The application of adaptive hydrostatic bearings in heavy lathes
This article provides an analytical review of methods for improving the machining accuracy of heavy lathes, various options for bearing of the spindle assemblies. It is the bearing assemblies that make the decisive contribution to the machining accuracy. The application of rolling-contact bearing has a certain accuracy limit, since the sources of displacement for a given trajectory of movement are the geometric surfaces of the tracks and rolling elements, changes in the force distribution in the bearing due to changes in the position of the rolling elements relative to the line of external load action, and the presence of deformations, like the rolling elements themselves, and the interfacing surfaces. The main part of the article presents a combined hydraulic circuit of a spindle unit with hydrostatic bearings, which combines electrical control with hydraulic executing mechanisms. The principle of operation of such a system is described and its structural diagram is given.