We perform the random vibration test on a vertical electrohydraulic vibration machine equipped with computerized controls. To perform this test, we use the following procedures.
1. Program the vibration system to reproduce three consecutive sequences of random vibration profiles representing the FedEx distribution environment as indicated in the spectra profiles.
• Truck vibration at 0.52 Grms (profile one).
• Air vibration at 1.06 Grms (profile two).
• Repeat truck vibration at 0.52 Grms (profile one).
2. Set the duration of each sequence at 15 minutes forU.S. shipments, 30 minutes for international shipments.
3. Place the test package on the vibration table. Fixturesmay be used during testing to prevent the package from moving off the table, to prevent unsafe conditions or to maintain test orientation without restricting the vertical movement.
4. Load the appropriate automatic sequences of random
We perform the rotary vibration test on a mechanicalrotary vibration machine. The machine will vibrate at 1.0" total displacement. Packages will be subjected to a total of 14,200 vibratory impacts. Fixtures or restraintsmay be used during testing. To perform this test, we use the following procedures.
1.Place the package on the vibration table and begin the vibration cycle at a running speed of approximately237 cycles per minute.
2.Stop the vibration test after 30 minutes (7,100impacts). Maintain the orientation and turn the package 90 degrees on its face.
3.If package size or shape does not permit 90 degreehorizontal rotation, rotate the package 180 degreeshorizontally.
4.Start the vibration machine for the remaining 30 minutes. Flat and elongated packages will be vibrated on theirsmallest and largest surfaces respectively.