"Ignoramus29516" wrote in message
...
SNIP
| You'd be money ahead to find a place that can do it for you. Don't
know
| what kind of place that would be, but perhaps ask and industrial supply
who
| uses them.
|
|
| Thanks Carl. I thought that the OP talked about some sort of magnetic
| sensor, not ultrasound.
|
| i

Oh, and if you want to, it might be worth having the inside of the tank
sealed as well. You can have it done, radiators shops can do it, or you can
buy kits from Eastwood and do it yourself. The DIY kit likely doesn't cost
that much, either, relatively speaking.

There are and were all kinds of sensors that do that sort of thing.
Ultrasonic is the most accurate and most modern method nowadays. Out in my
tool chest I have what's called a pit gauge, which is a cool tool for
measuring the depth of a pit or depression, originally for the inside of a
boiler. There's a lever that shows the pit depth is % for different
thickness walls, in addition to the raw depth figure. You obviously have to
be inside the boiler to use it, so I imagine it was a rather unpleasant job!

The old boiler guys have little hammers they go around and ping on the
walls and listen to the thickness of the vessel wall. That's a real skill!