Grundfos Submersible Pump Flow Sleeve
Grundfos offers a complete range of stainless-steel flow sleeves for both vertical and horizontal operation. Flow sleeves are recommended for all applications in which motor cooling is insufficient. The result is a general extension of motor life. Flow sleeves are to be fitted in the following cases:

• If the submersible pump is exposed to high thermal load, such as current unbalance, dry running, overload, high ambient temperature and bad cooling conditions.
• If aggressive liquids are pumped, since corrosion is doubled for every 10 °C the temperature rises.
• If sedimentation or deposits occur around and/or on the motor.
• If there is a top feeding in the well to ensure the flow velocity past the motor.

Maximum Liquid Temperature
The maximum permissible liquid temperature depends on the flow velocity of the liquid past the motor. See the table below.

Grundfos motor	Flow velocity pass motor (m/s)	Maximum liquid temperature (C)
MS4"	0.15	40
MS4" T60	0.15	60
MS6000	0.15	40
MS6000 T60	1.00	60
MS6000P	0.15	60
MMS6" with PVC windings	0.15	25
MMS6" with PVC windings	0.50	30
MMS6" with PE/PA windings	0.15	45
MMS6" with PE/PA windings	0.50	50
MMS 8", 10", 12" rewindable with PVC windings	0.15	25
MMS 8", 10", 12" rewindable with PVC windings	0.50	30
MMS 8", 10", 12" rewindable with PE/PA windings	0.15	40
MMS 8", 10", 12" rewindable with PE/PA windings	0.50	45

Note: For MMS 6", 37 kW, MMS 8", 110 kW, and MMS 10", 170 kW, the maximum liquid temperature is 5 °C lower than the values stated in the table above. For MMS 10", 190 kW, the temperature is 10 °C lower.

Example of calculated flow sleeve The flow sleeve is fitted to the submersible motor so that the liquid passes close by the motor on its way towards the pump suction interconnector. This ensures the optimum cooling of the motor.


Submersible motor diameter
MS402 = 95mm
MS4000 = 95mm
MS6000 = 139.5mm
MS6000P = 139.5mm
MMS6 = 144mm
MMS8000 = 192mm
MMS10000 = 237mm
MMS12000 = 286mm

Oversize motor
Flow sleeves for pumps with oversized motor and for pumps with non-standard motor are available on request.