Continuous Gas-Lift Instability: Diagnosis, Criteria, and Solutions

Abstract

Abstract This paper presents field data that show how continuous gas lift instability is manifested. It also reviews former proposed criteria to predict the phenomenon. The best available criteria are selected and expanded to take into account different flow regimes for the surface gas injection valve and the bottomhole gas-lift valve. The expanded criteria are examined using field data. The criteria clearly show the relative importance of the different factors involved, and thereby help to assure stable flow conditions at the design phase or to decide what actions to take in order to stabilize an unstable gas lift well.