ASTM A234 specification covers wrought carbon steel and alloy steel fittings of seamless and welded construction covered by the latest revision of ASME B16.9, B16.11, MSS-SP-79, MSS-SP-83, and MSS-SP-95. These fittings are for use in pressure piping and in pressure vessel fabrication for service at moderate and elevated temperatures.
| Grade | C | Mn | P | S | Si |
| WPB | 0.3 | 0.29-1.06 | 0.05 | 0.058 | 0.1min |
| WPC | 0.35 | 0.29-1.06 | 0.05 | 0.058 | 0.1min |
| WP11 CL1 | 0.05-0.15 | 0.30-0.60 | 0.03 | 0.03 | 0.50-1.00 |
| WP11 CL2/3 | 0.05-0.20 | 0.30-0.80 | 0.04 | 0.04 | 0.50-1.00 |
| Grade | Cr | Mo | Ni | Cu | V | Nb |
| WPB | 0.4 | 0.15 | 0.4 | 0.4 | 0.08 | 0.02 |
| WPC | 0.4 | 0.15 | 0.4 | 0.4 | 0.08 | 0.02 |
| WP11 CL1 | 1.00-1.50 | 0.44-0.65 | - | - | - | - |
| WP11 CL2/3 | 1.00-1.50 | 0.44-0.65 | - | - | - | - |
GENERAL NOTE:
All values are maximum unless otherwise indicated.
| Tensile Requirements | WPB | WPC, WP11CL2 | WP11CL1 | WP11CL3 |
| Tensile Strength, min, ksi[MPa] | 60-85 | 70-95 | 60-85 | 75-100 |
| (0.2% offset or 0.5% extension-under-load) | [415-585] | [485-655] | [415-585] | [520-690] |
| Yield Strength, min, ksi[MPa] | 32 | 40 | 30 | 45 |
| [240] | [275] | [205] | [310] |
Where the wall thickness lies between two values above, the min elongation value is determined by the following equations:
Longitudinal E=48t+15.00
Transverse E=32t+10.00
E = elongation in 2in [50mm], %
t = actual thickness of specimen, in [mm]
