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UNCONFIRMED MINUTES OF
SAE Fatigue Design and Evaluation Committee Component Test Division Fall 2001 Meeting, Tuesday 16 October –
Division Progress Meeting
The
minutes of the division’s progress meeting and planning session held 3-4 April
2001 were approved. As was noted for
all divisions, anyone who did not receive the minutes via E-mail (Al Conle’s
distribution list) or did not look at the minutes at the “fatigue.org” site
did not see the minutes, as they were not posted at SAE’s web site. ATV
Status – Ric Mousseau
Ric
noted that a few of the presentations in Wednesday’s technical session would
provide information about the ATV project during the last six months. Presentation:
“Vibration Theory and Practice of Failure Mode Verification Testing” –
Alex Porter FMVT is based on testing for any condition that can
break the design. All load sources
are input as random profiles, not profiles based on road load data or nominal
operating conditions. Nominal
loading tends to be a narrow representation of the potential failure sources,
leading to tests that generate only the expected (biased) failure types.
FMVT uses six-axis random vibration.
Multiple failure modes can be found when inputting all identified stress
sources such as vibration, temperature, and humidity.
The presentation showed an example of testing on an instrument
panel/cockpit system, using 6 axes of loading plus temperature, humidity,
simulated sunlight, and actuation of duty cycle features like pedals and
switches. 14 hours of testing on
this system found 62 potential failure modes, of which 8 have known warranty
history, and 41 probably would not have been found through conventional methods.
FMVT needs a large spectrum; this need required an evaluation of
different types of equipment for the loading.
Capabilities in frequency and displacement had to be considered.
FMVT uses chaos theory-based recursive control to achieve response
spectra in frequencies far above those of the relative low “operating”
control frequencies. The chaos
equations of the control achieve very drastic changes in behavior from
relatively small changes in coefficients, and the equations have symmetry of
scale. The behavior can eventually
bifurcate into non-repeating randomness. The
presentation demonstrated this rapidly changing behavior via application of the
equations to the creation of music. The
FMVT system controls the base frequency, the rate of iteration, and the energy
level. Presentation: “Accelerating a Durability Test
with Fatigue Editing” – Kurt Munson The
goals of the test-building project were to create a test schedule capable that
reproduces a heavy truck’s service life in a short time, and to run a
multi-axis test based on that schedule. Data
collection covered 15 events and over 12 hours of customer use, utilizing 16
strain channels for durability analysis and 32 acceleration channels for test
control and modeling. The actual
time for the vehicle’s service life is about 12,000 hours, but the target time
for the lab test was <400 hours. The
data channels included vehicle accelerations for test control and strain gages
for correlation. The test was to use
several hydraulic actuators attached to the vehicle frame, and was to be
time-based to reproduce variable amplitudes and vibration modes.
The long, unedited strain histories were from 15 field events.
These were the histories subjected to fatigue-based editing.
The fatigue calculation parameters for editing included strain-life data
provided by the steel supplier, as well as a Kf determined by back-calculation
from component test data. Damage
histories were determined at each critical location.
The time histories were divided into frames of a size equal to the
inverse of the lowest frequency of interest.
The determination of frames to retain was via a Boolean OR function, i.e.
if notable damage occurred at one or more locations during a given time slice or
frame, the frame was retained for all channels.
The retention of all channels is necessary to maintain phasing.
In order to meet the test length target of 400 hours or less, a damage
retention target of 40% was used, and the retained test content was repeated 2.5
times in order to return to 100% of field damage.
An exceedence plot for one of the critical strain channels showed the
cycles distribution of the edited data converging with that of the unedited data
for strain ranges of ~700 me and higher.
The frequency content before and after editing was compared to verify
that proper structural excitation was maintained.
The resulting lab test was successful at reproducing several field
incidents. Wednesday
17 October – Division Planning Session
Ideas
and proposed studies were discussed for assessing variability in the loads of
the ATV dynamic model as a function of the following variables: payload,
springs, shocks, steering, speed, and the test track.
What creates the worst case? Attendees
of the session re-stated the availability of Caterpillar Component
Technology’s facility and equipment for bolt fatigue testing.
This availability had been noted previously in a Tuesday presentation
about bolt fatigue results. Please
contact Dan Lingenfelser or Jeff Nash if interested in more information. Time
limitations in the session prevented discussion of additional possible project
initiatives in the division. However,
ideas for such initiatives, which were listed on overhead sheets during the
session, are listed here: Variability
and uncertainty studies Accelerated
testing (new methods, how much acceleration is too much) Thermal
fatigue testing (and acceleration thereof) Projects
of potential cooperation with the Structural Analysis division. THE
DIVISION IS STILL SEEKING A VOLUNTEER FOR VICE-CHAIRPERSON! Respectfully
submitted, Paul
Lubinski Chairperson,
Component Testing Division 812
341 2362 Paul.lubinski(at)arvinmeritor.com UNCONFIRMED MINUTES OF SAE Fatigue Design and Evaluation Committee Structural Analysis Division Fall 2001 Meeting, Tuesday 16 October –
Division Progress Meeting
Mary
announced the new Structural Analysis Division vice-chairman of is Jin Qian. Greg
Glinka presented "Stress Concentration and Stress Distribution In Weldments,"
based on discussions with John Deere and Ralph Stephens. The approach to
structural analysis of complex cross sections to find local point stresses at
weld toe and apply standards with nominal stress is OK for test specimens, but
difficult to apply to real components. Therefore, he uses hotspot stresses or
average stresses. In offshore applications for tubular structures definition of
nominal stress is not unique. Finding
nominal stresses is not easy; and some other method is needed. He can use
detailed numerical analysis and get nominal stress from sections of interest
equal to hotspot stresses. He uses a method proposed by a Japanese analyst,
where mean stresses are calculated away from the weld toe, with two
stress concentration factors and linear extrapolation to the section of interest
all along the surface. He could also linearize the stress distribution through
the thickness. Greg's method uses
membrane stress and bending stress obtained from a shell element analysis of the
structure, as a direct output of hot spot stress.
He can then find stress concentration factors from membrane and bending
stresses. For example, fatigue
problems in a crane arm were caused
by local stresses not by a nominal bending stresses.
A shell finite element model of the entire box gave stresses in each
cross section. He calculated peaks
stresses for stress concentration factors from pure bending and stress
concentration factors for tension. Peak stresses
with were obtained with Neuber analysis, and then applied to damage
calculations. Another example was a
T-joint loaded in bending and tension. The
stress concentration factor for fillet depends on weld height and toe radius.
Greg applied his method to a T-joint modeled by Jin Qian with finite
element shell elements and found results compared closely to FEA results. The
key point is to split the stress into membrane and bending stresses from a shell
finite element analysis and apply to crack growth. Finite element stresses are
for uncracked sections. Greg also integrated weight functions and compared to
results from the Jim
McConville, from Mechanical Dynamics Inc., presented " A Survey of FEA
Based Stress Recovery Methods in Planning
Session Results. The activity plan,
generated during the meeting, is included below. SAE
FD&E -- Structural Analysis
Division Planning Session -- Fall
2001
Respectfully
submitted, Mary
Wickham Chairperson,
Structural Analysis Division UNCONFIRMED MINUTES OF SAE Fatigue Design and Evaluation Committee Road Load Data Division
Fall 2001 Meeting, Tuesday
16 October – Division Progress Meeting 1.
Christoph Leser moderated the meeting. 2.
Minutes from the previous meeting were not
available and therefore not approved. 3.
Robert Geisler of GM gave a presentation entitled:
"Using Analytical Loads Prediction to Using Analytical Loads Prediction to
Assist in Generating Laboratory Assist in Generating Laboratory Dynamic Loads
for Durability Testing Dynamic Loads for Durability Testing" 4.
Darragh Murphy of MTS Systems Corporation gave a
presentation entitled: "Automated Road Load Data Analysis for Verification
of Data Integrity" 5.
Christoph Leser of MTS Systems Corporation gave an
update on "ATV Shock Absorber Load Modeling"
Wednesday,
October 17 - Divisional Planning Meeting Christoph Leser chaired the
meeting As per the last meeting the
RLDA group will support the ATV group when requested. New
activities
- no proposals for new activities were made. The RLDA group will evaluate
"automated data analysis tools". To this end MTS and nCode will be
contacted to use their automated tools on existing SAE ground vehicle load
records. To verify that the original histories are valid Tom Cordes of John
Deere and Brian Dabell (formerly GKN) of nCode and Mark Early on the recently
acquired ATV records could be contacted. Efstatios Nikoladis suggested
reviving statistical road load analysis. There is an SAE committee on
probabilistic Design that he will contact to give us input on how statistical
variations in loads need to be considered for to account for probabilistic
aspects in design. The meeting was adjourned. Respectfully
submitted, Christoph
Leser Chairperson,
Road Load Data Division UNCONFIRMED MINUTES
OF SAE Fatigue Design and Evaluation Committee Fatigue Life Prediction Division
Fall 2001 Meeting, Tuesday
16 October – Division Progress Meeting 1.
Minutes from the previous (Spring 2001) session were unavailable and could not
be approved. 2.
Russ Chernenkoff reported on "High Mean Stress Level Tests". The
material for this test was a normalized 1045 steel (Phase II material from
FD&E biaxial project). Testing
was on axial samples using stress-control with strain monitored at room
temperature. Three sets of tests
were conducted:
Set 1 at constant max. stress = 381Mpa,
Set 2 at constant min. stress = -381Mpa,
Set 3 at constant min. stress =
0.0 The
data is on the website: http://fde.uwaterloo.ca/Fde/Highs0/racccc.html 3.
Chin Chan Chu discussed " Life Prediction for Specimens Subjected to High
Mean Stress Levels." The purpose of the analysis of this test data was to
help correlate methods from Tim Topper, Sop
= ? Smax [1-(Smax/Sy )2] + Smin 4.
The results of items 2 and 3 above have been accepted for publication in Int. J.
Fatigue paper by C.-C. 5.
Jeff Nash discussed "Bolt Fatigue." -
Mean stress affects were best predicted by Morrow equations. -
High preloads can drastically reduce fatigue life. -
For grade 9 bolts, half of failures were at the head. The
threads were ground and rolled after heat treatment. The primary failure was the
first engaged thread. Question: Have
you calculated the local stresses? Answer: No, looking for volunteers. 6.
Al Conle discussed information on the website at Respectfully
submitted, Al
Conle Chairperson,
Life Prediction Division UNCONFIRMED MINUTES OF MEETINGS OF SAE Fatigue Design and Evaluation Committee Material Properties Division Fall 2001 Meeting, Tuesday
16 October – Division Progress Meeting Minutes
of the April 3/4 2001 approved as written. 1)
The 2nd annual database awards were presented, and this year the awards went to
I) Peter Kurath for Ti6Al4V
Beta-annealed
II) NASA for 1100 aluminum, 304, 310 and AM350 stainless steels, Ti6Al4V,
Ti_5Al_2.5Sn,
and
4340 steel.
III) K. Endo and J. Morrow
(U.
IV) Brian Leis (U.
V) Ron Landgraf (U. Illinois)
SAE1045, SAE4142, and Maraging steel (several different
data sets of each). 2)
A Revised version of SAE J2409 (standard file format for exchanging strain-life
data) and the
new proposed format for overload data was briefly presented. 3)
Russ Chernenkoff (Ford) gave a brief synopsis of the digitization of the upper
and lower
ATV control arms. The
"step" files are available at the fde website.
Check the
link ftp://ftp.fatigue.org/data/ATV/Control_Arm 4)
Russ Chernenkoff then gave a presentation entitled "Mechanical Properties
of Aluminum
Composites for Forged Powder Metal Connecting Rods." This work was
performed under
the auspices of the USAMP program.
Pucks forged out of an aluminum metal matrix composite (2XXX class Al
alloy combined with 20% SiC) were solutionized, heat treated to T6 condition and
then machined into fatigue specimens. The
fatigue specimens were separated into two groups: one polished, the other shot
peened.
The room temperature fatigue strength of the shot peened specimens
(180MPa) was better than that of the polished specimens (150MPa).
Fractography showed that the initiation sites were primarily either SiC
clusters (distribution) and regions of poor interparticle bonding in the Al
alloy. No effect of inclusion
content was found. 5)
Al Conle gave a talk for Kin Yeung (Ford) entitled "Shaft Straightneing
Fracture Estimation". They
modeled the development of the residual stress distribution from the thermal
processing of an induction hardened shaft using ABAQUS.
After developing a satisfactory result they simulated a shaft
straightening operation (wherein a shaft which has warped due to heat treatment
is straightened mechanically) in order to predict the point at which the shaft
would fracture. By
modeling the case, core and two layers of intermediate hardness, they found that
they could predict both the forces used in straightening the shaft and those
necessary to fracture it, given reliable values of true fracture strain.
Further, they were able to predict the redistribution of residual
stresses as a result of the straightening operation. 6)
Ralph Stephens (U. Iowa) gave a talk entitled "The Influence of High R
Ratio on Unnotched Fatigue Behavior of 1045 Steel with Three Different heat
Treatments." High
tensile mean stress tests for R ratios of 0.8 and 0.9 were conducted on smooth
uniaxial fatigue specimens made from SAE 1045 steel with hardness levels of Rc
10, 37 and 50. S-N
curves for all three hardness levels for both R=0.8 and 0.9 were very flat
except Rc=50 specimens with R=0.8. The experimental results showed that at high
R ratios, the fatigue strength based on Smax
was higher than that for low R ratios but were lower when based on Sa.
Acquired e-N applied curves showed that cyclic creep was present for all three
hardness levels. At Rc=10 and 37 had more cyclic creep/ratcheting resulted than
at Rc 50. Scanning Electron Microscopy (SEM) analyses showed that Rc 10 and 37
specimens fractured in a ductile manner with cup-cone shaped final fracture,
where ductile dimples were dominant with small amount of micro cleavage. Rc 50
specimens fractured in a brittle manner involving less cyclic creep. Tensile and
cyclic (fatigue) final fracture surfaces were very similar for Rc 10, 37 and
short life (Nf <3000) specimens of Rc 50. The failures of these specimens
were caused by cyclic creep/ratcheting rather than fatigue cracking.
Rc 50 specimens with Nf>3000 were the only specimen group that failed
due to thumbnail surface fatigue cracking. S-N
and e-N life prediction models were compared. S-N models predicted actual
specimen lives better than e-N models, although none of the models was
successful in calculating the fatigue lives for high R ratios. Divisional
Planning Session, Oct. 16 1)
The revised version J2409 (strain-life data file format) was discussed.
Many new tags were added (both optional and mandatory) for monotonic
properties, specimen design, and material form.
A methodology was adopted for denoting "runout" tests.
This new standard has now been submitted to SAE for balloting. 2)
The proposed new standard for data exchange of overload fatigue datasets also
was discussed.
This file format shares the same tag definitions as the revised J2409,
but the actual data format is quite different.
This standard was also submitted to SAE for balloting. 3)
A proposal was forwarded for drawing up a standard for overload testing. 4)
A call was made for more dataset donations to the free database project. ---------------------------------------------------------------------------- Strain-Life
Fatigue Data Exchange File Format (Revised) 1)
Scope -- SAE data file format for a
SIMPLE Strain-Life Fatigue Data Exchange File Format.
The object of this SAE Standard is to provide a simple common way to
exchange strain-life fatigue data collected from ASTM E 606 axial fatigue test
data. 2)
References 2.1)
Applicable Publications 2.1.1)
ASTM Publication -- Available from ASTM, ASTM
E606-92(1998) -- Standard Practice for Strain Controlled Fatigue Testing 3)
A sample file that defines the format of the contents is depicted on the
following page: #
Proposed Fatigue Design & Evaluation Comm. Standard Strain-Life Fatigue
Exchange Data #File Format. # #
------------------------ #
Any line that begins with a # sign is a comment line, or an identifier line.
Blank lines can also # be inserted anywhere.
A comment can also appear at the end of a data line, or between data #
lines. #
------------------------ # #
A data line is assumed to be any line that is not a blank or a comment line. # #
Certain lines that begin with a #SYMBOL= VALUE, called tags, have special
meanings that # can be decoded by the receiving program.
Tag definitions are set out below. Curly
braces {} # with comma delimited values indicate the different values that may
be used with a tag. # Otherwise
character or numeric fields are required. The
units on strain values are absolute (no # percentages), and the stress units may
be defined as below. Tags should
begin in the first # column. # #
Use one or more "SPACE" characters to separate tags, values, and data
items. # #
*** MANDATORY TAGS ***
*** TAG
Explanation *** # #
#FileType= strain_life
# Define this
file type # #
#DataType= {raw,fitted}
# Experimental
data is indicated with a "raw", #
interpolated data with "fitted" # #
#NAME= #
Unique material identifier. Several
of #
these tags may be used in a single file. # #
#UNITS= {ksi,mpa}
# Stress units
used in the file need to be defined. # #
#E=
# Average Elastic
Modulus (measured from fatigue tests) # #
**OPTIONAL SUGGESTED TAGS** # #
#Sy=
# Monotonic Yield Stress # #
#Su=
# Monotonic Ultimate Stress # #
#%RA=
#
percent reduction in area at failure in monotonic test # #
#BHN=
# Hardness of material in the Brinell scale # #
#monotonic_K=
# strain hardening coefficient, K, for monotonic test # #
#monotonic_n=
# strain hardening exponent, n, for monotonic test # #
#FLAT=
# Flat top type yield stress (average value) # #
#FractureStrength=
# True Fracture Stress at failure (monotonic) # #
#FractureStrain=
# True Fracture Strain at failure (monotonic) # #
#MaterialForm=
# Raw form of material {e.g. plate, rod, bar, sheet, extrusion} # #
#SpecimenForm=
# Type of fatigue specimen {e.g. threaded_round,flat_dogbone} # #
Items whichs don't appear in tags but should be included in descriptive comments #
(such as this one) include material processing, microstructure, specimen #
orientation and other issues discussed in ASTM E606. #
**SAMPLE FILE **** : #FileType=
strain_life #
strain life type standard file #DataType=
raw
# "raw"= measured, as opposed to "fitted" #NAME=
SAE1045 #NAME=
SAE350X #NAME=
SAE050X #UNITS=
KSI #Su=
89. #Sy=
50. #E=
30000. #%RA=
85. #BHN=
325 #FLAT=
50. #monotonic_K=300. #monotonic_n=0.2 #FractureStrength=300. #FractureStrain=0.63 #MaterialForm=
bar #SpecimenForm=
round_dogbone #
Here is an example of a data point set. Note that a comment field can also be
appended to the #data field, or in between the data lines.
A data line is assumed to be any line that is not a blank #or a comment
line. The data should contain one
fatigue test per line, and on each line the fields #are separated by one or more
blanks. # #Strains
are to be reported in their "raw" dimensionless units (mm/mm = in/in) # #
Total Strain 2Nf
Stress Mean
Plastic Strain
Initial #
Amp
Amp Stress
Amp
Elastic Mod.
0.0125
180 279.
.0
0.0030
30100. # specimen
comment
0.0095
490
253. .0
0.0011
29400.
0.0090
950 229.
.0
0.0007
29800.
0.0075
2260 220.
.0
0.0002
30050.
0.0050
38000. 149. .0
0.0
29900.
0.0040
770000 119. .0
0
30700. #
Runouts or suspended test articles are denoted by a "#runout" appended
to the dataline: 0.0020
10000200 90.
0
0
30200. #runout #
or runouts can be denoted by a "negative" life: 0.0022
-20000200 98.
.0 0.0
29700. #
Other data point tags, for clarity, are at option of user
e.g.: 0.022
10
320. .0
0.0102
31100. #buckled
--------------------------------------------------------------------- Periodic
Overload Fatigue Data Exchange File Format 1)
Scope -- SAE data file format for
exchanging controlled periodic overload data. The
object of this standard is to provide a simple, common methodology for
exchanging the
data from periodic overload fatigue tests. These
tests consist of a single large fatigue
cycle followed by a larger number of smaller cycles.
The overloads are fully reversed
fatigue cycles while the smaller cycles share a common mean and amplitude. 2)
References 2.1)
Applicable Publications 2.1.1)
ASTM Publication -- Available from ASTM,
ASTM E606-92(1998) -- Standard Practice for Strain Controlled Fatigue
Testing 3)
A sample file that defines the format of the contents is depicted on the
following page. #
Proposed Fatigue Design & Evaluation Comm. Standard Periodic Overload Test
data file #Format. # #
------------------------ #
Any line that begins with a # sign is a comment line, or an identifier #
line. Blank lines can also be
inserted anywhere. A comment can #
also appear at the end of a data line, or between data lines. #
------------------------ # #
A data line is assumed to be any line that is not a blank or a comment line. # #
Certain lines that begin with a #SYMBOL= VALUE, called tags, have special
meanings that #can be decoded by the receiving program.
Tag definitions are set out below. Curly
braces {} #with comma delimited values indicate the different values that may be
used with a tag. #Otherwise
character or numeric fields are required. The
units on strain values are absolute (no #percentages), and the stress units may
be defined as below. Tags should
begin in the first #column. #
Use one or more "SPACE" characters to separate tags, values, and data
items. # #
*** MANDATORY TAGS ***
*** TAG
Explanation *** # #
#FileType= strain_life_overload #
Define this file type # #
#DataType= {raw,fitted}
# Experimental
data is indicated with a "raw", #
interpolated data with "fitted" # #
#NAME=
# Unique material
identifier. Several of #
these
tags may be used in a single file. # #
#UNITS= {ksi,mpa}
# Stress units
used in the file need to be defined. # #
#E=
# Average Elastic
Modulus (measured from fatigue tests) # #
**OPTIONAL SUGGESTED TAGS** # #
#Sy=
# Monotonic Yield Stress # #
#Su=
# Monotonic Ultimate Stress # #
#%RA=
# percent reduction in area at failure in monotonic test # #
#BHN=
# Hardness of material in the Brinell scale # #
#monotonic_K=
# strain hardening coefficient, K, for monotonic test # #
#monotonic_n=
# strain hardening exponent, n, for monotonic test # #
#FLAT=
# Flat top type yield stress (average value) # #
#FractureStrength=
# True Fracture Stress at failure (monotonic) # #
#FractureStrain=
# True Fracture Strain at failure (monotonic) # #
#MaterialForm=
# Raw form of material {e.g. plate, rod, bar, sheet,
extrusion} # #
#SpecimenForm=
# Type of fatigue specimen {e.g. threaded_round,flat_dogbone} # #
Items whichs don't appear in tags but should be included in descriptive comments #
(such as this one) include material processing, microstructure, specimen #
orientation and other issues discussed in ASTM E606. #
**SAMPLE FILE **** : #FileType=
strain_life_overload
# strain life overload type standard file #DataType=
raw
#
"raw"= measured, as opposed to "fitted" #NAME=
SAE1045 #NAME=
SAE350X #NAME=
SAE050X #UNITS=
KSI #Su=
100. #Sy=
60.0 #E=
29500. #%RA= 50. #BHN= 203 #XK= 200. #Xn= 0.25 #FLAT= 60.0 #FractureStrength=
250. #FractureStrain=
0.60 #MaterialForm=
bar #SpecimenForm=
round_dogbone #
General definitions of abbreviations #
SC =Small CYcle #
OL =OverLoad Cycle #
e =strain #
S =stress #
Amp = stress/strain amplitude associated with cycle #
Mean = average value of quantity #
Plastic e = plastic strain associated with cycle #
initial modulus = initial elastic modulus from first cycle #
Specific meanings of labels: #
SC Total e - small cycle strain
amplitude #
Fail Blocks - total number of block repetitions to failure #
SC per block - number of small cycles per block (assuming 1 overload/block) #
CA Life = Constant Amplitude Life of overload cycle in cycles #Strains are to be reported in
their native dimensionless units (mm/mm or in/in) # #
SC Fail
SC SC
SC
SC
SC OL
CA OL
OL OL
initial #
e Blocks
per S
Mean Mean
Plastic
e
Life S
Mean Plastic
elastic #
Amp
block Amp
e
S
e Amp Amp.
(Nf)
Amp S
e Amp modulus 0.00075
4347.7 10000
20.0 0.00390
36.0 0.0000625
0.00500 10000
60.0 0.0
0.00270 28371 0.0008
5000.0 5000
25.0 0.00380
34.0 0.0000500
0.00500 10000
60.0 0.0
0.00270 28593 0.0009
3000.1 500
27.0 0.00400
0.0 0.0000625
0.00500 10000
60.0 0.0
0.00280 31395 0.0015
2000 100
36.0 0.00000
0.0 0.0002200
0.00550 7000
65.0 0.0
0.00325 27896 0.002
1400.5 100 41.0
0.00000 -10.0
0.0005250 0.00500
10000 60.0
0.0 0.00280
30948 0.0025
1700
50 43.0
0.00250 20.0
0.0007500 0.00500
10000 60.0
0.0 0.00280
29346 #buckled? #no recorded stress data?: 0.00125
1300
250 0.0
0.00550 0.0
0.0001400 0.00650
5000 68.0
0.0 0.00400 727943 #Suspended test articles are
denoted by a "#runout" appended to the dataline 0.00070
4347.7 50000
17.0 0.00390
36.0 0.000025
0.00500 10000
60.0 0.0
0.00270 29375. #runout Respectfully
submitted, John
Bonnen Chairperson,
Life Prediction Division |
