Raptor Scientific builds the most accurate scales for the measurement of blade moment weight as well as the most repeatable adapters. Moment Weight Scales Basic Machine Operating Concept A turbine blade is mounted on one end of a balance beam and a counterweight which offsets the moment of the holding fixture ("adapter") is mounted on the other side. The blade is then inserted in the adapter. A force transducer determines the moment. Most manufacturers use a knife edge and load cell to measure moment. This results in poor accuracy and reliability. Machines manufactured by Raptor Scientific use crossed-web flexure pivots and force restoration technology, resulting in an instrument which is at least 10 times more accurate than other methods and is also more resistant to damage in a production environment. In our scale, a laser detects a shift due to blade moment and a feedback circuit applies an electromagnetic force to counteract the deflection. The current applied is converted to a measurement of force. Our pivot consists of strips of spring steel which are oriented to create a single center of rotation.
We do not use knife edges, because they are not capable of the 0.000,050 inch pivot accuracy required. Raptor Scientific MW Series of Moment Weight Scales use unique technology resulting in accuracy 10 times better than traditional methods.