Hydroelectric Water Tower Corrosion
Hydroelectric Water Tower Corrosion
(OP)
I'll be inspecting and determining the integrity of a very old (installed 1965) surge tank used in a hydroelectric project.
The latest drawings on the project are all dated to 1965, and the tank is stated to have a corrosion allowance of 3/32".
Since this tank is not under pressure, I believe this corrosion allowance was arbitrarily picked. Also, since it is an old tank there will definitely be significant corrosion. Not sure if I should just stick to what was picked by the engineer that originally stamped the drawings, or if I should make a more specialized recommendation.
Are there any detailed reports or studies that have dealt with these non-code, non-pressurized tanks? If I see a single point with corrosion greater than 3/32" is that enough to condemn the tank, or at least require a new coating in the area?
The latest drawings on the project are all dated to 1965, and the tank is stated to have a corrosion allowance of 3/32".
Since this tank is not under pressure, I believe this corrosion allowance was arbitrarily picked. Also, since it is an old tank there will definitely be significant corrosion. Not sure if I should just stick to what was picked by the engineer that originally stamped the drawings, or if I should make a more specialized recommendation.
Are there any detailed reports or studies that have dealt with these non-code, non-pressurized tanks? If I see a single point with corrosion greater than 3/32" is that enough to condemn the tank, or at least require a new coating in the area?
RE: Hydroelectric Water Tower Corrosion
Anyway, check API 510 for guidance.
DHURJATI SEN
Kolkata, India
RE: Hydroelectric Water Tower Corrosion
luis
RE: Hydroelectric Water Tower Corrosion
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P.E. Metallurgy, consulting work welcomed
RE: Hydroelectric Water Tower Corrosion
The UT crew is proposing to use a pencil probe that gives data in a very small area and can get around the rust.
RE: Hydroelectric Water Tower Corrosion
https://rules.dnvgl.com/docs/pdf/dnvgl/cg/2016-02/...
RE: Hydroelectric Water Tower Corrosion
luis
RE: Hydroelectric Water Tower Corrosion
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed
RE: Hydroelectric Water Tower Corrosion
Hard luck. Tell them they need to remove the insulation if they want a report that's actually going to be useful.
Operations need to get their head out of their behind and do things which make the inspection possible, not be obstructive.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Hydroelectric Water Tower Corrosion
The dam will be shutdown and the tank will be drained anyway. So if the corrosion is not as bad as expected, UT from the inside should not be an issue.
Did not know tanks would have inspection ports, once on site I'll look around for these. The tank is quite large (40' diameter x 100' height).
Mostly wondering about the corrosion allowance on non-code tanks. The 15-20% rule is similar to the initially stated corrosion allowance on the 1965 drawing so I might just go with that.
RE: Hydroelectric Water Tower Corrosion