effective cost saving strategy for rigmove operations · 2 effective cost saving strategy for...

Effective Cost Saving Strategy for Rigmove OperationsDuncan Cuthill : Viking SeaTech

2 Effective Cost Saving Strategy for Rigmove Operations

Challenges

• Minimise Rigmove TimeNon-operational downtime.

• Minimise RiskTo Personnel, subsea assets,rigs and vessels.

• Eliminate Errors inMooring Operations

Eastern Mediterranean

3 Effective Cost Saving Strategy for Rigmove Operations

Project Overview

Eastern Mediterranean

• Conventionally chain-mooredsemi-submersible

• Multiple well locations withcomplex seabed infrastructure

• Prior experience of problematicand protracted mooring operations

• Solution required to improve andoptimise the rig move process

4 Effective Cost Saving Strategy for Rigmove Operations

Location and Operational Challenges

• Risks to subseaInfrastructure

4 Effective Cost Saving Strategy for Rigmove Operations

Location and Operational Challenges

• Risks to subseaInfrastructure.

• Site soil conditionsand bathymetry

4 Effective Cost Saving Strategy for Rigmove Operations

Location and Operational Challenges

• Risks to subseaInfrastructure.

• Site soil conditionsand bathymetry

• Variance inwater depth

4 Effective Cost Saving Strategy for Rigmove Operations

Location and Operational Challenges

• Risks to subseaInfrastructure.

• Site soil conditionsand bathymetry

• Variance inwater depth

• Semi submersiblehas a chain mooringsystem

5 Effective Cost Saving Strategy for Rigmove Operations

Conventional Mooring : Operational Issues

Two vessels required for installation& recovery of each mooring line.

1. Secondary vessel required to “J hook” andsupport mooring line.

2. High loads at AHV Stern Roller.

3. Damaged / lost anchors and damaged mooringwires during AH operations.

4. Increased risks to personnel working on deck.

5. Significantly increases rig move time.

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.

Viking SeaTech Solution : Preset Mooring Strategy

6 Effective Cost Saving Strategy for Rigmove Operations

Increased Efficiency & Reduced Cost

7 Effective Cost Saving Strategy for Rigmove Operations

Viking SeaTech Mooring Solution - Advantages

Simple system design

Standard components and connections

Reduced system weight

Decreased risk to personnel, vessels and infrastructure

Enhanced station keeping abilityReduced unit offsets reduce drilling downtime

Mooring system integrity is assured prior to rig arrival

No operational delays due to anchoring or AHV problems

8 Effective Cost Saving Strategy for Rigmove Operations

Project Summary : Comparative Project Time Estimate

9 Effective Cost Saving Strategy for Rigmove Operations

Conventional mooringscenario rigmove cost $6,394,000

9 Effective Cost Saving Strategy for Rigmove Operations

Conventional mooringscenario rigmove cost $6,394,000

Preset strategy rigmove cost $2,731,200

9 Effective Cost Saving Strategy for Rigmove Operations

Conventional mooringscenario rigmove cost $6,394,000

Preset strategy rigmove cost $2,731,200

Average Cost Saving perWell over 4 well programme $3,000,000

9 Effective Cost Saving Strategy for Rigmove Operations

Conventional mooringscenario rigmove cost $6,394,000

Preset strategy rigmove cost $2,731,200

Average Cost Saving perWell over 4 well programme $3,000,000

Direct cost savings $12,000,000

10 Effective Cost Saving Strategy for Rigmove Operations

Comparative Models – 4 Wells

• 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

duncan.cuthill@vikingseatech.com01224 914 7223