Assessing Over-Maintenance:
by Jesus R. Sifonte, P.E.
Several years
ago, my first assignment as a Maintenance Engineer was to implement a
comprehensive Predictive Maintenance Program in a pharmaceutical facility; it quite
a challenge for a junior engineer with zero field experience.
A colleague of mine with 15+ years in the
field of maintenance engineering told me not to concern myself with
implementing this new philosophy, instead, he encouraged me to strengthen the
PM program in order avoid unexpected failures.
I was new to the business and wasn’t biased against Predictive
Maintenance, so I did not pay too much attention to my colleague’s counseling
and went ahead with my project.
Besides
that, my boss had also given me a very interesting Predictive Maintenance book
where I learn that 500 companies reporting success after 5 years of implementing
a PdM program had experienced a 50% average in maintenance costs reductions. That
first program we implemented was a complete success in terms of failure
prediction and is still running today. Sometime
after that, I was put in charge of the plant’s PM program and faced a new
challenge: “How do I make sure these two programs are not overstepping each
other’s boundaries?
Maintenance costs represent a major part of the total
operating costs for most manufacturing plants. Depending on the specific industry,
maintenance costs can represent between 15 to 60 percent of the cost of goods
produced. Surveys of maintenance
management effectiveness indicate that 33% of the money spent in maintenance is
wasted because of unnecessary and improperly applied maintenance. The result of ineffective maintenance
management in the United States represents a loss of about $60 billion each
year. The losses in production time and product quality (according to reference
1) that result from inadequate maintenance management have had a dramatic
impact on the US industries’ ability to compete against other countries with
more advanced manufacturing and maintenance management philosophies.
Over-Maintenance is killing our Maintenance Budget.
There is no doubt that Predictive Maintenance (PdM) is good
and proven to detect first stages of machine failures.
Successful programs have reported an average reduction of
unexpected failures by 55% and top notch programs were
reportedly able to reduce them by more than 90% after 5
years of implementation. But, What do you do after you
get the tools, the contracts, tech reports, etc? How
can you convert your Maintenance Program into real savings?
The first step you should take is having your
PdM program talk to your PM to avoid redundancy.
It makes no sense to use Oil Analysis Techniques as part of
your PdM program and at the same time perform time based oil
changes in your PM program. Likewise, time based
bearing overhaul is no longer needed as part of your PM’s if
you have a fine tuned vibration analysis program for
rotating equipment. Even then, PdM is not able to
reach a high level of excellence just by itself. There
has to be a perfect synchronization between PM, PdM, and
Corrective Maintenance crews, and this is achieved through
proper maintenance management systems. This sounds very
simple, but requires the touch of an experienced maintenance
professional; certainly PM and PdM program assessment is not
a job for amateurs, since giving the task to an
inexperienced person to reduce implementation costs may
result in taking too long to implement a comprehensive
maintenance program and thus paying less now certainly would
not mean getting more later. Even the spare parts room
is a key player in cost reduction, since most failures can
be predicted, and parts can be ordered accordingly instead
of having them on the shelf.Some successful companies have
reported a 30% reduction in parts inventory. Secondly,
revise your PM contractssince most of them rely on costly
time based repairs or overhauls that can be assessed
properly in your PdM program. Maintenance for machines like
Chillers, Air compressors, Electric Generators and Turbines
are mostly outsourced and represent a big piece of the
maintenance budget pie.
I have a good and a
bad story about OEM PM contracts. One of our customers
was able to move a PM based OEM recommended bearing overhaul
of two chemical bulk product centrifuges forward about one
year to accommodate extra production volume by just
monitoring them bi-monthly with vibration signature analysis
which revealed no bearing wear signs for both units.
This successful move brought them extra capacity
(Productivity), saved money by avoiding unnecessary
maintenance, and extended the machines useful life for and
extra year. Also they avoided running their machines
through a “Break In” stage after repair in the middle of an
aggressive production campaign. On the other hand,
another customer was forced to an early bearing overhaul on
a similar machine due to high vibration problems. But
the machine still presented high vibrations after the
bearing overhaul performed by the manufacturer and vibration
analysis was then performed: unbalance was detected.
The problem was due to an incorrect rotor assembly that
shifted factory placed balancing weights out of position
during a cleaning operation. This customer production was
delayed by several days and had to pay for a costly
overhaul, which ultimately did not fix their problem.
There are many sources of
Over-Maintenance, that if addressed properly can make a real positive impact in
your maintenance costs. Some of them are:
1)
Your
PM Program
2) Most
Maintenance Contracts for Specialized Machinery
3)
Unnecessary
Equipment Overhauls
4)
PM
based Oil Changes
5)
Your
Calibration Program
6)
PM
based filter changes
7)
Excessive
Spare Parts
8)
Unreliable
Predictive Maintenance Programs
You may ask yourself “Where do I start
from and how big is my cost reduction potential? Well, start by taking a look at your
maintenance costs for the last fiscal year.
Then, carry out a Pareto Analysis
to identify the major offenders. Also
have your finances department tell you how much maintenance costs represent to
the total operation costs of the plant.
You will find that the saving potential opportunities are significant,
and will join the number of plants reporting an average of 50% savings on
maintenance related costs. I will give
you some tips that will help you to cut down your maintenance costs:
1)
Invest in a Comprehensive PdM Program
including: Oil and Vibration Analysis as well as Infrared
and Ultrasound Surveying. You may contract an external
company, or do it yourself, depending on the skill level of
your personnel, training and, availability.
2) Perform periodical Energy Conservation Audits as part of you PM program. This was
referenced to in an earlier paper (LINK
TO: There is profit in your Power House)
3)
Synchronize
your PdM and PM
program by evaluating your PM program tasks to avoid redundancy.
4)
Evaluate
your Maintenance Contracts.
You will find a lot of expensive time
based tasks.
5)
Get
rid of Unnecessary Maintenance Overhauls
by strengthening you PdM program detection capabilities.
6)
Train
your people
to
become proficient in modern and cost effective maintenance techniques.
7)
Eliminate
PM based Oil changes.
Rely on your oil analysis program.
8)
Calibrate
your Calibration Program. These programs become inefficient and time
consuming. This subject will be assessed
in an upcoming technical article.
9) Revise
your Spare Parts Inventory
.
The less you know about your machine failure modes, the more parts you have to keep.
10)Eliminate
PM based Filter Changes.
Other indicators, like pressure drops,
may be used as criteria for a filter change instead of it being time based.
Over-Maintenance is one of the aspects leading to an increase
in maintenance and total operation costs in a manufacturing plant. Let’s identify it, face it and let those
expenses become profit to your organization.
You have the power to increase your machinery’s useful life and to boost
your plant productivity and profitability by just taking care of the factors
contributing to Over-Maintenance. Just,
do it!