ROLLS ROYCE – AZIPULL TORQUE TEST RIG, LOCATED IN NORWAY
An Azipull is a low drag, high efficiency pulling thruster that provides steering and propulsion at powers upto 5000 Kw, these are typically installed on offshore vessels for manouvering into the drilling positions.
Comar designed a test rig as a turnkey project , providing the fabrication , input drive via a variable output hydraulic motor and an output loading system , both in closed loop control of torque and speed . The test stand had to cater for a variety of units of different sizes and torques with driveline speeds of 1-2rpm 0-70 kNm input torque and output torques of 0-200 kNm.
A variable delivery Linde axial piston pump was used to supply the flow to a Linde axial piston motor coupled to a 173:1 planetary gearbox for the input drive . The output braking torque was provided by a Rexroth (Hagglunds) CB840S radial piston motor . Input torque , output torque , pressures , flows and temperatures were all monitored and data logged to give results of each test .
To simulate the thrusts experienced on the Azipull gear train and bearings , the output transmission shaft had to be subjected to thrusts of 400 kN.
The noise from the test rig was not to exceed 85 dBA and health & safety was an important factor in the manoeuvring and location of the Azipull unit as the largest unit weighed approximately 17,600kgs.
