- International standards organization. Sets pump and seal
standards for the metric community.
- Attaches to the end of the shaft to impart energy to the fluid
being pumped. Available in open, semi- open and closed
- The center of the impeller or the point where fluid enters the
- Open impellers require a clearance between the volute or the
pump back plate depending upon design. This clearance must be set
when the pump is at operating temperature and must be reset to
compensate for wear. (0.015" to 0.020" or 0,04 mm to 0,05 mm is
- the plates located on one or both sides of the impeller vanes.
Prevents solids from penetrating behind the vanes.
- Located between the eye and the discharge side of the
impeller. Directs the flow of the liquid to the outside diameter
of the impeller.
- The opposite of explode. Bubbles implode in the higher
pressure areas of the pump making noise and causing damage to the
metal parts. This is normally called cavitation
- A non metallic slug of material which has become entangled in
the metal during its manufacture. A severe problem in thin cross
section metal bellows manufacture.
- A small axial flow vane that attaches to the impeller of a
centrifugal pump to increase the N.P.S.H. available.
- The most common type used in industry. Has a slippage of 2 to
5 percent compared to synchronous motors.
- Mounted in the piping. No base plate or alignment
- A loss of efficiency caused by liquid flowing through wear
rings or the impeller to volute clearances.
- A corrosion of the grain boundaries in the body of the
- A technique used in impeller design. You repeat the action
until you get to the final result. Very difficult to do until the
new computer programs became available.
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CD, with over 600 Seal & Pump Subjects
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