公开(公告)号：US10053971B2

公开(公告)日：2018-08-21

申请号：US14853229

申请日：2015-09-14

Applicant: Pason Systems Corp.

Inventor： Stephen William Lai ,  Christopher Darren Salvador ,  Kenneth Charles Horovatin ,  Timothy Keith Walter

IPC: E21B44/00 ,  E21B47/00 ,  G01L5/26 ,  E21B45/00 ,  G01L3/10 ,  G01L3/14 ,  G01L5/12

CPC classification number: E21B44/00 ,  E21B45/00 ,  E21B47/0006 ,  G01L3/108 ,  G01L3/1457 ,  G01L5/12

Abstract: A method for detecting stick-slip in a drillstring includes (a) measuring a parameter that is a function of a torque applied to the drillstring by a top drive system over a selected time period, the measuring being performed by at least one surface sensor that produces measurement data including torque values over a frequency range; (b) filtering out measurement data that has a frequency outside a selected frequency band, the selected frequency band including a resonant frequency of the drillstring; (c) identifying a minimum and a maximum torque value in the filtered measurement data and determining a difference of these two values; (d) determining a surface stick-slip index by dividing the difference of the maximum and minimum torque values by an average torque value over the selected time period; and (e) displaying the surface stick-slip index on a display.