All published continuous-flow gas-lfit installation designs not unload

摘要

All published continuous-flow gas-lift installation designs will no unload to a maximum depth of lift on te basis of the avaiable injection-gas pressure becase of unloadig gas-lift valve interference. Gas-lift valve performance should be considered in the test-rack set opening proessure calculation and port size selection. The unloading injection-gas requiement and the necessary pressure increase for stroling a valve stem with the same port size increase for each deeper unloading valve depth. An understanding of the performance of the type of gas-lfit valve in a well is necessary to properly design a continuous-flow installation and analyze its gas-lfit operation. The single-element, unbalanced, nitrogen-charged bellows, injection-pressure-operated type of gas lift valve is used to gas-lift most installations worldwide. The continuous-flow installation design that is discussed in this paper utilizes this type of gas-lfit valve and a constant surface operating injection-gas pressure.