(V) The Business Case for Non-destructive Testing: A Career Retrospective
As I explored the options, two different methods surfaced, which would theoretically meet the challenge. The first was eddy current testing. The equipment on the market at that time was not reliable. The second option was magnetic flux testing. A strong magnetic field is created around a test specimen. A discontinuity is detected when the flux changes values due to flux leakage. The manufacturer demonstrated reliable equipment and the method was adapted for Navy boiler tubes and automotive break line tubing.
As President at a different company, we employed MPI. This company made jet engine parts for the two major manufacturers of gas turbine engines. It was a quality requirement of both the Military and the FAA, that certain parts be subjected to magnetic particle inspection to assure there were no detectable unacceptable indications.
At the same company we made oil pumps for those engines. It was a requirement that every oil pump be x-rayed and evaluated to insure the absence of unacceptable indications.
Much later, in the 1990’s, I was a metallurgical consultant for a company processing ultrahigh strength low alloy tubing for automotive passenger door reinforcement beams. The process involved in-line eddy current testing after tube heat treatment for weld integrity and temper. By this time, the method and equipment were mature.
Finally, I witnessed the development of detecting various failure modes in assemblies at a very highly accelerated time window. This provided the manufacturer some level of confidence that its parts would survive without failure for the life of the design.