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Hydrostatic Test of Pipe

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vendorinspector

Nuclear
Aug 20, 2009
1
When using ASTM A 530/530M or A450/450M - is deionized water required for the hydrostatic test?
 
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No. This is a specific process detail that should be discussed by the purchaser and agreed to be the vendor. One can use even raw river water for hydrotesting.
 
My understanding is that since hydro test has water sitting still in the pipes, the amount of minerals inside typical natural source of 'clean' water is not enough to cause any significant corrosion.
It is a different case than running water during operation in which fresh minerals are being continuously brought in and accumulated corrosion happens for long term so good water quality is then required.
 
Keep in mind as well that hydrotest is at most a few hours, maybe a day if tis left overnight for some reason, in short corrosion wont happen that fast. (or really should not)

Just go ahead and hydrotest as per normal unelss the buyer insists on somethign else, then just make sure they pay for the out of the ordinary test.

You might want to make sure the piping/vessel is cleand out well after though, purge it with air or run a pig through piping.
 
Another thing to keep in mind is that the more dissolved air there is in the water, the more problems you'll have maintaining a test. Whenever I've used surface-water for tests I've filled the system till water came out the high-point vents and then let it sit with the vents open for 24 hours adding water as necessary to keep the vents full to the top. After the soak time the test always goes smoother than it would have without the soak time.

David
 
If the client lets you wait that long, soaking and venting is a great idea. Look for temperature equalizing problems also. Sometimes even overnight is long enough to heat up/cool down the pipes to the ater temperature.

get your CLIENT's complete agreement with the test protocol and the test fluids. Using DI water is essential sometimes, useless others. Using salt or choline filled "street water" in a steam system or HP gas system might require hours or days of flushing, or it might be completely irrelevant to future ops.

Regardless, it always seems that by the time the hydro-test is scheduled, the overall schedule is behind from other problems, and the testing is always under pressure even before they fill the pipes "to get it finished faster"
 
Normally Use Raw river water, But Sometimes required By Client. Remember after hydro-test, do purge with N2 or etc inside pipe.
 
I've done dozens of hydro's (mostly with river water) and have never done an after purge with nitrogen. Seems like a major waste of time and money. If you run drying pigs (with air) until you don't get any more water you won't have problems.

David
 
I agree with David, its pretty rare to have system that sensitive that you need ot purge with N2, but then if the client insists on it, it is at their cost, just make sure you let them know its an extra cost and not somethign thats typically done.
 
No ASME Code requirement, there are recomendations found in NACE
for C/S it is safe to use raw potable water but for SS it is better and safer with DI water.
If raw water is used, drain the vessel asapossibe and air dry it.
genb
 
vendorinspector,
A-450/A530 applies to carbon, low alloy and stainless steel grades. Which grade(s)of material will be hydrotested? How long will the tubes be stored after hydrotest before installation or placed in service? When testing austenitic stainles, low chloride containing water should be employed for the hydrotest or low chloride water must be used for rinsing.

Are you testing boiler components for Heat Recovery Steam Generating equipment?

 
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