Silent Pumps

• Noise reduction by an average of -10 dBA
• Operating frequency ranges adapted for optimized working conditions for the user
• The 22-tooth helical profile on series 0 pumps, unique for that size of pumps
• Capacities available are 1,00 – 1,25 – 1,50 – 1,70 – 2,00 cc/rev for operating pressures from 125 to 250 bar

Noise reduction is indeed becoming the real challenge for today’s industrial market. Market competitiveness and new European regulations in the material handling sector, particularly for pallet trucks, are such that suppliers are compelled to develop new technologies and meet enhanced customer requirements. Acoustic nuisances have several origins: pump hydraulic pulsations, being propagated through hoses and pipes which then affects the truck frame structure (structure-borne sound) and aerial noise (rotation frequency of an electric motor or a pump) which can be contained by an acoustic cover.

Very compact, our Silent Pump technologies result in amazing noise pollution reductions.

Comparison of 1,00 cc/rev and 1,25cc/rev capacities using standard and silent pinion technology. The tests were realized in HPI’s own anechoic room on a power pack with a 1,2kW motor.

We worked closely with our Blois (France) production site R&D Department, dedicated to automotive applications, to develop a unique side plate profile, which is the component that contributes to noise reduction. We took advantage of our technology developed over several years for steering systems and adapted it to our material handling sector applications. We applied our technology, thanks to new tests and research development, and enhanced it in order to cover a wider range of capacities and pressures in accordance with our customer requirements.

In order to minimize hydraulic pulsations, we designed a specific helical tooth profile with a suitable propeller angle and increased the number of teeth of the pinions from 12 to 22.

Acoustic results show that the noise level has been reduced by an average of -10 dBA, when compared with a standard external gear pump. The new HPI Silent Pump is also characterized by a much more pleasant sound when in use. Indeed, the operating frequency ranges have been adapted for user optimized working conditions. The 22-tooth helical profile on series 0 pumps, unique for that size of pumps, significantly reduces hydraulic pulsations. The capacities available are 1,00 – 1,25 – 1,50 – 1,70 – 2,00 cc/rev for operating pressures from 125 to 250 bar.

All our Silent Pumps are available on our micro power packs 2G and will soon be available on our 3G and 4G power packs.