OCTOBER 2014
NIPSCO ENERGY SYMPOSIUM
MANAGING ELECTRIC
MOTORS FOR RELIABLE
SERVICE
Presented by: Todd A. Hatfield and Mark S.
Hatfield of:
HECO Inc. Industrial Service Groups of
Kalamazoo Michigan
HECO Introduction
Who is HECO?
HECO is an Electric Motors & Performance Systems
Company
We specialize in custom systems
That optimize the performance of
Electric motor driven powertrains.
How do we do this?
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Electric Motor & Generator Repair
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Specification based Procurement from fractional through 15,000HP+
Mfg’s such as ABB/Baldor, Siemens, TECO-WH, WEG, GE, Etc.
Predictive Services
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110v AC through 13,800v AC & Up to 750v DC
Electric Motor & Control Sales
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Repair, Engineering, & Testing from ¼ HP through 25,000+ HP
ISO Certified Vibration Analysts (through Cat IV), Tribology, Thermography,
Ultrasonic Analysis, Wireless Condition Monitoring
Electric Motor Control Services
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Control Retrofitting, DC to AC Conversions, VFD Programming & Start-Up,
Control Troubleshooting, etc.
History
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HECO was founded in 1959
Started first Motor Management Program in 1984 with Kalamazoo, MI area
General Motors plants.
From 1968 to 1992 we grew from a 8,125 Sq. Ft facility to the present 65,000
Sq. Ft.
Opened our 176,000 Sq. Ft Warehouse in Hammond, IN in 1995
In 2013 we acquired Predictive Maintenance Services Inc. and Formed HECO
Predictive Service Group.
Testing a 4000hp, 4000V Siemens motor on
our 13.8kv, 4000KVA, 100 ton weight limit
test stand
Machining the shaft on a 9000HP
remanufactured rotor on our 79”
Swing x 20’ long lathe
Balancing a 1750KW Armature on our
30,000lbs computerized dynamic balance
stand
Moving a 3000HP, 514RPM
Vertical Motor after assembly
Lifting a 13.8kV Generator off of our truck
for repair
Electrical testing re-built field
frames
Unloading 3 Hydro-Generators for complete
remanufacturing
Loading a 1250KW armature into our 17’
tall curing/bake oven
Introduction to: Managing Electric
Motors for Reliable Service
In this seminar we will discuss the “industry
workhorse”, the AC Induction Motor; and how it
works; the various component parts and how these
components can vary in design and shape to produce
a multitude of specific designs that work for a variety
of applications. We will also talk about operating
abuse and what to avoid to improve reliability.
Finally, we will discuss a systematic 12 step approach
to Managing Electric Motors for Reliable Service.
How an AC
Induction Motor
works
Basic AC Motor
Operation
An AC motor has two basic electrical
parts: a "stator" and a "rotor“. The
stator is in the stationary electrical
part. It consists of a group of individual
electromagnetic coils arranged in such
a way that they form a hollow cylinder.
The term, "stator" is derived from the
word stationary.
The rotor is the rotating electrical
component. It consists of a group of
electro-magnets arranged around a
cylinder. The rotor, is located inside
the stator and is mounted on the motor's
shaft. The term "rotor" is derived from
the word rotating.
The objective is to make the rotor
rotate which in turn will rotate the
motor shaft. This rotation occurs
because unlike magnetic poles attract
to each other and like poles repel.
Basic electrical components of an AC motor.
If we progressively change the
polarity of the stator poles in such a
way that their combined magnetic
field rotates, then the rotor will follow
and rotate with the magnetic field of
the stator.
Alternating Current - AC
The concept of alternating current came from Nichola Tesla back in the late
1800’s. The concept was to have current flowing in one direction through the
conductor and then in the other direction. By doing this, you would have a
positive (+) direction half the time and a negative (-) direction the other half.
In the U.S.A. the current flow will repeat the positive and negative cycle 60
times per second. This 60 cycles per second is the frequency at which power
is produced. One cycle per second is equal to one Hertz. Note: The strength of the
magnetic field produced by an AC electro-magnetic coil increases and decreases with the increase and
decrease of this alternating current flow.
Visualization
of AC.
Current can be dangerous!
Faradays Law of
Electromagnetic Induction
Three things must be present in order to produce
electrical current:
1. Magnetic field
2. Conductor
3. Relative motion
Conductor cuts lines of magnetic flux, a voltage is
induced in the conductor
This “rotating magnetic field” of the stator can be better
understood by examining the Figure below. As shown, the
stator has six magnetic poles and the rotor has two poles. At
time 1, stator poles A-1 and C-2 are north poles and the
opposite poles, A-2 and C-1, are south poles. The S-pole of the
rotor is attracted by the two N-poles of the stator and the Npole of the rotor is attracted by the two south poles of the stator.
At time 2, the polarity of the stator poles is
changed so that now C-2 and B-1 are N-poles
and C-1 and B-2 are S-poles. The rotor then is
forced to rotate 60 degrees to line up with the
stator poles as shown.
At time 3, B-1 and A-2 are N. At time 4, A-2 and C-1 are
N. As each change is made, the poles of the rotor are
attracted by the opposite poles on the stator. Thus, as the
magnetic field of the stator rotates, the rotor is forced to
rotate with it.
Three Phase Power
3 phase AC generators produce three separate current flows (phases) all superimposed on
the same circuit. This is referred to as three-phase power. At any one instant, however, the
direction and intensity of each separate current flow are not the same as the other phases.
(This is illustrated in the Figure below. The three separate phases (current flows) are labeled A, B and C.)
A complete cycle takes one complete revolution of the generator or 360 electrical degrees.
Note: each phase is displaced 120 degrees from the other two phases or 120 degrees out of
phase.
The
pattern of
the
separate
phases of
threephase
power.
A
B
C
“Rotating Magnetic Field” conceived by Nichola Tesla
The basis for the three phase induction motor
The basic Induction motor
How
voltage is
induced in
the rotor,
resulting in
current flow
in the rotor
bars.
Motor Construction
Three Phase Motor Construction
Windings – Electromagnets
Rotor bars
Rotor
Stator
Stator
Windings
Enclosure
Air Gap
Stator
Rotor
Side View
AC Motor Components
Two Basic Parts of any AC Motor
•
•
Stator contains
windings mounted in
frame of
motor
Rotor and
Shaft rotating unit
mounted on
bearings and
provides
mechanical
power
Stator
Rotor
Shaft
Rotors
Rotor
With an induction motor’s rotor, there is no connection to the power supply. As its name
implies the rotor rotates from Induction resulting from the magnetic field of
the stator. This induction is a natural phenomenon which happens when a conductor
(aluminum or copper alloy) is moved through a magnetic field or when a magnetic field is
moved past the conductor/bar.
Construction of an
AC induction rotor.
ROTOR DESIGN - Cast vs. Bar
Cast Rotor
• Rotor Bars in Intimate Contact With
Laminations (Excellent Heat Dissipation)
• Wide Variety of Slot Shapes Possible for
Various Speed/Torque Characteristics
Bar Rotor
• Rugged Construction
• Repairable
• Different Alloys , Different Speed/Torque
Characteristics
ROTOR DESIGNS
Aluminum
Rotor
Copper Alloy
Rotor
Common types of aluminum rotors
Common types of Copper alloy rotors
Copper alloy rotor
Fabricating a spider shaft assembly
Bars are tightly inserted
Bar Rotor
Construction Steps
Rotor slot shapes
Stacked Rotor Laminations
Bar Rotor
Construction Steps
Comparison of Cast Al vs. Cu Bar Rotors
Characteristic:
Cast Al
CuBar
Manufacturing Costs
Low cost to build each
High Tooling cost
55% only
High cost to build each
Low Tooling cost
100% to 5%
Good
Inertia of rotor
Excellent (3X heat
transfer)
Low (20-30% lower)
Size limitations
Up to 5812 Frame
5000 Frame and up
Casting PorosityPotential
Repairable
Yes
No
No
Yes
Conductivity
Starting ability
Good
Stators
Stators
Laminated stator cores before rewinding
GE 3500 HP Stator with windings
Allis
Chalmers
10,000 HP
Stator
STATOR
WINDINGS
Form Wound
Siemens 4000HP
Stator being rewound
LOWER VOLTAGE
STATOR WINDINGS
Random Wound
Questions?
We all need a SHORT vacation sometimes!
Bearing Selection
Motor bearings are selected based on application
requirements:
 Load
Speed
 Temperature
 Environment
Motor Bearing Types
Depending on size, rotational speed, load, and other application
requirements,
(3) basic bearing designs are used:
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Anti-friction (Ball, Roller, etc):
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Used in large horsepower based on application
Journal/Sleeve:
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Primarily used in NEMA size (integral horsepower)
motors
Used exclusively in medium to Large horsepower motors
Tilting Pad (Kingsbury):
•
Used exclusively in large vertical motors
Anti Friction Bearing Advantages
Relatively low cost
Simple design
With stand long periods of non-use
Multiple motor mounting positions
Good for radial and axial loads
Replacements easily obtained from multiple
sources
And Disadvantages
Speed and shaft diameter limited
Requires periodic re-lubrication
Replacing bearings requires major motor
disassembly
Bearing life limited due to fatigue
Ball Bearing Components
Basically, all bearings consist of 4 parts:
1. Inner Ring/Race
2. Outer Ring/Race
3. Rolling Element
4. Retainer
Understanding Motor Nameplates
What the information really means
Detailed Nameplate Information
•
The nameplate of a motor provides important information
necessary for selection and application.
Voltage and Amps
AC motors are
designed to operate
at standard
voltages and
frequencies. This
motor is designed
for use on 460 VAC
systems. Full-load
current for this
motor is 34.9 amps.
Nameplates continued
RPM
•
The nameplate speed
(RPM), is where the motor
develops rated horsepower
at rated voltage and
frequency. The base speed
of this motor is 1765 RPM at
60 Hz. The synchronous
speed of a 4-pole motor is
1800 RPM (@ 60 Hz). When
fully loaded there will be
1.9% slip. If the connected
equipment is operating at
less than full load, the
output speed (RPM) will be
greater than nameplate.
RPM = 120 x Hertz = 120 x 60 = 1800 rpm
poles
4
% slip = Sync RPM – Full load RPM X 100
Sync RPM
Motor Operating Speeds
At 60 HZ
At 50 HZ
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# OF
POLES
SYNCHRONOUS
SPEED (RPM)
FULL LOAD
SPEED(RPM)
2
3600
3550
4
1800
1750
6
1200
1150
# OF
POLES
SYNCHRONOUS
SPEED (RPM)
FULL LOAD
SPEED(RPM)
2
3000
2958
4
1500
1458
6
1000
958
Mechanical speed tied to speed of rotating magnetic field in stator
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Synchronous Speed = 120 x Frequency/# Poles = (@ 60 Hz) 7200/# poles
Rotor lags behind - difference called “Slip”
“What is Slip?”
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To produce torque in an induction motor, current must
flow in the rotor.
To produce current flow in the rotor, the rotor speed must
be slightly slower than the synchronous speed.
The difference between the synchronous speed and the
rotor speed (rated speed) is called the slip.
Flux
Stator
Slip
Rotor
Nameplate continued
•
Service Factor
A motor designed to operate at
its nameplate horsepower rating
has a service factor of 1.0. This
means the motor can operate at
100% of its rated horsepower.
Some applications may require
a motor to exceed the rated
horsepower. In these cases a
motor with a service factor of
1.15 can be specified. The
service factor is a multiplier that
may be applied to the rated
power. A 1.15 service factor
motor can be operated 15%
higher than the motor’s
nameplate horsepower. The 30
HP motor with a 1.15 service
factor, for example can be
operated at 34.5 HP.
• It should be noted that any motor operating
continuously at a service factor greater than
1 will have a reduced life expectancy
compared to operating it at it’s rated
horsepower. In addition, performance
characteristics, such as full load RPM and
full load current, will be affected.
Nameplate continued
•
Class Insulation
The National Electrical
Manufacturers Association
(NEMA) has established
insulation classes to meet
motor temperature
requirements found in
different operating
environments. The four
insulation classes are A, B, F,
and H. Class F is commonly
used. Class A is seldom used.
Before a motor is started, its
windings are at the
temperature of the
surrounding air. This is known
as ambient temperature.
NEMA has standardized on
an ambient temperature of
40° C, or 104° F within a
defined altitude range for all
motor classes.
Nameplate continued
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Temperature will rise in the motor as soon as it is started.
Each insulation class has a specified allowable temperature
rise. The combination of ambient temperature and allowed
temperature rise equals the maximum winding
temperature in a motor.
A motor with Class F insulation, for example, has a
maximum temperature rise of 105° C when operated at a
1.0 service factor. The maximum winding temperature is
145° C (40° ambient plus 105° rise). A margin is allowed to
provide for a point at the center of the motor’s windings
where the temperature is higher. This is referred to as the
motor’s hot spot.
The larger the temperature gap is between actual motor operating temperature
and the motor insulation class, the longer the insulation life will be.
Nameplate Continued
•
The operating temperature of a motor is important to
efficient operation and long life. Operating a motor above
the limits of the insulation class reduces the motor’s life
expectancy. A 10° C increase in the operating temperature
can decrease the motor’s insulation life expectancy as
much as 50%.
Ambient
Most of the time, the ambient consists of the heat generated by the heating and
cooling system around the motor (this would include changes in the weather).
Many times there are other heat sources close to the motor that will have an
effect on the surrounding ambient.
These sources can include:
1. The bearing temperatures and lubrication system
2. Running the motor in a confined space without proper ventilation
3. Poor positioning of air duct openings such as weather protected motors
4. Coupling and belt losses
5. Heat from the driven equipment, piping, plumbing, and other machines in the
area
This table shows the effects to the
insulation life when the allowed
temperature rise of the stator
windings is exceeded.
Nameplate continued
•
Motor Design
The National
Electrical
Manufacturers
Association (NEMA)
has established
standards for motor
construction and
performance.
NEMA design B
motors are most
commonly used.
• Efficiency --- AC motor efficiency is expressed as a percentage. It is an indication of how
much input electrical energy is converted to output mechanical energy. The nominal
efficiency of this motor is 93.6%. The higher the percentage the more efficiently the motor
converts the incoming electrical power to mechanical horsepower. A 30 HP motor with a
93.6% efficiency would consume less energy than a 30 HP motor with an efficiency rating
of 83%. This can mean a significant savings in energy cost. Lower operating temperature,
longer life, and lower noise levels are typical benefits of high efficiency motors.
Nameplate continued
Locked-Rotor kVA code
Letter (L.R. KVA Code)
A NEMA code letter (from A-V)
which defines the Locked-Rotor
kVA per-HP basis. This is used
by the installer to determine
the proper circuit protection
rating. Replacing a motor with
a higher locked rotor code may
require additional electrical
control equipment to handle
the higher inrush currents.
NOTE:
It is important to
pay attention to
NEMA code
letters, As the
letter goes up
the inrush
current
increases for a
given design
Efficiency
AC motor efficiency is expressed as a percentage. It is an
indication of how much input electrical energy is converted to
output mechanical energy
Motor-driven equipment “consumes” a
certain percentage of power when
driving a given load.
This is defined as “Watt Losses”.
Watt Losses
Input Power
(Watts)
Load
A-C Motor
(Some power lost
During conversion)
(Output power
1 HP = 746 Watts)
Calculation of energy efficiency
Efficiency = (0.746 x HP Output )
KWatts Input
= Input - Losses
Input
OPERATING CHARACTRISTICS
Motor Electrical Characteristics
• Torque Curves
• NEMA Designs
• Starting
• Supply voltage considerations
Typical Speed vs. Torque Curve
Motor torque is defined at four points on a motor
“Speed vs. Torque” curve and are:
Definitions of Motor Torques
¼ Horsepower?
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•
•
•
Locked-rotor Torque of a motor is the minimum torque,
which it will develop at rest for all angular positions of the
rotor, with rated voltage applied at rated frequency.
Pull-up Torque (Accelerating Torque) of an alternatingcurrent motor is the minimum torque developed by the
motor during the period of acceleration from rest to the
speed at which breakdown torque occurs. (CAN BECOME
CRITICAL IN STARTING APPLICATIONS)
Breakdown torque of a motor is the maximum torque
which it will develop with rated voltage applied at rated
frequency, without an abrupt drop in speed.
Full-load torque of a motor is the torque necessary to
produce its rated horsepower at full-load speed.
Motor Designs
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•
The Material and Shape of the Rotor Bars Are the Main Factors in
Obtaining Various Speed/Torque Curves
NEMA Defines 4 Basic Types of Speed/Torque Characteristics for Induction
Motors:
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DESIGN A
DESIGN B
DESIGN C
DESIGN D
The Stator Has Little to Do With the Shape of the Motors Speed vs. Torque
Curve - Different Rotors Can Be Used With the Same Stator to Change the
Characteristic Shape.
Note: This only applies to NEMA frame motors, above NEMA frames,
Induction motors are designed for the application and can have a variety of
torque characteristics that are unique and not standardized.
Comparison of NEMA Designs
NEMA Design Characteristics
Motor Starting Inrush Currents
•
•
Locked Rotor
Current typically
600-800% of full
load
Current and torque
aren’t linear until
near full load
Never start a motor too quickly!
Motor Starting Considerations
•
The motor torque vs. speed curve is usually provided at rated voltage. The torque and current of
the motor will change with voltage. The relationship between torque and voltage is as follows:
Torque  Voltage2
•
If voltage at the motor terminals is low, the torque produced by the motor will drop by
approximately the square of the voltage. Therefore, a motor with 90% rated voltage at the
terminals will have about 81% of peak torque. Since the motor has lower torque, acceleration
time will increase. If the torque of the motor drops such that it is not greater than the torque
required to accelerate the load, the motor will not reach rated speed.
Current  Voltage
•
•
The current of the motor drops proportional to voltage. Therefore, a motor with 90% rated
voltage has current reduced approximately 10% throughout the speed range.
The acceleration time of the motor is dependent on many factors. The motor torque and inertia
as well as the load torque vs. speed curve and inertia have to be known to determine acceleration
time. The acceleration time of a motor can be calculated using the following equation.
Acceleration Time = (WK²M + WK²L) x RPM
308 x Avg Accelerating Torque
RPM = Change in speed in rpm.
Average acceleration torque in lb.-ft. = (Average motor torque less
average load torque from minimum to maximum speed)
WHY CARE?
•
•
•
Motor could reach a stall
condition
Length of start time can
exceed hot or cold start
motor thermal limits and
crack end ring brazing
Could have been avoided
with 80% voltage torque
curve information
Stall
Condition
THINGS THAT IMPACT
MOTOR LIFE
Examples of load differences
The same motor but with a load
that requires a higher pull up or
accelerating torque…. This
would cause a stall condition.
The same motor but with a
load that does not require
higher torques to obtain full
speed.
Supply Voltage Considerations
•
•
•
Over voltage or
under voltage can
cause motors to
draw more current
Effect of voltage
change
Operating
characteristic
90% voltage
110% voltage
120% voltage
torque
Decrease 19%
Increase 21%
Increase 44%
Synchronous speed
No change
No change
No change
Percent slip
Increase 23%
Decrease 17%
Decrease 30%
Full-load speed
Decrease 1%
Increase 1%
Increase 1%
Starting current
Decrease 10-12%
Increase 10-12%
Increase 25%
Magnetic noise, any
load
Decrease slightly
Increase slightly
Noticeable increase
Starting and
maximum running
NEMA standards
allow + or - 10%
voltage variation
without degrading
the life of the
motor
Frequency can
vary + or - 5%
without degrading
the life of the
motor per NEMA
standards
Phase Balance Example
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Phase Unbalance = 3%
Temp. Increase = 2 (3)2
Temp. Increase = 18%
A motor normally operating with a
750 C. rise will see an 18% increase in operating temperature.
(75 x 1.18 = 850 C.)
With 3% voltage unbalance, a motor can produce 90% of its rated
horsepower without overheating.
Operation of a motor when the unbalance exceeds 5% is not recommended.
When unbalanced voltages exceed 5%, the temperature rise is so fast that
protection by de-rating is not practical.
Voltage phase unbalance is the most difficult to detect and therefore, often overlooked.
Motor failures caused by voltage unbalance and are often misdiagnosed as being damaged
by phase loss.
What can happen when left undetected
Voltage Unbalance = 236 – 228 X 100 = 3.5%
228
Temperature increase = 2x(Phase unbalance)² = 2(3.5)² =
This will lead to a overheated phase and
winding failure
24.5% increase in winding temp
Phase Voltage Unbalance
•
•
•
Slight unbalance =
large temp. rise.
High current phase:
% increased temp. =
2 (% voltage
unbalance)2
•
•
NEMA recommends
voltage unbalance
not exceed 1%.
Current unbalance
will be 6 to 10 times
voltage unbalance.
High/Low Line Voltage
•
•
Motors are
designed to
operate on a
balanced voltage
+/- 10% of
nameplate voltage.
Voltage variations
have the effect of
changing a motor’s
rating by the
square of the
voltage variation.
High/Low Line Voltage
High/Low Voltage Example
• A 10 hp. Motor operating with line voltage
10% below nameplate will have 8 hp.
characteristics.
• (90%)2 / 100 = 81%
• 10 hp x .81 = 8 hp.
• The motor will overheat trying to produce
10 hp.
Motor Life
• In general, we can say that a “quality” electric
motor should have a designed life in excess of
20 years.
• In reality, actual motor life in
an industrial environment is
probably closer to between
5 and 10 years.
Temperature effect on motor life
•
•
Insulation life
•
•
•
•
•
Heat is the #1 cause of reduced insulation
life
Winding insulation is rated according to it’s
thermal capability
For every 100 C above rated temperature
cuts life by 50%
For every 100 C below rated temperature,
motor life increases by a multiple of 2
Common overheating sources beyond
basic design
• Overload
• Inadequate ventilation
• Dirt buildup
• Phase unbalance
• High/Low voltage
Bearing life
•
•
Bearing temperatures are typically 50-75%
of winding temperature
Temperature impact (+ 100 C = 50% life)
Types of failures
Other
(12%)
Motors fail for a variety of reasons.
Rotor
(10%)
 EPRI study of 6000
utility motors
But, with proper maintenance, you can reduce or eliminate most causes.
Bearings
(41%)
Stator
(37%)
Breakdown of motor component failures
Operating Abuse
• Induction motors will operate under the most
adverse conditions. These adverse conditions are
usually preventable, unfortunately a great majority
of the time Failures are based on operating abuse
by humans who do not fully understand the impact
they have on the motor.
Bearing failures
(Equate to more than 40% - 50% of motor failures)
•
•
Most bearing failures can be prevented as they mostly stem
from too much or too little lubrication. Too much lubrication will
force grease/oil into the motor and then the winding. This leads to
pressure (increased friction) on the bearings that results in heat
(Can also lead to winding contamination failure).
Additional causes for bearing failures include: Coupling
misalignment, Contamination from external environment (such
as water, dirt, etc.), mixing incompatible greases and oils, motor
mounting issues that cause a “soft – foot” condition leading to
vibration, shaft circulating currents; caused by magnetic
dissymmetry (inherent in larger motors approx. 800HP and up),
VFD drives powering a motor with a chopped waveform and
magnetism induced into the shaft or frame of a motor can also be
a source
Over lubricated
Under lubricated
Human error in too much and too little
grease
Broken Shaft
Heat damage from failed bearing
Excessive belt tension causing shaft and roller bearing failure
Winding Failures
(Contribute to approximately 30% to 37% of motor failures)
•
•
Mechanical overload is the leading cause of winding failures. Operating a
motor only 15% above rated load can reduce winding thermal life to one
fourth of normal. A common misunderstanding is that motors can be
continuously loaded into there service factor. The service factor is intended for
short term, intermittent use. The solution to mechanical overload is simple,
reduce the load to no more than the HP rating of the machine (Failures due
to excessive heating in the winding).
Starting and stopping a motor. The hardest condition on an electric motor
is starting. When the power button is pressed an electric motor starts from
standstill with the connected load and accelerates until it reaches full speed.
What is happening in the motor is very stressful because the inrush current
can be 5 to 10 times the operating current during the acceleration time. This
causes tremendous heat in the rotor and stator. This heat translates to
thermal expansion and movement. This movement over time will lead to
failure. If a motor is not allowed to cool between starts it will subject the
stator winding and rotor bars and rings to high thermal conditions and will
greatly shorten the life of a motor.
Playing with Electricity!
Thermal damage
Grounded winding
Winding overload showing overall heat damage and a
ground failure
Rotors account for up to 10% of
failures
Cracked Bar
Cracked shorting ring
Examples of excessive starting/stopping and the
resultant rotor damage
Bar to Ring crack
Bar lifting out of rotor slot
Don’t Overload a motor like this!
Contamination
Internal
External
Contamination internal and external both causing over heated windings
A motor that hasn’t been maintained…
When replacing or installing motors these are the
important parameters to focus on:
•
•
•
•
•
•
•
•
•
The original motor nameplate: The nameplate holds a lot of valuable
information often over looked.
Performance information (Including the Speed vs. Torque curve and the
maximum inertia the motor was designed for).
The original load “Speed vs. Torque” curve and inertia (WK² in units of LB-FT²)
The actual system starting voltage (Or voltage drop during start).
The inrush current capability of the control starting system. (I.e. Breaker or
contactor or other)
You must match the KVA code or be aware of the differences between the
original and new/used motor replacement..
The service factor needs to be understood…
The motor temperature rise needs to be understood….
The motor enclosure…the motor frame dimensions and details
FAILURE INVESTIGATION
PROVIDING SOLUTIONS
• THE GOAL IS TO PROVIDE SOLUTIONS TO YOUR MOTOR/SYSTEM
PROBLEMS.
• FOCUSING ON THE DETAILS HELPS TO SUPPORT A BETTER
UNDERSTANDING OF WHAT IS ACTUALLY WRONG WITH YOUR
SYSTEM AND/OR MOTOR.
• IT BEGINS WITH OBTAINING SPECIFIC INFORMATION ABOUT THE
MOTOR BEING REMOVED FROM SERVICE.
BACKGROUND INFORMATION
•
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•
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What is the Application?
How long has motor been in service?
What is the environment surrounding the motor?
What are the starting conditions for the motor?
What is the Reason for removing the motor?
What predictive measures and trends support
removing the motor?
The past repair history and trends?
DETAILED INSPECTIONS
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•
After obtaining the specific background information for your motor
we then begin the process of a detailed inspection.
For each motor being repaired, HECO has developed unique “Repair
Packets” that provide a step by step approach to the inspection for
each specific motor type.
Example:
AC Sleeve Bearing Motor Repair Packet
A.C. SLEEVE BEARING
MOTOR REPAIR PACKET
REVISION SUMMARY
Page
No.
Description
Prepared By:
Date:
Approved By:
Date:
Revision #
16
REPLACED THE CAUSE OF FAILURE WITH MOTOR
OBSERVATIONS/FINDINGS
DMN
1/21/14
TAH
1/21/14
12114
17
ADDED A PLACE TO RECORD HECO/CUSTOMER ASSET #
AND TO CONFIRM LEADS IN TERMINAL BLOCKS DO NOT
HAVE METAL TAGS.
DMN
1/21/14
TAH
1/21/14
12114
18, 19,
20
REMOVED THE CALIBRATED INSTRUMENT LOG AND THE
PARTS CLEANING REVIEW PAGE. THESE WERE REPLACED
WITH COMBINED DEPARTMENTAL FORMS FOR BOTH,
CALIBRATION AND FINAL Q.A.
DMN
1/21/14
TAH
21/21/14
12114
3
ADDED A PLACE FOR KLIXONS AND RATING.
DMN
4/21/14
AJ
4/21/14
42114
5
ADDED A PLACE TO DOCUMENT MEGS BEFORE PREHEAT
AND THE PART TEMPERATURE BEFORE D/B
DMN
4/21/14
AJ
4/21/14
42114
ACSLMRP REV 42114
OBSERVATIONS AND FINDINGS
With every inspection, HECO will document the
Observations and Findings for that particular motor.
This information focuses on what we found during the
inspection process and how this information relates to your
reason for motor removal.
We then categorize our findings into 4 areas:
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•
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Electrical
Mechanical
Contamination
Preventative Maintenance
MOTOR OBSERVATIONS / FINDINGS
JOB: _________
CUSTOMER: ____________________
DATE: _______________
EMPL# ___________
APPLICATION: _____________________________________________ TYPE OF STARTING:
___________________________________________
TIME IN SERVICE: _______________ REASON FOR REMOVAL OF UNIT: ________________________________________
SUMMARIZE ACTUAL FINDINGS:
RELATIVE PICTURE #’ S
RECOMMENDATIONS / COMMENTS:
COMMENTS OR ADDITIONAL INFORMATION REQUIRED:
CHECK THE PRIMARY CATEGORY TO FINDINGS, THEN IN NUMERICAL ORDER, NUMBER OTHER FINDINGS AS A RESULT OF PRIMARY
ELECTRICAL
MECHANICAL
CONTAMINATION
TURN TO TURN
PHASE TO PHASE
GROUNDED
BEARING
LUBRICATION
SHAFT
WATER
CHEMICALS
OIL
SINGLE PHASED
VIBRATION
DIRT
LEADS BLOWN
SHAFT CURRENTS
CARBON
PARTIAL DISCHARGE
SHAFT MAGNETISM
PLUGGED FILTERS
OVER HEATING
SEALS
PLUGGED VENTS
SURGE / SPIKE
SIZE / TOLERANCE ISSUE
CONTAMINATION
INSULATION DEGRADATION
OTHER:
OTHER:
PM
STANDARD P.M.
OTHER:
INFORMATION REVIEWED BY: ____________________________ DATE: _________________
2/20/14
MIF v2
MOTOR OBSERVATIONS / FINDINGS
JOB: _9636__
CUSTOMER: _DETROIT EDISON__
DATE: _12/20/14_
APPLICATION: _COAL MILL MOTOR___ TYPE OF STARTING:
____
EMPL# __422___
ACROSS LINE____ TAG# MMO00091
TIME IN SERVICE: _N/A_ REASON FOR REMOVAL OF UNIT: _TRIPPING BREAKER ON START-UP__
SUMMARIZE ACTUAL FINDINGS:
MOTOR WAS SENT IN DUE TO TRIPPING BREAKER. FOUND SLEEVE BEARING WIPED WHICH CAUSED ROTOR TO DRAG
STATOR WHICH GROUNDED WINDING.
RELATIVE PICTURE #’ S
TD: 22, 23, 36, 37, 38, 39, 40, 44, 60, 67, 68, 78, 96, 100, 101, 104
RECOMMENDATIONS / COMMENTS:
RECOMMEND CUSTOMER MONITOR BEARING TEMPERATURES TO ALLOW FOR A SHUTDOWN BEFORE CATASTROPHIC FAILURE.
COMMENTS OR ADDITIONAL INFORMATION REQUIRED:
THIS IS A REPETATIVE DESIGN CHANGE ON THE ROTOR. HECO IS INSTALLING A HECO ROTOR DESIGN, ADDITIONAL TO
ALL OTHER REPAIRS.
CHECK THE PRIMARY CATEGORY TO FINDINGS, THEN IN NUMERICAL ORDER, NUMBER OTHER FINDINGS AS A RESULT OF PRIMARY
X
MECHANICAL
ELECTRICAL
TURN TO TURN
3
2
CONTAMINATION
BEARING
WATER
PHASE TO PHASE
LUBRICATION
CHEMICALS
GROUNDED
SHAFT
OIL
SINGLE PHASED
VIBRATION
DIRT
LEADS BLOWN
SHAFT CURRENTS
CARBON
PARTIAL DISCHARGE
SHAFT MAGNETISM
PLUGGED FILTERS
OVER HEATING
SEALS
PLUGGED VENTS
SURGE / SPIKE
SIZE / TOLERANCE ISSUE
CONTAMINATION
INSULATION DEGRADATION
ROTOR RUBBED STATOR I.D.
OTHER:
OVERLOADED
OTHER:
1
OTHER: ROTOR RUBBED
STATOR IRON
INFORMATION REVIEWED BY: __AL JESKE______ DATE: __12/20/14____
PM
STANDARD P.M.
MOTOR OBSERVATIONS / FINDINGS
JOB: _7236_
CUSTOMER: _LTV____
DATE: __12/2/13_
APPLICATION: _PICKLE PLANT__ TYPE OF STARTING:
TIME IN SERVICE: _6 MONTHS
EMPL# _506__
___SOFT__________
REASON FOR REMOVAL OF UNIT: _BEARING NOISE___
SUMMARIZE ACTUAL FINDINGS:
DURING INCOMING TEST RUN, MOTOR HAD A NOISY BEARING. UPON DISMANTLE, FOUND WATER IN THE D.E.
HOUSING. THE D.E. BEARING FAILURE WAS DUE TO MOISTURE ENTERING THE HOUSING, CONTAMINATING THE
GREASE. THE HOUSING WAS OVERSIZE.
RELATIVE PICTURE #’ S
7, 8, 9, 13, 15, 16, 22
RECOMMENDATIONS / COMMENTS:
Add an impro seal to the drive end to help prevent water entering.
COMMENTS OR ADDITIONAL INFORMATION REQUIRED :
CHECK THE PRIMARY CATEGORY TO FINDINGS, THEN IN NUMERICAL ORDER, NUMBER OTHER FINDINGS AS A RESULT OF PRIMARY
ELECTRICAL
TURN TO TURN
X
CONTAMINATION
MECHANICAL
2
BEARING
1
WATER
PHASE TO PHASE
LUBRICATION
CHEMICALS
GROUNDED
SHAFT
OIL
SINGLE PHASED
VIBRATION
DIRT
LEADS BLOWN
SHAFT CURRENTS
CARBON
PARTIAL DISCHARGE
SHAFT MAGNETISM
PLUGGED FILTERS
OVER HEATING
SEALS
PLUGGED VENTS
SIZE / TOLERANCE ISSUE
CONTAMINATION
INSULATION DEGRADATION
ROTOR RUBBED STATOR I.D.
OTHER:
OVERLOADED
OTHER:
SURGE / SPIKE
3
PM
STANDARD P.M.
OTHER:
INFORMATION REVIEWED BY: __AL JESKE______ DATE: __2/11/14___
2/20/14
MIF v2
TRENDING OF INFORMATION
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We gather this information over time on a
spreadsheet and begin to develop valuable data
about the categories and areas that your motor
problems fall into. This information is eventually
provided back to you to help you in your
preventative maintenance and to support your
decisions for deciding what motors should be
removed and what areas you may need
additional support & training.
DETROIT EDISON
PRIMARY
#1
MECHANICAL
BEARING
PM - OUTAGE
PM
SIZE/TOLERANCE
U2 W. COOL WATER MOTOR
PM - OUTAGE
PM
NORTH MAIN VACUUM PUMP
PM - OUTAGE
PM
FRAME
MODEL
S/N
APPLICATION
3030S6
129
1-5116-11444-2-3
UNIT 2 #7 COAL MILL
TRIPPED BREAKER
365TZ
TDFC
7008
MTG TURNING GEAR
326TS
5KS326STE115
S85098343
364TS
SD2P75TS61Y
U3980906280
7295-9
N/A
280277411
P.A. FAN MOTOR
326TS
DVH326TSTF56536FVL
7109905-07/20-02
"A" TRAIN ANION PUMP
REASON SENT IN ????
SATURATED WITH OIL / INSTALLING SPARE
PM
#2
#3
ROTOR RUBBED
STATOR IRON
GROUNDED
LUBRICATION
BEARING
SIZE/TOLERANCE
WATER
BEARING
SIZE/TOLERANCE
MECHANICAL
SEALS
OIL
DIRT
ELECTRICAL
INSULATION
GROUNDED
LUBRICATION
Finding the Root Cause & Providing Repair Solutions
HECO is well known for solving problems with
Electric Motors. As we partner with our customers,
we begin to understand where repetitive problems
are occurring & through this process of asking
better questions and understanding the customer,
we can provide improved motor designs to support
the elimination of repetitive failures.
Engineering Design
Evaluations & Assessments
In our evolution of identifying motor problems and providing a
solution, we will often go another step and provide our customers
with a Detailed Engineering Assessment.
The beginning of this process is gathering more information
specific to your application.
In all cases we will ask the customer for original design information
about the load (such as “Speed vs. Torque” Curve and Inertia Wk²
of the load and original motor performance information)
DESIGN CHANGE INFORMATION SHEET
DATE REQUEST TAKEN:_________________
HECO JOB #:___________________
CUSTOMER NAME:_______________________________ CUSTOMER CONTACT:__________________________
PHONE # OR EMAIL:__________________________________ HECO SALESMAN:__________________________
ORIGINAL DESIGN DATA
EQUIPMENT TYPE:
INDUCTION MOTOR ____
TRANSFORMER ____
MFG: ________________ HP / KW: ____________
RPM: ____________
TYPE: ____________
FRAME: ______________
SYNCHRONOUS ____
WOUND ROTOR ____
OTHER:__________________________
VOLTAGE (AC OR DC): _____________ AMPS (AC OR DC):____________
DESIGN: ______________________
STYLE: ____________
DC ____
S.F.:_______________
CODE: ____________
MODEL: _______________________
SERIAL: ________________________ (FLD. DATA) VOLTS DC: ____________ RESISTENCE: _____________
TEMP.:________________
TEMP. RISE:_________________
AMBIENT
REQUESTED REDESIGN CHANGE TO
______________ HP / KW
_________________ VOLTAGE
_____________RPM
__________________OTHER
___________________________________________________________________________________MECHANICAL
NOTES: _______________________________________________________________________________________
______________________________________________________________________________________________
QUESTIONS TO ASK CUSTOMER
1.
2.
3.
4.
5.
6.
7.
8.
9.
PURPOSE OF DESIGN CHANGE? _______________________________________________________________
APPLICATION (ie. LOAD) ? ______________________________________________________________________
LOAD SPEED V/S TORQUE CURVES (NEED THIS FOR COMPLETE DESIGN CHANGES, ATTACH TO FORM)
TYPE OF STARTER (IE. ACROSS THE LINE, ETC.) ? ________________________________________________________
DOES UNIT START UNDER LOAD: ____ OR UNLOADED ____
INERTIA OF LOAD; WK² = _______
HOW LONG HAS THE UNIT LASTED OR BEEN IN THE ORIGINAL DESIGN? ___________________
# OF STARTS PER HOUR OR DAY? _____________
DUTY CYCLE:________ HRS./WEEK
ACTUAL MEASURED VOLTAGE: ________________ CURRENT: _______________ SPEED: _______________
(HECO CAN MEASURE IF NEEDED)
SKIN TEMPERATURE: ______________________
APPROVED REDESIGN CHANGE
________________HP / KW
_______________VOLTAGE
_______________RPM
_____________ AMPS
_______________ OTHER _____________________________________________________________MECHANICAL
S.F.: ___________
INSULATION CLASS: _______________ NOTES:_______________________________________
______________________________________________________________________________________________
APPROVED BY: ________________ DATE:____________ CUSTOMER APPROVAL: __________________ DATE:_____________
DCIS Rev.2014
Real example for a Utility
The following is an example of what we have talked about in
this presentation. Back in 2006 HECO was offered the
opportunity to review motor failures common to a Utility
Company Coal Mill Motors.
(I.e. Siemens Allis, 800HP, 890 RPM, 4000 Volt, 112 Amp,
horizontal, sleeve bearing motors).
At that time the customer provided back ground
information to HECO and expressed the need for a solution
that would be long lasting and truly solve the repetitive
motor problems they were experiencing. There were a total
of 32 Coal mill motors (30 in service with 2 spares).
Issues found with these motors
These motors are a special design which has a double rotor bar
cage assembly. This is needed due to the hard conditions of a
coal mill application and required torques needed.
Double cage rotor design
After dismantling these motors the problems centered around the rotor design.
The original problem was cracking of the inner cage shorting rings.
Additional problems
Porosity & Cracks In the outer shorting ring fan assembly
More problems
Application information was obtained from the Utility on the existing motors.
Note: In every Engineering Design Assessment the following information is important to obtain, to
successfully identify/compare and perform a complete design verification review.
Obtaining the original performance and load
information is vital in providing alternative solutions to
your problems.
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It provides details about the original motor design.
It provides load information needed for engineering
calculations and torque requirements.
It allows a cross check of the new design to the
original and how they compare.
It confirms whether a design will work or not.
Samples of the bar/shorting ring materials were sent to a laboratory for identification. The analysis
came back as follows:
BARS
The upper bar (Outer cage) was .500” diameter and had a conductivity of 23.6% (Copper alloy). This
was identified as C464 Naval Brass.
The lower bar (inner cage) was .375” wide x 1.00” tall and had a conductivity of 98.6%.This was
identified as 99.9865% copper, C11000 (Pure copper).
SHORTING RINGS
The upper shorting ring (outer cage) was a phosphorous copper alloy with a conductivity of 63.5%.
This copper alloy was not directly identified with today’s alloys but its closest match was C21000. This
shorting ring also had the cooling fan “casted” as part of the shorting ring. This causes the shorting
ring configuration to be special thus adding cost and longer material deliveries. (In other words, this
design isn’t practical for repairing in the future, because the shorting rings would have to have a
special copper alloy casting to match the original configuration. This causes the repairs to take longer
and is more costly.)
The lower shorting (inner cage) was a phosphorous copper alloy with a conductivity of 60.1%. This copper alloy was also
not directly identified with today’s alloys but being closest to C21000. This ring was slotted as shown below. NOTE: This
shorting ring design is mechanically weaker due to the machined slots in the ring.
Due to the original design configuration of both inner and outer shorting rings, HECO is offering an alternative to both ring
designs. The inner ring has inherent weakness due to the slotted design. HECO has designed an alternative ring that is
mechanically stronger and 1/8” thicker (Original ring 3/8” thick and new trough style ring ½” thick). This ring design is called
a “Trough” ring where the bars are inserted into a machined trough in the face of the ring. This trough is silver soldered to
short & connect all the bars electrically and mechanically. (An example of a similar design is shown below. This design
is larger but the concept is the same).
Machining the “Trough” of a larger ring.
The photos above show the vertical set up and (15% Silver Brazing) welding of the bars in the trough
design. When complete the bars/shorting ring joint is mechanically much stronger. The ring is then
machined to a final size and the rotor is cleaned of all flux etc.
The outer shorting ring would be a shorting ring as original, except without the fan blades as part of the ring.
We would offer a fabricated steel fan (Same shape/blade area and number of blades) that would either mount
to the shaft or the shaft spider assembly. This design would provide cooling fans that are removable and allow
for better inspection of the shorting rings and an improved design for future repairs (a more practical approach
for future repairing and rotor bar/shorting ring replacement.
After performing an engineering design analysis, we have identified that the original ring material (60%
conductivity) is not necessary for the performance or motor torque requirements. This same
performance can be achieved by replacing with a 100% copper shorting rings (100% conductivity).
This provides a more readily available shorting ring material option for this repair and future repairs (The current
material is a material that is more costly and is not readily available (approximately 6 – 8 weeks). As with most
induction rotors of this speed (# of poles) the shorting rings play a very small role in the production of torque. The
resistivity (or conductivity) of the bars are the most important component for production of torque and
performance.
HECO’s concept for the new design would follow the sketch below:
.
Note: The “Trough” style inner ring at ½” thick (original 3/8” thick). Both rings would be made
from 100% copper (100% conductivity).
This design will allow for an improved mechanical design (Inner ring) and a more
practical material selection (for shorting rings). This will allow future rotor repairs to be
simplified and not dependent on a material that is not available or a long lead time.
Motor torque is effected by the bar resistance (which consists of: bar length, bar area,
# of bars and the bar conductivity) and ring resistance (which consists of: ring thickness,
mean diameter, ring area, # of (poles)², and ring conductivity). The change in ring
resistance is minimal and the bar resistance is still the dominant factor producing
the majority of motor torque.
What does this mean in terms of performance? Following is a chart that compares
the performance difference of the original rings (60% conductivity) to the new copper
rings (100% conductivity).
Original
LRT
224 %
BDT
275 %
LRA
728
Stall Time
3.2
Acc. Time
3.0
Rotor Bar (°C)
111
Rotor Ring (°C)
6
New
222 %
272 %
726
3.1
3.0
110
5
As you can see, the effect of changing the rings to copper is very small in relation to
performance.
New Rotor details and pictures
Storage Maintenance
Storing for Reliability
A motor in storage on-site is there for one primary purpose:
It needs to be available for quick installation when an operating
production motor goes down.
Maintenance of electric motors in storage is a critical,
but often over-looked function.
Performing a few, relatively simple maintenance
items during storage will help ensure a motor is
ready to be installed and operates reliably.
Storage
Problems
Problems that may occur during extended motor storage basically fall
into two categories
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Coil insulation deterioration
Condensation collects on the stator coils, eventually
lowering insulation resistance to ground
•
Bearing damage
Condensation contaminates bearing grease
Grease hardens and loses it’s ability to lubricate
Stationary brinelling of the bearing race
Storage Recommendations
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•
If at all possible,
electric motors
should be stored in
a clean, dry, low
humidity
environment.
• This will help prevent
condensation buildup on windings and
bearings
If motors are
equipped with
space heaters, they
should be
energized.
Storage
Recommendations
Machines with oil lubricated bearings require being
filled with oil when motor enters storage (Motors ship
dry from the factory)
Rotate the motor shafts quarterly.
• Distributes lubricant to machined surfaces
• Prevents false brinelling damage
Grease motor bearings require re-lubrication during
extended
storage.
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Every 6 months to a year during extended
storage
Storage Recommendations continued
• During extended storage, all motors should have their
insulation resistance checked and recorded at periodic
intervals.
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A 50% drop in the resistance-to-ground requires corrective
action
Correct insulation resistance to ground (Megger) for
temperature changes following IEEE 43-2000 and trend.
The Motor System
“Systems” Approach
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Utilizing A foundation based on experience, we suggest a
systems approach to motors and equipment reliability.
This foundation is built on solving electric motor problems and
providing long term solutions. In addition we direct our focus
from only the motor, to include the reliability of the complete
system.
Many of the problems & solutions are found to be in other parts
of the system, I.e. foundation, alignment, driven equipment,
etc.
Asking detailed questions, beyond the motor; including the
application, supports creating a better understanding of the
whole system which provides for long term solutions.
12 Step
HECO MAPPS
(Motor And Powertrain Performance System)
HECO MAPPS
HECO MAPPS is designed to optimize the
performance of your electric motor-driven
powertrains.
MAPPS will lead you to
reducing downtime costs,
keeping problems from recurring
and keeping your operation running.
Step 1:
Equipment Survey & Identification
• Survey all assigned equipment
• Record all nameplate data & other critical data
• Tag each asset individually with unique ID number
• Identify asset plant location and application information
• Categorize assets and applications
• Enter survey data into reliable database (Such as HECO’s
TracRat database system)
Survey Sheet Example (Motor
Only)
Step 2:
Review Practices & Implement Specifications
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Identify existing repair and new purchase specification
practices for each asset type
Review existing practices and makes recommendations to
improve quality and consistency
Creation of corporate specifications with specific exception
reports per plant area and application
Implement specifications by asset types and sizes
Step 3: Review Procurement Processes
• Assess existing new & repair procurement
process
• Establish new v/s repair determination levels
• Review and implement authorization process
• Implement procurement process that is
based around reliability and established
specifications
Step 4: Perform Partner Assessment
•
Survey all partners across all asset types/sizes
•
Tour all partners across all asset types/sizes
•
Establish partner certification process
•
Select partners based on assessment results
•
Create partner volume discounts
Step 5: Spare Asset Management
• Centralized v/s Decentralized storage
• Identify “current” storage practices & locations
•
Including preventative maintenance practices
• Identify “proper” storage practices and
locations
• Identify min and max levels
• Identify “cross-over” assets
• Reaction time of storage centers
HECO’s 170,000ft2 warehouse
in Hammond, IN
Step 6: Asset Repair Management
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Establish pricing format for high volume assets
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Develop approval process for repairs
•
Establish cause of failure evaluation process
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With a focus on root cause analysis
•
Audit & continually improve partners
•
Track all repair history in one common location
Step 7: Predictive and Preventative Maintenance
• Assess current practices
• Establish practices, as needed
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•
•
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Vibration practices
Thermography practices
Electrical Evaluation practices
Lubrication practices
Alignment practices
Oil Particle Analysis
Step 8: Dedicated Technical Specialists
• On-Site validation of all critical assets
• Oversee removal and installations
• Assist partners with root cause failure analysis
• Make recommendations on proper operation
• Work with all maintenance groups
• Monitoring of all critical asset application conditions
• Continuous documentation & record keeping
Step 9: Engineering and Applications
•
•
•
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Identify proper repair methods with an
engineering and reliability focus
Take a “systems” approach to failures
Use historical data to your advantage to put the
proper piece of equipment in the proper
application
Focus on system improvements
Step 10: Training
• Assessment of current knowledge levels
• Establish training programs based on current skill levels
• Establish and implement training around the needs
identified by the assessment reports
Step 11: Software Database
•
Central communication database (Like HECO’ s TracRat) for all
repairable assets
• Never loose historical information – it’s like a “medical record” for your
repairable assets
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•
•
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Track all repair history and new purchases in one location across all
asset types
Warranty tracking
Repair statuses
Cause of failure reporting
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•
•
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By location, asset type, manufacturer, failure types, etc.
Mean Time Between Service (MTBS) reporting
Ease of access to information through internet and web browser
Adaptable to track additional information
Step 12: Establish KPI’s
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•
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•
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MTBS (Meantime Between Service)
Down time dollars by asset type
Asset Repair Cycle Report
Savings report
Inventory reports
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•
(Key Performance Indicators)
Min/Max Levels
In-Service to Spare analysis
Inventory amount reports
On-Time delivery reporting
Dollar spend v/s budget by repairable asset type
Communication
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Single control point – Between customer and partner
Focus on long term reliability and cost
savings/avoidances
Create reliability team focus on each asset type
Schedule regular improvement meetings with each
asset reliability team
Create an aligned focus on corporate goals
NIPSCO 20 YEAR CASE STUDY
NIPSCO Early years
• Didn’t know how many motors they had in-service or as spares
• Didn’t have any detailed specifications that they followed
• Repair specifications was generic
• No specific Capital or replacement spec
• RFQ process was driven by low prices not by a apple to apple
comparison
• Many vendors no Partners
• Pour communications
• No database system for tracking
• No consistency with budgeting
• Firefighting not having time to get to the root of the failures
• Repeating Failures no accountability
• No detailed history on failures and past repairs
• Not looking at things as a complete powertrain system
NIPSCO 20 YEAR CASE STUDY
NIPSCO after a HECO MAPPS
(Motor And Powertrain Performance System)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Surveyed over 12,000 motors
Detailed Specifications
One focused Partner
On Site Technical Specialist
Fixed Pricing
Failure assessment and correction
Trust in a Reliable systems
Better Budgeting and Planning
Lower cost of doing business
Clear communication
TracRat web based database
Training
Focused Team from HECO and Customer
Millions in documented savings
Thank you
Questions?