Tag Archive: Prerotation System

What are Prerostal Systems and How do They work?

Posted on by Sara Springer

The Prerostal and PreroClean Prerotation Systems Simplify Waste Water Processes

Hidrostal Prerostal Pumps in ServicePrerostal® Pre-Rotation System:

The PREROSTAL® Prerotation system is a unique, economical, uncomplicated method of automatically adjusting pumping volume to match varying inflow rates using a constant speed motor and pump. It combines the screw centrifugal impeller of a Hidrostal pump with a special chamber around the suction pipe. The chamber utilizes gravity to impart a fluid spin in the same direction of rotation as the pump impeller. As a result, this spin produces a flow reduction without the necessity of changing pump speed. Furthermore, this method of matching pump outflow to pump station inflow eliminates the need for any electrical equipment such as inverter drives.

In addition, the PREROSTAL system is a highly effective sump cleaning system which does not require any additional mechanical or electrical components such as controls for mixers or aerators.  It is the ideal solution for handling variable flow applications with large or troublesome solids.

PREROCLEAN™ Pre-Rotation System:

The PreroClean™ Self Cleaning Sump is a simplified version of the PREROSTAL. In applications where the primary aim is maintaining clean sumps without the need for flow matching, Preroclean is the best choice. This option works the same as the PREROSTAL but the weir height and channel dimensions are fixed for each pump size. Due to this, construction can be simplified by moulding the system as a single piece.

The PREROSTAL system is a proven and cost effective replacement for Archimedean screw pump systems.  We have successfully replaced numerous installations around the world!

Prerostal Advantages over Archimedean Screw Systems:

  • Require less space
  • Fluids are More Contained: Less smell and exposure risk
  • Require less ancillary equipment


The below video is an in depth look at the system features and benefits, especially as compared to archimedean screw systems.

What is a Prerostal System and how does it work?