FELUWA MULTISAFE® double hose-diaphragm pumps
for abrasive, aggressive and toxic media

DownFlow Technology (DFT)


Traditional diaphragm pumps

Pumping of heterogeneous mixtures and fluids containing coarse contaminations calls for custom-tailored solutions to ensure permanent trouble-free operation.

With traditional diaphragm pumps there is the risk of excessive stretching of the diaphragm in the pump head or suction valve so that it may even be pressed into the discharge check valve, which inevitably results in diaphragm failure. Such a case of breakdown cannot be avoided by the use of double flat diaphragms, because both diaphragms are subject to almost identical stress and will therefore rupture concurrently.

Our Solution: Flow from the top to the bottom

In order to avoid disadvantageous sedimentation, MULTISAFE® double hose-diaphragm pumps literally turn the traditional pumping principle upside down, which means flow from the top to the bottom. The cylindrical shape of the diaphragm with maximum linear flow lines panders to the flow behaviour and avoids the settling of solids. Handling of fluids carrying large solids moreover requires special and custom-tailored check valves.

The downflow configuration is therefore specially designed for the handling of particularly heavy solids and herterogeneos mixtures.

Valve options

Handling of fluids carrying large solids requires special and custom-tailored check valves.

Various design options, which assist the passage of coarse solids carried by the fluid, are available for downflow configuration, such as spring-loaded ball valves, spherical cap ball valves or special floating ball valves. In case of critical process conditions, in which the continuous flow must by no means be interrupted, double valves in cassette design avoid backflow leaks resulting from jammed solids.

Downflow floating ball valve - closed
Downflow floating ball valve - open
Spring-loaded downflow cone valve
Downflow ball valve