01. valve design and manufacturing : as per API 6D. 02. flange dimension and drilling : as per ANSI b 16.5 up to 24 dn (for 22 dn-mss sp 44) & as per ANSI b 16.47 (series-a) for 26 dn and above. 03. face to face dimension : as per ANSI b 16.10. 04. materials of construction : (a) body, bonnet & cover: Forged steel ASTM a105. (b) ball: Forged steel ASTM a105 with 0.003 electroless nickel plating. (c) stem: Forged steel ASTM a105 with 0.003 electroless nickel plating. (d) seat: PTFE. (e) seat retainer: ASTM a182-f316. (f) bolting: ASTM a193-b7 and ASTM a194-2h for bolts and nuts respectively. (g) seal: Primary seals electroless nickel coated, secondary nitrile o-rings (double block and bleed Show More