ASTM A209 Grade T1a Seamless Boiler Tubes
ASTM A209 Grade T1a Steel Tubes covers several grades of minimum-wall-thickness, seamless, carbon-molybdenum alloy-steel,boiler and superheater tubes.

Description

ASTM A209 Grade T1a Seamless Boiler Tubes 
ASTM A209 Grade T1a Seamless Alloy-Steel Boiler and Superheater Tubes
Standard:ASTM A209/A209M
Standard Specification for
Seamless Carbon-Molybdenum Alloy-Steel Boiler and Superheater Tubes
ASTM A209 Grade T1a Steel Tubes  covers several grades of minimum-wall-thickness, seamless, carbon-molybdenum alloy-steel,boiler and superheater tubes.
ASTM A209 Grade T1a Seamless BoilerTubes covers tubes 1 ⁄ 2 to 5 in. [12.7 to 127mm] inclusive, in outside diameter and 0.035 to 0.500 in. [0.9 to 12.7 mm], inclusive, in minimum wall thickness.
Materials and Manufacture
Steelmaking Practice—The steel shall be killed.
ASTM A209 Grade T1a BoilerTubes  are made by the seamless process and shall be either hot-finished or cold-finished, as specified.
HeatTreatment
Hot-finished ASTM A209 Grade T1a Seamless BoilerTubes  shall be heat treated at a temperature of 1200 °F [650 °C] or higher.
Cold-finished tubes, after the final cold finishing, be heat treated at a temperature of 1200 °F [650 °C] or higher, or tubing may be furnished in the full-annealed, isothermal annealed, or normalized and tempered condition.
If furnished in the normalized and tempered condition, the minimum tempering temperature shall be 1200 °F [650 °C]
Chemical Composition
Element Composition, % Grade T1a
Carbon 0.15–0.25
Manganese 0.30–0.80
Phosphorus, max 0.025
Sulfur, max 0.025
Silicon 0.10–0.50
Molybdenum 0.44–0.65
Mechanical Properties
 Mechanical Properties Grade T1
Tensile strength, min, ksi [MPa] 53 [365]
Yield strength, min, ksi [MPa] 28 [195]
Elongation in 2 in. or 50 mm, min, % 30
Brinell Hardness Number (Tubes 0.200 in. [5.1 mm] and over in Wall Thickness), HBW 153
Rockwell Hardness Number (Tubes less than 0.200 in. [5.1 mm] in Wall Thickness), HRB 81
Forming Operations
Tubes when inserted in the boiler shall stand expanding and beading without showing cracks or flaws.
Package
Bundles (hexagonal),Wooden Boxes,Crates (steel/wooden)
Tests
Tension Test—One tension test shall be made on a specimen for lots of not more than 50 tubes. Tension tests shall be made on specimens from two tubes for lots of more than 50 tubes
Flattening Test—One flattening test shall be made on specimens from each end ofone finished tube,
Flaring Test—One flaring test shall be made on specimens from each end ofone finished tube

Hardness Test—Brinell or Rockwell hardness tests shall be made on specimens from two tubes from each lot