Safe and accurate dosing of solvents

Thin and watery liquids with instructions for use

Solvents such as acetone, toluene, alcohols and ether are indispensable in the chemical, pharmaceutical and process industries. At the same time, they are among the most difficult liquids to handle. Without the correct equipment, their low viscosity, non-lubricating nature and rapid evaporation can quickly lead to wear on plain bearings or seals, loss of capacity or unsafe conditions in the workplace.

Three factors play a key role in the safe and accurate dosing of solvents and other low-viscosity liquids:

Lubricating properties: Many thin liquids have virtually no lubricating properties, which places additional demands on the material and design of pump components such as plain bearings and (shaft) seals
Vapour pressure and cavitation: As soon as the pressure in the pump casing falls below the vapour pressure of the liquid, gas bubbles form. This causes vibrations, damage to the internal components and dosing deviations
Safety and emissions: Leaks of volatile or flammable substances are strictly prohibited, both because of stricter environmental legislation (such as TA-Luft and ATEX) and for the safety of staff

Gear pumps built for precision

To transfer these fluids with the utmost precision, a pulsation-free and consistently performing flow is essential. Gear pumps offer the ideal solution here. Thanks to their volumetric operation, they continue to dispense with precision, even when handling fluids with a viscosity significantly lower than that of water.

Our gear pumps have been specifically developed and designed for this type of critical application:

Advanced sealing and plain bearing technology: A choice of high-quality mechanical seals, magnetic couplings or special gaskets that guarantee liquid and vapour tightness. Special internal flushing channels to ensure that the lubricating film is maintained
Wear-resistant material combinations: Bearings and shafts made from specially selected materials (such as silicon carbide, zirconia or specific alloys) prevent wear, even when used with fluids that lack lubricating properties
Pulsation-free and precise dosing: Immediate and continuous output ensures high-quality process control without fluctuations

Tailor-made solutions for your process
No two processes are identical. The exact temperature, pressure, viscosity and chemical composition determine the ideal pump configuration. At Suurmond, we combine decades of application expertise with high-quality gear pumps to deliver bespoke solutions that seamlessly meet your process requirements.

Parameters for low-viscosity liquids

Differential pressure	max 80 bar (depending on the viscosity)
Viscosity	from 0.2 mPa·s
Temperature	min -50°C max 450°C
System pressure	max 325 bar

Examples of applications for our gear pumps

Acetone
Toluene

Alcohols
Ether

Frequently Asked Questions:

: Low-viscosity (thin) liquids, such as solvents, flow easily back past the moving parts of a pump (internal volumetric loss or slip).

As a result, output can vary significantly when back pressures fluctuate. Gear pumps compensate for this through very tight tolerances and a constant volumetric displacement, ensuring that the dispensed volume remains exactly the same.
: Volatile substances have a high vapour pressure and evaporate rapidly when the pressure in the pump drops. This leads to cavitation (gas bubbles that implode and damage the pump).

To prevent this, we ensure a favourable inlet geometry (an extremely low NPSHr value for the pump), the correct speed and an optimally sized suction pipe.
: Standard pumps rely on the fluid being pumped to lubricate the bearings. For low-viscosity and/or non-lubricating fluids such as alcohols or acetone, we use special material combinations for the bearings and shafts (such as silicon carbide, zirconia, carbon graphite or specific coated alloys) that do not require fluid lubrication to prevent wear. Furthermore, special internal flushing channels are provided to ensure that the lubricating film is maintained.
: Depending on the material, temperature and ATEX zoning, we opt for:

Magnetic couplings (hermetically sealed, leak-free): Liquid- and vapour-tight without a dynamic shaft seal, using only static seals, which reduces the risk of leakage to zero.

Double mechanisalhe seals: Featuring a flushed pressure-seal system to prevent the escape of harmful vapours.
: Yes. As solvents and volatile liquids are often highly flammable, Suurmond’s pump units can be supplied fully ATEX-certified (Zone 1 or Zone 2), including suitable motors, earthing and temperature monitoring.
: That is certainly possible, provided that the materials (housing, gears, bearings and seals) are chemically resistant to all the fluids used. Our specialists select the required configuration of chemically resistant materials based on the specific fluid or mixtures in question.