Introduction to API 6A flanges – 6B AND 6BX

API 6A standard is developed for the American Petroleum Institute. The API 6A specification shares many characteristics with ANSI/ASME flanges. Despite being dimensionally similar, their minimal design requirements for operating pressure begin in the 2000#. Certain jobs require the use of pressure classes as high as the 6BX 25000#, though this is much less common than the typical 6B range of 5000# and below.

All API flanges require ring type joint facings with the proper gaskets for optimal integrity of their application.This higher-pressure base requirement is due to their overwhelmingly popular use in petrochemical / oilfield applications of a volatile nature. Upstream assemblies with API flanges consist of wellheads, drilling equipment, and much more. The downstream sectors of refinery and processing also require these flanges for the development of crude oil into products for the everyday consumer.

API 6A Weld Neck Flanges

6B flanges are of the ring joint type and are not designed for face-to-face make-up.The connection make-up bolting force reacts on the metallic ring gasket.The size from 2-1/16″ to 21-1/4″ and pressure 2000#,3000# and 5000#.

6BX flanges are of the ring joint type and designed with a raised face. Depending on the tolerances, the connection make-up bolting force may react on the raised face of the flange when the gasket has been properly seated. This support prevents damage to the flange or gasket from excessive bolt torque.The size from 2-1/16″ to 21-1/4″ and pressure 10000#,15000# and 20000#.

Haihao Group has many years’ experience for export,call us or email us if you need API 6A flanges.