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Preventive Maintenance
Increasing Equipment Efficiency and Planned Work
By Rey Marquez, Life Cycle Engineering
The idea of Preventive Maintenance has matured into a powerful
factor throughout industry. PM’s or Preventive Maintenance has
grown due to contributions of knowledge worldwide. Three major
areas any organization looks at are:
·
Number of Work Orders produced
·
Total Maintenance Hours
·
Maintenance Costs
Critical to any organization is being able to identify and
control activities within both the Operation and the Maintenance
areas. Efforts to ensure the reliability and maintainability of
equipment begin with a solid PM/PdM structure.
Preventive maintenance –PM- is a time based strategy conducted
at a set interval or predetermined time when a piece of
equipment is taken off line and inspected and based on the
inspection repairs are made and the equipment put back on line.
Predictive maintenance – PdM- is a condition based approach; it
is based on monitoring and measuring the condition of equipment
in order to assess any needed corrective work. The table below
shows the four different maintenance categories used in
industry.

The result of moving form Reactive maintenance to planned
scheduled repairs is significant to the maintenance repair
budget.
Repairs take time and time is MONEY!!!
New and advanced technology will help reduce costs and increase
equipment reliability however; business changes must be such
that a company operates a profitable operation.
A comprehensive maintenance evaluation is needed in order to be
able to measure maintenance functions i.e. Planning and
Scheduling, PM process, Continuous Improvement process, etc.
Consequently, a well thought out strategy must be put into place
which will yield maximization of capacity utilization and
availability.
Business changes need to such that a company can operate in a
profitable manner; the management and controlling assets will be
the difference between acquiring a profitable business or one
that claims a loss. A solid comprehensive Maintenance management
strategy consists of:
·
Planning
·
Scheduling
·
PdM
·
Continuous Improvement
In this section we will concentrate on the PM-Preventive
Maintenance area.
It will cover: Determined Planned-level of Maintenance & PM
strategy.
Rx-TPM/PM Strategy:
The principles of Total Productive Maintenance (TPM) demonstrate
that solid maintenance practices are essential for effective
TPM. For example the following is required to begin building a
foundation for this solid process:
·
Team Building: Maintenance planner, Maintenance Engineer,
maintenance teams
·
Maintenance goals and objectives defined
·
Determine Planned work level of maintenance: PM’s; PdM;
Corrective work
·
Communication: Communication lines open between Operations and
Maintenance
·
Accountability: Compile Bad actor list; review current Work
Order system and process; establish PM guidelines
·
Action: Develop and Implement a disciplined approach for
equipment condition monitoring; increase equipment reliability
and efficiency
·
Develop a positive work environment
Some important factors to consider are:
-
Asset
Functions: What are the functions of each asset?
-
Asset
Failures: How does each asset fail and how often?
-
Failure mode: What is the cause of failure?
-
Failure effect: What effect is incurred with each
failure?
-
Consequence of failure: How can each failure of the asset
be prevented/predicted?
Developing a structured Planning and Scheduling maintenance
process will address these kinds of issues as shown in Figure 1.
The process is made up of four key components as shown below:
Within these four components PM tasks require their respective
data to be developed as each task corresponds to a piece of
equipment which may require spare parts or special tools. All
of the data from the equipment and inventory databases play a
role in the development of PM tasks and their frequencies.
Information that is required includes the steps to perform the
actual maintenance as well as safety instructions and spare
parts lists.
The key to developing and implementing a successful preventive
maintenance process is understanding preventive maintenance
itself. Preventive maintenance – PM – is a component of
proactive maintenance (PAM) as shown in Figure 2.

However, it is probably the most misunderstood, the methodology
or technique applied to develop a successful PM process, is not
determining what to do moreover, it is implementing the process.
Any PM or other maintenance discipline such as, PdM-predictive
maintenance,
RCM-reliability centered maintenance, etc. should be considered
as a process and not as a program. The difference is a
program has a start and an end; a process is dynamic, a live
document of action items and procedures.
In order to implement a successful PM process we must first
build a solid foundation. This consists of:
·
Planning methodology
·
Initial Plan & Strategy
·
Establish Standards
·
List of assets to track
·
Partnerships; Operations & Maintenance / Purchasing &
Maintenance
·
Criticality assessments
These are only a few areas, which make up a successful PM
process. To begin, a maintenance planner must be in place and a
reliable CMMS available. Every PM process developed and
implemented will become unique to the plant it is used in.
Standard PM lists or charts developed by manufacturers are only
a guideline or start; these do not include a particular plants
equipment history or practical use.
A well structured PM process opens the door to many exciting and
profitable avenues, for example, the opportunity for reverse
engineering in plant processes, introduction of vibration
analysis, thermography, oil analysis and so on. Once the PM
process is coupled with PdM-predictive maintenance techniques
increased asset management effectiveness will be realized and
plant performance barriers removed.
All the management parties must declare ownership before rolling
out any TPM effort. By using these principles all users will be
trained on the software’s features and functionalities. They
should be able to understand how the software impacts and
supports the initiatives of their Organization’s business
process.
A very important step in the TPM strategy is to conduct a
performance assessment.
Assessing Maintenance Performance requires measurements that
are:
·
Finite
·
Repeatable
·
Real
The initial assessment should provide an in-depth look at a
given site and a consensus, which provides a priority of issues
that the team can use to drive the strategic planning. Second,
a more quantitative process must take place, which includes
scoring the site against an excellence model or best practices
model.
The assessment process delivers an enhanced view of maintenance
practices, which are in need of improvement. The main issue is
to establish a clear objective for implementing the strategic
planning. Strategic planning efforts often are overwhelming
because of the large list of tasks required for the
implementation.
Detailed PM sheets must be developed to capture the activity and
history of equipment therefore; the old PM checklist must be
abandoned! PM checklists do not show what actual PM work or
activity was performed during the scheduled PM on a given asset.
The detailed PM sheet is comprehensive and allows for feedback
from the craftsman to the supervisor and planner. See Figure 3.
Unlike a detailed PM sheet, the typical “Old style” PM sheet
does not offer any room for improvement or any opportunity to
allow for a complete PM inspection. The old PM sheet as seem in
Figure 4; is more like a check-off list whereas, the detailed PM
sheet allows for valuable information from the technician that
helps develop the Work Order.
Consequently, work orders are generated from the detailed PM
sheets and work is assigned as required. One area that is
greatly misunderstood is the relationship between
Operations/Maintenance. When the PM process is implemented the
operational team has a big role to play and ensure that the
operation/maintenance marriage is successful.
Reliability covers a wide spectrum of advanced maintenance
technologies, some of these are fairly simple to put into place
and others require a more thought out plan and implementation.
The advanced techniques produce data that is instrumental in
avoiding equipment failures and can help predict the potential
failure of a given asset.
The strategic plan will also include the following areas:
•Determine planned level of maintenance
•Team Building:
·
Develop alliance between Maintenance, Operations & Purchasing
•Communication:
·
Develop & communicate plan to implement new P/S, how it will be
done and its effects on all employees
•Accountability:
·
Establish who will champion the PM/Scheduling efforts and how
this will be executed
Successful PM/Scheduling implementation is dependant on how well
it is prepared and planned; a formal detailed plan integrates
Maintenance, Operations, and Purchasing and Quality issues
forging a business alignment.
Part of the Strategy Plan is to develop and establish a solid
foundation outlining the work to be done in simple logical
steps. First a review of the current PM and work procedures,
equipment history and MRO, inventory, BPF – Business Process
Flow charts – and maintenance costs to name a few.
Steps required before beginning a formal plan are:
·
Identify steps needed to begin: i.e. PM modifications,
Scheduling process, etc.
·
MRO: Materials management, Purchasing, warehousing, etc.
·
Maintenance management: Work Order process, PM’s, PdM, equipment
hierarchy and history.
·
Coding: Equipment coding, parts coding, etc.
·
Set standards of Frequency and types of work to done,
performance quality, reporting format and MTBR measures.
·
Obtain and keep Senior Management support
·
Vendor selection
One top issue is to get the most out of the PM/Scheduling being
implemented. Company culture, management philosophy and style
are some of the top issues which seriously need attention. Part
of this company culture and philosophy when enrolled in the
Preventive Maintenance effort will help yield cost benefits.
COST BENEFIT
Senior Management support is critical to the success of the
PM/Scheduling effort. This support enforces the discipline
required to obtain full cooperation from all those involved
whether directly or indirectly with the implementation and
roll-out.
Business intelligence provides features, which include: tracking
maintenance costs, cost per volume produced, equipment analysis,
total cost of repair or replacement costs.
Use of a solid PM/Scheduling process will help build an accurate
equipment history and comprehensive analysis capabilities; this
will help to balance the cost of maintaining vs. replacement.
All these fundamentals that affect Maintenance Planning and Work
Flow must be considered.
Balance
Keeping a balanced view and perspective of the Preventive
Maintenance effort is critical in order to obtain maximum
results and optimize benefits work practices must be formally
changed in a structured planned methodology. As results are
obtained, feedback and control loops can be use to compare the
new data with the original plan.
Specific feedback includes:
-
Job
Control / Daily Scheduling: This describes how work is
distributed within the workforce. It includes priorities for
planned work.
The Final outcome will provide:
WIN / WIN
RESULTS!!!!!!!
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