Fatigue assessment in vertical Vessel supported by brackets

[raulcc]

thread794-501203
Dear All,
I hope this thread finds you well.

I have a question regarding the necessity of performing a Fatigue assessment

Currently, I am designing a vessel with the design pressure and temperature of 4 4barg and 80C. Nothing special, but operate in batches a fluid that is heavier than water by 20%. The vessel is filled up to 90% level, and then emptied to 15% level, every 20 min. this gives 72 cycles per day @ constant pressure and temperature.

The load on the Brackets is about 10 tons per support, (total of 40 tons when 90% full)

What do you think should be done? it is necessary the fatigue assessment in this case.

Thanks for your time.

Kind regards,
RACC.

 

[TGS4]

72 cycles a day for 25 years is 657,000 cycles. That’s less than the 1,000,000 that would make a fatigue analysis mandatory, but that’s still a substantial number of cycles. At a bare minimum, I recommend performing a Method B fatigue screening assessment to determine whether or not to perform a full on fatigue analysis.

 

[r6155]

Grind fillet welds to a radius and liquid Penetrant examination.

Regards

 

[raulcc]

Thanks for your reply's.