a Cu ≤ 0.50 %; Ni ≤ 0.50 %; Cr ≤ 0.50 % and Mo ≤ 0.15 %.

b For each reduction of 0.01 % below the specified maximum concentration for carbon, an increase of 0.05 % above the specified maximum concentration for Mn is permissible, up to a maximum of 1.65 % for grades ≥ L245 or B, but ≤ L360 or X52; up to a maximum of 1.75 % for grades > L360 or X52, but < L485 or X70; and up to a maximum of 2.00 % for Grade L485 or X70.

c Unless otherwise agreed, Nb + V ≤ 0.06 %.

d Nb + V + Ti ≤ 0.15 %.

e Unless otherwise agreed.

f Unless otherwise agreed, Nb + V + Ti ≤ 0.15 %.

g No deliberate addition of B is permitted and the residual B ≤ 0.001 %.

Pipe Grade

Rt0.5

Rm

Af

Rm

c The specified minimum elongation, Af, expressed in percent and rounded to the nearest percent, shall be as determined using the following equation:

where

C is 1940 for calculations using SI units and 625,000 for calculations using USC units;

Axc is the applicable tensile test piece cross-sectional area, expressed in square millimeters (square inches), as follows:

1) for circular cross-section test pieces, 130 mm2 (0.20 in.2) for 12.7 mm (0.500 in.) and 8.9 mm (0.350 in.) diameter  test pieces; 65 mm2 (0.10 in.2) for 6.4 mm (0.250 in.) diameter test pieces;

2) for full-section test pieces, the lesser of a) 485 mm2 (0.75 in.2) and b) the cross-sectional area of the test piece, derived using the specified outside diameter and the specified wall thickness of the pipe, rounded to the nearest     10 mm2 (0.01 in.2);

3) for strip test pieces, the lesser of a) 485 mm2 (0.75 in.2) and b) the cross-sectional area of the test piece, derived using the specified width of the test piece  and the specified  wall  thickness  of the  pipe,  rounded to  the  nearest  10 mm2 (0.01 in.2);

U is the specified minimum tensile strength, expressed in megapascals (pounds per square inch).