ASTM A213 T22 Tubes: Material and Inspection Checks

T22 is a chromium-molybdenum grade in ASTM A213 for seamless boiler, superheater and heat-exchanger tubing.

Identify T22 within the tube specification

It should be ordered with the applicable specification, edition, dimensions and required condition. The designation alone is not an allowable pressure-temperature rating. T22 tube and similarly named P22 pipe are associated with different product specifications and should not be treated as interchangeable finished items.

Match the actual thermal and chemical environment

Selection requires the approved equipment design, metal temperatures, pressure, thermal cycling and internal and external media. Chromium-molybdenum chemistry does not establish immunity to every high-temperature corrosion or hydrogen-related mechanism. Evaluate the relevant degradation risks and design allowables with the responsible engineering organization. A general statement that T22 is widely used cannot substitute for that service-specific assessment.

Control delivery condition and fabrication

Confirm the treatment and final-condition requirements under the selected product documents. Manufacturing route, forming and subsequent joining need to be compatible with those requirements. Do not specify cold drawing as the only possible route merely because the application needs seamless tube. Review bends, tube-sheet joints, supports and any later heat treatment as parts of the complete equipment process.

Specify grade-specific acceptance evidence

List the required material identification, chemical and mechanical results, dimensions and examination records. Any additional tests or inspection witnessing should be agreed before manufacturing. Maintain heat and lot identity through cutting and fabrication. If a different alloy or condition is proposed, review its effects on equipment design, fabrication qualification and inspection rather than approving it from a generic strength comparison.

A practical specification review

A replacement heat-exchanger tube should be compared with the approved material and fabrication requirements, not chosen from a generic list of high-temperature alloys. Confirm grade, condition, dimensions and joint requirements, then review any proposed deviation with the equipment owner. The material that is easiest to source may not be the material the existing equipment is qualified to use.

Information to confirm before accepting an offer

• Identify the component or supply item, its intended function and the controlled drawing or procedure revision.
• State applicable product and project documents, material or test requirements, dimensions and the condition in which acceptance is assessed.
• Define the required evidence, inspection responsibilities, identification, reporting format and handling of deviations.
• Confirm what the quotation includes, any subcontracted operations, preservation requirements and how proposed changes will be approved.

Resolve unclear requirements before manufacture or examination. Keep the accepted offer, approved deviations and release records together so that a repeat order can use the same technical basis.

Related technical guides

• ASTM A213 T11 Tubes: Service Conditions and Ordering Requirements
• Steel Tubes for Heat Exchangers: Material and Inspection Requirements
• Seamless Boiler Tube Selection: Service, Standards and Inspection

Reference

ASTM A213 tube specification. Use the edition and requirements applicable to the actual order; this guide does not reproduce or replace the governing documents.

For a tube inquiry, send the drawing, required material and acceptance requirements through the Tenjan contact page so the requested scope and any supply limitations can be reviewed.