RailMeasurement’s TriTops measures irregularities on a railway wheel. TriTops can be taken to site in a handy plastic instrument case and used by one person. It was developed for a major vehicle supplier and is used by them.
Measurements are taken, as with most other equipment for this purpose, by jacking a wheelset off the ground and rotating the wheel by hand while measurements are recorded by the instrument. Typically about 4 wheels can be measured in an hour with two people (one jacks up and turns the wheelset, the other moves the equipment under the train and takes the measurements). Measurements are given at three positions across the wheel tread and at a location from flange-back that can be readily adjusted.
The TriTops software gives the following measurements and shows the following features:
- Displacement, corrugation, out-of-round, diameter
- acoustic roughness and one-third octave spectra (according to EN15610)
The software can produce this information immediately after a measurement has been taken. It is thereby possible for the operator to check the condition of wheels as measurements are made.