Page 151 - Well Control for Completions and Interventions

Well Control Surface Equipment 143

• If used, the drilling spool can be positioned below or between the
ram preventers. It must have two side outlets of at least 2 in. nomi-
nal diameter.
There are several possible configurations where an annular pre-
venter and two pipe rams are used. One option is to place the blind
ram below the pipe ram with the drilling spool between the two-ram
preventers. Positioning the blind ram at the bottom allows pipe to be
placed in the pipe ram to back-up a leaking blind ram. In addition,
the pipe rams can be changed or the annular seal replaced and the
blind ram closed.
An alternative configuration places the drilling spool between the
annular preventer and the ram preventers. When configured this way,
it is common to place the bind rams above the pipe rams. This allows
the tubing or drill string to be hung off in the pipe rams and the blind
rams closed.
3. Configuration for 10,000 15,000, and 20,000 psi working pressure BOP
stacks
The minimum requirements for 10,000 15,000, and 20,000 psi
BOP stacks is to have:
• Annular preventer.
• Three ram type preventers (usually a double ram and a single ram
preventer).
• Kill and choke lines can be connected to the BOP ram outlets pro-
viding they meet the required dimensional requirements—nomi-
nally 3 in. diameter.
• If a drilling spool is used it should have two outlets, one of
3 in. nominal diameter, and a second with a 2 in. nominal
diameter.
The stack can be configured with a double ram preventer block
below the annular preventer and immediately above a drilling spool.
A single ram preventer is positioned below the drilling spool. Placing
the blind (or blind shear) ram between the two pipe rams (above the
drilling spool) allows pump in and bleed off with the blind ram
closed. Some operators recommend having a second pressure moni-
toring and emergency kill line below the lowest ram. In a situation
where the bottom pipe ram needs to be closed it would still be possi-
ble to monitor well pressure. It could be used to perform a bullhead
or lubricate and bleed well kill.