Wear Rope Flaws And Magnetic Chracteristics

A wire rope subjected to repetitive mechanical loading stresses such as pulling, bending, twisting, wearing and etc. will deteriorate through their entire service life. Deformation, degradation, abrasion and stress concentration will appear in some sections. This deterioration process will destroy the original continuity and uniformity of the load-bearing materials of the rope, resulting in variation of the magnetic energy density of cross-sectional elements, as shown by Fig. 6.
  The deterioration modes of cross-sectional elements of the wire rope could be categorized as LMA defects (elastic rope diameter shrinkage, abrasion and corrosion) and LF defects (broken wires caused by fatigue, plastic wear, martensitic embrittlement or mechanical damage ). When passing through these deteriorated cross-sectional elements of the wire rope, the magnetic lines of force will be distributed along those irregular paths with lower magnetic resistance. As a result, the magnetic flux density and the distribution of magnetic energy products change accordingly. Differences of magnetic energy potentials are thereby produced. Also, the more deteriorated the wire rope, the more different the magnetic energy potentials.
  If a normal or standard cross-sectional element of the test wire rope could be chosen and its magnetic energy potential could be correctly defined, then a benchmark value is available for inspecting the wire rope. By comparing the extracted magnetic energy potential information of all tested cross-sectional elements with the benchmark value, the variation of magnetic energy potentials along the axial direction becomes clear. This variation of the magnetic field reflects the mechanical changes of the load-bearing ferromagnetic materials. With over 20 years R &D efforts, TCK has discovered the correlation between these two variables, which enables the quantitative, qualitative and positioning detecting of all modes of deterioration of the in-service wire ropes.
tckchinamartin tckchinamartin
26-30, M
Sep 6, 2012