This International Standard specifies the requirements for a series of steel ball valves suitable for generalpurpose industrial applications. It covers valves of the nominal sizes (see ISO 6708 and ASME B16.34) ⎯ DN 8, 10, 15, 20, 25, 32, 40, 50, 65, 80, 100, 150, 200, 250, 300, 350, 400, 450, 500 (NPS 1/4, 3/8, 1/2, 3/4, 1, 11/4, 11/2, 2, 21/2, 3, 4, 6, 8, 10, 12, 14, 16, 18 and 20), and is applicable to the following pressure designations (see ISO 7268 or EN 1333, and ASME B16.34): ⎯ Class 150; 300; 600; 900 and PN 10; 16; 25; 40; 63; 100. It includes provisions for valve characteristics as follows 1): ⎯ flanged and butt-welded ends in sizes 15 u DN u 500 (1/2 u NPS u 20); ⎯ socket welding ends in sizes 8 u DN u 100 (1/4 u NPS u 4); ⎯ threaded ends in sizes 8 u DN u 50 (1/4 u NPS u 2); ⎯ body seat openings designated as full bore, reduced bore, and double reduced bore; ⎯ materials; ⎯ testing and inspection