FROM REACTIVE MAINTENANCE TO
PROACTIVE PREVENTIVE MAINTENANCE
SYSTEM

S Safi1 & S Mozar1,2
1Covaris Pty Ltd 2PhD Candidate Macquarie Graduate School of Management
Summary: A maintenance system is presented in this paper that has been implemented in a
number of companies. The system has four key elements. The first element is specifying all
equipment to be maintained in a hierarchical system, covering issues such as criticality of
equipment. The second element is development of an efficient but comprehensive maintenance
procedure database. The next key element is provision of a master maintenance schedule that
ensures all registered equipment is covered by an appropriate procedure. The last element is
implementation of the maintenance system through load-up to a computerized maintenance
management system (CMMS) of choice. The main outcomes from introducing the proactive
preventive maintenance system includes moving the site from breakdown maintenance to
preventative maintenance, ensuring that all statutory compliance obligations are met, eliminating
frequent causes of loss of reliability and reducing the cost of maintenance.
Keywords: Maintenance System, Breakdown Maintenance, Preventative Maintenance, Scheduling,
Change Management.
1 INTRODUCTION
In a typical reactive system most of the effort of the maintenance team is spent on responding to breakdowns. There is little or
no planned maintenance activity, and work is prioritised in a random manner (responding to breakdowns) with no regard to the
business drivers. Such a regime keeps the organization operational, but at a very high cost. The cost is high due to the
unplanned stoppages in production that are frequently associated with time lost in obtaining spares to complete the repair. In
such a regime it is difficult to complete preventive maintenance procedures (PM) as maintenance staff are constantly
responding to breakdowns (BD). Very little if any time is allocated to PM work. The unpredictable and random nature of
breakdowns does not allow work to be planned. Frequently such systems do not keep records of work done that would enable
reliability engineers to attack major reliability issues.
A proactive maintenance system is not free of breakdowns, but the breakdown can be related to the organization’s business
drivers via assigned criticalities. A piece of equipment that has a low criticality assigned to it can be scheduled into next weeks
planned activities. A proper managed maintenance plan allows capacity to attend to urgent breakdowns, i.e. those with a high
criticality. It also allows the maintenance team to control the maintenance activity, rather than to be controlled by it.
Equipment that receives adequate maintenance is less likely to fail, which makes it possible to have planned maintenance down
time. Planned down time is far less costly than unplanned down time and does not have the associated loss and poor quality
product associated with a BD. If a breakdown occurs on equipment that has been regularly maintained, the damage is generally
not as bad as that on poorly maintained equipment. Apart from eliminating the operational inconvenience associated with a
breakdown regime, a proactive maintenance system also results in a more cost effective maintenance system. This paper
describes the four key elements of a proactive maintenance system, as the authors have implemented in a number of
organizations and in a variety of industries.
2 PLANT DICTIONARY
The level of detail that is necessary for adequate maintenance systems design is quite extensive. This is often a major problem
to the improvement team given the poor state of documentation and local knowledge regarding some machines, despite their
criticality to the process.
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ICOMS-2004 Paper 029 Page 2
Cluster mapping is an important technique for the team to understand the scope of a machine/process and its maintenance
requirements. It is a means by which a complex machine is broken down into a logical hierarchy of maintainable items. A
maintainable item is defined as an item for which an inspection is warranted.
Cluster maps are also there to ensure that the team does not waste time by delving so deeply into the machine that the team
does not take advantage of both the trades competency of the people who maintain at the component level and the fact that
much of the machine is designed to last until its end of life.
An example of a cluster map used in a food factory maintenance improvement process is shown below (1):
1.3
Loaf
weigher
1.6
Pneumatic
system
1.5
Electrical
cabinet
1.
Schiwa Slicing Machine
1.2
Laser belt with
scanner
1.7
Feed unit with spindle
& collate chuck
1.1
Loader/Roller
conveyor
1.4
Machine frame
support
1.8
Product holddown
device
1.9
Slicing device
with drive unit
1.10
Operators
panel
1.11
portioning
unit 1
1.12
Control
unit
1.13
Safety
device
Figure 1 A Typical Cluster map
The system shown is a slicing machine. By tracking the system it is possible to simply determine a number of issues:
· Lowest maintainable units to be covered by the PM system
· Guide document to facilitate the criticality assessment process
· Identification of common types of equipment to facilitate the use of Standard Job Procedures
We recommend a three-tier policy for generating the plant dictionary:
1. The top tier is a multiple layer of levels assists in identifying the system or machine
2. The second tier may be one or more levels that are used to logically identify a group of maintainable items – the PM work
order covering one or more inspections is assigned to an entity at this level. We try to use the minimum possible number
of levels (i.e. one).
3. A maintainable item that needs to be checked or inspected – a PM work order is not usually provided for an item at this
level but is more normally associated with a singular task such as a corrective maintenance work order or a breakdown.
4. The plant dictionary is structured according to a parent-child hierarchy outlined by the cluster maps. The plant dictionary
includes important equipment information such as manufacturer, date of supply, serial number, criticality, equipment and
location identifiers.
With respect to setting up the plant dictionary in a CMMS PMs (preventative maintenance work orders) will be attributed to
level 2 items so these definitely need to be in the CMMS plant dictionary. However we may want to assign breakdown and
corrective maintenance tasks to the level 3 items, so these also need to be loaded into the plant dictionary – this is a decision
for the team putting the system together. There is often a tendency to attribute corrective work too high in the plant dictionary
so that failure modes cannot be easily identified from the maintenance history. Hence an effective plant dictionary is one
where a corrective task attributed to a child dictionary item clearly indicates the instance of a type of failure that may then be
amenable to improvements in the maintenance plan.
3 MAINTENANCE PROCEDURES AND ROUTINES
This section is concerned with the identification and specification of Maintenance Strategies. These are procedures that specify
a range of tasks for a specific type of maintainable item. The strategies set will be consequently allocated to many incidents of
the same type of equipment across the site.
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ICOMS-2004 Paper 029 Page 3
The procedures are divided into three levels:
Level Attributes of the level Expected personnel to conduct
the level
1 Regular inspection that does not require the maintainable item to be
opened up or, in most cases, halted for the work to take place.
Either Trades competent maintenance
staff or local operating staff
2 Detailed trades procedure. Normally requires the maintainable item
to be stopped and access allowed.
Trades competent
maintenance staff
3 Expert or third party inspection of the maintainable item, commonly
associated with condition monitoring. Can also refer to an expert
NDT inspection, inspection by the machinery supplier or an
external expert.
Scientific experts or 3rd party
personnel
Table 1 Three Levels of Procedures
The system does not specifically cope with the following types of tasks:
· Daily checks – these are considered to be parts of the Standard Operating Procedure.
· Non-routine refurbishment or rebuilds – these should be treated in a long-range maintenance plan, which can be
provided under an asset management plan product.
The relationship of maintenance strategies to procedures and routines is identified below:
Figure 2 Maintenance Strategies
3.1 Procedure Design
The process for designing a procedure is as follows (see Figure 3):
1. Ascertain that no other procedure is relevant to the type – allowing for the fact that we may need more than one
procedure for a type, based on variances in manufacture or design.
2. Identify the scope of the procedure based on elements on the plant dictionary – note that a procedure can cover
more than one element. For each of the following steps work around each of the elements in a consistent
manner.
3. Review the failure modes that are amenable to simple inspection and list suitable inspection tasks – action plus
location of inspection. These tasks should include all external observations.
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Strategy
Maintenance
Strategy
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PProrocceedduurere
PProrocecedduurere
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RRoouutitninee
1155hhpp E Elelecctrtircic M Moototor r 10-25 hp Electric
Motor Strategy
10-25 hp Electric
Motor Strategy
MMoonnththlyly E Elelectcrtircicaal l
22 y eyeaarlryly O Oveverhrhaauul l
Annual Condition
Monitoring
Annual Condition
Monitoring
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MMoototor r6 61122222233
MMoototor rE E114455667777
MMoototor rV V66YYYY3344
MMoototor r6 61122222233
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MMoototor rV V66YYYY3344
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Example MMoototor rE E114455667777
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ICOMS-2004 Paper 029 Page 4
4. Note all internal checks that are required for inspections. List tasks according to area of access – what has to be
stripped down to allow access. Determine if task is electrical or mechanical (note that all structural checks are
considered mechanical). These tasks are also requiring trades expertise so calibration checks can be included
here if undertaken by a trades person and not an external expert. If an external expert is required, refer the job to
Level 3.
5. Determine task frequency and expected duration of the work – used for scheduling purposes.
6. Identify all functional testing that should be conducted – exercise of machine, exercise of alarm, exercise of
limit switches, etc.
Create a
Procedure
Item in the
Plant
Dictionary
List of
components
Manufacturer
recommendation
Calibration
Adjustment
Procedures
Translate to CMMS
format
Standard Stored
Procedure
- common type of
equipment
Standard
components
Commonly
occurring problems
Corrosion, oil level,
lubrication, wear
What fails
What needs
adjustment
Necessary
inspection - what to
look at, what to
look for
Level 1, 2, 3 task
Procedure
Uncertain about
what fails
Talk to local
person
What has failed in
the past
Frequent
failure
What do they
do
Can this be
anticipated by
a check
Check or
change
Infrequent or no
failures
Have you heard of
problems in this
equipment before
Run to failure
Stream directly into CMMS
Adapt for site
conditions
No
Yes
Figure 3 Procedure Design
Assigning a procedure to a specific item of equipment creates a routine. Specifying the timing of the first release of the routine
as a work order is an important issue to obtain a balanced workload during the year and avoid the backlog built-up during the
busy period of the year for the particular site. Adjusting the duration of the routine is required to allow for either travel or
access to the equipment. Considerations in the timing of a routine can include:
Maintenance routes, e.g. lubrication rounds, where a number of routines are completed at the same time
Lumping of routines together based on the location of the equipment, eg servicing a plant room or servicing a line when it is
down
Isolation requirements – how much equipment, up to the entire facility, needs to be off line
4 MASTER MAINTNENCE SCHEDULE
The previous section of this paper covered the generation of maintenance procedures and routines for maintainable items.
Preventive maintenance work needs to be planned. The process for scheduling preventive maintenance work is provided in
this section. This process sets out the generation of preventive work prior to it being loaded to the CMMS database.
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ICOMS-2004 Paper 029 Page 5
Specifying the timing of the first issue of the routine as a work order is accomplished by Master Maintenance Schedule (MMS)
worksheets.
To manage and develop a Master PM Schedule, Covaris uses a spreadsheet program, which has to be linked with the works
management system database. The PMs are entered, checked and forecasted in this spreadsheet. The Master Plan covers all of
the defined criteria and will upload critical start dates and estimates of times to the CMMS.
The Excel spreadsheet has 365 columns to simulate all calendar days as shown in Figure 4 (2). On the left hand side, all of the
equipment and related job-plans (regarding the equipment type PM strategy) are listed. The man-hours of each job are also
assigned in the “duration” column.
Figure 4 A Typical Master Maintenance Schedule
In developing the MMS, scheduler defines the first release of each procedure, yellow cells in Figure 4. The program then
automatically allocates the subsequent dates when the routine is due. At the bottom of the Excel spreadsheet, the workload per
day is calculated and if it reaches the pre-defined maximum load, the cell back-colour changes to Red.
The other feature of the Master PM scheduler is that it provides a forecast all of the work-orders for the planned PMs in an
environment outside the works management system database. The scheduler can check a variety of graphs specifying the
workload for each trade or the total workload for the preventive maintenance for the entire site or a particular department.
These graphs help the scheduler to examine the effectiveness of the scheduling and to avoid congestion in any particular week,
during the busy period of the year or for a specific trade. Figure 5 shows a typical workload for preventive maintenance for a
site with 100 hours per week available for PMs (2).
The Master Maintenance Schedule manages subsumption of routines (e.g. monthly into 3 monthly, etc) and seasonality of
routines. Based on the MMS, it is possible to set the timing of routines.
An Implementation Plan for the go-live of the PM system is also an important part of a well-defined MMS. The importance of
this spreadsheet is to define a smooth path from breakdown maintenance to a planned maintenance system. It will provide
sufficient information for developing a smooth transition in the plant considering available resources and existing workloads
on maintenance crews.
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ICOMS-2004 Paper 029 Page 6
Figure 5 A Typical Workload
5 REPORTING KEY PERFORMANCE INDICATORS
A healthy maintenance management system should always be monitored with appropriate reporting system. The overall view
of a maintenance planning and scheduling system is provided below. This identifies the key elements that are necessary for a
well-controlled maintenance system. Two key metrics shown in Figure 6 are percentage of PM content in all scheduled work
and percentage of scheduled work in total work done per week.
Figure 6 Overall Planning and Scheduling System
Key performance indicators (KPIs) form the basis of the monitoring process for performance-based maintenance. Use of the
various KPIs will be dependant on the capability of the information system to provide accurate data for calculation purposes.
Most CMMSs are capable of capturing most of the information necessary for these KPIs. Others should be developed in
collaboration with production departments and require more involvement from the management to become alive (3).
Master Maintenance Schedule
0
10
20
30
40
50
60
70
80
90
100
Week 40
Week 42
Week 44
Week 46
Week 48
Week 50
Week 52
Week 2
Week 4
Week 6
Week 8
Week 10
Week 12
Week 14
Week 16
Week 18
Week 20
Week 22
Week 24
Week 26
Week 28
Week 30
Week 32
Week 34
Week 36
Week 38
Hour
REACTIVE
REACTIVE
Work done by trades staff/contractors
Maintenance schedule for the week
Maintenance Plans - PMs
Corrective Maintenance backlog
Urgent call-outs
1
2
PROACTIVE
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ICOMS-2004 Paper 029 Page 7
Based on Figure 6 the recommended KPIs are shown in Table 2. In general both a target value and a transition value are
indicated. The transition value should be adopted for the first year of operation at the site.
Poor Maintenance Target Transition
1 % PM Work orders in weekly schedule <40 85 60
2 %Work completed in a week which was
scheduled the week before
<40 80 60
Table 2 Key Performance Indicators
Table 3 shows the data of a case study for the first six months of the introduction of a maintenance system (4). Both KPIs
indicate the site was in a poor maintenance condition when the maintenance system was introduced. The case study shows a
move from reactive maintenance to proactive maintenance in a period of six month from introduction of the maintenance
system.
January June
BD 71 42
CM 18 25
PM 11 37
Table 3 Case Study
January June
1 % PM Work orders in weekly schedule 38 60
2 %Work completed in a week which was
scheduled the week before
29 60
Table 4 KPIs for the Case Study
6 CONTINUOUS IMPROVEMENT
The proactive maintenance system is not the end of an improvement journey. Rather it is the first step in gaining control.
Continuous improvement requires constant effort, and a good starting point is collection of reliability data, which can be stored
and retrieved as required for reliability analysis. The reliability analysis of equipment should be linked to the business drivers.
For example there is very little benefit in spending effort studying failure patterns on equipment that are of very low criticality
to the business. The payout can be very significant however, if this energy is channelled into analysing the failure of a piece of
equipment that is very critical to the business. Sometimes even a very small improvement can have a substantial impact on the
business. The point is that the more critical a piece of equipment is to the business, the more attention it should receive.
The system described sets PMs up that are time based. This is not an optimum solution, but a good starting point if no other
data is available. Over time, as data is available, and perhaps as some condition monitoring is implemented, the efficiency of
maintenance can be improved by moving to condition based PMs. Even if the organization decides to stick with time based
maintenance procedures, the intervals should be reviewed, based on criticality, and adjusted if required.
Equipment that causes problems should be identified and studied with the aid of FMECA (failure mode, effect, and criticality
analysis) in order to better understand failure mechanisms and from develop more meaning checks and PMs. Special effort
should be made to identify hidden failures, as these are not apparent at first and when finally identified, will cause significant
failures that can result in substantial impacts on equipment availability.
So far the discussion has focused on equipment availability, but operational safety must not be sacrificed. Regular safety audits
should be conducted in order to ensure safety is maintained, and that all equipment complies with statutory requirements.
After maintenance efficiencies have started to improve, the next milestone should be the optimisation of maintenance strategies
to develop and achieve equipment life cycle strategies that are in accordance with business objectives and goals. An example
might be that in order to ensure product quality and productivity, the life cycle of a piece of equipment may be limited due to
technology induced change, rather than being due to the equipment reaching its wear-out stage. Such limitation on the machine
life cycle would have implications on the maintenance strategy.
Modern TQM based improvement strategies, such as quality improvement team, should not be ignored. Improvement teams
can be formed with members from maintenance and from production. If such teams are given realist, achievable goals, it is
often astonishing what can be done.
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ICOMS-2004 Paper 029 Page 8
7 CHANGE MANAGEMENT
One thing that should not be forgotten in this discussion is that without the support of top and middle management, the best
intentions and strategies will not bear fruit. Top management must provide the vision and make a commitment to support the
improvement initiatives and ensure that adequate resources are made available in order to achieve agreed goals. An
appropriate goal setting strategy is important, in order for goals to be achieved. Paul Meyer (5) suggest the use of SMART
goals, that is goals that are:
· Specific: goals that specify what the outcome should be.
· Measurable: an agreed upon way or method to measure progress of the agreed outcome.
· Attainable: the goal must be doable within the constraints of the organization.
· Realistic: the goal set should not be too trivial, but neither should it be too difficult to achieve given the organisational
constraints.
· Tangible: there should be a realistic time frame within which the goal(s) should be achieved.
The above steps in goal setting help identify obstacles, which helps in the planning and controlling of the out comes from these
goals.
It is equally important for management to communicate its vision for the change and the benefits for the organization to justify
pushing everybody out of their comfort zone. If no buy in is achieved, a successful outcome is highly unlikely (6).
Going into this change programme, it should be noted that there are no quick fixes. If the maintenance department is flat out
coping with BDs, it is unlikely that the same team will be able to add PM tasks to its activities without additional resources.
Contractors may need to be brought in help with the extra workload in the transition period. PMs should be gradually added to
the workload until the weekly schedule is obtained. This may take up to 12 months to achieve. It will be noticed that over time
the number of Breakdowns will decrease as the number of PMs is increased. During the transition period effective backlog
management is important. Jobs that are of low priority and risk may over time, if they are kept in backlog, become higher
priority and the risk factor may also increase. Managing the change to a proactive maintenance system requires a lot of upfront
work in planning and documenting the system. Therefore it is good to appoint somebody who knows the organization well as a
change agent to drive the changes. This person may need to be supported by an external consultant. The external consultants
can help take some of the workload of the change agent, but more importantly they are also the experts to which serve as
referees in implementing the system.
8 CONCLUSIONS
This paper presented a methodology that allows organizations to break away from a reactive maintenance regime, to a
proactive regime that is aligned with the business drivers or objectives. Four key elements were used to achieve the successful
implementation of a maintenance system. The first element is a plant dictionary that has all maintainable equipment listed in
hierarchical form. The next element is the development of a comprehensive and efficient maintenance procedure database,
which should also include safety procedures as they relate to maintenance tasks. The third element is a master schedule that
ensures all registered equipment is covered by an appropriate procedure. The last element is monitoring maintenance
management system with a reporting system. All this information is linked together in a CMMS. The CMMS will allow
efficient handling of the data and appropriate planning of work to be done. The CMMS will also store equipment data that can
be helpful in future review of current maintenance strategies and help identify which items can benefit the organization if
further improvements are made to the maintenance system. The change can only be brought about with the support of top
management and the effective communication of the organizations goals to all employees. Once the change has been brought
about successfully, that is not the end but rather the beginning of the continuous improvement cycle. Further improvements are
absolutely necessary. The proposed system is only the first step, and needs much more post project work such as PM
improvements, the implementation of condition monitoring where appropriate. Following that, the maintenance system should
evolve into a strategy that includes life cycle analysis.
9 ACKNOWLEDGEMENTS
The authors acknowledge the input of work colleagues at Covaris Pty Ltd and the many clients and research partners who have
contributed to this work.
10 BIBLIOGRAPHY
1. S Safi, S. Mozar, R. Platfoot, Maintenance Policy Manual, Covaris Pty Ltd, Unpublished Internal Document for George
Western Food, Melbourne (2002)
2. S Safi, R. Platfoot, Maintenance Policy Manual, Covaris Pty Ltd, Unpublished Internal Document for George Western
Food, Sydney (2003)
3. R Platfoot, Informed Maintenance Planning, Integrated Maintenance Summit’98, IIR Pty. Ltd., Sydney (1998)
4. Field data collected from a food industry source (2003)
5. P Meyer, Effective Personal Productivity, Leadership Management Internat’l Inc., Waco, Texas, second edition ( 1995)
6. S. Thomas, Successfully Managing Change in Organizations, Industrial Press Inc., New York (2001)