In-Place-Dynamic Sound Power Test Method

ISO and SAE static sound power test methods are currently used for construction machinery. The European Economic Community sound committee has been developing a drive-by or simulated work cycle test method using a hemispherical array of microphones. The EEC method is inconsistent due to the changing test surface (moist sand) and the variables of outdoor testing: temperature, wind, and precipitation. The in-place-dynamic test method described provides a disciplined way to evaluate machines with moving track or wheels and operating hydraulic systems. The machine is slightly elevated, resting on stands, so that the wheels are off the ground or the tractor weight is off the track chain. Data obtained from track-type tractor, track-type loader, and wheel loader machines supports the validity of using an indoor, in-place-dynamic test instead of a moving, outdoor test. Results also show that using sound intensity instrumentation permits the option of testing in an untreated, indoor facility.