Preventative and corrective maintenance

Preventative and corrective maintenance

Preventative Maintenance

  • Preventative maintenance refers to regular, routine work completed to keep equipment running and to prevent any unplanned downtime or expensive repairs.

  • The objective of preventative maintenance is to maximise the availability and reliability of equipment and systems, extending their useful life.

  • Scheduled inspections and maintenance tasks at regular interval forms a crucial part of preventative maintenance. This involves activities such as cleaning, lubrication, minor adjustments, and component replacements.

  • Having a maintenance schedule based on equipment’s operational hours, wear and tear rate or recommendations from the manufacturer.

  • Documenting the history of preventative maintenance not only demonstrates compliance to safety regulators but also helps in predicting future equipment failure modes.

Corrective Maintenance

  • Corrective maintenance involves any tasks undertaken to correct a fault so that the failed equipment, machine, or system can be restored to an operational condition.

  • This maintenance type is often a reactive approach, as it’s performed after a fault has occurred, but it can be a part of a proactive strategy if it’s following the identification of potential issues during preventative maintenance.

  • Corrective maintenance tasks include the repair or replacement of parts, fault isolation, and often more extensive overhaul or a total replacement of the systems or equipment.

  • When doing corrective maintenance, the aim is to minimise the downtime, return the asset to its desired working state, and avoid interruption of production.

  • As with preventative maintenance, recording all actions taken during corrective maintenance helps to build a history of machine behaviour.

Key Differences

  • The main distinction between preventative and corrective maintenance lies in when they are executed. Preventative maintenance happens before a fault occurs to prevent it, while corrective maintenance occurs after a fault to correct it.

  • A balance between preventative and corrective maintenance is often established in an organisation to optimise both equipment reliability and cost-effectiveness. Too much preventative maintenance can lead to unnecessary labour and part replacement costs, while an over-reliance on corrective maintenance can lead to increased down-time and more extensive repair requirements.

  • A well-functioning maintenance system will be characterised by a carefully measured mix of both preventative and corrective maintenance, informed by an understanding of the operational context and backed up by accurate record-keeping.