ASTM B338-Seamless and Welded Titanium and Titanium Alloy Tubes

Standard Specification for Seamless and Welded Titanium and Titanium Alloy Tubes for Condensers and Heat Exchangers

Scope:

This specification covers the requirements for seamless and welded titanium tubes intended for use in:

Heat exchangers

Surface condensers

Evaporators

Seawater and chemical processing equipment

Tubes are usually supplied in the annealed condition, unless otherwise specified.

Applicable Grades (UNS Designations)

ASTM B338 includes both commercially pure (CP) titanium and titanium alloys:

Dimensional & Manufacturing Requirements

Tube Types: Seamless or Welded (typically TIG/GTAW)

Manufacturing method:

Seamless tubes: extrusion, piercing, and drawing

Welded tubes: formed from strip and welded, then cold worked and annealed

Condition: Supplied in annealed or stress-relieved condition

Tolerances: As per ASTM B338 or specified by purchaser

Hydrostatic or NDT Testing required on all tubes

Mechanical Property Requirements (as per Grade & Size)

Each grade must meet minimum tensile properties in the annealed condition. Examples:

Specific mechanical values depend on grade and wall thickness.

Testing & Quality Requirements

Chemical Composition: Must conform to respective ASTM standards for each grade (e.g., B348)

Tensile Test: One per lot or as agreed

Flattening Test (for certain sizes)

Flaring Test (for certain applications)

Hydrostatic or Air Underwater Pressure Test

Ultrasonic/Eddy Current Test: Required for welded tubes

Visual and Dimensional Inspection

Marking & Certification

Each tube must be legibly marked with:

Manufacturer’s name or logo

ASTM B338

Grade

Condition (annealed, etc.)

Heat/lot number

Material Test Reports (MTRs) must accompany each shipment, showing full chemical, mechanical, and test data.

The following is a detailed description of thedimensional requirements and tolerances for titanium and titanium alloy tubing in the ASTM B338 standardfor seamless and welded tubing (annealed condition):

Outside Diameter Range

The ASTM B338 standard applies to the following range of titanium tube sizes:

Outside Diameter Tolerances

Wall Thickness Tolerances

Length Tolerances

The following lengths are available on request:

Specified Length: ±3.2 mm (±1/8 inch)

Multiple Random Lengths: ±6.4 mm (±1/4 inch)

Random Lengths: usually 1.5-6 metres. 1.5-6 metres, range by mutual agreement

Ovality

For tubes not straightened after cold working, the maximum ovality shall not exceed two times the tolerance of the outside diameter and shall be within the limits permitted by the standard wall thickness.

Straightness

It is generally not strictly specified, but should meet customer requirements.

If required, the common straightness tolerance is 1.5 mm/1000 mm.

Notes

Tighter tolerances (e.g., aerospace or nuclear grade tubing) are available upon request or project requirements.

When used in conjunction with ASME SB-338, the tolerances are the same.