Preventive maintenance anticipates failures and adopts necessary actions to check failures before they occur. It includes activities like inspection, lubrication, cleaning unkeeps, minor adjustments and replacements found necessary at the time of inspection etc.
Preventive maintenance can be either: running maintenance or “shut down maintenance”.
Running maintenance includes maintenance activities e.g. minor adjustments in machines revealed through inspections, lubrication, cleaning and upkeep etc., which are carried out when the machine is still running.
Shutdown maintenance includes preventive maintenance activities such as minor component replacement whose needs are identified through inspections, which require stoppage of machines.
Preventive inspection is one of the key activities of preventive maintenance which is usually performed by making use of human senses watch (eye), listen (ear), touch (hand, leg, body smell (nose) and taste (tongue). But the trend is changing towards use of condition monitoring instruments. Such maintenance. Practice is known as predictive maintenance or condition based maintenance.