Utvärdering av metoder for feldetektering av planetväxlar för mutterdragare

• Main Authors: Boman, Jon, Storck, Gustav
• Format: Others
• Language: Swedish
• Published: KTH, Maskinkonstruktion (Inst.) 2014
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168907

Atlas Copco utfor accelererade livslangdsprov pa sina planetvaxlar for mutterdragare genom attkora dem med konstant hastighet och konstant moment tills de havererar. Foretaget onskade ettsatt att under drift detektera tidiga fel i vaxeln for att kunna avbryta testerna medan skadorna fortfarande ar i ett tidigt stadium. Syftet med detta examensarbete var att utvardera olikametoder for feldetektering av planetvaxlar.En bakgrundsstudie utfordes for att nna tidigare forskning inom omradet. Sen utfordes testeri en testrigg dar Normalised Summation of Dierence Spectrum (NSDS) och Filtered Root MeanSquare (FRMS), beraknade fran den uppmatta transversal- och torsionsvibrationen, anvandessom indikatorer for vaxelns halsotillstand.Resultaten fran testerna antydde att NSDS och FRMS formaga att indikera tidiga fel i vaxelnvar bristfalliga. Dock sa kunde liknande monster i torsionsvibrationen observeras for de vaxlarsom hade samma typ av skador, dar amplituden i ett sidoband till kuggingreppsfrekvensen okadekraftigt innan vaxeln havererade. === Atlas Copco performs accelerated life testing on their planetary gears for nutrunners by running them at constant speed and torque until they fail. The company desired a way to detect initial gear faults during operation in order to stop the tests while the damages were still in an early stage. The purpose of this thesis was to investigate different methods for planetary gear fault detection. An initial background study was performed to investigate previous research within the field. Then tests were performed in a test rig where the Normalised Summation of Dierence Spectrum (NSDS) and Filtered Root Mean Square (FRMS), calculated from the measured transversal andtorsional vibration, were used as indicators of the gears health state. The results from the tests indicated that the NSDS and FRMS were decient as indicators of initial gear faults. However, similar behaviour in the torsional vibration could be observed for different gears with the same fault mode, where the amplitude in one of the sidebands to the mesh frequency increased signicantly before the gears failed.