ASME Gas Lift Workshop Spring 2004

1. ASME Gas Lift Workshop Spring 2004 Dual Gas Lift Breakout Session February 10, 2004

2. Problems Successes Gas Lift Design Dual Gas Lift

3. Surveillance Upper / Lower string communication Wire line work more risky on dual wells Interference between strings – gas robbing Need more detailed accurate information for better design Heading problems – fluctuating casing pressure – general instability Generally restricted to using 1” valves. Dual Gas Lift Problems

4. Use of PPO unloading valves on both strings – operate best string on an orifice and the other on an IPO valve. Use of venturi valve Use of shear orifice valve – enables packer test and ability to later to kick-off flowing well if needed. Minimize back pressure, maximize gas lift injection pressure Maximize design effectiveness with good data to start with Properly trained well operators – troubleshooting – need written procedures for testing/optimizing wells Willingness of the Operator to spend the money and time to get measured data (accurate meters, flowing surveys, etc.) Improved monitoring and control via automation/SCADA. Dual Gas Lift Successes

5. Design each string independently of the other. Use PPO mandrel spacing to ensure close mandrel spacing in both strings – don’t “skimp” on mandrels. A re-design of valve placement and set pressures may be required after well is unloaded and well performance is better understood. Verify design performance after well is stabilized – Use the tools: 2 pen or multi-pen pressure recorder Flowing pressure/temp surveys with coinciding well test Evaluate the well test, design and flowing survey data Do not oversize valve port sizes Use dynamic valve flow testing data if available. Dual Gas Lift Design