Hydro Testing Inconel 625 lined Spool Piece

[mayur1787]

Can anyone one advise on whether demineralised water or water with an inhibitor is more suitable for hydro testing a spool lined with Inconel 625?

 

[LittleInch]

I thought the whole purpose of Inconel 625 was that it was resistant to most corrosive fluids.

Therefore you should be able to test it in virtually any liquid surely.

Demin water is for stainless systems / Nickel alloys to avoid chloride contamination.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[GD2]

mayur1787,
Inconel 625 is widely used for sea-water service which is very corrosive. Why would you think of DM water for testing? BTW, what's the base pipe made of?

Ganga D. Deka, P. Eng
Canada

 

[UDDBOY]

What would be better than Demin water?

 

[racookpe1978]

Demin water is much more expensive, harder to provide for the hydro test in a typical construction/outage schedule with limited plant services on-line.

But, if the water is to be "left in system" after the hydro test until commissioning and startup, and if demin water is required for the running plant, then you might consider using demin water. But, I'd rather use the much cheaper regular city tap water for everything up to the final system flush and cleaning. Then turn over a drained and inspected system (no chance for leaks during the outage after the hydro, no LOTO problems and continuous monitoring needed!) for the operations people to refill for startup with demin water once everything is starting up.