American Petroleum Institute

SPECIFICATION FOR WELLHEAD EQUIPMENT (Production Valves, Flanges, Blowout Preventers, and Wellhead Fittings) - Eighth Edition
 N STD 6A

Annotation

Coverage. This specification covers items of equipment utilized for pressure control systems required during the drilling and production life of a well. Specifically covered are the groups of equipment usually referred to as ring-joint flange., ring joint gaskets, drilling-through and flow line valves, multiple completion valves, flanged drilling through equipment, screwed wellhead equipment flanged wellhead equipment, Christmas tree equipment, flow control chokes, water sampling devices, segmented flanges, and underwater wellhead equipment, which include the following types:

Sect. 2 Ring-Joint Flanges

Type 6B: 2,- 8,- and 6,000 psi

Blind

Integral

Threaded

Welding Neck

Type 6BX: 6,-10,- and 16,060 psi

Blind (10,- and 115,000 psi only)

Integral

Welding Neck (10,- and 16,000 pal only)

Sect. 3 Ring-Joint Gaskets

Type R, RX, and BX

Sect. 4 valves, Drilling-through and Flow line

Flanged and Screwed

Sect. 5 valves, Multiple Completion

Flanged, low-line, full-bore gate and plug