Electromagnetic methods for inspection of ferrous tubing

Conference · Wed Apr 24 04:00:00 EDT 1974

OSTI ID:6853977

Crowe, J. C.

Electromagnetic-acoustic (EMAC) techniques have been applied to the nondestructive inspection of ferromagnetic tubing. EMAC combines the advantages of noncontract electromagnetic inspection with the flaw detection capabilities of ultrasonic inspection techniques. Laboratory studies have demonstrated the capabilities of the method for detecting cracks, pits, and wall thinning in carbon steel boiler tubing. Results of the studies demonstrate the feasibility of using internal EMAC probes for inspection of installed tubing. Multiparameter eddy current techniques show promise for detecting wall thinning in ferromagnetic tubing. A two frequency multiparameter eddy current system was shown to provide the parameter separation capability necessary for the detection of wall thinning in the presence of shallow internal pitting and surface scale. Machined steps in the wall of carbon steel tubing were detected with the multiparameter system. An internal magnetization probe was applied to ferromagnetic tubing. The internal magnetization probe concept may be used to produce increased penetration of eddy current signals, to reduce magnetic permeability variations in ferrous tubing, and can be incorporated into EMAC inspection probes. Further development of one or more of these electromagnetic inspection techniques may provide a means for field inspection of installed ferrous tubing.

• Research Organization: Battelle Pacific Northwest Labs., Richland, Wash. (USA)
• DOE Contract Number: EY-76-C-06-1830
• OSTI ID: 6853977
• Report Number(s): BN-SA-311; CONF-741074-2
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420500* -- Engineering-- Materials Testing
ALLOYS
BOILERS
ELECTROMAGNETIC TESTING
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS TESTING
NONDESTRUCTIVE TESTING
STEELS
TECHNOLOGY ASSESSMENT
TESTING
TUBES