Patent ID: 8684108
Filing Date: 2014-04-01
Classification: E21B,G01H,G01V,G05B,G06F

Abstract:
1. A method of monitoring the operation of a drill string drilling into an earthen formation so as to form a bore hole using a drill bit located in a bottom hole assembly, comprising the steps of: determining the values of a plurality of operating parameters associated with said underground drilling operation, the values of the plurality of operating parameters obtained from a plurality of sensors during the drilling operation, at least a portion of said sensors located in said bottom hole assembly, the plurality of operating parameters including at least a vibration of the drill string; determining from the determined values of the plurality of operating parameters whether at least one of a plurality of predetermined symptoms of lost drilling performance is present in said drilling operation; identifying the probability that each of the predetermined symptoms of lost drilling performance determined to be present in said drilling operation are caused by each of a plurality of predetermined causes of lost drilling performance; and combining said identified probabilities for each of the respective plurality of predetermined causes of lost drilling performance for each respective predetermined symptom of lost drilling performance determined to be present in the drilling operation, wherein the greatest combined probabilities among the respective plurality of predetermined causes of lost drilling performance is the most likely cause of lost drilling performance present in said drilling operation.