Rusty,

I have a customer that has two nickels on every bearing of their turbinge-generator to detect axial and radial vibration. When a nickel falls, they call me to come find out why.

This 40 cent solution has been in use since atleast 1990 and I am still trying to get my vibration trending to predict when the nickels will fall. If I predict the right day, the plant manager has promised to buy lunch for everyone. Needless to say, the pressure has been intense. (And I have bought them lunch every three months for over 16 years)

I've gotten it to within a 10 day period. As far as amplitude, each nickel is different. Vibration at one bearing effects a nickel on another. Plus the support fans and pumps transmit vibration to the turbine-generator structure.

On the plus side, the operators and mechanics are highly attentive to the vibrations. And I have enjoyed the challenge created by this little contest. It sure beats telling them something like "machine is normal, no action required". I know that every report gets read by everyone, and sometimes this is half the battle.

Using the nickel standard is a great way of getting others interested in vibration. It gives them a sense of participation, ownership and pride. All jokes aside (and they were pretty good ones), this is a communication tool that should be in the toolbox of every vibration guy, in my opinion.

Take Care,

I remember a heated discussion with two old mechanics in a refinery about the best diagnostic tool. Both mechanics dismissed the vibration data collector immediately. One argued that the nickel on edge was the best indicator. The other stated that he preferred to fill a Dixie cup with water, put the cup on the bearing housing and look for waves. No waves in the cup was his acceptance criteria.

With a progressive attitude like the 'old' mechanics had, it is lucky that they made it to be old. Maybe their old ideas made them look older than they were.

Many of those "old" mechanics know quite a bit about the machines they've been working on for years. I learned early in my career to weigh carefully their comments after they had listened to a bearing with the screw driver in the ear or they made other pronouncements. There's often some important information in those comments.

Jon
Spintelligent Labs

And over the years one has to learn to filter those comments. The boots that are worn in Texas help with the filtering and avoiding the b.s. - form follows function put the boots on.

Actually those old mechanics were pretty good. They just weren't early adopters of new technology. They trusted the tried and true.

And as Jon said above, listening to them paid dividends. They did know their machines.

Bill you're also right in that I did have to filter their input, not because they were trying to BS anyone but due to their scepticism of new approaches.

Don’t get me wrong. This would be a situation to treat them (and their opinions) with due respect.

However, as with everything, you need to evaluate the relevancy and worth of various comments. Just because someone can design a computer is no reason to let them under the hood of your car, similar with people arguing for either using a nickel or a cup of water to use as a vibration standard. As for me, give me a rattlesnake - if it hisses directly at the machine I know it is bad; if it rattles too, watch out.

Bill -

I certainly wasn't advocating that a cup of water or a nickel on edge is better than modern vibration analysis. Just trying to pass on a humorous experience.

That said, I would never discourage a mechanic from using a nickel, cup of water, a screwdriver, his fingertip or anything else he's comfortable using to assess the condition of equipment. Those tools / techniques might help someone make a call. And if it's what their comfortable with, it's better than them not making any assessment at all.

I had a local client who asked about installing some precision surfacing machinery, flatness better than 10^-8 inches, in an area near some ball mills. They placed a bucket of water on the floor and noticed waves from 1/8 to about 1/4 inch in height so called me to check it out. "Did I think they had a problem?"

Ja, you betcha! :-))

What would happen if while placing the nickel on edge it rolls off and falls into the shaft? This might be difficult to explain. Do nickels have safety approval for this application? I guess a screw driver is as good as a chisel, too - maybe better since it might work with screws, not to mention its use in vibration analysis.

Mr. Bill
Now there are three -- Sam, Motor Doc and you.

Bill, not a problem down here as our dollar is half yours anyway we'd have to cut the nickel in half!

Regards,
Mike.

quote:

Mr. Bill
Now there are three -- Sam, Motor Doc and you.

What am I missing here? Are you on medication for this, Barry?

Bill,

Take my word for it...leave it alone and hope it goes away.

Danny

Danny,

I looked at some of the other posts from the past. Maybe, he can't count, because you would make it 4. Could there be more?

The only thing that I can see is that perhaps I made light of his favorite measurement instrument. Perhaps, he has a stock of old nickels for sell. I really have no idea what got into Mr. Barry (the vibration person formerly known as Crawdad).

Hi Folks!!!! Smile.

It's always nice to see what other members look like

When they said apes, I thought it was just the long arms we get from hauling all that heavy test equipment. I had no idea it went beyond that. But I would have thought that Ralph would be a silverback by now!

Jon
Spintelligent Labs

Bill,

I think he's only counting the smart guys not the smart alecks.

Danny

This message has been edited. Last edited by: Danny Harvey,

quote:

But I would have thought that Ralph would be a silverback by now!

Maybe this is just an old picture, huh?

Barry,

I think my esteemed collegues are in a league above me; but, thanks for the compliment. However, I don't think you'll ever be a part of any group of more than one until you die. You should have expert status on NFPA 70E and wanting to be a major contributor in R & D. And get back on the meds! Who said nobody's perfect; obvisously they never met you.