Pump Type Follows:

Wednesday, June 3, 2009

Sealless Pumps

Completely leakproff pumps are available for pumping corrosive, volatile, radioactive and otherwise hazardous liquids. Canned motor pumps are an assembly of a standard centrifugal pump and a squired cage induction motor in a hermetically sealed unit. Modifying a recalculating flow system in a canned motor pumped can allow it to be used in applications at up to 1000 oF (638 oC).

Magnetic drive pumps are an assembly of a rotor, an impeller, product lubricated bearings and a magnetic carrier inside an isolation shell or diaphragm. This rotor is driven by magnets outside outside the shell or diaphragm. No mechanical connection exist between the driven magnet and driving magnets. No seal exist and thus we have the term “sealless.”

Straight Radial Vane High Speed Pumps

For handling volatile liquids at low flow rates and high heads, the straight radial vane impeller in a diffuser casing offer several advantages. Volatile low specific gravity, poor lubricity liquids require larger running clearances, which is not possible with conventional high head multistage centrifugal or positive displacement pumps. High head pumping of this liquids can be handled by operating this completely open impeller at very high speeds through an integral gear increaser and with very large impeller to casing clearance, typically 0.030 to 0.070 in (0.76 to 1.8 mm). Test of one manufacturer’s design have shown this clearance can increase t 0/125 in (3.2 mm) with virtually no change in performance, and consequently there is no need to provide adjustment for impeller axial clearance.

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