Liquid Handling, Pumps & Fluid Control

Start with what the fluid demands rather than the flow rate alone. Shear sensitive or sterile media favour peristaltic heads because only the tubing touches the liquid, while aggressive solvents suit sealless diaphragm designs. High volume thin liquids move well through centrifugal pumps, and precise low volumes call for a syringe drive. Match the wetted materials to your chemistry before comparing throughput.

Look closely at the parts that contact the fluid, since seals, diaphragms and tubing wear first. Ask the seller whether these were replaced recently and whether the drive holds its set flow across the range. Check that the motor runs without excess noise or vibration, which points to bearing wear. A recent service record gives you confidence that the unit is ready to run.

Peristaltic pumps are the usual answer for aseptic work because the fluid stays inside disposable tubing that you can autoclave or replace. Diaphragm pumps with sterilisable heads also suit clean transfer where the membrane is the only wetted surface. Confirm that the tubing size and material match your validation requirements. The seller can tell you which heads and tube grades a given unit accepts.

Size the pump around your working point rather than its maximum figure, as pumps run best near the middle of their range. Note the volume you move per run and the back pressure from filters, fittings and vertical lift. A unit that just reaches your target will struggle, so leave headroom. Share those numbers with the seller and they can confirm the model suits the duty.

Financing is available on qualifying listings, which lets you spread the cost of a larger platform such as an automated pipetting system. You raise it with the seller during your enquiry and they confirm whether their listing qualifies. This keeps working capital free while you bring the equipment into service. Terms depend on the item and the seller.