Since hydrostatically guided machine parts float on a film of oil, the frictional force is low and proportional to the speed. This also applies to extreme loads. The frictional force is therefore also zero when the direction of motion is reversed – at zero speed and close to zero – path errors, for example when driving a circle using a hydrostatic cross slide, are avoided. The path fidelity of a movement is maintained to a high degree even when the direction of movement of a carriage is reversed

– Stick-slip is reliably avoided even under high loads

– Carriage drives are practically only to be designed for sufficient accelerations and machining forces and therefore smaller and more cost-effective to define due to the negligible friction force

– The vibration damping of hydrostatic components is usually at least several times higher than that of rolling elements.

This becomes understandable when one knows that the damping force at higher excitation frequencies is proportional to the viscosity and the third power of the web width and inversely proportional to the third power of the gap height. The damping force can therefore be optimized to a very high degree by optimally selecting the web widths and gap sizes in particular.

– High damping and better damping absorption performance, result in longer tool life, better surface qualities on the workpiece and higher marginal metal removal rates, as regenerative chatter is largely avoided.

– Due to the integrating effect of hydrostatics, errors of guideways that are shorter than the hydrostatic pockets are almost completely eliminated.

– Radial and axial running errors smaller than 0.1 µm are possible over the entire speed range, even at high speeds. Concentricity errors of 30 nm have already been delivered.

– The running qualities remain unchanged over the entire service life due to the absence of wear.

– The hydrostatic fluid can, for example, be cooled back to a few °C below the machine temperature, whereby the temperature of the fluid deviates only minimally from the machine temperature due to pressure reduction in the hydrostatic pockets. As a result, heat input into the machine is almost completely avoided by the hydrostatic system. This can even compensate for the heat input from other machine components.

– This is also possible with very high-speed spindle bearings.

– As a result, only a very small amount of heat is generated by the machine. If cooling is not activated until the steady-state temperature of the fluid is reached, the already short warm-up phase is again greatly reduced.

– By measuring the pocket pressures, it is possible to monitor the machine and the load limits, and also, for example, to monitor the tool wear.

– In cylindrical radial bearings, a shaft can rotate and be displaced longitudinally. This is of great advantage for rotating quills, e.g. for rotating tailstock quills