Continuous-flow gas-lift installation design utilizing production pressure-operated valve performance

摘要

The vorioble-gradient design-line method is a widely accepted procedure for spacing gas-lift valves (GLV's) in a continuous-flow gas-lift (GL) installation. Injection-pressure-operated (IPO) and production-pressure-operated (PPO) GLV's can be used in a variable gradient designed installation. The primary purpose of GLV's is to unload a well to the desired depth of gas injection. If the installation design is based on a constant surface injection-gas pressure (P_io), the GLV's must be opened by an increase in the flowing-production pressure at valve depth (P_pfd) rather than an increase in injection-gas pressure at valve depth (P_ioD). PPO, also called fluid-operated, valves are opened and closed by changes in P_pfD.