Continuous measurement of drilling fluid rheological characteristics involves using adapted sensor on circulation pipe, to determine rheogram

摘要

Complex dynamic viscosity is measured using an adapted sensor on a circulation pipe. The rheogram of the fluid is deduced, from the law of variation of viscosity as a function of shear. At least one characteristic parameter of the fluid rheology is calculated, starting from the rheogram. This process is repeated after a given interval. Changes in the parameter and in characteristics of the fluid are deduced. Complex dynamic viscosity is measured using an adapted sensor (6) placed on a circulation pipe (5). This obtains the law of variation of complex viscosity eta' as a function of 2pif, where f is the excitation frequency of the sensor. The rheogram of the fluid is deduced, from the law of variation of viscosity eta as a function of shear (gamma'). At least one characteristic parameter of the fluid rheology is calculated, starting from the rheogram. This process is repeated after a given interval. Changes in the parameter and in characteristics of the fluid are deduced. An Independent claim is included for the corresponding system which includes the sensor as indicated, means of calculation and a recording system for the change in fluid characteristics with time.