Netzsch introduces screw pumps for a wide variety of media

Netzsch Pumpen & Systeme has expanded its range of progressing cavity pumps and rotary lobe pumps with a three-model series of compact screw pumps, the Notos two-, three-, and four-spindle models.

Depending on the type, they are suitable for non-lubricating substances at high pressures up to 80 bar and temperatures up to 300°C.

They thereby cover a wide range of application areas from lubricants to sealants and on to bitumens or resins.

The core feature of the screw pumps from Netzsch is their concept following the high efficiency unique design (HEUD) and producing a proven improved force/performance ratio.

This is due, on the one hand, to the hard materials used – the choice ranges from simple grey cast iron to chrome-nickel steel and on to duplex or Hastelloy alloys – depending on the requirement.

The stability of these materials ensures very minor sagging of the spindles, even under the high loads typical for screw pumps.

This allows working with very narrow tolerances between dynamic and static parts in the manufacturing process.

Possible back-flow from the higher pressure to the lower pressure side is thus reduced and the delivery efficiency increased at the same time.

The shape of the spindles has also been adapted to minimise interferences and resistances in the material flow.

Due to the design of the spindles, medium transport largely free from turbulence and pulsation can be achieved.

The special design also prevents foam development and hardly generates running noise.

Each pump is designed specifically for the respective application area, especially in terms of size, which concerns rotational speed and the sliding velocity of the parts moving in synch.

A duct connects the high-pressure side with the space of the intake side, and thus the prevailing forces negate each other and the net axial force is nearly zero.