Electricity: measuring and testing – Magnetic – With means to create magnetic field to test material
Patent
1994-11-28
1997-03-25
Snow, Walter E.
Electricity: measuring and testing
Magnetic
With means to create magnetic field to test material
324235, 324262, G01R 3312, G01N 2772
Patent
active
056148259
ABSTRACT:
Magnetic flux leakage inspection apparatus systems with independently suspended magnetic sensor blocks. The apparatus includes a magnet and a sensor assembly. The magnet is disposed over a surface of a magnetizable material under inspection for inducing magnetic flux in the material, and the sensor assembly is disposed in a predetermined inspection position over the surface for detecting magnetic flux leakage from the material that may indicate a magnetic anomaly in the material. The magnet and sensor assembly are moved along over the surface while the sensor assembly scans for magnetic leakage flux. The sensor assembly is formed with one or more independently suspended sensor blocks, each block including a plurality of sensors rigidly held in the block for detecting magnetic flux leakage. Each sensor block is independently mounted to permit the block to move perpendicular to the surface under inspection during the course of measurement as the sensor assembly and the surface are moved in scanning relation to one another. To avoid contamination of the measurement results by the normally present parallel flux leakage components, each block is subject to stringent constraints on the permitted departures of the perpendicular movement from perpendicularity, that is, on the amount by which the block may tilt as it undergoes its perpendicular movement. Each of the one or more blocks may be disposed to ride on the surface of the material under inspection, and each block may then undergo perpendicular movement independent of any other block in response to variations of the surface encountered in the course of inspection without causing undesirable magnetic field measurements to be mixed into the detected signal that would otherwise mask the much weaker desired signal indicative of magnetic anomalies.
REFERENCES:
patent: 2313729 (1943-03-01), Barnes
patent: 4041379 (1977-08-01), Karlsson
patent: 4258319 (1981-03-01), Shimada et al.
patent: 4510447 (1985-04-01), Moyer
patent: 4704580 (1987-11-01), Moake et al.
patent: 4710712 (1987-12-01), Bradfield et al.
patent: 4814705 (1989-03-01), Saunderson
patent: 5279160 (1994-01-01), Koch
Wiegant, "Automated NDT of Storage Tank Bottoms," Contribution to the KINT-BANT Symposium, Sep. 8-9, 1988, Antwerp, Belgium.
Nestleroth, "A Review of Magnetic Flux Leakage Technology for the In-Line Inspection of Gas Transmission Lines," International Conference on Pipeline Reliability, Jun. 2-5, 1992, Calgary, Alberta, Canada, pp. IV-5-1 to IV-5-12.
Dobmann, "Magnetic Leakage Flux Techniques in NDT, A State-of-the-Art Survey of the Capabilities for Defect Detection and Sizing," in Electromagnetic Methods of NDT, W. Lord, ed., Gordon and Breach, 1985, pp. 71-95.
Stanley, "An Overview of the Latest Magnetic NDE Methods," prior to Nov. 1994.
Fitzgerald Pamela C.
Maxfield Bruce W.
Aronson Elliot B.
Industrial Sensors and Actuators
Snow Walter E.
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