Modelling Cutting States in Rough Turning of 34CrNiMo6 Steel
Ratava, Juho (2015-06-05)
Väitöskirja
Ratava, Juho
05.06.2015
Lappeenranta University of Technology
Acta Universitatis Lappeenrantaensis
Julkaisun pysyvä osoite on
https://urn.fi/URN:ISBN:978-952-265-801-2
https://urn.fi/URN:ISBN:978-952-265-801-2
Tiivistelmä
Rough turning is an important form of manufacturing cylinder-symmetric parts. Thus far,
increasing the level of automation in rough turning has included process monitoring methods
or adaptive turning control methods that aim to keep the process conditions constant. However,
in order to improve process safety, quality and efficiency, an adaptive turning control should
be transformed into an intelligent machining system optimizing cutting values to match process
conditions or to actively seek to improve process conditions.
In this study, primary and secondary chatter and chip formation are studied to understand how
to measure the effect of these phenomena to the process conditions and how to avoid undesired
cutting conditions. The concept of cutting state is used to address the combination of these
phenomena and the current use of the power capacity of the lathe. The measures to the
phenomena are not developed based on physical measures, but instead, the severity of the
measures is modelled against expert opinion.
Based on the concept of cutting state, an expert system style fuzzy control system capable of
optimizing the cutting process was created. Important aspects of the system include the
capability to adapt to several cutting phenomena appearing at once, even if the said phenomena
would potentially require conflicting control action.
increasing the level of automation in rough turning has included process monitoring methods
or adaptive turning control methods that aim to keep the process conditions constant. However,
in order to improve process safety, quality and efficiency, an adaptive turning control should
be transformed into an intelligent machining system optimizing cutting values to match process
conditions or to actively seek to improve process conditions.
In this study, primary and secondary chatter and chip formation are studied to understand how
to measure the effect of these phenomena to the process conditions and how to avoid undesired
cutting conditions. The concept of cutting state is used to address the combination of these
phenomena and the current use of the power capacity of the lathe. The measures to the
phenomena are not developed based on physical measures, but instead, the severity of the
measures is modelled against expert opinion.
Based on the concept of cutting state, an expert system style fuzzy control system capable of
optimizing the cutting process was created. Important aspects of the system include the
capability to adapt to several cutting phenomena appearing at once, even if the said phenomena
would potentially require conflicting control action.
Kokoelmat
- Väitöskirjat [1037]