When performing some critical sample measurements on the seabed, it is important that collected samples are thoroughly mixed to ensure a constant concentration throughout the solution. To ensure that subsea samples can be mixed efficiently in situ, KUMO developed the Stirrer.

The Stirrer is comprised of a mini-motor with a gear, all contained within a compact pressure-proof tube. The tube is supplied with external power via a pressure-proof subsea connector sealed using an O-ring. The Stirrer can be deployed to operational depths of up to 6,000 m.

The design of the Stirrer is very simple: once power is provided it will begin rotating with speed increasing linearly with voltage. The Stirrer slowly but steadily maintains equal concentration within the probe with the best results achieved in the absence of a concentration gradient.

The Stirrer comes fitted with magnetic coupling to ensure there are no consistency problems at the shaft, no friction forces to be overcome; and low power consumption during operations.


  • In-situ sample mixing instrument for deep sea operations

Features / Benefits:

  • Low power consumption
  • Withstands extreme external pressure
  • Compact design
Revolution  50 – 200 U/min 
Power  10 – 25 mA
Pressure  600 bar 
Voltage  1.5V – 6V
Material – Titanium or stainless steel– POM
Operational depth 6000 m
Operational temperature range -5 to +60 °C
Dimension (without sticks) Diameter – 25 mm, Length – 130 mm 
Weight  0.310 kg