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A.0100.301 – IM-FIP/08.00 EN (02/2014)
2.4 Shaft seals
2.4.1 Mechanical seals
Recommended for foodstuffs, solvents and
heavier chemicals. Only FDA mechanical seals
are approved for food applications. Delivered
as standard with seal surfaces in carbon vs
ceramic.
The mechanical seal for hygienic stainless
steel pumps are supplied with an extra O-ring
to seal off the area behind the stationary seal
part. This will allow easy cleaning with seal in
place, and eliminate liquid to remain behind the
seal. Only FDA O-rings are approved for food
applications.
2.4.2 Lip seals
Recommended for sticky and viscous liquids as
lip seals do not require as much lubrication as
mechanical seals.
2.5 Impellers
The impeller is a wearing part and the
performance of the pump will change with the
wear. Flow and pressure will be reduced with
the length of the duty.
Abrasive liquids will shorten the service life of
the impeller, and low speed is recommended.
With low speed, a constant flow will be
achieved during a longer period of time.
Following factors will effect the service life:
• Temperature, see next page
• The working pressure of the pump
• The speed of the pump
• Impeller material properties
• Lubrication properties of the liquid being
pumped
Splines
Double flat
