Lont Term Wear Studies

Diameter loss of individual wheels over time

Long term wear illustrated using one specific pair of wheels

Railroad wheelsets have a limited service life owing to unavoidable wear on the running tread and wheel flange. In direct interaction with the wheels, a rail's head surface is subject to the same kind of damaging mechanisms. Unfavorable profile pairings and stresses may exacerbate those adverse effects. Technical standards on how to monitor profile quality were soon developed for transport safety reasons.

Originally, special gauges were used to manually check rails in exposed locations (such as tight curves). Nowadays, railroad organizations are relying on advanced laser technology to monitor the condition of their networks. Wiener Linien is the only urban transit provider worldwide to boast two measurement cars, one for streetcar and the other for metro (underground) track recording.

Wheel profiles are checked for their geometry in workshops. For this purpose, the former mechanical gauges and templates have been replaced by automated measuring devices. In a long-term test series the wheels of various ultra low floor cars (ULF) were measured, using the mobile MiniProf measuring equipment. The upper figure shows the diameter loss of individual wheels over time, hte bottom figure uses a pair of wheels to illustrate wear behavior.

Wiener Linien has now decided to purchase automated stationary wheel profile measuring equipment. All the measured wear data are being collected in a joint database to meet the requirements of an integrated maintenance system.