Tiêu chuẩn ASME B15 9 2001 về ống thép. This Standard covers overall dimensions, tolerances, ratings, testing, and markings for factorymade wrought buttwelding fittings in sizes NPS 12 through NPS 48 (DN 15 through DN 1200). Product Details. Published: 02282013; ISBN(s):: 9780791834947; ANSI: ANSI Approved; Number of Pages: 52; File