hydrostatic test period
hydrostatic test period
(OP)
Dears;
Respecting hydrostatic test period, nevertheless, I have used a different periods I have faced through my experiences, the code for the facilities does not have a specific testing period for any of them.
So, would you please specify the holding time for the hydrostatic test required for;
1/ API 650 Storage Tank?
2/ ASME B31.4 Pipeline?
3/ ASME B31.3 Piping?
4/ ASME B31.8 Pipeline?
4/ ASME VII Div.1 Pressure Vessel?
Note:
For ASME B31.4 the code specify ≥4 hours for hope stress >20% of SMYS & <4 hours for hope stress ≤20% of SMYS, however it does not specify to which limit. (also ASME B 31.8 specify ≥2 hours but also not specify to which limit).
Respecting hydrostatic test period, nevertheless, I have used a different periods I have faced through my experiences, the code for the facilities does not have a specific testing period for any of them.
So, would you please specify the holding time for the hydrostatic test required for;
1/ API 650 Storage Tank?
2/ ASME B31.4 Pipeline?
3/ ASME B31.3 Piping?
4/ ASME B31.8 Pipeline?
4/ ASME VII Div.1 Pressure Vessel?
Note:
For ASME B31.4 the code specify ≥4 hours for hope stress >20% of SMYS & <4 hours for hope stress ≤20% of SMYS, however it does not specify to which limit. (also ASME B 31.8 specify ≥2 hours but also not specify to which limit).
Mohd Yaseen
RE: hydrostatic test period
1/ API 650 Storage Tank? -min 24 hours (7.3.6.5 b 5)
2/ ASME B31.4 Pipeline? As you said, min of 4 hours
3/ ASME B31.3 Piping? Well 31.3 is really piping not a pipeline, and it requires visual inspection of all welds. At least 10 minutes, but the inspection usually takes longer.
4/ ASME B31.8 Pipeline? Min 2 hours of a stabilized pressure
4/ ASME VII Div.1 Pressure Vessel? don't know - 2 hours?
The key is to work ut why you're doing the test.
Is it a strength test ( in which case a short period is enough) or is it really a leak test, in which case you need to take as long as it takes to have stable pressure, or a pressure variation you can explain by means of temperature changes.
Each client will be different and have their own thoughts / procedures.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: hydrostatic test period
thanks for your cooperation & respond
agree with you that strength test (larger than leak test pressure) will have take shorter testing period compare to leak testing period. I have a faith that the testing periods mentioned in the code (mentioned in your responds) are implying both of them (strength & leak) testing period. My question is: what the % of each (for example 4 hours for pipeline, how much of this period for strength test & how much of this period for leak test)?
usually the leak test = 80% of the strength test pressure (or = design pressure), so do you think their testing periods should be accounted in the same manner also?
Note: of course the test need to take a sufficient time to assure from your facility strengthen & quality, but the contractors are controversy with the Client a lot in case of no specific statement stated in the used references. for example, pipeline with 10KM length should never has testing period similar to pipeline with 50KM length, but as long the code specifying ≥4 hours, the contractor arguing & negate the use of 24hours period (for example) for the pipeline with 50KM length). I think the codes have a leak on the specifying the range for each testing period (to which extend).
Mohd Yaseen