api 5000API has specified weld necks for many 6BX flanges, and not done so for many others, but API has provided the basis for determining the dimensions of a 6BX integral flangeOur ASTM A105N flange, with a size of 2-116 inches, adheres to API 6A and TYPE API 6B standards. It boasts a sturdy API 5000 PSI rating, SCH XXS thickness, and an RTJ