SwRI Turbine Disk-Rim Ultrasonic Inspection System

The Turbine Disk Rim Ultrasonic Inspection system is shown in preparation for an inspection at a Japanese Utility plant. The scanner is in place and the probe holder is being used to examine evidence of stress corrosion cracking in the blade attachment region of the turbine disk rims. In the background an operator is preparing the acquisition system for inspection. The developers, Dennis Hamlin and Jim Crane (principal investigator), are shown in the bottom left inset.

The purpose of this nondestructive inspection system is to perform reliable ultrasonic (UT) examinations of the blade attachment region of turbine disks without necessitating time consuming blade removal.

Use of this system greatly reduces the cost of inspecting all blade attachments to detect stress corrosion cracking (SCC), a problem that can cause blade release resulting in major damage to turbines, large repair costs, downtime, and the need to purchase replacement power.

Previously, two problems inhibited the success of UT inspection of blade attachments. First, the attachment hooks themselves cause strong signals that obscure the weaker signals caused by SCC. This system uses custom designed acoustic lenses to focus the UT so that it is possible to discriminate between hook-versus SCC signals.

Second, industry uses a wide variety of disk shapes, each of which require unique lenses and inspection plans. A vital part of this system is a set of CAD/CAM programs which enable efficient analysis, design, and manufacturing of the lens and inspection plans optimum for each disk.

Click here for a more detailed description of the advantages of beam focusing.

For additional information, please contact:

Mr. James Crane
NDE Science and Technology Division
Southwest Research Institute
6220 Culebra Road
P.O. Box 28510
San Antonio, Texas 78228-0510

(210) 522-5167 (Voice)
(210) 684-4822 (Fax)

crane@swrinde.nde.swri.edu

Back to NDE R&D Home Page

SwRI Home Page