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Special Pumps

Figure 9.8: Service water pump (Reproduced Figure 9.9: Vertical can pump (Reproduced
with permission of Goulds Pumps, ITT with permission of Goulds Pumps, ITT
Industries) Industries)

Most of these pumps have motor drivers with thrust bearings in the
motor. A hollow shaft motor is frequently used, and this allows the
pump lineshaft to pass through the motor and be secured by the thrust
beating at the top. Others use a solid shaft motor with the coupling
located in the discharge head assembly above the stuffing box.
The Vertical Can pump shown in Figure 9.9 incorporates the Column
and Bowl Assembly within a pressure containing suction vessel that is
constructed in accordance with ASME Section VIII. These pumps are
widely used in the Petrochemical industry as pipeline or booster pumps
where the NPSH available is very low. This design increases the NPSH
available by lowering the first stage impeller into a longer suction can,

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