How Drawbar Monitoring Saves You from Loss Productivity and Downtime

By: Harold Goellner, OTT-JAKOB Drawbar Specialist

When it comes to machine tools, the spindle is the engine that drives the power to the cutting tool, and the drawbar is at the heart of the entire spindle’s operation. One problem in the drawbar can cause other types of failure that result in loss of productivity and unscheduled downtime. Consistent drawbar monitoring ensures optimal spindle performance that is less costly than the damage that comes from neglecting it, including:

1. Taper spindle regrind
2. Macine downtime
3. Fretting and bell mouthing of the taper
4. Repeatability problems
5. Degradation of tool life or surface finish

There are several monitoring assistance systems available for early detection of drawbar deficiencies, including:

1. An MSU multi-sensor unit that combines a distance measurement system to sense unclamped, tool clamped (clamped with tool), and clamped without tool positions of the drawbar; and an unclamped piston position monitor (KAS).
2. A telemetry monitoring system that monitors the pull force of the springs.
3. A condition monitoring system that monitors the leakage drainage flow of the hydraulics and coolant in a rotary union.

Incorporating drawbar monitoring with your preventative maintenance schedule allows you to identify and repair drawbar deficiencies before complete system failure begin.