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Pneumatic test of atmospheric vessel

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ElCidCampeador

Mechanical
May 14, 2015
269
Hello, I have a horizontal vessel O.D.=2,5m Lg.=4m Thk.5mm material carbon steel.
Design/operating pressure=atm, fluid=oil.
My client wants to check leakage with a pneumatic test. What pressure test do you suggest to adopt?

There is no construction code, it's only good construction pratice and hydrotest is not accepted. What do you say? Thanks
 
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So you have a no code vessel that stores oil. Let’s hear more of it. What type of oil- light, heavy, temperature, vapour pressure, Relief arrangement if any?

GDD
Canada
 
Let’s have a final look at this. Worst case scenario, Let’s assume it’s an API 12F atmospheric tank and apply ASME V.
EiCidCampedor will do the following:
-Calculate the capacity in BBL.
-Look up API 12F and determine the design pressure corresponding to calculated BBL. Most likely, it will be 1 psi.
Pneumatic test at 25% of design pressure, which will be 0.25 psi.

Does all agree on this?



GDD
Canada
 
@ GD2
You are very confused. Please read the initial post ElCidCampeador (Mechanical)(OP)7 Jul 21 07:47

Regards
 
I don't think I'd bother with 1/4 psi....

The problem with sloppy work is that the supply FAR EXCEEDS the demand
 
r6155,
I understand this way:
The originator has a horizonal atmospheric tank with no construction code. He/she now wants to do a pneumatic test. He/she is asking what test pressure to be used.
The forum agrees to adopt ASME V rule. ASME V rules say test at 25% of the design pressure.
I agree to this point.
Now, the question is how to establish the design pressure.
With no code of construction, I will take reference to API 12D and 12F where both are atmospheric tanks, even if our case is a horizontal one.
Both standards establishes design pressure based on size/barrels of oil.
A quick calc gives me the tank capacity less that 500 bbl (~490 bb;).
API 12F will give a design pressure of 1 psi and API 12D even less. Both these standards reference ASME IX for welding procedure and qualification.

With no data on construction code of this tank, we need to apply our best engineering knowledge and judgement.

API 12D allows air test at 1.5 times the design pressure (I don't have the latest version).

I am not sure about the ASME V rule - most likely, this rule applies to non-atmospheric ASME vessels.

Under these situations, will it be a good practice to start the test at 1 psi, then ramp up to 1.5 psi?



GDD
Canada
 
EiCidCapedor,

By the way, can you give us some info on the type of oil the tank will handle? It might give us some clue to the nearest construction code.

GDD
Canada
 
@ GD2
You are extremely confused.
Forget API 12 , ASME, and the type of oil.
Do you understand the purpose of hydrostatic test and the leak test?
Did you witness hydrostatic test or leak leak test any time?

Regards
 
I hope that by now ElCidCampeador has performed his test and moved on :)

The problem with sloppy work is that the supply FAR EXCEEDS the demand
 
Hope he wasn't standing too close....

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