DOI: 10.14489/td.2016.12.pp.010-015

Tsvaigert R. G., Stepanova L. N., Kabanov S. I., Chernova V. V.
RISK LEVEL DETERMINATION OF A DEFECT OF FREIGHT-CAR TRUCK SOLEBAR USING ACOUSTIC EMISSION TECHNIQUE
(pp. 10-15)

Abstract. The freight-car truck solebars sustain both vertical and horizontal cyclic load on-stream. The manufacturing casting defect (abscesses, holes etc.) can lead to quick breaks and accidents. Final inspection of cast parts by active methods of nondestructive test (NDT) (visual, magnetic, fluxgate methods, eddy current testing) is not always effective because of the roughened surface and scales. In addition, the part of the most critical defects is possible to detect only in the load carrying object. An acoustic emission technique (AE) is used for before-the-fact propagate defects identification and assessment their risk level in real-time. It is suggested to perform calculations of localized defects risk level with usage of integral danger coefficient during the strength tests of freight-car truck solebars. The integral danger coefficient is caused by informative parameters (amplitude, MARSE, rise time of riseup portion envelope, dominant frequency, two-interval coefficient) of AE signals. It is analyzed the dependence of distance from the fracture zone to the nearest acoustic sensor, to the informative parameters. It is indicated that values of amplitude, MARSE and two-interval coefficient increased when distance, from the fracture zone to the sensor, increased too. Taking into account the informative parameters distance relations improves the reliability of estimating the risk level of defects and the quality of the rejection. The example of determination of risk level for two defects located in the solebars are given.

Keywords: cast, defect, solebar, danger coefficient, acoustic emission.