Shaft power meter, Torque and power measurement system for rotating shafts
The KONGSBERG Shaft Power Meter, called MetaPower® system allows the ship's management to maintain or increase the speed while saving significant amounts of fuel, reducing CO2 and NOx output levels. It measures torque and power transferred from the main engines to the propellers. Comparison between power output and fuel consumption gives valuable information avoiding over-stressing of the engine.
The MetaPower® system measures the RPM (revolutions per minute), torque and power transferred from a ships main engine to the propeller(s)
MetaPower® shaft power meter is a digital measuring system using a laser beam for detection of shaft torque, shaft RPM and consequently the transferred power. The system offers high accuracy and good long term stability.
By transmitting measured data via satellite from ship to shore, the shipping company's operation management is able to decide the most economical operating modes for the ship's engine and propulsion system.
MetaPower® can be delivered as a stand alone installation or integrated to KONGSBERG K-Chief automation system or AutoChief 600 propulsion control system.
The main benefits of the MetaPower® system are:
- Continuous, highly accurate measurements
- Reliable and maintenance-free operation
- Robust construction
- The sensing elements can be installed in hazardous areas
- Suitable for any shaft diameter
- Easy-to-read displays and graphics
- Integration into control and monitoring systems and data networks
- Excellent price/performance ratio
- For shafts rotating at up to 30.000 RPM
The system is 100% digital, based on measuring with an infrared laser beam guided through fiber optics.
The MetaPower® System measures the twist of a rotating shaft. Two slotted wheels are mounted on the shaft. Light is transmitted by LEDs through the slots in each wheel, converted to a digital electronic signal and sent back to the processing unit for calculation of the corresponding torque. The system displays RPM, torque and power.
The following can be measured and read out:
- Shaft RPM
- Torsional angle between two cuts of the shaft, i.e., the torque
- Power transferred by the shaft
The measured figures are displayed on analogue instruments, in digital form on an LCD (Liquid Crystal Display) monitor or both analogue and digital on a standard PC monitor.
MetaPower used on ships
In July 1999, full scale tests of MetaPower were commenced on board Fjord Line's M/V "Bergen", a passenger and car ferry sailing in a shuttle between Bergen and Hanstholm in Denmark. In October 1999, full scale tests were also initiated on board Solstad Shipping AS' offshore vessel "Normand Progress."
The test programs covered continuous logging and read-out of the propeller shafts' RPM, torque, power and the total energy transferred to the propellers. These logged figures were in turn be compared to the total consumption of fuel in order to optimize the operation of the ship. Both test programs were completed with excellent results.
MetaPower has been installed on board a range of different ship types including passenger vessels, tankers, offshore vessels, cargo/container ships and seismic survey vessels. Ships with both one and two shafts/propellers.
MetaPower is used for many different purposes including optimizing of ship performance, fuel reduction, NOx reduction and to save maintenance costs by minimizing down time. By using MetaPower's additional torsional oscillation analysis, ship owners are able to monitor their propeller shafts and thrusters over periods of time for preventive maintenance and corrective actions.
The MetaPower shaft power meter system is classified by the International Patent Cooperation Treaty to be a novelty, an inventive step and to have industrial applicability. The Intellectual Property Rights to the MetaPower system were granted by patents registered in the most important industry and shipping countries, including USA.