The OSB ring seal has been designed to stop chocolate (and other similar foods) from leaking out along the pump shaft.
The OSB ring seal has been designed to stop chocolate (and other similar foods) from leaking out along the pump shaft.

The latest addition to the Viking Pumps’ range of cast iron internal gear pumps features a new seal modification developed specifically for pumps used in chocolate processing and similar applications.

The pumps are supplied by Michael Smith Engineers and the new seal modification has an O-Ring Seal Bushing (OSB), which is effectively a combined bracket bushing and seal gland, with double O-ring seals, housed in a cast-iron cylinder and with back pull-out accessibility.

The OSB ring seal has been designed to fit all the pumps in Viking’s Universal Seal Series with the specific aim of keeping chocolate (and other similar foods) from leaking out along the pump shaft. The static O-Ring seals between the OSB and the bracket prevent leakage outside of the OSB, whilst the area between each set of inner and outer rings is filled with food-grade grease to provide lubrication and act as a double seal barrier to prevent leakage along the shaft.

The OSB keeps chocolate out of the bracket, eliminating a key area of chocolate entrapment. The pump casing features flush and suck back grooves which creates flow behind the pump rotor, preventing solid product build-up.  The CHC Series pumps also incorporate a drilled idler gear with hard cast-iron bushing and special internal clearances to prevent chocolate caking and build-up.