In an airplane factory, noise from riveting produces short-duration, high-amplitude sounds with high-level components at frequencies where the human ear is most sensitive. High-pressure air exhausted from air-powered tools is another prevalent noise source in airplane manufacture and repair and can be a major contributor to a worker's daily exposure to noise. Control of the impulsive sound of riveting without affecting production was achieved by developing a new way to apply constrained-layer damping pads to the skin of an aluminum panel. A pad is held against a panel by a vacuum pressure about 90 kPa. The time-average, A-weighted sound level at a position representative of the ear of the operator of a riveting hammer was reduced by about 5.5 dB by application of the damping pads. Compressed-air tool-exhaust noise was reduced by multi-cavity mufflers consisting of reactive (tuned), resistive, and dispersive elements. The total 8-hour-average A-weighted sound level was reduced from approximately 93 dB to approximately 85 dB at the location of a worker exposed to the noise from tools powered by compressed air.
Case history: Noise control in airplane manufacturing
Eine Fallstudie: Lärmminderungsmaßnahmen in der Flugzeugproduktion
Noise Control Engineering Journal ; 44 , 4 ; 193-199
1996
7 Seiten, 8 Bilder, 4 Tabellen, 2 Quellen
Aufsatz (Zeitschrift)
Englisch
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