A manufacturing plant contacted Unger Technologies to review noise exposure from
several of its variable frequency belt driven centrifugal fans.
We conducted sound level readings around the Chicago Blowers and noted low and
mid frequency levels between 90-91 dB(A) 5 feet from the fans.
Our client expressed a need to access the machines for routine maintenance. They
also did not desire a full sound enclosure because of ventilation and lighting
concerns.
Blower
casing shown with Unger's removable sound blanket (click image for
larger view)
Fan shown with
sliding access sound curtain (click image for larger view)
Modular sound curtains used on
double sliding track (click image for larger view)
Unger determined noise sources associated with this fan where the variable speed
driven motors and the fan casings. The variable speed drives where re-tuned by
the equipment supplier with little reduction in noise. After this option was
tried, Unger suggested a removable sound blanket wrap be installed on the fan
housing and then a perimeter sound curtain system be installed.
We supplied our rugged industrial sound curtains with a ceiling suspended steel
track. We engineered modular sliding sound curtain panels on a double track to
allow the customer multiple access points in the enclosure.
The sound reduction was measured at 12 decibels thus achieving the customers
acoustic goals well below 85 dBA.
