Sonar Smarts: Monitoring Machines In a Sounder Way

JONESY is the fictional Navy sonar man, created by Tom Clancy, who could pick out traces of Soviet submarines where everyone else just heard noise. When the cold war ended, Jonesy went on to become a private contractor. I missed his submarine exploits until I found the equivalent on the factory floor.

It turns out that the skills needed to track subs are much like those needed to monitor machinery. Learn to read the special vibrations of rotating engine parts, and you can tell when something's wrong. Get really good and you can tell not only that a ball bearing is worn out, but which ball bearing.

People do the same today with other mechanical problems. If our car is shaking badly, it's a pretty good signal that it needs to go to the shop. Today's factory technicians use little boxes called portable data loggers to take readings of various parts every day or week or month. When something vibrates the wrong way, the technicians take a closer look.

The problem comes when the critical component is so hard to reach that the technician can't get his sensor close to it. Or when the machine is so loud it swallows the telltale whines of specific parts. Standard monitoring techniques also can't detect 20 percent of the more-difficult failures, such as a cracked fan blade or shaft.

That's where Jonesy comes in. Using high-grade math developed to track subs, a company called Monitoring Technology Corporation (MTC) has patented a way to pick up more subtle signals. The technology means monitoring systems can operate in rotating machines 1,000 times louder than before. And they can catch the other 20 percent of the problems that standard techniques don't, says Thomas McCloskey, manager of turbo machnery at the industry-funded Electric Power Research Institute.

Several industries are beginning to take notice. When Idaho Power replaced one of its plants last year, it installed MTC equipment on a 50-ton gearbox. The gearbox is critical because it sits between the turbine and the generator. Were it to fail, the whole plant would have to shut down.

In the electric-utility industry alone, maintenance and the associated downtime cost some $200 million a year, Mr. McCloskey says. Using MTC's continuous monitoring on the most critical components might save the industry 10 percent of that cost, he says. Other industries -- paper pulp, primary metals, chemical, petroleum, and others -- are beginning to use the technology too. MTC chairman Harry George predicts companies will spend more than $1 billion over the next decade to install such equipment.

Some industries, such as nuclear-power companies, have been doing round-the-clock monitoring for years. Fifteen years ago, it took a minicomputer and $50,000 or more in equipment to keep an eye on things, says Blake Van Hoy, a design specialist with Martin Marietta Energy Systems. Today, the same thing can be done with a laptop computer at one-tenth the cost.

Costs will fall further, these experts predict, as sensors and energy-converting devices called transducers are miniaturized into chips that transmit their data wirelessly. The technology might someday become practical for continuously monitoring the engine of a single-engine plane and other, smaller machines.

In the meantime, researchers are working on the next step of the process. Now that they can get the data, they're developing computers smart enough to analyze the information and alert operators only of suspicious events. All of which means that Jonesy's stint on the factory floor is probably temporary.

Eventually, he'll end up in a remote office somewhere, monitoring not one facility but dozens. It's a little cushier than he's used to and a lot less exciting than chasing Russians around the Pacific Ocean. But it's a big step forward. For all of us.

*Send comments via Internet (laurentb@delphi.com) or to CompuServe (70541,3654) or Prodigy (BXGN44A).