Parmalat Dairies (UK)
Special mechanical seal allows pump flow to be reversed

Dirk Mucha, seepex

At Parmalat Dairies in the UK, a hygienic progressing cavity pump has been in operation since the mid 1990s, handling quark. Its reliable performance - it has never broken down in that period - and the fact that it had required very few replacement parts, led Parmalat to ask its manufacturer to consider another pumping problem they were facing.

The Kendal plant manufactures fresh yoghurt for many of the UK’s major multiples. Parmalat required a compact pumping system to feed yoghurt into a mixing vessel where the processed fruit is added, and then pumped it out again to the filling lines. “What seepex came up with was really two pumps for the price of one”, says Hugh Wilkinson, the site Maintenance Manager. The seepex CS progressive cavity pump “not only pumps the plain yoghurt in, but also out again, once we’ve added the fruit, and all using the same pump.” This bi-directional flow is achieved by the fitting of a special mechanical seal which allows the pump flow to be reversed with the shaft rotation - adding to the versatility of the seepex solution.

Specifications
The CS pumps meet the highest standards for gentle handling, sanitation, cleaning and sterilization in place. The capacities range from 30 l/h up to 130 m³/h at pressures up to 24 bar. Dependent on the specific application from three ranges can be chosen.
The first range (BCSO) is equipped with open “hygienic” universal joints. With CIP- (Cleaning In Place) flushing, a residue-free cleaning is ensured. They fulfill the highest demands for hygienic cleaning and resistance to corrosion and wear. Beside the special design of coupling rod and rotor or plug-in shaft end the open fork joint consists of only two components, the pin and the circlip. A new developed open pin joint now allows higher pressures and flow rates. Service work can be performed easily and quickly without tools. Pumps of the second range (BCSO) meet the specifications of the 3A-Sanitary Standards of the US and the EHEDG regulations. The third range (BCSB) pumps are furnished with cost efficient pin joints and are especially suited to highly abrasive products and high operating pressures. Like the BCSO pumps, range BTCS pumps are equipped with maintenance friendly sanitary joints. These pumps are offered with an auger feed screw and an open inlet hopper with cylindrical compression zone suited for conveying highly viscous products.

CIP-able
Parmalat states the CS pumps to be ideally suited to handling sensitive dairy products. The pump has a gentle, low shear pumping action and can pass large solids such as berries and fruit pieces without damage. “Achieving 100% of what they have promised to date, we are now considering this manufacturer for a further, larger, pump installation” concludes Parmalat’s Wilkinson. With the pumps being CIP-able and with the added advantages of low pulsation and constant flow, irrespective of product or process changes, seepex hygienic pumps are designed to meet precisely the needs of the production environment in today’s food and drink industries. <<