Moment Weighing Scales for Jet-engine Blades
Series WM

Range of application
Determining the radial, axial and tangential moments of jet-engine blades for evaluation of mass and position of center of gravity.

Application of the scale in testing, inspection and quality control.

With the use of the optional BLADIS Net blade-distribution system, the exact position of the blade in the assembly can be determined.

Design
Electronic scale on a base plate with built-in levelling device.

Weigh-beam mounted on knife-edges for friction-free operation, including oil damping, measuring system with load-cell and microprocessor-controlled measuring unit (digital display), thus, ensuring high weighing accuracy and repeatability. An adapter flange is provided for mounting the blade adapter.

Single-axis or dual-axis types according to the application and blade form.

With multi-axis equipment, the axial and tangential moments can also be measured. This is especially necessary for wide chord, heavy blades. With the single-axis scale only the radial moment is determined.

The central element of the Schenck RoTec moment weighing scale is a solid, horizontal beam mounted friction-free on knife-edges. With a blade mounted on the adapter flange, the moment is determined by a precision load-cell and the lever-arm. In the case of single-axial scales, the important radial moment is determined. A digital measurement and display instrument ensures a broad measurement range along with high display sensitivity.

If the mass distribution of the blades is known, the blades can be installed on the turbine disc in a sequence that will result in the lowest possible residual unbalance. This may become a difficult task, even in standard applications, and in particular when the unbalance of the disc is to be compensated for by the blade positions. Complex tasks of mass and radial moment processing are completed quickly, efficiently and cost-effectively by the blade optimization program BLADIS Net. This runs on an IBM-compatible PC directly connected to the moment weighing scale. For multi-axis evaluations BLADIS 3D is available.