NEW APPROACH FOR THE CRANKSHAFTS GRINDING AND DETERMINATION OF THE 3D SURFACE ROUGHNESS MODEL FOR THE CRANKSHAFTS BEARINGS

摘要

The novel technological equipment for diesel engines crankshaft bearing surfaces (journals) grinding has been elaborated. This technology is generally applicable to the medium size shipboard diesel engines with crankshaft journal diameter from 100 up to 350 mm. This innovation allows repairs of the crankshaft to be carried out directly in the engine housing, without removing it from the engine, and, in addition, making unnecessary to dismount the whole engine. Furthermore, when the above mentioned technology was certified for grinding of the crankshaft journals, the geometrical form and surface roughness of bearings fully complied with the established technical requirements. Thus novel technology provided the efficient solution for crankshaft bearing machining problems which allow significantly decrease maintenance time of ship engines and to save considerable financial resources. Accordingly the new three-dimensional surface roughness model, and its microtopographical surface roughness parameters, which are suitable for diesel engine crankshafts bearing surfaces were developed as well. It has been determinate, that the optimal microtopographical model of the particular surface is composed by the following parameters: roughness height parameter R_(aT) and two spacing parameters S_(m1) and S_(m2). The measurement basis for these roughness parameters is a mean plane of overall roughness.