Viking internal gear pumps are extraordinarily versatile. While they are often used on thin liquids such as fuel oil and solvents, they excel at efficiently pumping thick liquids such as chocolate, asphalt and adhesives. The useful viscosity range of an internal gear pump is from 1cPs to over 1,000,000cP.

In addition to their extensive viscosity range, the pump has a wide temperature range as well, handling liquids up to 750F/400C. This is due to the single point of end clearance (the distance between the ends of the rotor gear teeth and the head of the pump). This clearance is adjustable to accommodate high temperature, maximize efficiency for handling high viscosity liquids, and to accommodate for wear.

The internal gear pump is non-pulsing, self-priming, and can run dry for short periods. They’re also bi-rotational, which means that the same pump can be used to load and unload vessels. Because Viking internal gear pumps have only two moving parts, they are reliable, simple to operate, and easy to maintain.

How Viking Internal Gear Pumps Work

1. Liquid enters the suction port between the large exterior gear and small interior gear teeth. The arrows indicate the direction of the liquid and pump.
2. Liquid travels through the pump between the teeth of the “gear-within-a-gear” principle. The semicircular shape divides the liquid and acts as a seal between the discharge and suction ports.
3. The pump head is now nearly flooded, just prior to forcing the liquid out of the discharge port. Intermeshing gears of the idler and rotor form locked pockets for the liquid which assures volume control.
4. Rotor and idler teeth interlock completely to form a seal equidistant from the discharge and suction ports. This seal forces the liquid out of the discharge port.

Advantages of Viking Internal Gear Pumps

  • Only two moving parts and one stuffing box
  • Non-pulsating discharge
  • Excellent for high-viscosity liquids
  • Constant and even discharge regardless of pressure conditions
  • Operates well in either direction
  • Can be made to operate with one direction of flow with either rotation
  • Low NPSH required
  • Single adjustable end clearance
  • Easy to maintain
  • Flexible design offers application customization

Applications for Viking Internal Gear Pumps

Common internal gear pump applications include, but are not limited to:

  • All varieties of lube oil and fuel oils
  • Resins and Polymers
  • Alcohols and solvents
  • Asphalt, Bitumen, and Tar
  • Polyurethane foam
  • Food products such as corn syrup, chocolate, and peanut butter
  • Paint, inks, and pigments
  • Soaps and surfactants
  • Glycol

With the wide variety of pumps available today, it’s sometimes difficult to know which is best for your particular application. Which pump can handle the viscosity of the fluid or generate the proper flow and pressure?

To be certain you are getting exactly what you need, it’s a good idea to consult with an engineer well versed in Viking internal gear pumps. Call our office today and let our experts help you choose. And keep in mind that we also offer engineering services and parts and repairs to keep your business running smoothly.