A new sound testing chamber at Eaton Corp.'s Hydraulics Operations facility, Eden Prairie, Minn., is designed to meet the needs of low-noise hydraulic components and systems.

The state-of-the-art hemi-anechoic chamber's primary functions include:

  • Validating acoustic Boundary Element Method (BEM) models and benchmarking competitive components
  • Providing complete noise and/or vibration testing of hydraulic components, integrated systems, and customer applications (vehicles)
  • Testing per industry standards (ISO, NFPA, DIN, GM, etc.)
  • Supporting customer-specific noise, vibration, and harshness (NVH) issues

Perception of noise directly influences customer acceptance of Eaton products, explained Mike Beyer, technical specialist - NVH. "Both mobile and industrial markets demand low-noise components and systems in efforts to maintain a competitive advantage in a constantly evolving global arena," Beyer said.

"The overall noise level of our piston pumps, vane pumps, and steering control units is the parameter that is documented in product literature, but it's the customer's perception of sound quality that is the true measure of perceived product quality."

Beyer continued, "The sound chamber is a critical component in our methodology for low-noise design and increases customer confidence in our ability to design and develop hydraulic components that are inherently quiet, thereby illustrating our commitment to the future of hydraulics.

"It also enables us to validate models and benchmark other companies' products, which is critical in supporting our strong emphasis on NVH modeling and simulation efforts."

The sound chamber lets Eaton rank noise levels in general on customer vehicles, as well as provide noise reduction solutions outside the realm of hydraulic components, which, in most applications, are not the leading contributor to the overall noise of mobile and industrial equipment.

The internal dimensions of the hemi-anechoic chamber (meaning all but the floor is sound-absorbing) accommodate vehicles up to nearly 19 ft long, 8 ft wide and 12 ft high. The chamber is certified to an 80-Hz cut-off frequency and provides 600-hp drive capability.