MPD Presentation - TUNA PRE SPUD MEETING

Report
Pressurized Mud Cap Drilling for
Premier Oil
Ardia Karnugroho
January 9, 2013
© 2013 Weatherford. All rights reserved.
1
Outline
• Safety / Drivers
• Pressurized Mud Cap Drilling (PMCD)
• Equipment
• Rig Up
• Procedures
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2013 Weatherford. All rights reserved.
2
Safety / Drivers
• Optimize drilling process by drilling with a
closed-loop drilling system.
• Returns-flow-control reduces risk to
personnel and the environment from drilling
fluids and well control incidents.
• To be able to conduct Pressurized Mud Cap
Drilling (PMCD)
• Basic well control, surface diverter
techniques, and other rig equipment remain
unchanged.
© 2012
2013 Weatherford. All rights reserved.
3
Pressurized Mud Cap Drilling (PMCD)
Permits safe and efficient
drilling in total loss zones.
• No returns to surface (returns
flow into the formation)
• Viscous fluid is pumped at low
rate down the annulus at just
below reservoir pressure
• Disposable drilling fluid (normally
water) is pumped down drillstring
• Annular back-pressure is used to
balance the reservoir pressure
and maintain system balance.
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2013 Weatherford. All rights reserved.
4
Conventional Drilling
• Drilling fluid is pumped
down the drillstring,
and returns to the
surface via the annulus
• The annulus
hydrostatic column is
weighted to exceed the
reservoir pressure and
prevent any flow into
the wellbore
• Losses are tolerable
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2013 Weatherford. All rights reserved.
5
Drilling with Mud Losses
• Drilling fluid is pumped
down the drillstring, as
further loss zones are
uncovered
• Increased losses
mean little or no mud
returns to the surface
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2013 Weatherford. All rights reserved.
6
Drilling with Total Losses
• Drilling fluid is pumped
down drillstring, but nothing
returns to surface. Fluid
column drops, reducing
BHP, compromising
primary well control and
leading to a kick.
• BOP has to be closed and
kick circulated out – but
increasing the mud weight
leads to more losses and
kicks. Ultimately cement
may have to be pumped or
the well abandoned.
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2013 Weatherford. All rights reserved.
7
Pressurized Mud Cap Drilling (PMCD)
• The annulus is closed at
surface with the rotating
control head. Drillstring
injection is switched to
sacrificial fluid.
• Light annular fluid is
pumped down the
annulus to maintain hole
fill and prevent annular
gas migration.
• Sacrificial fluid and
cuttings are lost to the
formation.
© 2012
2013 Weatherford. All rights reserved.
8
Pressurized Mud Cap Drilling (PMCD)
100 psi
• Permits safe and efficient
drilling in severe or total loss
zones, while allowing for the
detection of influx.
• Pore Pressure has to be
calculated in order to know
the Density of Annular Fluid
200
100 psi
RCD
Standpipe
Pressure
Annular
Pressure
Drilling Mud
Water
• Injection Test to determine
whether that injection will
continue once the switch has
been made to PMCD
• Video
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2013 Weatherford. All rights reserved.
9
Equipment
• Equipment Required
– Model 7875 Docking Station Rotating Control Devices
(RCD)
– Valves and Hoses
– Riser Crossover – MR-6C
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2013 Weatherford. All rights reserved.
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Model 7875 DS RCD
• Certified API 16 RCD compliant
• 2000 PSI Static Rating
• Removable Bearings With Dual
Sealing Elements
• Hydraulic Latch
• Minimum ID: 18.75”
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2013 Weatherford. All rights reserved.
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Model 7875 DS RCD
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2013 Weatherford. All rights reserved.
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Model 7875 DS RCD
RCD Hydraulic Control System
RCD Human Machine
Interface
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2013 Weatherford. All rights reserved.
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Model 7875 DS RCD
Bearing
Assembly
Running Tool
Protective
Sleeve Running
Tool
Test Plug
Pneumatic
Control Panel
Protective Sleeve
Starter
Mandrel
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2013 Weatherford. All rights reserved.
14
Rig Up
• PMCD / RCD stack will be pre-assembled offline.
• Conduct toolbox talk with the rig crew before commencing.
• RCD stack consisting of Riser Adapter Crossover, Model 7875
DS RCD and valve manifolds is assembled in the moonpool area.
• Install or prepare the hoses for the required setup and secure with
the rig tugger lines.
• During installation, the RCD stack up will be picked up from BOP
crane and connection to the riser slip joint is made. A separate lift
is required to install the mud funnel which is transferred through
the rig floor to be installed on the RCD top flange.
• The BOP crane will be dedicated during this time until full
installation of the PMCD stack is installed.
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2013 Weatherford. All rights reserved.
15
Rig Up
16
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2013 Weatherford. All rights reserved.
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Rig Up
17
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2013 Weatherford. All rights reserved.
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PID
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2013 Weatherford. All rights reserved.
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Bearing Assembly Installation
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2013 Weatherford. All rights reserved.
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Conventional Drilling with Bearing Assembly
D
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L
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P
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P
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2013 Weatherford. All rights reserved.
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PMCD Decision Tree
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2013 Weatherford. All rights reserved.
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Unmanageable Losses Chart
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2013 Weatherford. All rights reserved.
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Switching to PMCD
• Shutdown drillstring injection.
• Line up on of the pump for pumping seawater down the
annulus.
• Zero stroke counter. Begin annulus injection with minimum of
200gpm. Monitor RCD surface pressure, the RCD surface
pressure should increase as the lower weight seawater
displaces the mud in the annulus. Rotate and reciprocate the
drillstring if required.
• At 150psi RCD surface pressure, record volume of seawater
pumped down the annulus. Stop annulus injection and observe
RCD static pressure. Calculate formation pressure and density
of LAM required for the operation (plan for 50 to 200psi RCD
surface pressure).
© 2012
2013 Weatherford. All rights reserved.
25
Switching to PMCD
• Also, evaluate if the cause for RCD pressure increase is due to
change in annular fluid density or due to loss zone plugging/fill
up. If formation is plugging or filling up, it may be possible to
return to conventional drilling. If due to annular fluid density
change, continue with next step.
• Observe for gas migration and revise calculation for required
annulus injection rates.
• Resume pumping LAM down the annulus at minimum
100gpm.
• Line up to pump seawater (SAC) down drillstring.
• Commence pumping down drillstring at required drill rates for
effective hole cleaning.
© 2012
2013 Weatherford. All rights reserved.
26
Switching to PMCD
• Observe for signs of gas migration with the lowered annulus
injection rate. If gas migration is observed, increase pump rate.
• If no gas migration observed, stop annulus injection, monitor
well and opt for continuous annulus injection.
• Commence drilling in PMCD mode.
© 2012
2013 Weatherford. All rights reserved.
27
Drilling Ahead with PMCD
• Annular fluid must be injected to maintain BHP and stop gas
migration.
• Pump down drillstring at required drill rates for effective hole
cleaning (200-300gpm) or as per DSV recommendation.
• Maintain annulus pressure within the PMCD well control
matrix.
• Monitor torque and drag for hole cleaning, pump high-viscosity
pill every half stand as per Premier Oil drilling program.
• Extra high-viscosity sweeps may be pumped if torque and drag
(T&D) become excessive.
© 2012
2013 Weatherford. All rights reserved.
28
Drilling Ahead with PMCD
• Do not exceed 10m/hr drilling rate of penetration.
• Monitor SPP and Annulus Pressure.
• Cementing pump lined up to pump LAM down injection line for
emergency.
© 2012
2013 Weatherford. All rights reserved.
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PMCD Drilling – No Injection
D
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L
L
P
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E
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2013 Weatherford. All rights reserved.
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PMCD Drilling – Injection
D
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L
L
P
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P
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2013 Weatherford. All rights reserved.
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PMCD Well Control Matrix
PMCD Well Control Matrix
RCD Surface
Pressure
Well Control
Action
Green
Yellow
Red
0 to 200psi
Manageable
Pressure/
Continue Drilling
200 - 350psi at 100rpm
Greater than 350psi
Investigate cause of RCD pressure
Shut-in on rig BOP.
increase. Possible causes are listed but
Similar to yellow zone, further actions
not limited to:
to be taken will depend on the cause

Fractures plugging: switch back to
of the annulus pressure increase.
conventional drilling (Standpipe
e.g.
pressure will increase)

Fracture plugging: Return to

Gas migration: increase annulus
conventional drilling
injection rate

Gas migration: bullhead at high

Higher
than
expected
pore
rates through the kill line
pressure:
increase
annulus

High pore pressure: increase
injection fluid weight
annulus injection fluid weight
40% or lesser of the Marine Riser Pressure Rating (500psi)
40% to 70% of the Marine Riser Pressure Rating
Above 70% of the Marine Riser Pressure Rating
© 2012
2013 Weatherford. All rights reserved.
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