Page 197 - Know and Understand Centrifugal Pumps
P. 197
M ech a n i ca I
Seals
Pump packing
Many industrial pumps around the world still use ring packing as the
shaft seal. These packings require continual maintenance. They need to
be tightened and adjusted and it is necessary to change them frequently.
Packings wear and damage the shaft or sleeve of the pump, which
necessitates their frequent replacement. The leakage fiom the packing
gland corrodes the pump, base plate and foundation. The drips can
enter into the bearings and contaminate the bearing lubricant. This
sacrifices the life of the bearings.
The majority of existing pumps that were originally designed for
packings can be converted to use mechanical seals. Consider the
following. We have many pumps in our private everyday lives.
Practically all are adapted to mechanical seals. The family car has about
6 pumps with mechanical seals:
The radiator water pump.
The fuel pump.
The oil pump.
The power steering pump.
The pump that sprays and cleans the windshield.
The air conditioning compressor.
Do you have two cars? Then you have about 12 pumps with seals. And
in your house, how many sealed pumps do you have? In the kitchen,
mechanical seals are on the pump in the dishwasher, the blender, the
refrigerator compressor, and the garbage disposal under the sink. Do
you have a clothes washer? There are two seals on the clothes washer,
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