Maintaining the balance

摘要

Today's CNC machine tools have extremely fast spindle speeds, feeds and rapid traverse rates, yet must also achieve high positioning accuracy and maintain tolerances throughout a production run. Such demands are of course the driving force behind the current trend to implement preventive maintenance (PM) programmes on the shop floor. Preventive maintenance, by definition, is a schedule of planned actions designed to preserve and enhance equipment reliability in order to prevent breakdowns. Therefore, in a production engineering environment, the chief objective of PM and any similar programmes, such as Reliability and Maintainability (R & M), Machine Tool Variability Management System (MTVMS), and Total Productive Maintenance (TPM), is to predict when a machine will fail or go out of tolerance to reduce unplanned downtime, particularly at critical production periods.