Transcript Document

Magnaflux Quasar PCRT
Topics
• Functional Quality
• Magnaflux Quasar PCRT
• Detection Sensitivity
• System & Applications
Functional Quality
• Definition of Quality
– Visual Quality – rejects parts with visual indications that exceed
specifications (subjective)
– Functional Quality – rejects parts with structural degradation that will
cause premature field failure (objective)
• Functional Quality Requires NDT that:
– Measures structural properties
– Provides results that are traceable to failure levels
– Provides quantitative and objective reject criteria
• Resonance Inspection is the only NDT method that meets
these requirements
Resonance Theory Applied to NDT
• Resonant Frequencies are determined by the dimensions
and material properties of the whole part
fr  k
m
fr = resonant frequency
k = stiffness (e.g., Young’s Modulus)
m = mass (dimensions, density)
• Structural Defect = strength reduction caused by degraded
material properties or dimensional variation
• …therefore, a defect that reduces stiffness will shift the
resonant frequency
Experimental Verification
450
2
Break Force - lbs.
R = 0.9974
400
350
300
250
200
31.500
32.000
32.500
33.000
33.500
Resonant Frequency - kHz
Break Force vs. Resonant Frequency for PM Exhaust Flange
Process Variations Can Mask Defects
Good Rod 1
Small Defect 1
Large Defect 1
Good Rod 2
Small Defect 2
Large Defect 2
Good Rod 3
Small Defect 3
Large Defect 3
Statistical Analysis of Masking
Relative Number
Acceptance Window ~
Rejects 35% of Bad Parts
1.00
Average Range Sigma
Good 21.24
1%
0.2%
Bad 21.11
6%
1.4%
0.80
0.60
Good
Bad
0.40
0.20
0.00
21
21.1 21.1 21.2 21.2 21.3 21.3 21.4 21.4 21.5 21.5
Resonant Frequency - kHz
Distribution of Resonant Frequencies for 200 Master Cylinder Bodies
Relative Frequency Compensation
Good Parts
Peak
Separation
> 2.8 kHz
Bad Parts
Peak
Separation
< 2.0 kHz
Silicon Nitride Valves
Temperature Compensation
• Critical for accurate
measurements
– Quasar total error 0.03%
– Resonant frequency varies
with temperature
• Ferrous – 0.015% per °C
• Aluminum – 0.025% per °C
• Compensation measures
part temperature (+/0.5°C) and computes
equivalent frequency at
baseline temperature
23°C
68.400 kHz
31°C
68.318 kHz
23°C
68.397 kHz
Compensation Accuracy = 99.995%
Process Compensation Unmasks Defects
Relative Number
1.00
Acceptance Window
Range = 0.3%
0.80
0.60
Good
Bad
0.40
0.20
0.00
00 1 67 1 33 1 00
2
-
7
-6
4
-3
0
33
66
0
3
10 13
M
e
or
Predictor Error - Hz
Distribution of Predictor Error for 200 Aluminum Master Cylinders
Process Compensated Resonance Testing
• Resonance tests the whole part for all structural defects,
material differences, and dimensional changes
• Process Compensation separates changes due to defects
from those caused by normal process variations
• ASTM E2001-08 (RI) and ASTM E2534-10 (PCRT)
• Quasar PCRT takes the next step by applying statistical
analysis and pattern recognition to accept or reject parts
• NDT acceptance is based on objective functional quality,
not visual quality subject to operator error
MTS Pattern Recognition
MTS = Mahalanobis Taguchi System
Measured Frequency - kHz
21.40
21.35
21.30
21.25
Good
21.20
Bad
MTS Acceptance Window
21.15
21.10
21.05
21.00
21.15
21.20
21.25
21.30
21.35
21.40
21.45
Predicted Frequency - kHz
Measured & Predicted Resonant Frequencies for 200 Aluminum Master Cylinder Bodies
VIPR – Pattern Recognition Program
Bad Parts
Good Parts
Reject
MTS Cutoff
Accept
Accept
Reject
Bias Cutoff
VIPR computes the MTS (good part characteristics) and
Bias (bad part characteristics) to determine Quasar Score
Quasar Score Predicts Performance
450
B
r
e
a
k
F
o
r
c
e
P
o
u
n
d
s
F = -6.8 Q + 424.5
Where:
F is Break Force
Q is Quasar Score
400
350
Correlation = 99.8%
300
250
200
0
5
10
15
20
25
Quasar Score
30
35
40
Detection Sensitivity
• Common question:
– What size is the smallest defect that quasar can detect?
• Correct question:
– How much performance degradation can quasar detect?
• Answer – detection threshold depends on several variables:
– Definition of defect – statistically significant difference
• Defects must be structural, not cosmetic
• Failure distribution must be statistically defined
– Measurement R&R (precision, temperature, tooling)
– Available test time vs. Weight & complexity of part
Consortium Test of NDT Methods
30
# Misclassifications
25
20
15
88%
Effective
55%
Effective
56%
Effective
59%
Effective
100%
Effective
Visual
Prod X-ray
Film X-ray
ASNT FPI
Quasar
10
5
0
Good Part Errors
Bad Part Errors
Fatigue Test of 64 Aluminum Knuckles
Quasar 4200 System
Work Station
Test Station
Flat Panel
Display
Nest
Keyboard &
Mouse
Test Heads
Computer &
Transciever
Isolation Base
Quasar 4000 System Block Diagram
Receive
Transducers (2)
Proximity
Drive
Switch Transducer
User Interface
Thermocouple
Part
Control
Computer
Transceiver
Step Motor Lift
Accept/Reject
TEST HEAD ID
DeviceNet
PLC
Automation
Interface
System
UPM
Workstation
PLC
• Senses Part
• Raise / Lower
• Test Results
Test Station
Test Head Example
Tooling
Thermocouple
(Under part)
Transducers
(Under part)
Test Part (Dampening
Fork)
Resonant Vibration Modes
Test Part (Connecting
Rod)
Bending
Mode
Transverse
Bending Mode
Torsional Mode
Click for animation
Application Example #1
Rocker Arm
Before Quasar PCRI
Visual
Inspect
Cast
“Gas Hole”
Inspection
X-Ray
Sample
Autogage
Final
Visual
Machine/
Heat Treat
MPI 2
MPI 1
Second Level
Inspection
Visual
Cracks
Pack
/
Ship
NDT Opns.
8
NDT Cost
20% of Price
Scrap
7%
Returns
~100/yr
After Quasar PCRI
Cast
Rough
Inspect
Machine/
Heat Treat
Autogage
Quasar
Final
Visual
Pack
/
Ship
NDT Opns.
3
NDT Cost
4% of Price
Scrap
1%
Returns
0
Application Example #2
2 year Production Log
Cast Aluminum Master Cylinders
2 suppliers – 12 million parts
5.0
Leakers per Month
Transition
4.0
Pre Quasar
3.0
2.0
Full Quasar Testing
1.0
ay
-0
2
Ju
l-0
2
Se
p02
No
v02
Ja
n03
M
ar
-0
3
M
ay
-0
3
Ju
l-0
3
Se
p03
No
v03
Ja
n04
M
ar
-0
4
M
ay
-0
4
Ju
l-0
4
Se
p04
M
M
ar
-0
2
0.0
Leakers occur when aluminum oxides provide a channel from bore to surface
Quasar Production Systems
Examples of Quasar PCRI Applications
ABS Pump Bodies
Engine Mounts
ABS Rings
Flywheels
Bearing Caps
Gears
Brake Anchors
Knuckles
Bearing Hubs &
Races
King Pins
Brake Calipers
Links
Master Cylinders
Oxygen Sensors
Cam Caps
Pump Housings &
Rotors
Cam Shafts
Rocker Arms
Clutch & Pressure
Plates
Steering Racks
Connecting Rods
Sprockets
Control Arms
Synchronizers
Dampener Forks
Timing Rings &
Gears
Differential
Carriers
Transmissions
Shafts
Cylinder Heads
Wheels
Engine Blocks
Yokes
Examples of Structural Defects
Common Defects – All Processes
Cracks, Inclusions, Chemistry, Missing Features, Non-fill, Dimensions
Process-Specific Defects
Al Cast
Fe Cast
PM
Forge
Oxides
Oxides
Oxides
Bar Ends
Cold Shuts
Cold Laps
Chipped Teeth
Double Strikes
Shrink
Porosity
Shrink
Porosity
Porosity
Laps (folds)
Blow Holes
Nodularity
Sintering
Water quench
Elongation
Heat Treat
Coining
Wrong material
Carbides
De-carb
Other Processes – Welding, Ceramics, Composites
Quasar PCRI – Production NDT Benefits
• Lower Risk
– Lower probability of shipping defective parts
– Proper use reduces the risk of “quality spills” into the field
– Boost company marketing image
•
Lower Cost
– Reduced NDT Cost
– Reduced false-rejects and scrap of good parts
– Reduced returns and warranty costs associated with “quality spills”
Magnaflux Quasar
Systems
The Next Step in NDT
www.magnaflux.com
Magnaflux Quasar Systems
5550 Midway Park Place NE
Albuquerque, NM 87109
Phone: (877) 847-3067
Fax: (505) 212-5422
Magnaflux Global HQ
3624 West Lake Avenue
Glenview, IL 60025
Phone: (847) 657-5300
Fax: (847) 657-5388