Front and rear shrouds have pump-out auxiliary vanes to reduce recirculation and seal contamination. Concave impeller vanes create double inward spiral flow at the vane tip, thereby avoiding serious recirculation and excessive wear at close impeller clearances.
This results in uniform wear, longer wear life of wet-end parts, improved shaft seal life and sustained high efficiency. Several types of hard metal and moulded elastomer impellers are interchangeable. Impeller threads are cast-in, eliminating the need for impeller inserts or nuts. The standard configuration is a closed, five-vane design, but other options are available by request.
Casing halves of cast or ductile iron with external reinforcing ribs contain the wear liners and provide high operating pressure. Where extraordinary high pressures are required, enquire about our HP series High Pressure Slurry Pumps.
Hard metal liners are interchangeable with pressure molded elastomers. The elastomer liners are bolted, not bonded, to the pump casing.
Elastomer seal rings back all liner joints. SPS Application Engineers are experienced to recommend the ideal liner material for your application.
Cartridge : Type Shaft and Bearing Assembly
The cartridge arrangement allows servicing in a clean environment without removing the pump. A large diameter shaft with short overhang minimizes deflection and vibration. Heavy-duty, grease-lubricated cylindrical and/or taper roller bearings are enclosed in a cartridge-type housing protected at both ends by a rotating labyrinth, double piston rings and grease purged lip-seal. Where drive power exceeds the maximum power rating of the standard bearing assembly, double-bearing cartridge assemblies provide greater power handling.
Interchangeable Shaft Sealing Arrangements
A reversible, slip-fit, stainless steel shaft sleeve, through hardened with O-rings at both ends completely protects the shaft. Tungsten coated shaft sleeves are offered for ultra-demanding applications. Hart pumps provide complete interchangeability of seal arrangements. Stuffing box in full flush or low flow configurations and centrifugal expeller are standard options. The expeller seal eliminates the cost, complexity and leak through of a stuffing box seal where suction conditions allow. In more than 80% of all applications this is the preferred seal type. Mechanical seals can be fitted to any size of pump.
A rigid, one-piece casting cradles the bearing assembly. Only four bolts are required to hold the bearing assembly in the frame. An easy means of external impeller adjustment is provided in a convenient position below the bearing housing.