Franklin Electric submersible motors are designed to operate with a cooling flow of water over and around the full length of the motor.

If the pump installation does not provide the minimum flow shown in Table 6, a flow inducer sleeve (flow sleeve) must be used. The conditions requiring a flow sleeve are:

• Well diameter is too large to meet Table 6 flow requirements.
• Pump is in an open body of water.
• Pump is in a rock well or below the well casing.
• The well is "top-feeding" (a.k.a. cascading).
• Pump is set in or below screens or perforations.

Franklin Electric’s standard submersible motors, except Hi-Temp designs (see note below), are designed to operate up to maximum service factor horsepower in water up to 86 °F (30 °C). A flow of 0.25 ft/s for 4” motors rated 3 hp and higher, and 0.5 ft/s for 6 and 8 inch motors is required for proper cooling. Table 6 shows minimum flow rates, in gpm, for various well diameters and motor sizes.

If a standard motor is operated in water over 86 °F (30 °C), water flow past the motor must be increased to maintain safe motor operating temperatures. See HOT WATER APPLICATIONS on page 7.

Note: Franklin Electric offers a line of Hi-Temp motors designed to operate in water at higher temperatures or lower flow conditions. Consult factory for details.

If the flow rate is less than specifi ed, then a fl ow inducer sleeve must be used. A flow sleeve is always required in an open body of water. FIG. 1 shows a typical flow inducer sleeve construction.

EXAMPLE : A six-inch motor and pump that delivers 60 gpm will be installed in a 10” well.

From Table 6, 90 gpm would be required to maintain proper cooling. In this case adding an 8” or smaller flow sleeve provides the required cooling.