KNF pumps measuring fine particulates from the back of a Google Street View car
FP 400: KNF’s New Low-Pulsation Diaphragm Pump
All the advantages of diaphragm pump technology plus the low pulsation of gear pumps
The FP 400 is a new generation of diaphragm pump from KNF combining the traditional advantages of diaphragm pump technology – it is self-priming, can run dry, and has a long service life – with a pulsation level comparable to that of gear pumps.
This next-generation pump has been specially designed to meet the challenges posed by UV inks, which are currently witnessing substantial growth across a range of applications in industrial inkjet printing (IJP). The five diaphragms of the FP 400 subject UV inks to minimal shearing forces, thus avoiding premature curing – i.e. activation of the UV initiators – inside the pump.
The new FP 400 delivers 4 to 5 l/min (depending on the version) to meet the higher recirculation volumes required by modern printers, which utilize a greater number of printheads (up to 36) per color bar. These new larger printers are used for packaging, laminates, textiles, wallpaper, ceramics, glass, metals and wood, among other products. Furthermore, the FP 400 is ideally suited to the new high laydown printheads on the market, which require much higher recirculation flow rates.
The FP 400 is available with a choice of different materials for compatibility with different ink types:
• An EPDM version for less aggressive UV and water-based inks
• A PFTE-coated diaphragm model, primarily for solvent-based inks
• A version with FFKM diaphragms and valves for oil/solvent-based inks and the abrasive pigments used in ceramic and glass printing
Low pulsation is a key feature of the new FP 400 – it achieves values lower than 150 mbar (at the pump outlet) at the nominal flow rate, and lower still with the right system configuration and running speed. In this respect, the new FP 400 performs just as well as the gear pumps used in IJP.
Linear flow adjustment is another major advantage of the new FP 400. The pump offers outstanding linearity between 10% and 100% of the nominal flow rate.
On top of that, the new pump maintains stable performance despite back pressure (up to 1 bar) and viscosity changes within the range of those found in typical industrial IJP inks. The FP 400 is therefore an excellent solution for applying glazes, enamels, hot melt inks, etc.
Last but not least, the FP 400 has been intensively tested for 18 months at major printer and ink manufacturers in Italy, Spain, Germany, the UK, and China and has already attracted a great deal of interest.