Development of compound inspection system for wirerope.

Research Project

Project/Area Number	05650955
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	資源開発工学
Research Institution	KYOTO UNIVERSITY
Principal Investigator	HANASAKI Koichi KYOTO UNIV., FAC.ENG., PROFESSOR, 工学部, 教授 (20026123)
Co-Investigator(Kenkyū-buntansha)	TSUKADA K KYOTO UNIV., FAC.ENG., LECTURER, 工学部, 講師 (10179971)
Project Period (FY)	1993 – 1994
Project Status	Completed (Fiscal Year 1994)
Budget Amount *help	¥2,200,000 (Direct Cost: ¥2,200,000) Fiscal Year 1994: ¥800,000 (Direct Cost: ¥800,000) Fiscal Year 1993: ¥1,400,000 (Direct Cost: ¥1,400,000)
Keywords	WIRE ROPE / NONDESTRUCTIVE TESTING / MAGNETIC FLUX LEAKAGE METHOD / MAGNETIC DIPOLE / INVERSION PROBLEM / 非破壊検査
Research Abstract	The safety and lifespan of wire rope utilized in rope ways, cable cars of lifting machine of mine, and in suspension roofing structures as tension member, are determined by the damage degree and strength of the wire ropes used. It is therefore desired to establish a method that allows accurate assessment of damage that takes place inside the wire ropes due to fatigue or corrosion. To clarify the mechanism for damage within wire ropes and to explore methods for the prevention of such damage, it is essential to accurately assess the site of damage within the cross-section of wire ropes. Using the data of magnetic flux leakage obtained from multiple points around a damaged wire rope, during saturation magnetiza tion in the longitudinal direction of the rope, an attempt has been made to prepare tomograms, which are based on the degree of damage at each point inside the rope that was obtained as the solution to an inverse problem which was solved by using a modified least square method with a restriction that the magnetic charge must not be negative. The results agree considerably with the location of de fects in the rope. Examining the influence of the direction of the magnetic flux leakage measurement on the solution obtained, it is recom-mended to use z and theta directions.