Effective Cost Saving Strategy for Rigmove Operations
Duncan Cuthill : Viking SeaTech
Challenges
• Minimise Rigmove Time
Non-operational downtime.
• Minimise Risk
To Personnel, subsea assets,
rigs and vessels.
• Eliminate Errors in
Mooring Operations
Eastern Mediterranean
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Effective Cost Saving Strategy for Rigmove Operations
Project Overview
• Conventionally chain-moored
semi-submersible
• Multiple well locations with
complex seabed infrastructure
• Prior experience of problematic
and protracted mooring operations
• Solution required to improve and
optimise the rig move process
Eastern Mediterranean
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Effective Cost Saving Strategy for Rigmove Operations
Location and Operational Challenges
•
4
Effective Cost Saving Strategy for Rigmove Operations
Risks to subsea
Infrastructure
Location and Operational Challenges
4
Effective Cost Saving Strategy for Rigmove Operations
•
Risks to subsea
Infrastructure.
•
Site soil conditions
and bathymetry
Location and Operational Challenges
4
Effective Cost Saving Strategy for Rigmove Operations
•
Risks to subsea
Infrastructure.
•
Site soil conditions
and bathymetry
•
Variance in
water depth
Location and Operational Challenges
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Effective Cost Saving Strategy for Rigmove Operations
•
Risks to subsea
Infrastructure.
•
Site soil conditions
and bathymetry
•
Variance in
water depth
•
Semi submersible
has a chain mooring
system
Conventional Mooring : Operational Issues
Two vessels required for installation
& recovery of each mooring line.
1. Secondary vessel required to “J hook” and
support mooring line.
2. High loads at AHV Stern Roller.
3. Damaged / lost anchors and damaged mooring
wires during AH operations.
4. Increased risks to personnel working on deck.
5. Significantly increases rig move time.
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Effective Cost Saving Strategy for Rigmove Operations
Viking SeaTech Solution : Preset Mooring Strategy
Mooring system installed at each location prior to drilling unit arrival
System utilises Bruce DENNLA Anchors
Polyester rope / wire rope utilised in place of chain/wire combination
System capable of operating in range of water depths (400 - 1200m)
Designed to accommodate multiple mooring scenarios
Overall mooring “footprint” is significantly reduced.
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Effective Cost Saving Strategy for Rigmove Operations
Viking SeaTech Mooring Solution - Advantages
Mooring system integrity is assured prior to rig arrival
No operational delays due to anchoring or AHV problems
Enhanced station keeping ability
Reduced unit offsets reduce drilling downtime
Reduced system weight
Decreased risk to personnel, vessels and infrastructure
Simple system design
Standard components and connections
Increased Efficiency & Reduced Cost
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Effective Cost Saving Strategy for Rigmove Operations
Project Summary : Comparative Project Time Estimate
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Effective Cost Saving Strategy for Rigmove Operations
Conventional mooring
scenario rigmove cost
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Effective Cost Saving Strategy for Rigmove Operations
$6,394,000
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Conventional mooring
scenario rigmove cost
$6,394,000
Preset strategy rigmove cost
$2,731,200
Effective Cost Saving Strategy for Rigmove Operations
9
Conventional mooring
scenario rigmove cost
$6,394,000
Preset strategy rigmove cost
$2,731,200
Average Cost Saving per
Well over 4 well programme
$3,000,000
Effective Cost Saving Strategy for Rigmove Operations
Conventional mooring
scenario rigmove cost
$6,394,000
Preset strategy rigmove cost
$2,731,200
Average Cost Saving per
Well over 4 well programme
$3,000,000
Direct cost savings
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Effective Cost Saving Strategy for Rigmove Operations
$12,000,000
Comparative Models – 4 Wells
•
•
•
•
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24.5 days rig time saved over drilling programme – 4 wells / 6 months
Rigmove cost reduced by 47%
Circa $12 million in direct cost savings
Optimised drilling unit utilisation
Effective Cost Saving Strategy for Rigmove Operations
[email protected]
01224 914 7223