Title
A Lift-Off-Tolerant Magnetic Flux Leakage Testing Method for Drill Pipes at Wellhead.
Abstract
To meet the great needs for MFL (magnetic flux leakage) inspection of drill pipes at wellheads, a lift-off-tolerant MFL testing method is proposed and investigated in this paper. Firstly, a Helmholtz coil magnetization method and the whole MFL testing scheme are proposed. Then, based on the magnetic field focusing effect of ferrite cores, a lift-off-tolerant MFL sensor is developed and tested. It shows high sensitivity at a lift-off distance of 5.0 mm. Further, the follow-up high repeatability MFL probing system is designed and manufactured, which was embedded with the developed sensors. It can track the swing movement of drill pipes and allow the pipe ends to pass smoothly. Finally, the developed system is employed in a drilling field for drill pipe inspection. Test results show that the proposed method can fulfill the requirements for drill pipe inspection at wellheads, which is of great importance in drill pipe safety.
Year
DOI
Venue
2017
10.3390/s17010201
SENSORS
Keywords
Field
DocType
MFL (magnetic flux leakage),drill pipe,lift-off distance,magnetic field focusing
Geotechnical engineering,Wellhead,Lift (force),Magnetic flux leakage,Ferrite core,Electronic engineering,Drill pipe,Engineering,Helmholtz coil,Drill,Drilling,Marine engineering
Journal
Volume
Issue
Citations 
17
1.0
1
PageRank 
References 
Authors
0.49
0
8
Name
Order
Citations
PageRank
Jianbo Wu124.24
Hui Fang210.49
Long Li310.49
Jie Wang410.83
Xiaoming Huang521.20
Yihua Kang643.66
Yanhua Sun710.49
Chaoqing Tang820.86