This document specifies the technical delivery conditions for unalloyed or low-alloy steel seamless and welded pipeline fittings for use in pipeline transportation systems for the petroleum and natural gas industries as defined in ISO°13623.

This document is applicable to welding-end fittings such as elbows, caps, tees, single or multiple extruded headers, reducers, and transition sections made from seamless and welded pipe of unalloyed or low-alloy steels.

This document specifies two classes of fitting one related to material used in non-sour service and one for material to be use in sour service environment as shown in Table°1.

This document is not applicable to the selection of the fitting class.

This document is not applicable to the materials for, or the attachment of, factory-welded extensions.