METHOD AND SYSTEM FOR MEASURING AND CALCULATING A MODIFIED EQUIVALENT CIRCULATING DENSITY (ECDM) IN DRILLING OPERATIONS

摘要

A method for collecting and analyzing downhole pressure data includes disposing a plurality of pressure sensors at axially spaced locations along a drill string disposed in a well. A first data set that includes a data point for each of the pressure sensors is collected. Each data point includes a pressure value and a depth value. A value of modified equivalent circulating density (ECDm) is calculated for at least one data point. ECDm includes a static pressure component and a dynamic pressure component. Calculating the ECDm includes computing the static pressure component based on the true vertical depth of the pressure sensor, and computing the dynamic pressure component based on a second depth value that differs from the true vertical depth and is common to all the pressure sensors for which ECDm is calculated.