Use of Manned Underwater Operations in Statoil. Benefits and possibilities in project execution

Transcription

1 Use of Manned Underwater Operations in Statoil Benefits and possibilities in project execution by Pål Atle Solheimsnes Leading Advisor Subsea Intervention and Diving Norwegian Oil and Gas 3. March 2016

2 Purpose for this presentation Show Statoil s strategies and governing elements for manned underwater operations Add awareness of the benefits manned underwater operations can bring to a project (modifications, repair or development project).

3 Statoil Strategy for Manned Underwater Operations Diving shall be considered as an option for all subsea operations Diving shall be chosen when beneficial based on evaluation of safety, efficiency and cost.

4 The diving history in Statoil Installation of our major production units on the NCS have been assisted by divers. After having investigated for 6 years (late 1990's) the possibility to cease diving Statoil and Hydro decided that: There was a business need for diving services It was possible to perform diving in a sustainable and beneficial way Statoil then started to work with the diving industry, both locally and internationally, to make the necessary step changes in diving. To day Statoil are performing and yearly average of 100 DSV days and a high volume of national and international surface supplied diving. The HSE statistics for diving in Statoil is good and can be compared to any other company activity. Diving is a safe and sound method for subsea intervention!

5 Statoil SAT Diving Volume Project Scope DSV days Langeled Hyperbaric welding 76 Tampen Link Hot-tap Glitne 1 Re-locate flexible flow lines 43+7 Statfjord OLS Repair 14 South Pars (Iran) Bolted tie-in M1080 Modification Gullfaks SPM2 Repair 10 Gjøa/Flags Bolted tie-in 26 P12 Hyperbaric welding 62 Statfjord C / NUI Riser replacement 55 Glitne 2 Re-locate flexible flow lines 14 Gudrun Gullfaks B Volve Gullfaks A Tie-in spools J-tube seal repair Bolted tie-in Prepare DEH pull-in in J-tube Riser pull out of J-tubes Valemon Bolted tie-in 29 Gullfaks A and C Umbilical inst. SSIV 9 Gullfaks SPM1+2 Removal Grane Y Hyperbaric welding 40 Valemon/Huldra Bolted tie-in 29 EGOP/UHGP Bolted tie-in 66 Gullfaks bundle towhead C3 Repair 6 TOTAL

6 HSE related to diving operations in Statoil NCS: No pressure related incidents since 2002 Statoil: No cases of treatment for in-water incidents Diving incidents in Statoil from synergi, only HSE (not Q) Diving volume in Statoil NCS, Inshore, International

7 Governing documentation ARIS (Statoil Internal) Marine Operations OM01.14 ARIS (Statoil Internal) Manned Underwater Operations (Norway) OM TR1244 (Statoil Internal) Technical requirements for cost estimate classes - offshore projects NORSOK U-100 / U-103 IOGP 411 Diving Recommended Practice Various relevant guidelines (IMCA)

8 Diving as a standard intervention solutions Manned underwater operations can be the preferred solution based on evaluation of safety, efficiency and cost. And not only a solution to be chosen where remote operations cannot perform the specified task

9 Reduced Cost or Added Value by Diving Less special tooling Diving preparedness Response time Flexibility Access All tasks a man can do Reduced engineering, steel, tooling Smaller spools Less protection covers CAPEX Efficiency DSV s are construction vessels Simultaneous Diving / ROV

10 Example of diving efficiency Removal operations SOW Interventions method Time Statfjord SPM removal WROV 56 days Cost GF SPM 1 removal (2014) Diving + WROV 14 days 50% reduction GF SPM 2 removal (2014) Diving + WROV 20 days 30% reduction Statfjord SPM removal was a cut operation with no re-use of subsea installations. Gullfaks SPM removals were more complex with re-use of subsea assets (OLS installation)

11 Example (Study) of diving CAPEX reduction Johan Sverdrup Phase 1 3 Subsea Templates 8 diver assisted tie-in spools to templates 4 diver assisted tie-in spools to jacket High cost saving with use of diver assisted tie-in for both phase 1 and 2 11 Classification: Internal

12 Example of diving capability M1080 project Replacement of XT sensor bolts due to wrong material quality (year ) Extremely limited access Bolts replaced by ROV on approx. 30 XTs Bolts replaced by divers on approx. 45 XTs Project cost: Use of IMR and tooling, 2,5 times the cost compared to diver intervention

13 Diving Vessel Capabilities more than just diving Modern Diving Support Vessels (DSV) are in fact well equipped subsea construction vessels, with an additional tool the divers. SKANDI ARCTIC (2016: Deep Arctic) - Deck area 1700m 2-400T SWL subsea crane - 2 WROVs + OBSROV SEVEN FALCON - Deck area 1050m 2-250T SWL subsea crane - 1 WROV + OBSROV

14 Last initiative for more efficient operations - use of 4-men bell run February 2016 Statoil used DSV Seven Falcon for Bundle repair at Gullfaks towhead C3 DSV Seven Falcon is the only DSV vessel designed and built for 4 men bell run capacity. For this operation it was the first time a 4-men bell run was carried out and thereby utilized the fully capacity at DSV Seven Falcon This bell-run showed a clear increasing of the efficiency for the Gullfaks projects When using one extra diver in the water, the generic risk increased. The risk was compensated with familization and active use of ROV if an incident occured.

15 How to capitalize on Diving? The value of diving lies in the simplification you can achieve in your seabed facilities. - Simpler design less steel (no pull-in forces) - Reduced dimensions on spools - Less protection covers - No advanced connectors and tie-in tooling - No PLET/PLEMs required - Reduced lifting weights / simplified installation - Easier access for divers in structures Invite marine contractors to integrate diving in bids Modern DSV s are state-of-the-art construction vessels

16 Conclusion The benefits of using manned underwater operations must be considered in the early phase of subsea projects. In all phases in project planning; Do not define concept or contract strategy in such a way that it s exclude use of manned intervention. Keep the option open for manned operations in the ITT phase to harvest the value. This work can only be done due to good HSE statistics and based on thorough risk management

17 Pål Atle Solheimsnes Leading Advisor Subsea Intervention and Diving