Business Benefits Delivered through True Valve Performance

1. Business Benefits Delivered through True Valve Performance Yvonne Roberts Edinburgh Petroleum Services 1

2. Introduction $$ i-AM Total System Optimisation Well Modelling True Valve Performance 2

3. intelligent Asset Management • intelligent Asset Management is maximising the value that an oil or gas field delivers over its life from discovery to abandonment. • Initial investment (optimise strategy for production) • Daily Operations (optimise investments already made) • Planning (optimise timing and amount of future investments) • For any producing asset, the first element is complete and the major emphasis is on intelligent Operation and Planning. 3

4. Qprod @ THP • Valve Data custom-measured by Valve Performance Clearinghouse • Measured data, not generic correlations • Data specific to valve type and port size • Accuracy! Qgi @CHP TVP Qgi Thornhill-Craver/orifice Gas-charged valve IPR Pdown True Valve Performance (TVP) 4

5. On-line integration with SCADA systems Off-line activities Gas-Lift and Total System Optimisation Steady-state Tuning and Analysis Dynamic Gas-Lift Analysis Well Model Tuning Gas-Lift Diagnosis Data Flow Well Models with TVP 5

6. Other uses= Qgf-Qgc Compressors +$ Pdisch ProducedGas= Qgf+Qgi Fuel, Qgc Lift Gas,Qgi -$ Surge Stonewall Qsuction TVP provides the link Qoil Oil + Water +$ -$ Gas-lifted Wells (Curves for one THP) CHP FormationGas, Qgf Gas Injection Rate Total System Optimisation 6

7. Valve performance curve for a given CHP PT @valve Increasing CHP (and PC @valve) Unstable operating point Tubing Performance for a given THP Limit of valve stability Amount of gas injected by that valve at the given Casing and Tubing pressures Minimum stable gas injection rate Qgi Valve Stability 7

8. Produced Fluids from Production Manifold Flow Group 3 Wells Flow Group 2 Wells Flow Group To other Flow Groups To other Flow Groups Gas Injection Manifold (Pm2, Tm2) Gas Injection Manifold (Pm1, Tm1) ReO Optimisation Multiphase Optimisation 8

9. Check Gas Supply Status Calculate deepest possible point of injection Check Production Status Check which valve(s) open and the opening margin(s) PCas Mandrel 1 PTub Mandrel 2 Depth Check complete pressure drop from CHP to THP using valve models Mandrel 3 Mandrel 4 Advise operator and recommend remedial action if necessary Pressure On-line Diagnosis (Sedilag) Read SCADA Surface Production Data 9

10. Qgi(t) Inflow Dynalift 10

11. Benefits through Optimisation • Venezuela/Maracaibo • automated optimisation and GL-diagnosis • 250 wells leading to gains worth around $36 Million/annum • Kuwait • automated optimisation and performance analysis • >400 wells with projected impact of $100-175 Million/annum • Norway/Ekofisk • impact assessment of Ekofisk II/integration with SCADA • sustain increased production worth ~ $180 Million/annum • North Sea • analysis and optimisation of single well performance • prevention of over-intervention yielded production increase of ~ $1000/d. 11

12. Business Benefits Delivered through True Valve Performance Yvonne Roberts Edinburgh Petroleum Services 12