Condition-based preventive maintenance of main spindles

Abstract

Machine tools need to be highly reliable with minimal down time. Unintended failure incurs high costs due to repairs and production losses. Maintenance is a major cost factor and is still handled reactively to a great extent. Maintenance plans by manufacturers that recommend preventive maintenance based on operating hours are often not consistently implemented. Ideally condition-dependent preventive maintenance of the most critical and cost-intensive assemblies of a machine tool would be performed. This would enable a shift of planned maintenance times to non-productive periods and would also enable procuring any spare parts at the right time. Eventually, this would lead to cost savings. This article describes the design of a condition monitoring system for machine tools and shows examples of main spindle monitoring.