Abstract: A scanning gauge and scanning method are disclosed for measuring the effective open area of a throat formed between adjacent vanes secured together at their ends by buttresses or the like wherein locators are mounted on an elongated guide assembly for engaging the vanes forming the throat, a scan element is arranged for traversing the elongated guide assembly in longitudinal movement along the radial length of the throat for assessing radial length thereof, a sensor head is supported by a floating mount on the scan element to remain in engagement with the trailing edge of one vane and a convex surface of the adjacent vane during sweeping movement of the scan element about an axis generally parallel to the trailing edge of the one van for assessing the shortest opening dimension at various sections along the length of the throat, longitudinal and sweeping movement of the scan element being effected by a longitudinal stepper motor and a sweep motor each including mechanical limit switches for monitoring and reg

Abstract: A classification instrument adapted for accurately measuring both blocked and open flow area for airfoil or vane elements such as turbine stator vanes having mounting buttresses at each end includes stops for mounting the vane element upon the instrument in a predetermined position established by a plurality of datum points or lines corresponding to the various stops, a plurality of indicators for measuring various points and surfaces upon the vane and providing classification readings from which the open and closed area values for the vane may be determined. A method is also disclosed for classifying or determining the blocked and open areas for such air foil or vane elements.

Abstract: A classification gauge and method of operation for accurately and repeatably measuring the open flow area of a pair of air foil or vane elements interconnected by end buttresses, the classification gauge including first and second sets of probes arranged for contact with the vanes adjacent the open flow area and first and second lateral probes for engaging the end buttresses, an indicator of open flow area being effectively interconnected with the two sets of probes and the two lateral probes by means of a proportional mechanism.