Torsional Vibration Analysis on Tanker Propeller Shaft
Hagen Andersen, DNV (USA) Inc., uses the TorqueTrak 10K telemetry instrument from Binsfeld Engineering to perform true mechanical Torque & Power measurements on marine propeller shafts. Shown below is a recent case study.
DNV was contracted by a United States ship owner to perform torsional vibration measurements on the main propulsion system, specifically on the propeller shaft of an oil tanker. The ship owner's concern was related to the torsional vibration damper on the main engine. They needed to know if the damper was functioning properly. DNV was tasked with getting torsional vibration measurements from the intermediate shaft which would show the effectiveness of the damper.
They did so by using the TorqueTrak 10K in conjunction with a Vishay strain gage and DNV's Nauticus Torsional Vibration Software. This combination allowed DNV to accurately measure the torsional vibrations within the ship's propulsion system and compare the measurements with the predicted values from the analysis carried out using the Nauticus Torsional Vibration Software. Using this combination DNV determined that the torsional vibration levels were acceptable and the damper was operating satisfactorily.
Vessel data: Type of vessel : Multi Product Carrier DWT : 42,000 Main engine MCR power: : 12,500 kW Main engine MCR speed: : 90 RPM Propeller type: : 4 Bladed Fixed Pitch Propeller diameter: : 7,400 mm