1.1This specification covers wrought-carbon steel butt-welding seamless or welded fittings specially processed to ensure better notch toughness than that to be expected in fittings manufactured to the requirements of Specification A234/A234M.
1.1.1Included are elbows, caps, tees, reducers, and other type fittings covered by ASME B16.9.
1.1.2Heat treatment is required for all fittings.
1.1.3Fittings with mandatory radiographic examination of welds are included.
1.1.4Supplementary requirements are provided for use when additional testing or examination is desired.
1.1.5Cast fittings, and fittings formed from all weld metal, are not included.
1.2Several type of fittings are provided, as follows:
| Type | Heat Treatment
Required | Weld Seam
Finish (5.3.2) | Radiography
Required? |
| |
| 30 | normalize | UW-35 | no |
| 31 | normalize | UW-35 | yes |
| 32 | normalize | UW-35 and ground flush | yes |
| 40 | normalize and temper | UW-35 | no |
| 41 | normalize and temper | UW-35 | yes |
| 42 | normalize and temper | UW-35 and ground flush | yes |
| 50 | quench and temper | UW-35 | no |
| 51 | quench and temper | UW-35 | yes |
| 52 | quench and temper | UW-35 and ground flush | yes |
1.3It shall be the responsibility of the purchaser to determine whether material meeting the requirements of this specification is satisfactory for the service application.
1.4This specification is expressed in both inch-pound units and SI units. However, unless the order specifies the applicable “M” specification designation (SI units), the material shall be furnished to inch-pound units.
1.5The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.