ASTM B338 Scope
The standard covers 22 grades of titanium and titanium alloy tubing. Below are the most commercially relevant grades, with a focus on Grade 1 (Gr.1) – the softest and most ductile unalloyed titanium grade.
| Grade | Type | Key Characteristics |
|---|---|---|
| Grade 1 (Gr.1) | Unalloyed Titanium | Highest ductility, excellent cold formability, superior corrosion resistance. Ideal for deep drawing and chemical processing. |
| Grade 2 (Gr.2) | Unalloyed Titanium | Higher strength than Gr.1, good corrosion resistance. Most widely used grade. |
| Grade 3 (Gr.3) | Unalloyed Titanium | Higher strength than Gr.2, moderate formability. |
| Grade 7 | Unalloyed Ti + 0.12-0.25% Pd | Exceptional corrosion resistance in reducing acids. |
| Grade 9 | Ti (3% Al, 2.5% V) | High strength, good weldability. |
gr1 titanium pipe (ASTM B338) is equivalent to ASTM B861 (seamless pipe) and ASTM B862 (welded pipe) for gr1 titanium tube.
Medical grade 1 titanium is covered under ASTM F67 grade 1, which has stricter purity requirements.
Available Sizes, Types & Dimensions for gr1 titanium tube
We supply gr1 titanium tube and gr1 titanium pipe in the following ranges:
| Parameter | Range / Options |
|---|---|
| Outer Diameter | 6mm to 610mm |
| Wall Thickness | 1mm to 50mm |
| Length | Single random, double random, or max 12000mm |
| Schedule | 10s, 20, 40, 40s, 60, 80, 80s, 100, 120, 140, 160, XXS |
| Type | Seamless / ERW (Welded) / Fabricated |
| Shape | Round, Square, Rectangular |
Chemical Composition
| Element | Gr.1 (gr1 titanium alloy) Max | Gr.2 Max | Gr.3 Max | Gr.7 Max | Gr.9 |
|---|---|---|---|---|---|
| Nitrogen | 0.03 | 0.03 | 0.05 | 0.03 | 0.03 |
| Carbon | 0.08 | 0.08 | 0.08 | 0.08 | 0.08 |
| Hydrogen | 0.015 | 0.015 | 0.015 | 0.015 | 0.015 |
| Iron | 0.20 | 0.30 | 0.30 | 0.30 | 0.25 |
| Oxygen | 0.18 | 0.25 | 0.35 | 0.25 | 0.15 |
| Aluminum | – | – | – | – | 2.5-3.5 |
| Vanadium | – | – | – | – | 2.0-3.0 |
| Palladium | – | – | – | 0.12-0.25 | – |
| Titanium | Balance | Balance | Balance | Balance | Balance |
Mechanical Properties
| Grade | Tensile Strength (min) | Yield Strength (0.2% offset) | Elongation (min) |
|---|---|---|---|
| Gr.1 | 35 ksi (240 MPa) | 25 ksi (170 MPa) | 24% |
| Gr.2 | 50 ksi (345 MPa) | 40 ksi (275 MPa) | 20% |
| Gr.3 | 65 ksi (450 MPa) | 55 ksi (380 MPa) | 18% |
| Gr.7 | 50 ksi (345 MPa) | 40 ksi (275 MPa) | 20% |
| Gr.9 | 125 ksi (860 MPa) | 105 ksi (725 MPa) | 10% |
Required Mechanical Tests for gr1 titanium pipe
All gr1 titanium tube products must pass the following tests without cracking or visible rupture:
Flattening Test: Tube is flattened at room temperature until the distance between platens is not more than H (calculated per ASTM B338).
Flaring Test: For tube OD ≤ 88mm and wall thickness ≤ 3.4mm, a 60° tool flares the tube end per table 4 of the standard.
Hydrostatic or Nondestructive Testing (NDT):
Welded tubing: Requires both electromagnetic (ECT) and ultrasonic (UT) tests.
Seamless tubing: Requires ultrasonic (UT) test.
All tubing: Requires hydrostatic or pneumatic test as specified.
Marking & Certification
Marking: Each tube ≥ 1/2 in. (13mm) OD is legibly marked (stenciled, stamped, or rolled) with: manufacturer's mark, ASTM designation, class, grade number (e.g., Gr.1) , and heat number. Smaller tubes in bundles have a metal tag with the same info.
Certification: Mill test certificates issued according to EN10204.3. All tubes supplied as per applicable ASTM B338 specification.
Inspection Module
All gr1 titanium pipe and gr1 titanium tube shipments undergo rigorous inspection:
Dimensional inspection: OD, wall thickness, length checked against order requirements.
Visual inspection: Surface defects (scratches, pits, cracks) examined under proper lighting.
NDT (Nondestructive Testing): 100% ultrasonic testing (UT) for seamless tubes; both UT and eddy current (ECT) for welded tubes.
Mechanical testing: Tensile, flattening, and flaring tests performed on representative samples.
Chemical analysis: Verified by an accredited third-party lab (OES or inert gas fusion per ASTM E1409, E1447).
Hardness testing: Optional but recommended for grade 1 titanium hardness verification (typically ≤ 120 HV).
Hydrostatic test: Each tube pressured to specified value, held for minimum time, checked for leaks.
Third-party inspection: Available upon request (e.g., SGS, BV, etc.).
Packaging
To ensure gr1 titanium tube arrives in perfect condition, we use the following packaging methods:
Individual protection: Each gr1 titanium pipe is wrapped in plastic film or VCI paper to prevent moisture and scratches.
Bundling: Tubes are bundled with steel straps, with protective cardboard or rubber between straps and tubes.
Wooden cases: Plywood wooden boxes (export standard) or steel-framed cases for sea freight.
Desiccant bags: Included inside sealed plastic wrapping for sea-worthily delivery.
Labeling: Each bundle/box has a weatherproof label with PO number, grade, size, quantity, and heat number.
Factory Equipment Module
| Equipment Category | Specific Machines / Capabilities |
|---|---|
| Melting & Forging | Vacuum Arc Remelting (VAR) furnace, Plasma Arc Melting (PAM) furnace, hydraulic forging press (2000 ton) |
| Tube/Pipe Mills | Cold pilger mill (seamless tube production), continuous tube reducing mill |
| Welding | Tungsten Inert Gas (TIG) welding line for longitudinal seam welded tube, laser welding for precision gr1 titanium tube |
| Heat Treatment | Vacuum annealing furnace (for stress relieving and recrystallization), hydrogen annealing furnace |
| Forming & Bending | CNC tube bender (for gr1 titanium forming/bending), hydraulic deep drawing press |
| Machining | CNC lathes, tube end facing and chamfering machines, centerless grinders (for gr1 titanium machinability) |
| Testing & Inspection | Ultrasonic flaw detector (UT), eddy current tester (ECT), hydrostatic pressure tester, universal tensile testing machine, optical emission spectrometer (OES) |
| Packaging Line | Automatic tube bundling and strapping line, shrink-wrap machine |
