Design, manufacture and test standard
API Spec 16A (3th) (16A-0100): specification for drill-through equipment
API spec 6A (20th) (6A-0474): Specification for wellhead & X-tree Equipment
NACE MR0175-2003/ISO 15156: Petroleum and natural gas materials in H2S environments
A "BOP Stack" is a set or group of "blowout preventers" that are found on every oil and natural gas drilling rig as well as the oil and/or natural gas well. BOP stack is typically located below the rig floor and after the drilling rig is removed, is at the top of the well.A set of two or more BOPs used to ensure pressure control of a well.
A typical?BOP stack might consist of one to six ram-type preventers and, optionally, one or two annular-type preventers.?
A?typical stack configuration has the ram preventers on the bottom and the annular preventers at the top. The configuration?of the stack preventers is optimized to provide maximum pressure integrity, safety and flexibility in the event of a well?control incident. It is common to have an annular preventer or two on the top of the stack since annulars can be closed .
over a wide range of tubular sizes and the openhole, but annular preventers are typically not rated for pressures as high?as ram preventers.The BOP stack also includes various spools, adapters and piping outlets to permit the circulation of?wellbore fluids under pressure in the event of a well control incident.