GLO Offshore South East Asia Steve Gas Lift Gossell MEA Senior Gas Lift Engineer

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Field Review Compressed Gas on 90% of Platforms Gas Volume not Limited Single String Tubing 3 ½” PPO (Fluid Operated) Valves 1.0” Spring Loaded Operating Orifice Valves made from Unloading Valves Step 1 GLO Project

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GLO Offshore South East Asia Steve Gas Lift Gossell MEA Senior Gas Lift Engineer Field Review Offshore 100 150 meter water depth Stacked Reservoirs ft 7 Cased Hole Depletion Drive small Compartments Some Strong Water Drive Bottoms Up Commingled Reservoirs Sandstone Unconsolidated m ( ft) TVD Field Review Compressed Gas on 90% of Platforms Gas Volume not Limited Single String Tubing 3 PPO (Fluid Operated) Valves 1.0 Spring Loaded Operating Orifice Valves made from Unloading Valves Step 1 GLO Project Objectives Primary: Change PPO to IPO Unloading Valves in 40 wells Increase Oil Production by 10% Teach Process Secondary: Inspect all Valves Pulled Evaluate Gas Lift Design Logic Evaluate Gas Lift Shop & Field Operations/Facilities Process Dedicated GLO Slick Line Unit Flowing Gradient Surveys Before & After Change Valves: Before FGS with Well Test Static Build-up Calibrate Well Model IPR & Match VL Correlation Gas Lift Design & Valve Change After Repeat FGS with Well Test after 3 days for Stabilization Check Model Inspect Valves Report Production Results 24 Wells FGS Examples Compare Before & After Results Compare Pattern of Outflow Performance Note Liquid Rate, Water Cut, & Draw down 66% Increase 146% Increase 520% Increase 143% Increase 811% Increase (Realistically 64% based on Avg. Well Test 250 bpd 96% WC) Example Well Model Strong Water Drive Note Match from Calibrated Model to 2 nd Well Test Load Well Test & Survey Data into Model Not a good match Calibrate Model Good Match: Suspect total gas from separator too high, change GOR Determine Optimum Injection Rate Nodal result from calibrated model Match Inflow/Outflow with Optimum Lift Gas Rate Create Gas Lift Design Design for Worst Case Scenario 2nd Survey, New Design, Check Model 43% Measured Increase in Liquid Rate Valve Inspection Results 84 PPO Valves Inspected from 27 Wells 65% with Test Rack Open (Ptro) Set Pressure 10% or more out of Design Range. 26% with Failed Bellows; would not open. 46% with Leak Rates medium to very high. 14% with Leak Rates so high could not measure Ptro. 11% tested OK = only 1 in 9 valves passed inspection. 25 Orifices Inspected: 52% with failed bellows restricting flow. Offshore Gas Lift Shop Facility Ptro set with Hydraulic Oil Pump Packing Filed Down to Assist Installation 4082 #3 2967 #2 1851 #1 PPO as Orifice Valve: Remove Ball Bellows failed & extended into Flow Path on 13 of 25 Orifices inspected = 52%. PPO as Orifice Valve: Bellows extended onto seat SCSSSV: Full Bore Flapper vs. Ball Valve Thanks for Listening Questions or Comments? Steve Gas Lift Gossell MEA Senior Gas Lift Engineer