the weld seam is flattened or worked to match the wall. The finished pipe is cut to length and end-finished by facing or beveling.
Dimensions and Tolerances
B862 defines the outside diameter range, wall thickness schedules and the tolerances for diameter, wall and straightness. Pipe is supplied in the sizes available from the mill, and the ordered dimension is verified on every length. Lengths, end finish and surface condition are confirmed at order entry and reported on the certificate.
Mechanical and Corrosion Properties
The tensile requirements of B862 match the grade, so Grade 2 welded pipe must meet 345 MPa minimum tensile strength and Grade 12 must meet 483 MPa. The corrosion resistance of the welded pipe equals the parent strip because the weld is produced under inert shielding with matching filler. The welded product carries the same grade designation as seamless material.
Testing and Inspection
Every welded pipe is dimensionally verified and pressure tested, with hydrostatic testing as the standard method. Flattening and flaring tests check the soundness of the weld, and non-destructive examination by ultrasonic or eddy current methods is applied where the order requires it. The certificate records the test results and the heat number of the material.
Applications
Chemical process piping for corrosive media.
Seawater and desalination plant lines.
Pulp and paper bleaching systems.
Marine and offshore utility piping.
Frequently Asked Questions
Q: Which standard covers titanium welded pipe?
A: ASTM B862 and ASME SB862 cover welded titanium and titanium alloy pipe.
Q: How is welded pipe manufactured?
A: Strip is roll-formed, welded under argon shielding, sized, annealed and tested.
Q: Does the weld affect corrosion resistance?
A: No, the weld is produced with inert shielding and matching filler, so the pipe keeps the corrosion performance of the parent strip.
Q: What tests apply to welded pipe?
A: Hydrostatic testing, flattening and flaring checks, and non-destructive examination where required.
Q: What is the strength of Grade 2 welded pipe?
A: A minimum tensile strength of 345 MPa under B862.
Q: Where is welded titanium pipe used?
A> In chemical, seawater, desalination, pulp and offshore piping systems.
