Use of original bolts for hydrotest

[Steve.sw90]

Dear all,
Good morning.
As per U1 (e) (3)even bolts for manways and handholes fall under scope of ASME section VIII Div.I.
We are buying standard ASME bolts, since these are standard items do we have to use original bolts for hydrotest.
If not please give code reference or interpretation.

Regards,
Stephen

 

[Dhurjati Sen]

The purpose of hydro-test is to ensure the sturdiness of the weld joints. For all flange joints, it is expected to use suitable bolts and gaskets so that a visual inspection for a sufficient time could be made without any accidents / incidents.
Since you are buying standard bolts, why not use them for hydro-test too?

 

[metengr]

You do not need to use the same or original supplied bolts for hydrostatic testing but you do for final assembly and before stamping.

 

[Steve.sw90]

We have bought standard bolts, but not yet arrived in shop.
AI is claiming that as per U1 (e)(3) bolts are in scope of ASME and shall be used during hydrotest to confirm that bolts are suitable for application.

 

[LittleInch]

Perhaps it's me but can you use engineering terms for these bolts please?

What material. yield strength and size are "original" bolts?
What are "standard" or "ASME" bolts?

What is the difference in strength, size, ???

The same material and size of bolts should be the same between hydro and operation but not, IMHO, necessarily the same actual bolt. Otherwise you are not testing the completed item.

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

 

[DekDee]

I am asking this purely to learn from you more experienced vessel guys.

Hypothetically, you manufacture a pressure vessel with 11 x nozzles and all of them will have pipework to be connected at a later date by a different company on site.
It is your role as the vessel manufacturer to confirm the integrity of all connections (welded or otherwise) up to the flange faces of all 11 x nozzles.
What does the size or material of the bolts (or the blind flanges)have to do with the actual connections being tested ? - obviously they must be sufficient to provide a safe hydrotest but ultimately they are only temporary.

 

[SnTMan]

DekDee, you are pretty much correct, as the fabricator, your scope is to the face of flange, and yes, you should be able to use whatever blinds, gaskets and bolting get you thru the hydro.

However, the AI's wishes usually must be accommodated some way or another. I notice the OP dies not state whether these are piping connections or maybe manways or hand holes.

And yeah, LittleInch, it would be nice if we knew what we were talking about

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[LittleInch]

He kind of implies that these are the manways and hand holes so they would be the permanent bolts and flanges etc. All other nozzles, yes, they would all be removed after hydro to allow for actual connection of the piping.

It's pretty rare to have a vessel without at least one manhole or hand hole with a permanent blind flange supplied by the PV supplier.

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

 

[DekDee]

Thanks for the explanation guys.