Did you know that pumps are needed to produce the world’s most decadent milk, white, and dark chocolates? While people around the globe enjoy chocolate in all its glorious forms, industrial professionals often face challenges pumping chocolate.
The problems with pumping chocolate
The internal parts of pumps often block when pumping chocolate. This is due to a temperature increase in the pump, which caramelizes the chocolate, causing it to congeal. As more and more chocolate congeals, the internal friction in the pump is increased, and a vicious circle starts, which ends ultimately when the pump blocks completely. This is particularly true when pumping chocolate under relatively high pressure.
To address these pumping problems, DESMI collaborated with leading chocolate manufacturers to become the leading chocolate pump manufacturer for the past 49 years, having engineered a unique gear pump that meets the high requirements for the careful pumping of chocolate – both in mechanical and temperature terms.
The DESMI ROTAN® internally toothed gear pump focuses on the problems often encountered with pumping chocolate. The internal tolerances of the ROTAN® pump have been designed in such a way that ”new” chocolate is always added to the areas around the rotating parts of the pump, and in particular, around the pivot of the star wheel and bushings. This reduces, or eliminates, the tendency for the chocolate to caramelize on the back of the rotor and at the bearing of the star wheel, therefore preventing the pump from blocking.
The illustration above shows how the gear pump with internal toothing results in almost no change in the flow direction through the pump, making this type of pump particularly well-suited for pumping chocolate.
In addition, ROTAN® has developed a combination of sealing and main bearing, which is unique to this type of pump. A packing cord mounted between the pump casing and main bearing greased externally with cocoa butter prevents heating and caramelizing in this area.
As shown above, a special main bearing with a lip seal keeps the lubricant within the pump. The added lubricant lubricates both the main bearing and the packing cord. This reduces friction and thereby the temperature of the bearing and packing cord.
ROTAN® CHD (chocolate) pumps have heating jackets fitted to the front and rear end as standard. Special tolerances entail ‘rinsing’ around the rotating parts and the bearing area, thereby preventing blockage of the pump.
The characteristic ”back pull-out” system allows inspection and repairs without dismantling the pump, which reduces maintenance and downtime considerably!
Read how the ROTAN® pumps help Kinnerton process 77 million pounds of chocolate, Review the ROTAN® Pump Performance Chart, or Learn more about pumping dark, milk, and white chocolate!