Paper: The Application of Pressure and Temperature Surveys to Gas Lift Installations

The purpose of this paper is to illustrate the application of pressure and temperature surveys to gas lift installations, not to discuss the mechanics of bottom hole pressure and temperature instruments. The advantages of pressure surveys prior to the installation of gas lift equipment are discussed. The procedure for running surveys in intermitting gas lift wells is offered. The determination of the operating valve or valves, using both the temperature and pressure survey in the same well, is presented. Examples of surveys in a gas lift well with a tubing leak and a well with leaky valves are given. Bottom hole pressure surveys for chamber installations are noted which show the minimum flowing bottom hole pressures obtained with low pressure versus high pressure operating gas lift valves. The paper concludes by illustrating the use of a pressure survey for estimating per cent fallback in an intermitting gas lift installation.