Express-Method of Forecasting The Maximum Annular Pressure in Mechanized Production Wells During Pressure Transient Analysis

Abstract At the present time one of the most common methods of well testing is pressure build-up test at the shut-in of production well. When the well is closed for research the process of bottomhole pressure (BHP) increase is accompanied by a change in the dynamic head and increasing the gas pressure at annular space (Shagiev, 1998). Growth of casing pressure above limit pressure can lead to technical problems at wellhead. This paper describes a method for predict the pressure in the annular space and the dynamic head in the end of the pressure transient test and bottomhole pressure build-up to the current reservoir pressure. Express-method of forecasting of casing pressure is tested on experimental examples of research in mechanized wells. In most cases, calculated casing pressure value corresponds with the measured data (successful prediction by this method is 70%). In most cases, forecasting method of casing pressure recovery for vertical mechanized wells allows to determine the possible excess casing pressure above the critical pressure at the wellhead (for example, a possible increase above of test pressure and limit pressure which can connect with some gaps at the wellhead) pressure build-up test. Presented express-method of forecasting can be used in the selection of wells-candidate for well testing, at prevention and reduction of potential problems and for discontinuation well testing due to high casing pressure, improving the success of well testing.