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Laboratory Evaluation of ASTM D4169 (Current and Proposed) Vibration Profiles
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Figure 2.1: Power Spectrum Density Plot Of All The Profiles Used In The Study
PSD
(g
2
/Hz)
10
-1
10
-2
Current ASTM
Proposed ASTM - High
Proposed ASTM - Med / ISTA Steel
Spring
Proposed ASTM -
Low
10
-3
10
-4
10
0
10
1
10
2
10
3
Frequency (Hz)
Test Sequence
A (Low)
B (Medium)
C (High)
Loop
Overall Grms
0.40
0.54
0.70
Proposed Test Time
(Minutes)
120
45
15
180
180
Total Loop Time
1- Loop
Table 2.3: Modified 1 - Proposed ASTM D4169 Profile One Cycle of 180 Minutes
Test Sequence
B (Medium)
C (High)
Loop
Overall Grms
0.54
0.70
Proposed Test Time
(Minutes)
45
15
60
60
Total Loop Time
1 Total Loops
Table 2.4: Modified 2 -Proposed ASTM D 4169 Profile (Medium &High) for 60 Minutes