HTHP - A Deepwater Perspective

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2 HTHP - A Deepwater Perspective 3 rd November 2010

3 Overview The Importance The challenge Key drivers

4 Deep Offshore is a Key to Meeting Future Energy Demand

5 Courtesy: Dave Turner BP 129 Deg C Learn 149 more Deg C at Deg C 260 Deg C 260 Deg C

6 Deepwater Image Has Been Tarnished Deepwater and particularly deepwater HTHP may now be politically incorrect and considered unnecessarily risky? Salazar - Operators that play by the rules and clear the higher bar can be allowed to resume drilling. The oil and gas industry will be operating under tighter rules, stronger oversight, and in a regulatory environment that will remain dynamic as we continue to build on the reforms we have already implemented Increased scrutiny and increased equipment qualification highest standards However, despite all this energy demands means HTHP is inevitable its just when and how

7 Where is the HTHP? GOM/Brazil Sub Salt/Presalt

8 Deepwater Activity in GOM Many Operators are involved

9 A Range of Riser Configurations Are Needed Dry Completions Top Tensioned Risers (TTR) to TLPs and Spars Threaded and flanged construction 9in to 16in Production 18in to 24in Drilling Subsea Completions Steel Catenary Risers (SCR) Welded construction Production, Service, Export Flexible risers Production, Service, Export

10 HTHP How Big is the Problem? Problem Relative Magnitude HP >10,000psi Internal Shut-in Deep Water HT >121 Deg C Max Operating Temp Corrosive conditions

11 Extreme Wall Thicknesses - SCR Pipe Wall Sizing OPT USA /4 INCH OD Nominal Wall Thickness Comparison for API 1111 & 2RD Codes 10,000ft Water Depth, 300kg/m3 Fluid, 135 Deg C Design Temp X65 Grade Pipe, 3mm Corrosion Allowance, 12 Deg Top Angle Wall Thickness (mm) Pipe Manufacturing Limit? ,000 10,000 15,000 Design Pressue at Mudline (psi) API-1111 API 2RD

12 Why is Deep Water such an Issue for HPHT? Extreme tensions compound the wall thickness requirements Results in loads at the limit of: Installation vessels Host production vessels Introduces fatigue issues from fluctuating axial loads Thicker walls Impact pipe weldability Increased cycle times Reduced fatigue performance Reduced pipe availability Reduced flow area

13 Why is corrosion such a problem? Its not just sea water BUT more importantly internal fluids Different types of corrosion: O 2 CO 2 H 2 S It impacts every aspect of a development from design, material specification, manufacture, installation and operation Increases payload, reduces fatigue life, increases schedule, reduces lay rate, increases installation cost. Its complexity increases uncertainty and risk

14 CO 2 Corrosion (Sweet Corrosion) Corrosion Rate vs Partial Pressure and Temp Heavy Pitting and General Wall Loss Corrosion rate (mm/year) Corrosion rate (mm/year) Partial pressure of CO 2 (MPa) Temperature of 25 C Temperature ( C)

15 H 2 S Corrosion (Sour Corrosion) Steel reacts with hydrogen sulphide, forming iron sulphide and atomic hydrogen Fe + H 2 S > FeS + H 2 Atomic H diffuses into the metal matrix causing cracking, blistering, delamination Under the right conditions the process can be very rapid leading to structural failure

16 Factors Affecting Sour Corrosion Partial pressures of H 2 S present ph of the production fluid Stresses in the pipe Material properties of the pipe flaws/grain structure Hardness of the steel Frequency of loading

17 Fatigue factor for Small H 2 S Concentrations In air Source: High pressure riser designs for ultra deepwater; J. Murray et al,

18 Appropriate Material Selection is Required Carbon Dioxide Partial Pressure (psi) % Cr (410, F6NM) Non NACE Super Duplex Inconel 625 Increasing Cost NACE Low alloy steels H2S Partial Pressure (psi) HTHP Source : Oilfield Metallurgy Lloyd-Thomas Consultancy

19 Clad Pipe Inconel 625 Metallurgical or Mechanically Lined

20 SCR Installation The impact of increased WT and Cladding Cost Majority of SCR CAPEX is in installation 45 minutes to weld, inspect and apply insulation field joint on 12-3/4 OD x 12.7 mm wt SCR joint Increases to 100 minutes for 12-3/4 OD x 40 mm wt joint Lay rates decrease by 50% therefore installation costs increase similarly Clad pipe a further impact Installation Vessel Specification 12-3/4 OD x 40 mm wt SCR has 445 Te hang off load in 7,000 feet water depth (empty with 82 deg J lay angle)

21 What does the Industry Need? Higher strength steels 70-80ksi offshore weldable 125ksi for use with mechanical connectors Cost effective base material cladding Higher speed offshore welding (EB, Laser, Friction?) Installation vessels with higher tension capacities Qualification of HPHT interface items Flex joints, taper joints and rigid jumpers Composite materials lightness, strength and corrosion resistance Subsea HIPPS? solve some of the problems away from the complex dynamic free hanging section!

22 Summary Despite Macondo, Deepwater HTHP will go ahead, some delays should be expected, but we can use this time make sure we can do it right. Deepwater HTHP is not a linear extrapolation Material and welding technology is critical to success Corrosion is a key driver, it influences every aspect of a project Alternatives to welding are needed that are faster and can work with higher strength steel in lieu of welding advances More investment is needed to develop and qualify new technologies The HTHP problem is significant but so is the prize pan industry initiatives are necessary to share the load

23 Questions?

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