Page 351 - Practical Well Planning and Drilling Manual

Section 3 revised 11/00/bc 1/17/01 12:00 PM Page 327

3.1.7
Well Control [ ]

4. Two dual purpose kill and choke lines, both connected from the
drilling spool to the kill line and choke manifold. If dual-purpose
lines are not used, the stack will have one dedicated kill and one
dedicated choke line.

10,000 psi WP classification.

1. One annular preventer with a working pressure of 10,000 psi.
However, a 5000 psi annular preventer on a 10,000 psi WP BOP
stack is acceptable on existing stacks.
2. Three single, or one double and one single ram preventers. One
must have blind/shear rams, one fixed pipe rams, and the third
either fixed or variable rams. If a double ram unit is used, it should
be on top so there is room to land a tool joint on the bottom rams.
3. One full opening drilling spool with two 3 1 /16 in bore side outlets.
However, if the middle and lower ram units are equipped with
proper sized side outlets, the drilling spool may be omitted and the
kill and choke lines connected to the lower preventer outlets.
4. Two dual purpose kill and choke lines, both connected from the
drilling spool to the kill line and choke manifold. If dual-purpose
lines are not used, the stack will have two dedicated kill and two
dedicated choke lines. In this case, each line will have two full-bore
valves, the outer of each choke line hydraulically operated. The
lower kill and choke lines connected below the bottom ram shall
act as spares.

15,000 psi WP classification. This may be a 3-ram unit of identi-
cal configuration to the 10,000 psi stack, except the annular preventer
is rated to 10,000 or 15,000 psi and the BOP stack to 15,000 psi.
A 4-ram setup is preferable (though the 3-ram stack is acceptable, as
was outlined in the previous subsection, “10,000 psi WP classification”).
In this case the fourth ram unit may have fixed or variable pipe rams
installed; however, at least one ram unit must have fixed pipe rams.

3.1.7. Surface Stack Control System Specifications

An independent automatic accumulator unit of 3000 psi WP with
a control manifold showing “open” and “closed” positions for preven-

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