Submersible motors

Range 4F

4” Water filled canned submersible motors

4” high-yield, water lled canned submersible motors, totally made of stainless steel AISI 304 (for the parts in contact with the water). The use of high-quality materials highlights the electrical and mechanical properties of the motors.


The stator, 24-slot lamination made, hermetically sealed and resin filled by means of a vacuum process.
This procedure guarantees:
• great mechanical strength, in case the motor is dipped in deep wells;
• maximum electrical isolation;
• excellent heat exchange;
• the motor to work perfectly with inverter “Inverter Resistant”.
The rotor shaft, carbon-steel alloy in the rotor area. The protrusion is in stainless steel AISI 304 up to 3 hp; from 4 hp to 10 hp it is in stainless steel DUPLEX that guarantees an excellent mechanical resistance, which is absolutely necessary with very high starting torque.
The thrust bearing system, Kingsbury type, provided with stainless steel thrust bearings pads on a self-aligning system. The lapping process guarantees great reliability and ef ciency.
The cable (approved KTW, ACS, WRAS) is equipped with a special connection plug that allows an easier substitution of the cable in case a longer one is needed.
The filler liquid, clear water with addition of propylene glycol. The most important function is to lubricate the bushings and the thrust bearing, besides it’s very important to avoid the freezing if the motor is stored in cold sites.
The liquid replenishment valve allows water to get in to replenish the internal equilibrium, what’s more it guarantees a constant lubrication of the upper bushings and the compensation membrane can work properly.


  • Flange 4'' NEMA
  • Insulation class: F
  • Protection type: IP68
  • Ambient temperature: max 35 °C
  • Voltage tolerance: +6% / -10%
  • Installation under the water level: 350 m
  • Cooling rate: min. 0,15 m/s


  • Tensions / various frequencies

Documentation available


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Operating and Maintenance Manual

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Montorso Vicentino (VI) - Italy
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