Mechanical Technology June 2015

⎪ Pump systems, pipes, valves and seals ⎪

Extensive gear pump range for viscous fluids T he Viking range of internal gear pumps continues to sell steadily into South Africa through local distributor Mather+Platt’s Viking range of gear pumps is extensive, comprising six distinct lines.

C-flange-mounted pumps in eight sizes are made from cast iron for medium- duty applications, and these do not require speed reducers either. For applications in which leakage and fugitive emissions must be eliminated, or where downtime for seal maintenance would be problematic, there are mag-drive pumps in 12 internal gear and 22 external gear sizes, which replace shaft seals with magnetic drives. Mather+Platt can custom build Viking pumps for special applications. Examples include abrasive liquid pumps with hard- ened construction and silicone carbide seals, and ammonia pumps with double mechanical seals, pressurised seal cham- bers and oil reservoirs, lubricated idler bushings, and adjustable return-to-tank bypass valves. q

Mather+Platt, which reports that carefully maintained local stock holdings are helping to secure urgent orders. Wadeville-based Mather+Platt has distributed Viking pumps for more than 20 years. Viking is widely recognised as one of the world’s leading manufacturers of positive displacement pumps such as internal gear pumps, external gear pumps, vane pumps and rotary lobe pumps. In South Africa, these pumps are widely used in mining and industrial applications, where they transfer viscous fluids with viscosities of up to 440 000 cSt. The pumps have applications in petro- chemical processing (bitumen, pitch and viscous oils), chemical processing (sodium silicate, acids, plastics, paints, resins, adhesives and mixed chemicals), pulp and paper (acids, soap, lime, kaolin and sludge), and the food industry (chocolate, butter, fillers, molasses and vegetable fats). The internal gear pumping principle, invented by Viking Pumps’ co-founder Jens Nielsen, uses two rotating gears, which un-mesh at the suction side of the pump to create a vacuum, which pulls fluid into the pump. The spaces between the gear teeth transport the fluid on either side of a crescent to the discharge side, where the gears re-mesh to discharge the fluid.

There are universal seal pumps in 12 sizes, comprising heavy duty, foot-mounted models with enlarged bearing housings that allow seals and seal technologies to be exchanged without removing the pump from the flow line. Materials of manufacture include stainless steel, steel, ductile iron and cast iron. High-speed compact pumps in six sizes are recommended for medium- to heavy- duty applications. No speed reducer is required and materials of manufacture are as for universal seal pumps. Motor speed pumps in six sizes are manufactured in ductile iron, and may be foot-mounted or close-coupled to IEC frame motors for a compact footprint. General- purpose foot-mounted pumps in 14 sizes are made of cast iron for medium duty ap- plications. Jacketing options are available.

Some of the Viking range gear pumps.

Mechanical Technology — June 2015

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