Unison Valves Pvt Ltd offers Carbon Steel Three Piece Design S/E, S/W, B/W Ball Valve. Unison Valves Pvt Ltd is an ISO 9001:2000 certified company. Carbon Steel Three Piece Design S/E, S/W, B/W Ball Valve has IS 9890-1981 as the design standard. The pressure testing stands at BS 6755 Part I/API 598/IS 6157-1981. The screwed dimensions are ANSI B 1.20.1/BS 21/IS 554. The Socket Weld Dimensions are ANSI B 16.11/BS 5351/ IS 4712. The butt weld dimensions are ANSI B 16.25/BS 5351/ IS 11790.