ASTM A420/A420M-00
Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low Temperature Service
Grade | Composition, % | ||||||||||
C | Mn | P | S | Si | Ni | Cu | Cr | Mo | V | Nb | |
WPL6(1)(2) | 0.30 | 0.60-1.35 | 0.035 | 0.040 | 0.15-0.30 | 0.40 | 0.40 | 0.30 | 0.12 | 0.08 | 0.02 |
WPL9 | 0.20 | 0.40-1.06 | 0.030 | 0.030 | - | 1.60-2.24 | 0.75-1.25 | - | - | - | - |
GENERAL NOTE:
All values are maximum unless otherwise indicated.
NOTES: (1) For each reduction of 0.01% C below 0.30%, an increase of 0.05% Mn above 1.06% will be permitted, up to a maximum of 1.35%. (2) Fittings made from forgings may have 1.35% max Mn.
Tensile Requirements | WPL6 | WPL9 |
Tensile Strength, min, ksi [MPa] | 60-85[415-585] | 63-88[435-610] |
Yield Strength, min, ksi [MPa] | 35[240] | 46[315] |
Wall thickness | Elongation Requirements | |||||
in | mm | Longitudinal | Transverse | |||
WPL6 | WPL9 | WPL6 | WPL9 | |||
Standard round specimen, or small proportional specimen, min % in 4D | 22 | 20 | 12 | - | ||
Rectangular Specimen for wall thickness 0.312in [7.94mm] and over, and for all small sizes tested in full section; min % in 2in[50mm] | ³0.312 | ³7.94 | 30 | 28 | 16.5 | 18 |
Rectangular Specimen for wall thickness less than 0.312in [7.94mm]; min % in 2 in[50mm] (0.5in [12.7mm] wide specimen) | 0.281 | 7.14 | 28.5 | 26.5 | 15.5 | 17.0 |
0.250 | 6.35 | 27.0 | 25.0 | 14.5 | 16.0 | |
0.219 | 5.56 | 25.5 | 23.5 | - | - | |
0.188 | 4.76 | 24.0 | 22.0 | - | - | |
0.156 | 3.97 | 22.5 | 20.5 | - | - | |
0.125 | 3.17 | 21.0 | 19.0 | - | - | |
0.094 | 2.38 | 19.5 | 17.5 | - | - | |
0.062 | 1.59 | 18.0 | 16.0 | - | - |
Where the wall thickness lies between two values above, the min elongation value is determined by the following equations:
WPL6 WPL9
Longitudinal E=48t+15.00 E=48t+13.00
Transverse E=32t+6.50 E=32t+8.00
E = elongation in 2in [50mm], %
t = actual thickness of specimen, in [mm]