A213 T11 / 13CrMo4-5 Seamless Tube, Low Alloy Ferritic Steel Tube For Power Plant Boiler

A213 T11 Alloy Steel Seamless Tube – Introduction

ASTM A213 T11 is a seamless ferritic alloy steel tube designed for high-temperature service in boilers, superheaters, and heat exchangers. It offers excellent thermal strength, oxidation resistance, and creep resistance, making it ideal for pressure-bearing applications in power plants and petrochemical industries. The alloy primarily contains chromium (1–1.5%) and molybdenum (0.44–0.65%), enhancing its performance at elevated temperatures. Supplied in a normalized and tempered condition, A213 T11 tubing meets strict mechanical and chemical requirements for long-term reliability in demanding environments.

Material Overview

• Standard: ASTM A213
• Grade: T11
• Type: Seamless ferritic alloy-steel tube
• Main Alloying Elements: Chromium (1.0–1.5%), Molybdenum (0.44–0.65%)

A213 T11 Equivalent Grades

Chemical Composition (Typical Range)

Processing Steps

1. Tube Manufacturing

• Method: Seamless

• Processed by hot-extrusion or piercing of a solid billet followed by elongation through a mandrel mill.

• Cold-drawn finishing may be used for dimensional precision.

2. Heat Treatment

According to ASTM A213 specification, T11 tubes must be heat-treated as follows:

• Normalized at 850–900°C (1562–1652°F)
  (Refines grain structure and improves toughness)

• Tempered at a temperature not less than 650°C (1202°F)
  (Relieves internal stresses and restores ductility after normalizing)

Note: Heat treatment must be applied after cold finishing if it's done.

3. Cold Finishing (Optional)

• For tubes requiring tighter dimensional tolerances or smoother finishes.

• May involve:

  • Cold drawing

  • Straightening

  • Sizing

4. Descaling / Surface Treatment

• Descaled via mechanical (shot blasting) or chemical (pickling) methods if required.

5. Testing & Inspection

All tubes undergo mechanical and nondestructive testing per ASTM A213:

• Hardness test

• Flattening test

• Flaring test

• Hydrostatic or nondestructive electric test

• Dimensional check (OD, wall thickness, length)