Analysis of the Room Temperature Fitting Process for Assembling the Part(Valve Seat and Cylinder Head)

Valve Seat/Cylinder Head 단품조립을 위한 상온압입공정 해석

  • 배준호 (부산대학교 기계공학부) ;
  • 김문생 (부산대학교 기계공학부) ;
  • 우타관 (부산대학교 기계공학부) ;
  • 김태진 (현대자동차 파워트레인 생기센터) ;
  • 오준동 (현대자동차 파워트레인 생기센터) ;
  • 김철 (부산대학교 기계기술연구원)
  • Published : 2009.12.01


There are three sub-processes associated with the assembly of the valve seat and cylinder head; heat fitting, cold fitting, and shrink fitting. In the heat fitting stage, the cylinder head is heated to a specified temperature and then squeezed toward the outer diameter of the valve seat. The cold fitting process cools the valve seat and safely squeezes it toward the inner diameter of cylinder head. However, these methods increased the installations & running cost and curtailed productivity. To address these problems, we analyzed the shrink fitting process using the contact pressure caused by fitting interference between the outer diameter of the valve seat and the inner diameter of the cylinder head. In this study, a closed form equation for predicting the contact pressure and fitting load is proposed. For quality control of the assembly line, principal factors of the shrink fitting process influenced in contact pressure were simulated by the FEM. Actual loads measured in the field showed good agreement with the results obtained by theoretical and finite element analysis.


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