The tubes are made by the seamless process and shall be either hot-finished or cold-finished, as specified.
Hot-finished tubes 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]
Composition, % Grade T1
Tensile strength, min, ksi [MPa]
Yield strength, min, ksi [MPa]
Elongation in 2 in. or 50 mm, min, %
Brinell Hardness Number (Tubes 0.200 in. [5.1 mm] and over in Wall Thickness), HBW
Rockwell Hardness Number (Tubes less than 0.200 in. [5.1 mm] in Wall Thickness), HRB
Tubes when inserted in the boiler shall stand expanding and beading without showing cracks or flaws.
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
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