Instandhaltungslehre

Instandhaltungslehre, or the theory of maintenance, is a field in engineering and management that studies the planning, execution, and optimization of maintenance activities for technical systems and facilities. Its aim is to ensure high availability, reliability, safety, and cost-effectiveness throughout the asset’s life cycle.

The discipline covers maintenance strategies such as corrective (reaktiv) maintenance, preventive (präventive) maintenance, predictive or condition-based maintenance (zustandsbasierte Instandhaltung), and reliability-centered maintenance (RCM). It integrates concepts from asset management, reliability engineering, and operations research to balance downtime, costs, and risk.

Methods and tools commonly used in Instandhaltungslehre include life cycle cost analysis, failure mode and effects analysis (FMEA), and the use of computerized maintenance management systems (CMMS/EAM) for planning and documentation. Condition monitoring techniques—such as vibration analysis, lubricant analysis, and infrared thermography—support predictive maintenance decisions and help optimize inspection intervals and interventions.

Key performance indicators in this field include asset availability, mean time between failures (MTBF), mean time to repair (MTTR), maintenance backlog, and maintenance cost per asset. Maintenance philosophy often emphasizes safety and regulatory compliance, as well as continuous improvement through approaches like Total Productive Maintenance (TPM) or design-for-maintainability.

Instandhaltungslehre is taught within mechanical engineering, electrical engineering, and industrial engineering programs and is applied across manufacturing, energy, transportation, and facility management to optimize asset performance and lifecycle costs.