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Corrective
Maintenance Task Generation by Robert Apelgren,
Reliability Engineer
Maintenance cost or maintenance loss?
Maintenance in today’s plant is a dynamic function of
the ability to adapt to quick changes and to new
policies and management techniques. An inherent problem
common to many maintenance programs is that manpower is
one of the first things considered when cost reduction
is sought. The loss of manpower poses continuous
challenges to any maintenance manager who is striving
for world class status. Corrective maintenance
experience is one of the critical areas of expertise
that is often lost.
Plants are changing and expanding at an
ever-increasing pace to keep up with the competitive
environment in today’s society. The equipment being
produced has become more efficient and reliable to meet
the growing demand for productivity. With this increase
in efficiency and reliability, a lot of plant equipment
is now more complex in the mechanical, electrical,
hydraulic, and pneumatic systems. The days of “backyard
mechanics” in plants are coming to an end. A majority
of plants now require a degree or specialized
certification as qualifications for employment.
There are many programs that recommend
corrective maintenance task development as an
improvement to a maintenance program. Reliability
Centered Maintenance (RCM) and Business Process
Reengineering (BPR) are programs designed to move
maintenance and management programs to the next level.
Such programs consider processes and provide
recommendations for change to improve the reliability
and productivity of equipment and processes. Programs
of this nature can be a great investment and should be
researched thoroughly before undertaking the long-term
change that can be involved after an analysis is
complete. Although the programs can reap large rewards
in short and long term benefits, implementation and
follow through are the keys to truly effective
programs. This includes implementing the results,
periodic update analyses, and progress reports.
Commitment to continuous improvement is paramount to the
success of such programs.
RCM is a process that is conducted to
improve maintenance programs. The focus of RCM is
function preservation through the most cost effective,
safest, and technically feasible methods. RCM can
improve a company’s maintenance system and help increase
the overall productivity of most processes. If a
company is planning on having an RCM analysis conducted
a good corrective maintenance program can reduce RCM
analysis time and improve the results of the analysis.
If a company has not already implemented an effective
corrective maintenance program, it will generally become
a recommendation of an RCM analysis to implement one.
BPR is similar to
RCM, but on a different scale. RCM is historically
focused on maintenance. BPR as an expansion of RCM
principles, focused on change in any area of a company
with any function. BPR is an effective tool at finding
improvable areas in a management system. Manpower
reduction may be an effect of a BPR process, when cost
effective. Note that manpower reduction, especially in
the maintenance department, is not always the best
answer for cost reductions.
Cost reduction is
something that managers must continuously consider. The
quickest routes to cost reduction are not always the
wisest choices. The popular place to go for quick cost
reduction is manpower. Companies stress that employees
are their greatest asset. Yet, when it comes time for
reductions, employees are one of the first assets to be
reduced.
Manpower experience
embodies tribal knowledge within a company. When an
employee is released, a certain amount of tribal
knowledge is lost. After releasing personnel, some
companies find themselves short handed and have to hire
new employees. Training time and costs can be higher
than the cost of maintaining the personnel that were
released.
Corporate knowledge of experienced employees
is a valuable asset to a company. By effectively
capturing and maintaining that corporate knowledge, the
impact of personnel losses is reduced. This is not a
new concept to experienced managers who know the trials
of maintaining an experienced workforce. The reduction
of man hours in maintenance tasks does not mean that the
next logical step is to reduce the number of employees.
Another option for those managers who want to prepare
for the future is to implement a “Continuous
Improvement” billet. This alternative option for cost
reduction is “Corrective Maintenance Task Generation”.
Corrective Maintenance Task Generation is
best performed by the same personnel who perform
corrective maintenance. The normal technician’s time
schedule does not allow the time to document tasks in
detail. Some companies rely on the maintenance
supervisor to document and implement new preventative
and corrective maintenance tasks. Maintenance
supervisors are often too heavily tasked to make this
option feasible without risking lost productivity. In
addition, maintenance supervisors do not perform
corrective maintenance tasks on a regular basis.
Therefore, the process of remembering how to perform the
task can take longer and be incomplete. Detail is the
key to effective corrective maintenance tasks.
One solution to the manpower issue is to
maintain an extra technician for documenting corrective
maintenance tasks. Technicians can be rotated on a
periodic basis by area of expertise to document
corrective maintenance tasks, perform parts research,
and perform lock-out/tag-out verification for those
tasks. Corrective maintenance tasks can then be input
into the Computerized Maintenance Management System
(CMMS) or a database kept by the maintenance manager for
future use. Whenever a corrective maintenance task
needs to be performed, the technician can print a copy
of the work instruction detailing the procedure for
locking out equipment, parts needed, and how to perform
the task. This kind of corporate knowledge cannot be
easily passed person to person by word of mouth.
The benefits to the
corrective maintenance task generation can be seen in
many areas. The first benefit is that the time for
completion of common corrective maintenance tasks can be
reduced by a conservative estimate of 10%. For example,
a task that takes 30 minutes on a normal basis can be
reduced by 3 minutes.
For a production line that loses $60 for every minute it
is down, this can save $180. The task generation will
take about 3 hours at an estimated rate of $90 ($20 for
salary and $10 for benefits per hour). If the casualty
happens 5 times per year on average, the cost of lost
operation alone would be $9,000 ($60 per minute times 30
minutes times 5 incidents). With the detailed
maintenance task it would be $8,100 ($60 per minute
times 27 minutes times 5 incidents). The savings in the
first year would be $810 ($900 savings minus $90 for the
task generation). Over the long term, the cost savings
would more than pay for the extra technician. Alone,
this task may seem like a small savings, but combined
with other tasks the savings can soar. An example of
the corrective maintenance task is described in Table 1
with no written task compared to a written task on the
replacement of a hydraulic cylinder that is leaking.
The following comparison assumes that the system will
restart properly after the lockout is cleared. With no
written procedures, the system is less likely to restart
properly.
|
Written corrective maintenance task |
No
written corrective maintenance task |
|
1. Print
out corrective task. (3 min) |
1.
Lock-out system. (5 min) |
|
2.
Lock-out system. (4 min) |
2. Find
part number and retrieve part. (7 min) |
|
3.
Retrieve part. (3 min) |
3.
Replace cylinder. (15 min.) |
|
4.
Replace cylinder. (13 min) |
4. Clear
locks and restart system. (3 min) |
|
5. Clear
locks, restart system, and sign off corrective
maintenance task. (4 min) |
|
|
Total
time: 27 minutes |
Total
time: 30 minutes |
Table 1. Corrective
maintenance task.
The knowledge a
technician gains while performing the task writing
process will help prepare them for future positions in
supervisory or planning capacities. Technicians
normally spend very little time honing their
administrative skills in preparation to become
supervisors. Too many technicians become supervisors
that are not educated on the “behind the scenes” skills
and concentrate on shop floor direction instead of
growing their personnel. The better trained a
technician is, the easier it becomes to supervise and
manage them.
It is generally
accepted that a plant is a very stressful environment,
especially when the onus is on to get the plant running
again. Technicians can get a small break from the
reactive nature of the job. The morale benefits of the
“down time” can improve overall work atmosphere and in
turn the productivity of the personnel.
The safety of
performing tasks can be increased by having lock-out
lists and safety warnings with every task. When the
pressure is on to get equipment running, mistakes are
more likely to happen. The possible reduction of safety
hazards can alone be a large cost savings.
The level of detail
of the corrective maintenance tasks can be written to
the realignment of the equipment after the task. This
will increase the probability that when the system is
started back up the system will perform to
specifications.
The final and
probably most important benefit for the maintenance
manager is the building of a corporate expert system.
The building of an experienced and well-trained
workforce is expensive. Corporate expert systems can
build experience more quickly in new technicians than
can the “school of hard knocks.” Such learning from
mistakes can be costly.
Corrective maintenance task generation can
produce long-term cost reduction, especially when used
to implement the results of an RCM or BPR analysis. The
process can help move a maintenance department to the
next level and better prepare for the future.
Corrective maintenance task documentation can be used in
any system in conjunction with any other continuous
improvement plan. Most companies can perform this
process improvement plan in some fashion, even if only
on a periodic basis. In doing so, they will reap the
benefits of years of tribal knowledge.
Robert Apelgren is a Reliability Engineer. He received
his BS in Industrial Technology from Roger Williams
University and is currently working on an MBA at the
University of Phoenix. He is a Certified Maintenance
and Reliability Professional. He has 12 years of
maintenance experience as a technician, supervisor,
coordinator, consultant, and trainer. |