Subsea blowout prevention (BOP) equipment
The subsea BOP equipment may comprise either a single stack or a two-stack system. The single stack system is preferred. The single stack system consists of one large bore BOP stack (generally 18 3/4") with a working pressure classification of 10,000 psi or 15,000 psi.
The two-stack system consists of a 2000 psi WP large bore BOP stack (generally 21 1/4") and a smaller bore stack (generally 13 5/8") with a working pressure classification sufficient to meet the maximum anticipated surface pressure.
A . . .