• Lionel ROUCOULES, Professor, Arts et Métiers Paris Tech, President
  
• Serge SAMPER, Professor POLYTECH Annecy Chambery, Reviewer
• Jean Pierre NADEAU Professor, Arts et Métiers ParisTech, Reviewer
• Bernard ANSELMETTI, Professor, Université Paris Sud, Supervisor
  

Keywords: Tolerancing, Tolerance synthesis, Thermal expansion, Optimization

Abstract

Functional dimensioning should guarantee assembly feasibility and proper functioning of a mechanism giving functional specifications on parts to be met. Those specifications are defined with ISO standard and may be considered at 20°C. For high heated mechanisms, impacts of tolerances and thermal expansion for all thermal stages have to be combined. After giving behavior assumption into links with clearance or not while considering thermal expansion and uncertainty of temperature, the proposed method makes it possible to separate thermal calculations and tolerancing. Thermal calculations office determines temperature field and displacements from nominal parts by finite elements method. Integration of tolerancing and thermal expansion is based on analysis direction method. For each requirement, final surface is discretized in various points. In every link, transfer relations determine contact points and impact of thermal expansion on these analysis points on the requirement. A study case shows the interest of nominal dimension optimization in order to maximize tolerances while respecting all mechanism requirements.