Approaches to Maintenance 131

autonomous maintenance

A maintenance technique in which tasks are performed by the machine operator rather than maintenance staff. Autonomous maintenance is a element of total productive maintenance.

baseline reading

Initial data collected while a machine is in working order. Baseline readings are compared to future readings in order to detect machine problems.

computerized maintenance management system

CMMS. A type of management software that performs functions to support operations and maintenance programs. Facility personnel can use CMMS to track and monitor the time and costs associated with maintenance.

condition-based maintenance

CBM. A type of predictive maintenance which depends on continuous or periodic monitoring to both anticipate failures and alert machine operators to potential problems. CBM is a type of predictive maintenance.

corrective maintenance

CM. The practice of performing maintenance on a machine after a problem becomes apparent but before the machine fails. CM corrects problems before reactive maintenance is necessary.

downtime

A period of time when production stops, often due to mechanical failure or maintenance needs. Downtime can be planned or unplanned.

lean manufacturing

An approach to manufacturing that seeks to improve quality, reduce cost, and eliminate waste. Total productive maintenance is a maintenance approach used in lean manufacturing.

maintenance

Any activity that contributes to the care and upkeep of machines or equipment. Maintenance approaches can involve monitoring equipment for problems or fixing a machine after it breaks down.

maintenance planner

A person who schedules and coordinates maintenance activities. Companies with large maintenance departments often hire maintenance planners.

overall equipment effectiveness

OEE. A lean metric that measures how effectively equipment is being used. Overall equipment effectiveness is determined by multiplying the percentage of an equipment's availability, quality, and performance together.

planned downtime

A scheduled stop in production which is often used for machine maintenance. Planned downtime is preferable to unplanned downtime, which is usually caused by machine failure.

predictive maintenance

PdM. A maintenance approach that tests and monitors each machine individually in order to predict failures. In PdM, periodic readings are compared to baseline readings in order to identify problems.

preventive maintenance

PM. The practice of performing standard maintenance functions on a scheduled basis in order to prevent breakdowns. PM tasks are usually determined by the age of the equipment.

reactive maintenance

RM. The practice of performing immediate maintenance on a machine only after it becomes damaged or problematic. RM is not a cost-effective long term maintenance approach.

reliability-centered maintenance

RCM. A maintenance approach that identifes the maintenance requirements for each machine based on the needs of the work environment. RCM prioritizes some machines over others.

run-to-failure

A maintenance policy that allows equipment to run until it breaks down, at which point reactive maintenance may be performed. Run-to-failure is typically used for low-priority machines.

total productive maintenance

TPM. A comprehensive maintenance approach that gives continuous attention to equipment in order to reduce waste. TPM encourages employee participation and incorporates lean manufacturing principles.

unplanned downtime

An unexpected stop in production due to maintenance, mechanical failure, or other processing problems. Unplanned downtime can lead to safety problems and production losses.

vibration analysis

A maintenance technique that measures levels of machine vibration in order to determine if the machine is functioning properly. Increases in vibration usually indicate a problem.