UnderWater Motors –  

Stator-Pressure-Type Submersible Motors 2250 metres

Product Overview

The WHEATSTONE UnderWater Motors is designed :The core concept behind the stator-pressure-bearing submersible motor is “using flexibility to overcome rigidity.” Through ingenious structural design, it balances the internal pressure of the motor with the high external pressure of the deep sea, thereby preventing the housing from being subjected to a massive pressure differential.

Key Features

• Extreme Pressure Resistance (Suitable for All Ocean Depths):

  The stator core and windings themselves are designed to withstand pressure, so the motor does not require a heavy pressure-resistant housing. The interior is typically filled with oil and pressurized to match the external pressure; therefore, whether the water depth is 1,000 meters or 11,000 meters, the force acting on the housing remains constant, making it theoretically suitable for all ocean depths.

• High power density: 

       By eliminating the heavy, high-voltage-rated housing, the proportion of effective motor material is significantly 

       increased. For the same weight or volume, the output power is far higher than that of traditional sealed motors; 

       for the same power output, volume and weight can be reduced by 30%–50%.

• Excellent heat dissipation:

   Internal insulating oil or external seawater can come into direct contact with the stator to carry away heat, resulting in a short heat transfer path. Compared to sealed motors that rely on “air + a thick housing,” heat dissipation efficiency is significantly improved, allowing for higher current densities.

• High Reliability: 

     The elimination of dynamic seals at the rotating shaft removes the primary failure mode caused by seal wear  leading to water leakage (low risk of motor body failure), resulting in a long service life and extended  maintenance-free intervals.

Technical Highlights

• Motor Type: Oil-Filled DC Servo Motor

• Maximum Submersion Depth: 2250 meters

• Protection Level: IP68+ / Pressure-compensated

• Housing Options: Stainless steel / Titanium alloy

• Cooling Method: Oil-filled cavity with natural convection / optional liquid-cooled system

• Customization: Torque, speed, and gearbox integration available

Motor Dimensions

Electrical Parameters