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2 The Need for Standardising Deepwater Riser Systems? Frank Lim and Tim Eyles OFFSHORE DRILLING & DEEPWATER/UNDERWATER TECHNOLOGIES November 2006 Kuala Lumpur MALAYSIA

3 Background Designs of deepwater risers have largely been selected by functional specifications and on a single development basis Technical solutions have been driven by the EPCI contractors, resulting in a wide range of solutions with little or no commonality between projects This approach is engineering intensive, riddled with risks due to: Technical complexity Degree of novelty Contractor technical capability Qualification testing uncertainty Interface sensitivity Schedule criticality Slide No. 2

4 Deepwater Riser Types Drilling and Completion Risers Production, Export and Service Risers Flexible Steel Catenary Free Standing Vertically Tensioned Slide No. 3

5 Top Tensioned Risers (Dry Trees) TLP Spar Slide No. 4

6 Steel/Flexible Catenary Riser Slide No. 5

7 Bundled Hybrid Riser Tower Slide No. 6

8 Single Line Offset Riser (SLOR) Slide No. 7

9 Modular SLOR Aircan Module SLOR lends itself most readily for MODULARISATION Response insensitive to platform motions Deeper water depth reached by longer steel pipe string Shallow water flexible pipe jumper independent of water depth Pipe Foundation Module Slide No. 8

10 Variants of Single Line SLOR Single Line Offset Riser Production, Gas Injection Water Injection COR Concentric Offset Riser Production Riser Base Gas Lift Active Heating N 2 or Vacuum Insulation Slide No. 9

11 Typical Component Modules Slide No. 10

12 Standardised Aircans Slide No. 11

13 Standardised Foundations Slide No. 12

14 Standardised Component Modules Lower Offtake Assembly Upper Gooseneck Assembly Slide No. 13

15 Building Blocks to Form a Riser System Slide No. 14

16 Standardisation Potential MODULES Riser Size Outer Pipe Size STANDARD All Risers Riser Service SLOR & 8 COR / / 8 10¾ 12¾ 8 10¾ 12¾ 13¼ 15½ Suction Anchor Offtake Spool Assembly Rigid Jumper Assembly Crossover Joints Gooseneck Frame Assembly Adjustment for Each Riser Length Strength Frame & Link Buoyancy Can Flexible Jumper COR only 10¾ 12¾ 13¼ 15½ GL Crossover Spool Assembly GL Hanger Spool Assembly GL Jumper Slide No. 15

17 Modular SLOR Strategy Develop commercially and technically robust solutions (Non optimised) Ensure installation from wide range of vessels Enable pipe installation by any method (reel, weld, tow, thread) Operator assumes global design responsibility (structural and thermal) Standardise key interfaces Incorporate Contractors input prior to ITT Accept only minor deviations from issued ITT design Contractors accept installation responsibility Slide No. 16

18 Modular SLOR - Rationale Differentiate on ability to install pipe efficiently NOT ability to: Conduct global design Conduct detail design riser products/components Installation of top and bottom modules (no different in size to PLETS) Allows Operator to drive technical solution and gets what it wants/needs Risk & responsibility fairly apportioned to those that can manage it Operator Global & component performance Contractors Installation responsibility Slide No. 17

19 Commercial Benefits System configuration engineered once, covering most field requirements, thereby reducing engineering schedule and manhours Increased market competition between installation vessels, becoming less dependent on the major contractors and subject to higher costs Flexible procurement and manufacturing route, as multiple suppliers can be approached for obtaining competitive commercial offers; Easier planning allowing wider application of available installation vessels Component standardisation reduces equipment qualification testing Robust and simplified designs allow for more in-country content Improved bid schedules, contractor tenders and accuracy in budgets based on increased levels of engineering Common spares and stock inventory for call-off as required Lessons learnt in all processes (engineering, manufacturing, procurement and installation) are transferable to future developments Slide No. 18

20 Caution Standardisation will initially increase the riser hardware cost slightly owing to the need of built-in conservatism in the component design to cater for a range of services Initial cost increase estimated to be 5-10% over the cost of a tailored and highly optimised riser system This cost is likely to fall significantly, by some 30% or more, once the supply chain has got used to the idea, understood the market requirements and become competitive (as seen in the standardisation of subsea equipment) Slide No. 19

21 Summary Standardisation and Modularisation deliver a robust and adaptable riser that has commonality and interchangeability of component modules Approach offers greater market place competition, resulting in improved quality, schedules and potentially overall field development cost savings Viable technical and commercial solution in the majority of deepwater applications Basis of development plan by a supper major in West Africa Slide No. 20