This standard covers metal ball valves used in on-off service that have butt-welding or flanged ends for nominal pipe size 1/2 through NPS 12 and threaded or socket-welding ends for sizes NPS 1/2 through NPS 2, corresponding to the nominal pipe sizes in ASME B36.10M. This standard covers additional requirements for ball valves that are otherwise in full conformance to the requirements of ASME B16.34, Standard Class. This standard covers flanged and butt-welding end valves in Standard Classes 150 and 300 and threaded and socket-welding end valves in Standard Classes 150, 300, and 600. Figure 1 illustrates a floating ball valve and Figure 2 illustrates a trunnion-mounted ball valve. Both figures are to be used only for the purpose of establishing standard nomenclature for valve parts.