Finite Element Analysis of Engine Bore Distortions During Boring Operation

Bore geometry is the major factor affecting oil comsumption, piston ring wear, and frictional losses in an engine. As such, auto industries have been constantly striving to develop better machining technologies to produce engine bores with greater precision. Experimental studies have shown that the bore distortion as a result of machining is mainly caused by temperatures and stresses created during cutting. Consequently, optimization of machining conditions so as to minimize both bore temperature gradients as well as mechanical stresses while machining should lead to the production of better bore geometry. This research develops a model aimed at simulating bore distortions caused by temperature changes and stresses generated during machining using finite element technique. The commercial finite element package ANSYS has been used along with the CAD package I-DEAS to simulate the boring process on DEC-VAX computers. The simulation procedure developed can be used to obtain a better understanding of the boring process, in particular, to determine distortion trends for different cutting conditions.