Measurement of Cylinder Bore Deformation During Actual Operating Engines

Abstract

<div class="htmlview paragraph">One of the phenomena accompanying the lightweight/compact/high power output feature of engines is the cylinder bore deformation, which may readily cause increased oil consumption, gas leakage, unusual wear, scuffing, etc.. The authors have had experiences that piston rings had generated contact failure during engine operation (<span class="xref">1</span>)<span class="xref">*</span>. Such deformation is generated as a combination of the static deformation due to head bolt tightening, crankshaft installation, etc., and the deformation by the operating factors; thermal load and combustion pressure. Countermeasure of design have been made for the former (<span class="xref">2</span>)<span class="xref">*</span>, and prediction of the deformation during actual operating have been tried using FEM analysis, etc. for the latter (<span class="xref">3</span>)<span class="xref">*</span>. Therefore, the accurate measurement result have been required strongly, for a long time. But it could not be realized in the past.</div> <div class="htmlview paragraph">In this study, the unique and special method has been developed in order to measure the whole cylinder bore shape directly from a piston ring land under the operation upto high-speed and high-load.</div>