Design And Operational Requirements
- Non-Vertical Operation: Vertical Shaft-up (0°)
to Horizontal (90°) operation is acceptable as long
as the pump transmits down-thrust to the motor
within 3 seconds after start-up and continuously during
operation. However, it is best practice to provide a positive
slope whenever it is possible, even if it is only a few
degrees.
- Motor, Sleeve, and Pump Support System: The booster
sleeve I.D. must be sized according to the motor cooling
and pump NPSHR requirements. The support system must support
the motors weight, prevent motor rotation and keep
the motor and pump aligned. The support system must also
allow for thermal axial expansion of the motor without creating
binding forces.
- Motor Support Points: A minimum of two support
points are required on the motor. One in the motor/pump
flange connection area and one in the bottom end of the
motor area. The motor castings, not the shell area, are
recommended as support points. If the support is a full
length support and/or has bands in the shell area,they must
not restrict heat transfer or deform the shell.
- Motor Support Material and Design: The support system shall not create any areas of cavitation or other areas of reduced flow less than the minimum rate required by this manual. They should also be designed to minimize turbulence and vibration and provide stable alignment. The support materials and locations must not inhibit the
heat transfer away from the motor.
- Motor and Pump Alignment: The maximum allowable
misalignment between the motor, pump, and pump discharge
is 0.025 inch per 12 inches of length (2mm per 1000mm of
length). This must be measured in both directions along
the assembly using the motor/pump flange connection as the
starting point. The booster sleeve and support system must
be rigid enough to maintain this alignment during assembly,
shipping, operation and maintenance.
- The best motor lubrication and heat resistance is obtained with the factory based propylene glycol fill solution. Only when an application MUST HAVE deionized (DI) water should the factory fill solution be replaced. When a deionized water fill is required, the motor must be derated as indicated on the below chart.
The exchange of the motor fill solution to DI water must be done by an approved Franklin service shop or representative using a vacuum fill system per Franklin's Motor Service Manual instruction. The motor shell then must be permanently stamped with a D closely behind the Serial Number.
The maximum pressure that can be applied to the motor internal components during the removal of the factory fill solution is 7 psi (0.5 bar.)
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First: |
Determine maximum
Feed Water Temperature that will be experienced in this application. If the feed water excedeeds the maximum ambient of the motor, both the DI water de rating and a hot water application derating must be applied. |
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Second: |
Determine the
Pump Load Multiplier from the appropriate Service Factor curve.
(Typical 1.15 Service Factor is for 60Hz ratings &1.00 Service
Factor for 50Hz ratings). |
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Third: |
Multiply the
Pump Load Requirement times the pump load multiplier number indicated on the vertical axis to determine
the Minimum Motor Nameplate Rating. |
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Fourth: |
Select a motor with a nameplate equal or higher
than the above calculated value. |
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- Motor Alterations - Sand Slinger & Check Valve
Plug: On 6" and 8 motors, the rubber sand
slinger located on the shaft must be removed. The pipe plug
covering the check valve must be removed from Ni-resist
and 316 SS motors. The special Booster motor already has these alterations made.
- Frequency of Starts: Fewer than 10 starts per 24-hour
period are recommended. Allow at least 20 minutes between
shutdown and start-up of the motor.
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