Hydrotest min. holding time

[kjy313]

I just remember that 30 minute is min. holding time in ASME Sec.VIII, Div.1. But I could not remember where this statment is.
Could anyone let me know the location of this statement?
Many thanks in advance.

 

[lostsailor]

UG-99 of VIII-1 does not specify a minimum hold time for hydrostatic test pressure.
Regards,
RLS

 

[metengr]

The AI will specify the hold time to allow for satisfactory inspection.

 

[22west]

ASME B31.3 section 345.2.2(a) says 10 minutes - if you are able to use that code as a reference.

 

[DSB123]

22west,
Thats a minimum time. It all depends on the time needed to fully inspect the system to ensure no leaks are present. For pipelines the BS8010 calls for 24 hour test.

 

[eyec]

as was mentioned 10 min seems to be used mainly in shop controlled tests prior to shipment/repair.

for in-place items, from a valve repair to the entire boiler, time would be dictated by how long it takes you to check the connection or walk the boiler down from top to bottom.

 

[GenB]

no, no, no
you rise to the required pressure test, then lower the pressure to the MAWP, then inspect for leaks for whatever time is required to inspect.
GB

 

[arcer]

Keep in mind guys, the question was related to ASME Sec VIII requirements, and metengr nailed it. It's the AI's call

 

[1969grad]

IMO, the hold time should be equal to the pressure test hold time of the piping into which the vessel is inserted.

Sometimes it is impractical to blank off the vessel for the site pressure test so that you test through the vessel. Most people avoid this but it does happen sometimes. So if the shop hold test is equal to the site piping hold time then you have some confidence that no problems will show up in the field.

As a practical matter if you go to the trouble to set up for a pressure test then why not test for at least an hour? Whether the hold time is 10 min (B31.3), 4 hours (B31.4) or up to 8 hours (B31.8) the difference in cost is small considering what you pay for the vessel.

 

[GenB]

PER CODESec VIII-1 required: 1.3 the MAWP)
you rise to the required pressure test, then lower the pressure to the MAWP, then the AI will inspect for leaks for whatever time is required to inspect.
if your AI does not know or support this, then he is wrong and the procedure needs to be discussed with his/her agency, (why not asking the National Board as well?)

 

[deanc]

It is not up to the AI to specify the hold time of the pressure test.

The Manufacturer must do this and the AI agrees.

There may be a desire to extend the 1.1,1.3,or1.5 pressure test for stress relief or to blunt cracks.

There needs to be adequate time for inspection for the AI AND the manufacturer at MAWP.

Review UG-90

 

[pvesseleng]

The main issue the sasifaction of AI Section VIII does not address any time

 

[VeryPicky]

Also, check the owner user specifications, they often specify minimum hydrotest duration. For vessels I recommend 1 hour stabilization at maximum pressure.

Putting Human Factor Back in Engineering

 

[jlr1408]

Our AI makes certain that we have a written hydrotest procedure and that we follow it. We set the minimum hold time in that procedure. If he wanted, he could require us to hold longer, but he never has.

If, as a buyer, you want a longer hold time, you should specify it in the user's design spec.

 

[pvesseleng]

kjy313,
There is no statement in ASME B&PV Code Section Div1 like you have specified.