Recessed Impeller Pumps

• The impeller develops a vortex within the casing that is entirely out of the flow path of the impeller, creating a fluid stream within the open casing with nothing to impede the flow.
• The impeller vortex of fluid mass extends towards the suction. The vortex produced draws the particles/solids into the fluid stream.
• These particles/solids swirl into the fast moving vortex within the pump casing.
• The majority of solids/particles are discharged in less than one revolution due to centrifugal force induced by the vortex action, the liquid stream being the main propulsive force. The majority of solid material seldom touches the impeller itself.

Historically, one of the primary issues with recessed impeller pumps was the fact that the cupped impeller design produced very high axial thrust loads. To overcome this, manufacturers simply added additional thrust bearings to withstand the high thrust loads rather than overcoming the root of the problem. PATS’ recessed impeller pumps have a unique impeller design that has completely eliminated the issue of axial thrust loads, whilst maximizing hydraulic efficiency. The impellers provide exceptional gas handling properties and offer extremely long service life essential for a trouble free, low maintenance installation.

Superior abrasion resistance is maintained by the unique casing and impeller design which imparts the vortex action causing very little solid content to come into contact with the impeller, minimising abrasive wear and maintaining solids integrity.