Vibratory Iso-Finishing of Larger Gears and Engine Components

Contributed by Jim Riley, Technical Director, BV Products, Victoria, Australia

For additional information contact Dave Davidson at Senior Technical Advisor at Deburring/Finishing Technical Group (email) ddavidson@deburring-tech-group.com Tub or Trough style vibratory equipment ranges in size from 1 cubic foot [30 L] capacity up to 200 cubic feet [6000 L]. Tub vibrators are considered to have more aggressive media action than round-bowl machines, and they are capable of processing very large, bulky parts (as large as 6 ft by 6 ft) or potentially awkward part shapes (parts 40-ft long and longer). The vibratory motion generators consist of rotating shafts with sets of eccentric weights attached either at the bottom of the U-shaped tub or one of the sidewalls. This equipment is usually loaded from the top of the chamber and usually unloaded through a discharge door located on a side panel. Parts and media can be screened on an external separation deck. This arrangement allows for relatively quick load/unload or media changeover cycles when compared with other equipment. Tub-shaped or tubular-shaped vibrators are commonly utilized for continuous high volume applications where the time cycle required to process the parts is relatively short. Media return conveyors and feed hoppers are used to meter the correct ratio of media and parts to the loading area of the machine, while media and parts are separated on a continuous basis by a screen deck located at the unloading or discharge area of the machine. Tub-type machinery is also used extensively for batch applications and can be easily sub-compartmentalized for parts that require total segregation from each other.

This type of equipment lends itself to Isotropic Finishing of larger and heavier gear and drive train components found in the automotive and aerospace industries. This chemically accelerated method is used widely for the super-finishing of these types of cooperating components to improve their performance and service life.

Above is shown a BV Products Tub style (One of the VT-SF series) that has been configured to process larger, longer or heavier components. In some Isotropic Finishing applications, it can be useful to fixture parts in the media mass. this is a force multiplier and magnifies the force of the part is acted upon by the finishing media. The equipment shown is a tub-style vibratory machine and accommodates part lengths and sizes that would be impractical for a round bowl-shaped vibratory finishing machine. Photo Credit: BV Products

The above video shows the Isotropic Super-Finishing of a heavier shafted gear component in a tub or trough-shaped vibratory finishing with a fixturing accessory.