Method of inspecting a heat exchanger and computer program product for facilitating same

A method of verifying the identity of an individual heat exchanger tube for inspection of a steam generator for a nuclear power generation station, the steam generator including a plurality of tubes having ends fixed in a tubesheet, the method comprising:

• establishing a baseline for each tube of its location in the tubesheet and its signal pattern resulting at least in part from fixing the tube end in the tubesheet;
• providing a robotic arm coupled to a portion of the steam generator, the robotic arm including an end-effector with a data retrieval mechanism;
• inserting the data retrieval mechanism into a first identified tube;
• obtaining signal pattern data at an elevation proximate the first identified tube;
• comparing the signal pattern data obtained for the first identified tube with the baseline signal pattern resulting at least in part from fixing the tube end in the tubesheet for the first identified tube, in order to verify the correctness of the tube identification;
• and
• accepting the obtained signal pattern data if the correctness of the tube identification has been verified by the comparison.

A computer program product which, when implemented by a computer system having a programmable processor, a memory storage device and an output device, instructs the programmable processor of said computer system to execute a process for inspecting a heat exchanger having a plurality of tubes with ends fixed in a tubesheet, the process comprising the steps of:

• establishing a baseline for each tube of its location in the tubesheet and its unique signal pattern resulting at least in part from fixing the tube end in the tubesheet;
• recording the baseline for each tube in a database within the memory storage device of said computer system;
• identifying a first tube;
• inserting a data retrieval mechanism into the first identified tube;
• obtaining signal pattern data at an elevation proximate the first identified tube;
• comparing the signal pattern data obtained for the first identified tube with the baseline data for said tube, which is stored in the database, in order to verify the correctness of the tube identification;
• accepting the obtained signal pattern data if the correctness of the tube identification has been verified by the comparison or identifying another tube for comparison if the tube identification has not been verified by the comparison;
• updating the baseline data in the database based upon the signal pattern data obtained at the tube, tubesheet interface, for the identified tube after verifying the correct identification of said tube;
• and
• performing an operation on the identified and verified tube.