公开(公告)号：US20210301643A1

公开(公告)日：2021-09-30

申请号：US17202584

申请日：2021-03-16

Applicant: CNPC Engineering Technology R&D Company Limited

Inventor： Guodong JI ,  Haige WANG ,  Meng CUI ,  Zhao MENG ,  Qiang WU ,  Li LIU ,  Jiawei ZHANG ,  Changchang CHEN ,  Liu CUI ,  Jing YU

IPC: E21B45/00 ,  E21B12/02 ,  E21B10/567 ,  E21B49/00

Abstract: A method for evaluating a downhole working condition of a PDC bit includes: performing an indoor test, including performing a drilling test in different full-sized cores by using the PDC bit with different degrees of abrasion and balling under condition of given WOB and rotational speed, to acquire change characteristics of a WOB, a rotational speed, a torque, a ROP and a bit vibration of the PDC bit in different time domains; improving and perfecting an existing prediction model and evaluation method for the downhole working condition through data obtained by the test to obtain the method; reading parameters of the WOB, the rotational speed, the torque and the ROP in real time during drilling; determining the downhole working condition of the PDC bit by using the method in the improving and perfecting.