Manual Eddy Current Probe

This manual eddy current probe was designed and fabricated for Siemens Power Corp. to enable in situ examination of 80+ percent of the concave surface and ~35 percent of the convex surface of steam power turbine blades. The only access to these blades is through a .47 inch diameter view port. It was necessary to design the probe to go through that small port and then be able to be articulated over as much of the blade surfaces as possible. Again, we must apologize for the quality of the photos. This was a panic job so some quick snapshots were all that were possible. These snap shots were taken prior to the eddy current coil installation by United Western Technologies of Pasco, WA.

Construction materials were square brass tube, wrought brass stock, Delrin™, 304 stainless steel, Torlon™, and graphite filled nylon.

The photo below shows the probe partially disassembled with a 5 inch pocket comb for size comparison (Yes, a scale would have been a better choice, I know. When I said time for a few snapshots I meant it). To retract the probe back through the view port, the arm must be straightened and the foot held parallel to the arm. These functions are provided by the components seen to the left.