Vibration testing determines the dynamic effects on component part of vibration within the frequency ranges and magnitudes that may be encountered during field service. Vibration, for example, causes loosening of parts or relative motion between parts in the specimen, producing objectionable operating characteristics, noise, wear, and physical distortion, and often results in fatigue and failure of mechanical parts.
Vibration testing is classified into four main categories, as follows:
This test verifies that material can physically and functionally withstand the relatively infrequent, repetitive sustained vibration encountered in operational environments during the firing of various armaments.
This test is characterized by irregular non-repeating patterns and amplitude, versus time. Random vibration more closely simulates the dynamic conditions in the real world than sinusoidal vibration.
This test is characterized by vibration amplitudes which vary sinusoidally with time such as generated by rotating machinery.
Vibrations are produced simultaneously, to simulate environments where combinations of the above are present, in the actual environment. Mixed mode vibration has been shown to more often simulate the real world environment than either sine or random vibration separately.
Vibration testing is specified in the following:
MIL-PRF-27, MIL-T-27, MIL-STD-167-1, MIL-STD-202, MIL-J-641, MIL-STD-750, MIL-STD-810, MIL-STD-1621, MIL-STD-3885, MIL-E-5272, MIL-E-5400, MIL-T-5422, MIL-T-7743, MIL-F-7872, MIL-T-7928, MIL-M-7969, MIL-A-8064, MIL-K-8144, MIL-E-8189, MIL-R-8236, MIL-C-8384, MIL-F-8615, MIL-S-8805, MIL-V-8813, MIL-A-8870, MIL-M-10304, MIL-C-11015, MIL-R-11050, MIL-R-11539, MIL-C-11693, MIL-C-12889, MIL-R-12934, MIL-C-13486, MIL-F-13926, MIL-C-14409, MIL-R-15109, MIL-C-15240, MIL-C-15305, MIL-F-15733, MIL-P-15736, MIL-S-15743, MIL-S-16036, MIL-F-16377, MIL-E-16400, MIL-V-16556, MIL-R-16999, MIL-T-17113, MIL-T-17185, MIL-M-17185, MIL-T-17275, MIL-T-17293, MIL-V-17361, MIL-V-17456, MIL-V-17547, MIL-V-17639, MIL-P-17840, MIL-V-17840, MIL-P-17869, MIL-V-18110, MIL-F-18327, MIL-T-18404, MIL-P-18472, MIL-H-18766, MIL-I-18997, MIL-F-19004, MIL-M-19097, MIL-E-19100, MIL-N-19900, MIL-R-19648, MIL-M-19160, MIL-I-20037, MIL-S-20708, MIL-C-21097, MIL-T-21200, MIL-D-21625, MIL-V-22052, MIL-V-22133, MIL-C-22317, MIL-S-22432, MIL-C-22437, MIL-H-22594, MIL-V-22687, MIL-D-22706, MIL-R-22732, MIL-S-22885, MIL-A-22895, MIL-B-23071, MIL-A-23836, MIL-L-23886, MIL-P-23928, MIL-E-24091, MIL-E-24142, MIL-L-24223, MIL-P-24423, MIL-V-24509, MIL-T-28800, MIL-E-39029, MIL-H-83511, MIL-S-008834, MIL-T-0014358, UL-213, UL-886, UL-1474, US COAST GUARD NO. 493, ISO-10055, ISO/FDIS 15540, ISO-15541, RTCA/DO-160, NAVMAT P-9492, GR-487-CORE, ASTM E-644-91, ASTM F1387-99, ASTM D-999-68, IEC 68-2-6, ISTA, MIL-T-0014358, MIL-S-008834, SCL-7695, SCL-7722
The vibration/acoustic/temperature procedure is performed to determine the combined effects of vibration, acoustic noise, and temperature. A typical example of items tested are aircraft equipment such as externally carried stores.
Vibration/acoustic/temperature testing is specified in the following: