MPD Riser Stack Integration Challenges - 2H Offshore
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Transcript of MPD Riser Stack Integration Challenges - 2H Offshore
Rio de Janeiro, Brazil
18-20 August 2015
MPD Riser Stack Integration Challenges SPE Workshop
Managed Pressure Drilling and Well Control
Mark Nolet
2H Offshore Inc.
Learn more at www.2hoffshore.com
Outline
• Introduction
• Integration Challenges
– OEM Connectors
– LS vs NLS
– Geometry
– Buckling
– Pressure Balance
• Conclusions
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Challenge:
• Connect MPD riser stack
components into the drilling riser
string
– RCD
– Annular Device
– Flowspool
Solution?
• Crossover Adapters
• Should be EASY right!
>> THINK AGAIN
Riser Stack Integration – Crossover Adapter
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Why so challenging?
• Lots of different players
• Lots of different riser types
• Many geometry changes
– Orientation of aux lines
– Size of aux lines
– Offset from centerline
Why is this so important?
• Usually the last item to get ordered
• Usually on critical path
Crossover Adapters
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Who Supplies End Connectors?
MPD End Connector
MPD Supplier
Riser End Connector
Riser OEM
Drilling Contractor
Donor Joint
Operator
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Load Sharing vs. Non-Load Sharing
• Load Sharing (LS)
– Tension: ~70% main pipe & 30% aux lines
• Non-Load Sharing (NLS)
– Tension: 100% main pipe only
• Most risers have some degree of LS
• MPD Riser Stack is NLS
Impact on Design
Load rating of the crossover?
For LS Riser, MPD stack may need
thicker main pipe
Impacts weld prep to OEM connector
Riser Connecter Type 100%
70% 15% 15%
Lower
Crossover
Adapter
Standard
Riser Joint
0% 0%
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• MPD Joint vs. Std Riser Joint
• Orientation of aux lines
• Size of aux lines
• Offset from centerline
Auxiliary Line Orientation Key: Choke & Kill Mud Booster Hydraulic
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Buckling of Auxiliary Lines
• Buckling Challenges:
– Mild to severe bends
– Compressive loading due
to internal pressure acting
on pipe ends
• Solutions
– Minimize severity of bends
– Increase W.T.
– Add clamps
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Crossover Adaptors
• Pressure Load Imbalance
– Pressure imbalance due to line size change
– Enlarges compressive and torsional loads
– Net axial load must be restrained
30 kips
68 kips
Net Load of 38 kips transferred to Riser Connector or Clamp
Smaller
Surface
Area
Larger
Surface
Area
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Conclusions
• Crossover Adaptors are often complex
• Allow enough time for crossover design
• Allow enough time for logistical issues
• Start as soon as the rig is identified!
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THANK YOU
QUESTIONS?
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