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Prepared
for and presented at IR/INFO
2001 By:
Terrence O'Hanlon
Introduction
Those who do not understand history are doomed to
repeat it! How many times has your advanced condition-monitoring
program uncovered the same failure? With the use of the latest
hardware and software, Infrared Thermographers have become very
proficient at detecting problems (hopefully before disaster
strikes). Unfortunately these technologies do very little in terms
of preventing the problem from occurring in the first place.
That is where “reliability” comes into play!
Reliability is defined as:
The probability that equipment or systems will
perform required functions satisfactorily under specific conditions
within a certain time period.
Failure is defined as:
The inability of the asset to do what the owner
wants it to do!
Get out of the maintenance business!
Your company is not in the maintenance business.
Your company exists in order to perform its process or to produce
its widget in order to meet as much of the demand as the physical
assets will allow!
You must be aware of the overall goals of the
company and align your program and goals with the company’s goals!
The First Law of Good Maintenance
"In maintenance, when you get really good at
something, you’re doing it much too often. There has to be a
better way, and it’s time to do a serious failure analysis,"
says a former maintenance manager and now a corporate executive.
According to Neville Sachs, a leading RCA
consultant, “Combining effective failure analysis with a good
predictive maintenance program usually results in huge benefits.
Depending on the type of facility, it can not only reduce
maintenance costs by 20 to 30 percent, but also increase production
by similar values. However, it does require a cultural change.
Four years after a failure analysis program was
started in a large heavy industrial plant, one of the mechanics
said, "The problem with this place is that there aren’t any
hero jobs anymore."
Most plant maintenance personnel derive job
satisfaction from solving problems. An effective RCFA program will
substantially reduce those problems, so alternative sources of job
satisfaction have to be found.”
Reliability Centered Maintenance (RCM)
RCM is a very tightly defined process, however
many people simply use the term to define the process of using root
cause analysis techniques to determine the specifics of a
maintenance program. We will not dwell on the debate as to the exact
meaning of RCM. We will focus on the basic underlying concepts that
are referred to as:
Reliability Centered Maintenance (RCM)
Planned Maintenance Optimization (PMO)
Root Cause Analysis (RCA)
Root Cause Failure Analysis (RCFA)
Mike Drew of ARMS
Reliability Engineers explains that a reliability-based
approach to Maintenance uses the probability of failure to select
the most effective maintenance strategy. The probability of failure
is determined either from past failures, knowledge and experience or
from industry references. Often it is found that existing record
systems and logs contain a wealth of data that has not been used to
predict future performance.
There as many reliability philosophies as there
are maintenance philosophies, however they all share some
commonality such as using various root cause analysis techniques to
discover the root causes of failures or potential problems. These
techniques are not only used to examine the physical aspects of a
problem, but also the human elements that may have an even larger
effect on the situation.
According to Charles Latino, founder and President
of the Reliability Center Inc.“When things go amiss, they are
caused by a multiplicity of errors. It is typical for eleven to
thirteen errors to occur prior to the one that obviously caused the
failure.”
Failure analysis techniques do not only focus on
what errors had occurred but also on why they occurred. Causes, such
as workers who are poorly prepared for their tasks, procedures that
are flawed (or do not exist), and workers who have too little time
to perform a task with precision, engineering errors and poor
communication. These are areas where management can exercise the
most control.
Many of the errors that occur or might of occurred
had your Infrared Inspection program not detected it, are caused by
the lack of time and attention devoted to problem/failure avoidance.
When equipment fails and shuts down the productive capacity of a
facility, often the plant manager will only ask when will it be
ready to run again. If he or she does this often enough they will
instill a paradigm in the workforce that says that management is not
interested in the quality of repairs, only in getting the process
running again. Management has now laid the seed for poor quality
work and they don’t even know it. Even worse, the lessons and
wisdom that could have resulted from a thorough investigation of the
failure is lost.
As Michael Drew states, “in today's environment
where companies have gone through corporate takeovers,
privatization, business process reengineering, and downsizing, the
positive impact of increased plant availabilities at lower
maintenance costs can have a significant impact on its
profitability.”
Applying reliability concepts can go along way
toward achieving such gains.
Reliability Resources
Neville Sachs, P.E., is President of Sachs,
Salvaterra & Associates, Inc. The consulting firm
specializes in improved plant and equipment reliability and
technical support services. Previously, Neville was Supervisor,
Reliability Engineering for AlliedSignal Corporation where he was
instrumental in developing one of the first large predictive
maintenance inspection programs in the nation. Mr. Sachs received
Bachelor of Engineering Degrees in both Mechanical and Chemical
Engineering from Stevens Institute of Technology.
The
Reliability Center Inc., offers a virtual library of
reliability related articles that are well indexed and easy to read.
They offer a free email newsletter and have a discussion board where
you can post questions.
A great article on changing your thought process
to include reliability as part of the maintenance philosophy is
available at the Aladon
Ltd. Web Site This information was written by Reliability
Centered Maintenance (RCM) guru John Moubray. He replaces 15 old
maxims with 15 new maxims to help us understand the RCM approach.
Aladon is a consulting company that offers RCM2, a specialized
version of Reliability Centered Maintenance.
A comprehensive directory of additional
reliability resources is published at Reliabilityweb.com. Click
here for the Online Directory Home Page |
