What is maintenance?
• It is the “combination of all technical and
administrative actions, including supervision
actions, intended to retain an item in, or
restore it to, a state in which it can perform a
• Maintenance is a set of organised activities
that are carried out in order to keep an item
in its best operational condition with
minimum cost acquired.
Reducing breakdowns and emergency
Optimising resources utilisation.
Improving spares stock control.
Optimising the useful life of equipment.
• The required repair, replacement, or restore action
performed on a machine or a facility after the
occurrence of a failure
• The failure of a component in a system is
• It is the oldest type of maintenance
• Complete use of material and machine
• The cost of performing this type of maintenance
activities is lower than performing other types of
• The maintenance carried out at predetermined
intervals or according to prescribed criteria and
intended to reduce the probability of failure
• It is good for those machines and facilities which
their failure would cause serious production
• Breakdowns and emergency repairs are
• Increased component’s life
• Annual production capacity can be exactly
• In this type, actions such as
repair, replacement, or restore will be carried out
after the occurrence of a failure in order to
eliminate the source of this failure or reduce the
frequency of its occurrence.
• Corrective maintenance is different from run to
failure maintenance in that its activities are
planned and regularly taken out to keep plant’s
machines and equipment in optimum operating
• Maximisation of the effectiveness of all critical
• Elimination of breakdowns.
• Elimination of unnecessary repair.
• Set of activities that are used to eliminate the
cause of maintenance, simplify maintenance
• Raising machine performance from the
maintenance point of view by redesigning
those machines and facilities which are
vulnerable to frequent occurrence of failure
• Set of maintenance activities that are
performed on a machine or a facility when an
unplanned opportunity exists during the
period of performing planned maintenance
activities to other machines or facilities.
• Separate time for maintenance activities for
such machines need not be scheduled
• Effective usage of man power and energy
• Depends on continuous or periodic condition
monitoring equipment to detect the signs of
• Example : Boilers – Hairline cracks
Reliability Centred Maintenance
• It is a process used to determine the
maintenance requirements of any physical
asset in its operating context.
• Able to focus maintenance activities on
• Example : Nuts and bolts of ladders are of
least importance when compared to baffles of
Total Productive Maintenance
• Total Productive Maintenance (TPM) is a
maintenance program which involves a newly
defined concept for maintaining plants and
• The goal of the TPM program is to markedly
increase production while, at the same
time, increasing employee morale and job
Objectives of TPM
• TPM was introduced to achieve the following
– Avoid wastage in a quickly changing economic
– Producing goods without reducing
– Reduce cost.
– Produce a low batch quantity at the earliest
– Goods sent to the customers must be non