RMC NEWSLETTER Editor

Kim Kallstrom

kkallstr@utk.edu R e l i a b i l i t y & M a i n t a i n a b i l i t y C e n t e r T h e U n i v e r s i t y o f T e n n e s s e e “ w h e r e i n d u s t r y & a c a d e m i a m e e t "

November 2010

Volume 15, Issue 4

RMC Fall Meeting Showcases Best Practices

RMC Members gathered at the Knoxville Airport Hilton September 28-29th for the Fall Members’ Meeting. The RMC Advisory Board met on Tuesday morning, the 28th, to discuss RMC business, and the General Session kicked off at 1:00 pm. RMC Director, Tom Byerley, welcomed the membership and introduced the new members of the RMC. New members include: Okuma - America and Sabic Innovative Plastics. Bob Kral of Okuma - America gave a brief overview of the company for those who were unfamiliar with their business.

The first best practice presentation was by Bart Jones and Steve Pearson, who discussed the Arnold Engineering Development Center’s (AEDC) journey to excellence, highlighting what they have done to create a sustainable culture of reliability and safety. Josh Estep then shared how Alcoa manages their PdM practices. After a brief break, Dwain Coppenger (Y-12), Eddie Johnson (Eastman Chemical), Jim Humphries (Fluor), and Ron Moore (The RM Group) shared their thoughts during a panel discussion regarding the impacts of an aging workforce and the best strategies for dealing with this challenge. The attendees then enjoyed hospitality time by the hotel pool before being treated to a wonderful dinner. In addition to the great food, there was plenty of time for networking and catching up with old friends.

On Wednesday morning, attendees convened for breakfast and then Tom Byerley and the RMC staff shared the status of programs, including MARCON, the internship program, and Monash.

Tom then turned the microphone over to Ken Piety, from Azima, who discussed how Cloud Computing could be used to leverage PdM programs. Ken was followed by Wes Kasey (IRISS) who shared some humorous stories to highlight safety and best practices concerning thermography. Vlad Bacalu, of Advanced Technology Services, provided the group with the do’s and don’ts of utilizing maintenance contract services. After a short break, Dr. Rupy Sawhney, Head of the IIE Department at UT, introduced several initiatives to ensure that the IIE Department is relevant to the needs of industry. Dr. Sawhney was followed by Nick Vigder and Ken Pearson, two of our RMC interns, who shared the highlights of their summer positions with Setech and Y-12, respectively. After lunch, the meeting came to a close with a second panel discussion regarding which tools to use and in what order. Panel members included: Kathleen Tulevski (Energizer), Paul Casto (Meridium), Steve Buchanan (Schlumberger), and Al Weber (Ivara).

t

Director’s Corner 2

Assessing Health Degradation in Aircraft Generators

3

New RMC Members 5

MARCON ‘11 Registration 6

Lean + TPM...a Redundancy?

8

RMC Intern Report 11

Calendar of Events 12

Inside this issue:

Page 2

Director’s Corner

The Reliability Path—From Student to Professional The RMC has recently experienced two major positive events. First, the summer internships that 23 of our UT engineering students were privileged to serve this summer came to an end and the students returned to campus to continue the ―educational‖ part of their life experience. Second, the RMC Fall Members’ Meeting was held with another set of great experiences for the 53 folks that participated in part or all of the meeting.

One part of the RMC meeting had two of our interns, Nick Vigder and Ken Pearson, presenting on their unique experiences with Setech/Harley Davidson and B&W Y-12 respectively. The quality of these two young men and the quality of their experiences was simply outstanding. They strongly reinforced our existing knowledge that the RMC intern program is without equal or parallel.

Also, during the members meeting, we heard from several professionals, all very well representing their organizations, and the reliability and maintainability world. The ages and experiences spanned from Josh Estep, a young engineer with Alcoa, through some in the middle of their careers and on to some approaching … (let’s just say the term ―greybeards‖ applied). I noted that every one of the presenters had something of value to share – and every one of them was also a student of what the other presenters had to share. We were all on a journey – following a path that was being lit by others with knowledge and experience.

I truly believe that our RMC intern program is placing students on a path to excellence – giving them the education (academic classes), training (―boot camp‖), and experience (internships) to enter the professional workforce well prepared to march forward. And I truly believe our RMC meetings and our annual conference, MARCON, further map out the pathway to excellence and provide guidance and light through the sharing of best practices and experiences by our members and presenters.

I invite you to participate with us by taking part in our intern program, our semi-annual members meetings, and our annual conference, MARCON. In fact, MARCON 2011, which occurs February 28 – March 4, 2011, is themed ―Reliability and Maintainability: The Pathway to Excellence‖. Read about it and our excellent program and venue elsewhere in this newsletter and/or on our RMC website. Also, we have already started rounding up and interviewing prospective intern students for the 2011 summer intern program, so you should be getting us your intern requests – the sooner the better.

Reliability and maintainability is a journey – one without end if we are to seek excellence. It’s an amazing journey, sometimes difficult, occasionally blessed with low hanging fruit along the path, and always both challenging and rewarding. We and our RMC member organizations all come with different knowledge and experiences, with different challenges and resources, with different goals and strategies, but we all want to move forward toward excellence. And we always find that together, the path is easier and a whole lot more fun. Come join us on our journey!

Tom

Tom Byerley

Page 3

Assessing Health Degradation in Aircraft Generators By: Dr. Freeman Rufus and Dr. Nicholas Propes,

Global Technology Connection, Inc.

I. MOTIVATION Electrical and mechanical failures (such as bearing and winding failures) combine to cause premature failures of generators, which become a flight safety issue forcing the crew to land as soon as practical. Based on the Naval Aviation Logistics Data Analysis (NALDA), the generator is the largest degrader of the aircraft’s major electrical power system components in terms of Aviation Depot Level Repair (AVDLR) costs, mission aborts, and non-mission capable hours. Currently, diagnostic / prognostic technologies are not implemented for aircraft generators.

Our research presents a methodology including feature extraction and diagnostic algorithms to ultimately: a) differentiate between these failure modes and normal aircraft operational modes; and b) determine the degree of damage/degradation of a generator. Electrical signature analysis based features were developed to distinguish between healthy and degraded generators while taking into account their operating conditions.

II. FEATURE DESCRIPTION Figure 1 depicts the basic modules of the proposed aircraft health management system. The diagnostic and prognostic health management system architecture utilizes data-driven and physics-based algorithms and also provides inputs to a CBM module. The feature extraction unit takes raw sampled data from a generator and converts it to a form suitable for the diagnostic and prognostic modules. The diagnostician monitors continuously critical feature data and the prognosticator reports the remaining useful lifetime of the failing machine or component to the CBM module. The CBM module schedules the maintenance so that uptime is maximized and long-term maintenance costs are reduced.

The prognostic architecture is based on three constructs: 1) a static ―virtual sensor‖ that relates known measurements to material deterioration; 2) a predictor which attempts to project the current state of the damaged material, thus allowing the estimation of the material’s remaining useful lifetime (RUL); and 3) a Confidence Prediction Neural Network (CPNN) whose task is to assess the uncertainty in the RUL prediction.

Time and frequency domain features derived from raw sensor data have been developed to distinguish between healthy and common failure modes such as bearing failure. Two methods are used for amplitude demodulation of the 3-phase aircraft generator voltage and current signals: a) Hilbert transform and b) Space vector transform. Features used in estimating the

Fig. 1-Overall Architecture for Diagnostic/Prognostic Assessment of Aircraft Fig.2 -Applying ESA to Motor & Generator Systems

Page 4

generator degree of degradation are computed from these demodulated signals. Statistical margins based on the features are defined in order to denote the differences between range of healthy/low-hour generators and degraded/high-hour generators. These features are based upon Electrical Signature Analysis (ESA) concepts (Figure 2). ESA is the term used for the evaluation of the voltage and current waveforms. This provides an increased advantage to diagnostics as power-related, motor-related and load-related signals can be quickly compared. The main purpose of incorporating ESA in our work is the fact that ESA uses the generator as a transducer, allowing the user to evaluate the electrical and mechanical condition from the generated electrical signals.

The diagnostician, implemented as a multiple-input multiple-output fuzzy neural network (FNN), serves as a nonlinear discriminator to classify impending faults. The fault classifier is trained to recognize generator faults from a vector of features corresponding to rotor, stator and bearing failures. The virtual sensor calculates a failure measure indirectly through a neural network mapping of features and operating condition. Consider, for example, the case of an electrical generator. No direct measurement of the degree of stator / rotor winding degradation, bearings damage, etc. occurring in a generator is currently available when it is in an operational state. That is, there is no such device as a ―fault meter‖ capable of providing direct measurements of the fault evolution. The fault dimensions take the form of a vector of integer state-of-health (SOH) values where the values range from 100 (healthy) to 0 (fault). A sample SOH is depicted in Figure 4, below.

Generator Classification and Health Estimation Example: NAVAIR provided electrical (voltage and current) data collected at 100 kHz for five P-3 generators (Gen 73-A0255, Gen 1182, Gen 18700071, Gen 700 and Gen 765). The data was collected for the following resistive loads and operating frequency: a). no load, 30 kVA and 60 kVA; b). operating line frequencies of 395Hz, 400 Hz and 405 Hz.

As shown in Figure 3, the brand new generator has less range between the minimum and maximum values of the demodulated signal than Gen 1182. Therefore, the following two general features were selected to detect degradations in P-3 generators:

|P(t)|max diff = [|P(t)|max – |P(t)|min] per phase angle bin |P(t)|mean = (1/N)×Σ |P(t)| per phase angle bin

The diagnostic algorithms were developed to have a low false alarm rate. The feature extraction and diagnostic algorithms were evaluated against P-3 generator data (phase

Fig. 3- Demodulated voltage signals as a function of phase angle Fig. 4- SOH of P-3 Generators

Page 5

operating line frequencies for healthy, low-hour and high-hour generators). The results show that the electrical signature analysis of the generator’s phase voltage(s) can be used to assess and predict its health.

III. CONCLUSION Time-domain features based upon ESA were developed to distinguish between healthy/low-hour and degraded/high-hour P-3 generators. The detection rate for degraded/high-hour P-3 generators was greater than 99% with less than 0.2% false alarm rate. The brand new P-3 generator was correctly identified as being healthy for more than 99% of the analysis windows. This testifies to the accuracy of the model and the analysis on it. The resulting degradation measure would translate to advantages such as prevention of aircraft loss due to generator failure, a maintenance scheduling strategy that is condition based, readiness evaluation of aircraft fleets, reduced down-time, etc. Global Technology Connection, Inc. (GTC) develops technology tools for Condition-based Maintenance (CBM) that can substantially reduce the maintenance cost and increase uptime. These tools can prevent failures in a variety of equipment and machinery like HVAC, ground vehicles, power turbines, etc. GTC also works with OEMs to make technology tools that can be embedded into the new equipment sold in the market.

WELCOME NEW RMC MEMBERS!!!

MARK YOUR

CALENDARS!!

Feb. 28 - Mar.4, 2011

MARCON 2011

————

Jun. 7 - 8, 2011

RMC 2011 Spring Meeting

Advance Your Career and Your Company with Monash Programs

Maintenance & Reliability Engineering and Asset Management have become powerful tools in improving industrial profitability.

Demand for skilled professionals and managers with education in advanced technologies and certification in these fields continues to increase.

Since 1985, hundreds of engineers, managers and senior technical people worldwide have increased their skills and capability by completing Monash courses in the fields.

Register by Dec. 31st

for 2011 Master’s Degree & Program

Visit www.RMC.utk.edu for full course catalog

Page 6

Page 7

Page 8

Lean + TPM…a Redundancy?

by: Enrique Mora

Not necessarily! By the 1960’s, Preventive Maintenance (PM), was the buzz word. It came along with many costly recommendations, and in many cases it keeps generating unnecessary cost in parts, downtime, and workmanship. Replacements based on the calendar can be destructive to your budget and efficiency.

Then Nippondenso in Japan, a First Tier Toyota supplier, introduced TPM in the 1970s, which was immediately adopted by the Toyota Production System. This strategy gets everyone in the organization to think of ―Maintaining Productivity‖ as one of their key responsibilities, which it really is.

TPM though has been considered by some as ―the ugly duckling‖ of Lean Manufacturing because in the traditional manufacturing operations, maintenance was considered as a ―necessary evil‖. Not so—the new vision with Lean Manufacturing attributes more importance to this activity so that equipment is kept at optimal performance. We definitely should consider TPM as an essential strategy of the Lean Culture which focuses on moving the product expediciously and efficiently through the process. This reduces all kinds of wastes.

In my opinion, TPM is a very logical evolution of PM, with the advantage of raising the awareness that we all can and should participate to keep the productive capacity of our plant, since we all benefit from the increased reliability of the equipment. TPM helps keep the equipment running, thus allowing the process to take place at the right time. This involvement of everyone, including of course the operators’ ownership of the equipment, is called Autonomous Maintenance, the cornerstone of TPM. Although many ―Lean Companies‖ have heard about or even attempted Autonomous Maintenance, many have not yet discovered its full importance and benefits.

Preventive Maintenance stays in place as one of the integral parts of TPM. It is the indispensable process, within the TPM strategy, that cares for preserving the machine in optimal condition, preventing break-downs. Now the challenge is to Optimize Preventive Maintenance.

Page 9

PM Optimization

PM Optimization urgently needs to be implemented these days. It is the logical partner of RCM [Reliability Centered Maintenance]. Organizations with an ARIPs [Asset Reliability Improvement Program] in place also validate the importance of the PM Optimization tasks which provide substantial savings over the traditional PMs. Good PMs will in turn generate Scheduled Corrective Maintenance thus reducing Emergency Corrective Maintenance to as low as <3% of the maintenance activity. The following is an example of what was achieved at a construction company in the Midwest and represents what we can expect from PM Optimization:

In the 1960s Preventive Maintenance was focused on ―just in case‖ replacements that did not necessarily increase reliability. Still today, some biotech and food plants, as well as other ―traditional‖ facilities, still make expensive replacements because there is not enough information on the real ―working-time‖ or internal condition of some pieces of equipment. Also, there are still many PM orders to ―review‖ or ―observe‖ which can most likely be removed. With the excellent technology and tools that are available today, we can do a better and easier job. Vibration analysis, for example, can help determine the status of a bearing while in operation.

Optimizing the PM orders can also be achieved by listening to our technicians. We can discover a good number of improvements which will translate into a higher Maintainability by lowering the MTTR [Mean Time to Repair] and MTTV [Mean Time to Verify]. One key aspect to take care of is to provide clear and understandable wording of these PM orders so that they can be assigned to educated operators and other customers within the implementation of Autonomous Maintenance, the core discipline of TPM.

Among the many maintenance simplifications I have seen through the years these are some issues and actions taken:

Sliding covers (with lifting handles to ease removal and reinstallation), which stay in

place by gravity, some (if really needed), with the help of simple safety latches or a single wing-nut, eliminating plant-wide, hundreds or thousands of bolts and minutes

required for their removal and re-installation.

Railed filter guides or pre-framed filter elements which eliminate the use of unneeded removable frames and make filter change a 1-second (instead of several minutes) operation. Also some Velcro applications are practical in some cases.

Gravity-closed access doors to belt covers so tension can be verified. (Make sure there

is a warning when equipment is in operation.) These belt transmission covers should also have at least one of the sides made of screen (painted in black) so belts can be seen through it.

Year PM as % of the

Maintenance Activity

Scheduled Corrective

Maintenance

Emergency Corrective

Maintenance

2000 11% 24% 65%

2004 40% 49% 11%

2006 38% 45% 17%

2009 48% 46% 6%

2010 57% 40% 3%

The focus is to bring down the Emergency Corrective Maintenance which

represents production stoppages. This reduction applies directly to the

Cost of Operation. As we can see, it was brought from 65% to 3%!

Page 10

Remote lubrication points and fluid level indicators put in places accessible to the

operator.

Visual systems need constant improvements and updating to make them more user-friendly and more helpful all the time…

Make them more graphic and less wordy.

Use real pictures to show tasks.

Have persons (operators) appear in the pictures.

On rotating equipment, show the coupling, seals, and bearing numbers clearly on the covers, as well as the correct rotation.

Clearly create awareness for safety issues and good practices.

Oil and other fluids’ filters should all have pressure-delta warnings, so they tell the

operators and technicians when they need to be cleaned or replaced.

Screw-sliding bases for motors help avoid the need for realignment and also will ease the

replacement of seals, belts, chains, pulleys, and sprockets.

Of course, these are just a small sample. Your maintenance crew and the operators who get involved in the Autonomous Maintenance will come up with more and better ideas. Listen to them! Do not underestimate their creativity and intelligence.

Lean-TPM is, of course, a never-ending process. Just as the physicians and attorneys must keep up to date to be effective, maintainers also have that responsibility. We are living in a high speed era of technological improvement. Live it and enjoy it.

In summary, Lean – TPM is about making sure we find better ways all the time to increase the Reliability and Maintainability, as well as the self-esteem of the participants. As a long time practitioner of these techniques, I feel qualified to recommend that you make sure that the meaning of TPM in your facility is:

―The Commitment of Everyone to

Improve and Preserve the Productivity of the Plant.‖

TPM is not a chore. It is a privilege to be a part of it. Make sure the pride is shared by everyone as well.

Perhaps the above paragraph contains the essence of successful implementation. There is always room for improvement and all the participants must believe that we are there to pay attention to their ideas. Lean and TPM go hand in hand to truly increase the productivity of your plant!

Enrique Mora has been implementing: PM, TPM, SMED, Management Through Leadership, and many other strategies for the last 40+ years and keeps important volumes of information in both English and Spanish at his websites: www.ManagementThroughLeadership.com, www.TPMonLine.com, and www.LeanExpertise.com among others. Toll-Free Phone: 866-611 MORA (6672)

Page 11

2010 Intern Report

This past summer, twenty-three University of Tennessee (UT) Engineering students had the opportunity to intern with ten of our RMC member companies. All of the students learned an incredible amount from their on-the-job experiences, while providing the companies with temporary assistance with projects. The companies also had the opportunity to observe some of UT’s finest for the summer. Below is an end-of-summer report by one of the student interns, detailing the projects he worked on while on the job.

MIKE HAWKINS—SCHLUMBERGER

My internship with Schlumberger was one of the best internships I have had, mainly because of the tools that were used and the experience gained. The internship was a maintainability-specific project relating to one of Schlumberger’s newest technologies in oil well sampling. The main scope of the project was to determine a metric for a drill used to extract earth cores from deep within the well.

Upon arrival it was very obvious the interns had an important role within the company. All of the interns had very important projects pertaining to complex engineering situations. Soon after settling in and completing the required training courses, I was given a FMEA that detailed the tool I would be working on. The FMEA was the first step in determining how I would steer my project throughout the summer. The FMEA showed that a hydraulic motor used to power the drill to extract the cores had a high severity level, which indicated that if this part failed, the whole tool would need extensive maintenance. That indicated that there was a need to know when that motor needed maintenance which introduced the concept of maintenance signaling. From there, I designed a test fixture to simulate the motor drilling cores until failure, taking measurements such as pressure, flow rate, torque and speed. Once the motor failed, I was able to look at different measurements taken that would tell the operators which motor needed maintenance. I specifically looked at the ratio between the speed of the electric motor supplying the fluid power to the speed of the motor output. This ratio in conjunction with the pressure showed a decrease in mechanical and volumetric efficiency. This was the first sign indicating that a motor was going bad.

The experience gained throughout my internship will follow me throughout my career. The engineering tools used for the project increased my confidence for post graduation to be able to use the knowledge gained during my collegiate career. The people that I worked with on an everyday basis were very helpful and showed more respect than I had expected. By the end of the summer I had completed my project and felt that I had improved their process. I would recommend an internship with Schlumberger to any of my engineering peers, but warn them to be ready to utilize those skills taught in the classroom.

The University of Tennessee does not discriminate on the basis of

race, sex, color, religion, national origin, age, handicap, or veteran

status in provision of educational opportunities or employment opportunities and benefits. UT does not discriminate on the basis

of sex or handicap in its educational programs and activities

pursuant to requirements of Title IX of the Education Amendments of 1972, Public Law 92-318; and Section 504 of the

Rehabilitation Act of 1973, Public Law 93-112; and the

Americans with Disabilities Act of 1990, Public Law 101-336, respectively. This policy extends to both employment by and

admission to the University. Inquiries concerning Title IX,

Section 504, and the Americans with Disabilities Act of 1990 should be directed to the Office of Affirmative Action; 403-C

Andy Holt Tower, The University of Tennessee, Knoxville, TN

37996-0144; (865) 974-2498. Charges of violation of the above policy also should be directed to the Office of Affirmative Action.

IF YOU NO LONGER WISH TO RECEIVE MAILINGS FROM THE RMC, KINDLY PHONE, EMAIL OR MAIL US YOUR ADDRESS LABEL AND WE WILL REMOVE YOUR NAME FROM OUR MAILING LIST.

RMC Calendar of Events

Nov. 9-11 Solutions 2.0 (Bonita Springs, FL)

Dec 31 Monash Application Deadline

Feb 28-Mar 4 MARCON 2011 (Knoxville, TN)

May 9-13 Overview of Modern R&M Concepts / Intern Bootcamp (Knoxville, TN)

May 10-12 MFPT 2011 (Virginia Beach, VA)

June 7-8 RMC Spring Members’ Meeting (Knoxville, TN)

Reliability & Maintainability Center The University of Tennessee “where industry & academia meet"

Reliability and Maintainability Center University of Tennessee 506 East Stadium Hall Knoxville, TN 37996-0750

Phone: 865-974-9625 Fax: 865-974-4995 Email: Center - RMC@utk.edu Tom - tbyerley@utk.edu Klaus - kblache@utk.edu Robbyn - rcollin8@utk.edu Kim - kkallstr@utk.edu

We’re on the Web! www.RMC.utk.edu

Reliability & Maintainability Center The University of Tennessee “where industry & academia meet"

Reliability and Maintainability Center University of Tennessee 506 East Stadium Hall Knoxville, TN 37996-0750

Editor’s Note: This newsletter contains articles contributed by various individuals not part of the RMC staff, and which do not necessarily reflect the opinions or understandings of the RMC staff. Comments and reflections on these articles and/or any part of the RMC newsletter are welcome.