Transferring Water Based Paint at Specialist Coatings Manufacturer using Diaphragm Pumps

Coating Application & Use

Coatings are applied to a surface in layers and once dry they provide a film to protect it, for example from sunlight, corrosion, or water damage. These surfaces can be either metal, wood or plastic depending on the nature of the paint used. The industry considers a viscosity of around 100cp to be optimum for spraying, brushing, or rolling, this viscosity level guarantees a film that is thin, robust, and elastic.

A diluent is added to the paint to maintain the correct viscosity level, it can be either water-based, or solvent-based depending on the product. Water-based paints have become more common in recent times as they are more environmentally friendly; the diluent reduces the emission of solvents and ensures that only water vapour is released, therefore causing no damage to the environment. In addition to this, water-based coatings are non-flammable, have no odour and have low viscosity levels, all round they are a friendlier and safer product.

There have been great advancements in water-based paint technology and manufacturers have begun to produce high performance specialist coatings that would have previously been solvent based. Not only does solvent-base paint pose more risk, but it also requires more specialist paint pumps, typically involving stainless steel material and Atex class certification.

Paint Dispensing Requirement

We worked closely with a specialist coating manufacturer that supplies their products across a wide range of industries, they produce their water-based emulsions in bulk tanks and required 3 pumps to transfer the finished product into smaller containers varying from 25 litres to 1000 litre IBCs.

They need to vary the flow rate easily depending on the size of the container, a low flow rate is required when filling smaller containers to avoid splashing. Another requirement was for the pumps to be self-priming as sometimes it is not possible to gravity feed the inlet, it is also likely that dry running is possible as the operator can leave the unit unattended for periods of time when larger vessels are being filled.

The logical choice for this application was our Boxer 50 air operated diaphragm pump, this unit meets all their requirements in terms of performance and features. The flow rate is easily adjusted by simply altering the air pressure into the motor, the patented anti-stall motor allows for very low flow rates to be produced from the pump without stalling the motor and stopping production. This feature is extremely useful for filling their small containers, they can then simply open the air valve to increase the motor speed when filling larger vessels.

Why use an AOD Pump?

Our AOD pumps are enormously versatile in other ways also, they can self-prime, run dry without damage, produce up to 8 bar pressure, handle solid particles and transfer both low viscosity and high viscosity fluids with ease. We produced these units with polypropylene bodies and PTFE diaphragms for compatibility with the coatings, however we can manufacture the components in various materials to suit a wide range of fluids, even solvent-based paints if required, these include PVDF, aluminium, stainless steel 316, EPDM and NBR. Diaphragm pumps are Atex Zone 2 rated as standard for use in non-safe areas, however we can also produce them in special Atex Zone 1 versions for use with flammable liquids.

The factory operatives now have a reliable, flexible, and safe solution for pumping their paints. It is simple for them to move the pumps around site as they are lightweight, they can also easily swap container size and quickly alter the flow rate as and when required. There is peace of mind that this design will not be damaged from dry running when they are filling large tanks and leave them unattended to perform other tasks.

Below is the specification of the AODD pumps that were supplied: