Progressive Cavity Pumps

This pump principle works something like a corkscrew where a helical shaped rotor rotates within a double helix elastomeric stator.   The rotor seals tight against the stator helix lip as it rotates forming a string of cavities in between where the fluid is moved in a continuous motion and relatively free from pulsation. This allows for moving abrasive slurries at low volumes to medium & high heads. Also due to its ‘gentle’ type action, adapts well to moving delicate media such as soups & yoghurts and thixotropic materials where shearing is to be avoided.

Stevco Cavity Pump Gif

Advantages

Self Priming

 

Low Pulsation

 

Can pass solids

 

Can process air with the liquid

 

Few moving parts

 

Low flow rates at Pressures to 24bar

 

Good for dosing viscous additives

 

Lower speeds for abrasive liquids

 

Low service requirement

 

Readily available spare parts

Limitations

Limited flow rates

 

Will not tolerate operator misuse

 

Expensive to repair

 

Expensive for materials other than standard irons

 

Limited fluid temperatures with special modifications required


Significantly larger than comparable options of similar duty

 

Life dependant on operating speed.

 

 

 

 

Common brands serviced include;

 

Mono, Southern Cross, Netzsch, Allweiler PCM, Seepex, Sulzer, Flowrox, Roper, Monoflo, Moyno, Inoxpa, Wangen, Roto, Bornemann and SPX.