Line pressure stress affects MFL signals

Journal Article · Mon Mar 18 04:00:00 EST 1996 · Oil and Gas Journal

OSTI ID:207888

Hauge, C; Atherton, D L ^[1]

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1. Queen`s Univ., Kingston, Ontario (Canada)

Recent research now indicates the large effects of stresses on magnetic flux leakage (MFL) defect signals can be explained in terms of stress-induced changes in line pipe magnetic properties. The examples shown here are for the previously used axial magnetic field but with circumferential tensile stress, such as generated by line pressure. The different relative alignments of field, applied stress, and magnetic easy axis, which depends on the particular pipe material, cause important differences in the effects of stress on the MFL signal. Understanding these effects is important in evaluating the results of an inspection pig run.

• OSTI ID: 207888
• Journal Information: Oil and Gas Journal, Journal Name: Oil and Gas Journal Journal Issue: 12 Vol. 94; ISSN OIGJAV; ISSN 0030-1388
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
DATA ANALYSIS
FLUXMETERS
LEAK DETECTORS
MAGNETIC TESTING
NATURAL GAS INDUSTRY
PETROLEUM INDUSTRY
PIPELINES
STRESS ANALYSIS