I Deepwater Subsea Equipment Section 11
1.0 Subsea BOP Stack - Arrangement - A
Features
· • Two routes to circulate
kick with upper pipe rams
closed.
• One route to circulate kick
with middle pipe rams
closed
Upper
• No outlet below lower
Annular
ram.
• Can hang off on 1 pipe
ram and shear pipe or use
Connector 2 pipe rams if using an
extended double.
• Can pump down sheared
pipe.
Lower
Annular
uoc UIC
!<®! Blind Shear
LOC LIC
!<®~ Upper Pipe
Ram (UPR)
Middle Pipe
Ram (MPR) ~@)~
0 0
Lower Pipe
Ram (LPR) !<®!
Connector
© Ji?! In-Spec Inc. 2000 11-1 General Stacking Considerations
I Deepwater Subsea Equipment Section 11
2.0 Subsea BOP Stack - Arrangement - B
Features
• Two routes to circulate kick
with upper & middle pipe
rams closed.
• One route to circulate kick
with lower pipe rams closed
• Outlet below lower ram.
Upper • Can hang off on 2 pipe rams
Annular and shear pipe or use any 3
pipe rams if using an
extended double.
• Can pump down sheared
Connector
pipe.
Lower
Annular
voe UIC ;®;
0 0
Blind Shear
~®~
Upper Pipe
0 0
Ram (UPR)
~®~
LOC LIC Middle Pipe
Ram (MPR)
~®~
Lower Pipe
Ram (LPR)
Connector
@ Ii!! In-Spec Inc. 2000 11·2 General Stacking Considerations
I Deepwater Subsea Equipment Section 11
3.0 Subsea BOP Stack - Arrangement - C
Features
• Three, 2 or 1 routes to
circulate kick with respective
upper, middle, or lower pipe
rams closed.
• Outlet below lower ram.
Upper • Can hang off on 2 pipe rams
Annular and shear pipe or use any 3
pipe rams if using an extended
double.
• Can pump down sheared pipe.
Connector
Lower
Annular
Blind Shear 0
0
0
0
DOC DIC !®)o Upper Pipe
Ram (UPR)
~~
Middle Pipe
Ram (MPR)
LOC LIC ~®)o Lower Pipe
Ram (LPR)
Connector
© Ii?! In-Spec Inc. 2000 11-3 General Stacking Considerations
j Deepwater Subsea Equipment Section 11
4.0 Subsea BOP Stack - Arrangement - D
Features
• Upper and Lower
Annular is on the
LMRP.
• Stack height is
reduced (and LMRP
Upper
height is increased) to
Annular
allow shorter rig
substructure height.
Lower • Can not pump down
Annular sheared pipe
Connector
!®)! Blind Shear
uoc UIC
~®)i Upper Pipe
Ram(UPR)
;®)~
0 0
Middle Pipe
Ram(MPR)
Lower Pipe
Ram(LPR) ~®)~
0 0
Connector
@ Ii!! In-Spec Inc. 2000 11-4 General Stacking Considerations
I Deepwater Subsea Equipment Section 11
5.0 Subsea BOP Stack - Arrangement - E
Features
• Upper Inner and Outer Kill
Valves below the Upper
Annular.
Upper • C/K Isolation Valves are on
Annular the LMRP package. Note:
these valves are "normally
open".
C/K Isolation
C/K Isolation
Connector
Lower
Annular
0
0
0 Blind Shear
0
voe UIC ~~o Upper Pipe
0 Ram(UPR)
~®~
Middle Pipe
Ram(MPR) 0 0
LOC LIC
!®! Lower Pipe
Ram (LPR)
Connector
@ Rf In-Spec Inc. 2000 11-5 General Stacking Considerations
I Deepwater Subsea Equipment Section 11
UNITED STATES DEPARTMENT OF THE INTERIOR
MINERALS MANAGEMENT SERVICE
GULF OF MEXICO OCS REGION
NTL No. 99-G09 Effective Date: May 10, 1999
NOTICE TO LESSEES AND OPERATORS OF FEDERAL OIL. GAS. AND SULPHUR
LEASES IN THE OUTER CONTINENTAL SHELF. GULF OF MEXICO OCS REGION
Location of Choke and Kill Lines on BOP Stacks
This Notice to Lessees and Operators (NTL) supersedes the Letter to Lessees and Operators, dated November
17, 1994, on this subject. It updates regulatory citations and includes a statement on the Paperwork Reduction
Act of 1995.
The purpose of this NTL is to specify the location of the choke and kill lines serving blowout preventer (BOP)
stacks. This is necessary because the requirements at 30 CFR 250.406 (oil and gas drilling operations), 250.515
(oil and g~s well-completion operations), 250.615 (oil and gas well-workover operations), 250.1610 (sulphur
drilling operations), and 250.1624 (sulphur well-completion and well-workover operations) do not specify their
exact location.
Operators usually install the choke and kill lines above the bottommost ram. However, some operators have
requested to install them below the bottommost ram. For choke lines, this is not acceptable. Failure of a choke
line installed below the bottommost ram could result in a blowout because this configuration does not provide a
backup system for proper well control.
Therefore, the Gulf of Mexico OCS Region District Offices will not approve an Application for Permit to Drill
(APD) or a Sundry Notice and Report (Sundry) to conduct well-workover operations that indicates a BOP stack
with a choke line installed below the bottommost ram. However, they may approve your requests to install a
kill line below the bottommost ram. You must include a schematic drawing of the BOP stack and choke and kill
lines with any APD or well-workover Sundry if the tree is to be removed.
Paperwork Reduction Act of 1995 Statement
This NTL refers to the collection of information on forms MMS-123 and MMS-124. The Office of
Management and Budget (0MB) has approved the information collection requirements for these forms and
assigned 0MB Control Nos. 1010-0044 and 1010-0045, respectively. This NTL does not impose additional
information collection requirements subject to the Paperwork Reduction Act of 1995.
Contact
If you have any questions on this NTL, you may contact Mr. Bill Martin at (504) 736-2849.
Chris C. Oynes
Regional Director
@ Ii!! In-Spec Inc. 2000 11-6 General Stacking Considerations
