Dosing highly viscous liquids: getting exquisite results with viscous media

One important property of liquids is their viscosity and many pumps will struggle with highly viscous media. When bottling honey, it is typically heated moderately to reduce its viscosity, a principle applicable also to many other highly viscous liquids. If an increase of the liquid temperature is not suitable, pumps with a high engine performance will be required. KNAUER pumps with their powerful motor drives are adequate for these demanding conditions.

Pump requirements

  • High delivery pressure
  • Reliable and easy to maintain
  • Handling of high viscosity fluids

Pump features

  • Engineered for durability and built with high quality components and materials
  • High engine performance for highly viscous media
  • Capability to meter liquids with viscosities up to 1000 mPa·s
  • Constant flow operation mode
  • Wide flow rate range and large dynamic range
  • Additional pump head heating device can be used to reduce the viscosity of the liquid
  • Flexible control due to a range of supported interfaces (RS232, Ethernet and analog)

Application examples

  • Metering of polymers
  • Metering of polyols and isocyanates

Operating parameters

Max. delivery pressure40 MPa (400 bar, 5800 psi)
Flow rate range0.01–1000 ml/min
Max. viscosity1000 mPa·s
Liquid temperature range

20–60 °C (68–140 °F)

Selected KNAUER pumps for dosing highly viscous liquids

Max. flow ratePump head materialPump type

BlueShadow 80P

100 ml/min

stainless steel

BlueShadow Pump 80P APD20KA


BlueShadow Pump 80P APD20KB

250 ml/min

stainless steel

BlueShadow Pump 80P APD20LA


BlueShadow Pump 80P APD20LC

500 ml/min

stainless steel

BlueShadow Pump 80P APD20MA


BlueShadow Pump 80P APD20MC

1000­­ ml/min

stainless steel

BlueShadow Pump 80P APD20NA


BlueShadow Pump 80P APD20NB