Design of rectangular pressure vessel with orthogonal stiffeners 2

[Pritam92]

hi!
i need some help on design of non circular pressure vessel, specifically rectangular vessels with orthogonal stiffeners under external pressure. i have got some design rules from ASME Sec VIII, Div-1 appendix 13 , but there is no formula given for orthogonal stiffeners. can you guys please help on design procedure and spacing between stiffeners etc??

 

[JAS]

Hi, refer "Formula for Stress and Strain" by "Roarks and Young" for the design of Rectangular Tanks.

 

[MJCronin]

Search this forum with the terms "rectangular storage tanks"

I could find no discussion related to rectangular tanks with external pressure ... except this one ..

https://www.eng-tips.com/viewthread.cfm?qid=27937

This might also help ...

https://www.scribd.com/doc/299626833/Rectangular-Tank-Design-Exel

MJCronin
Sr. Process Engineer

 

[IFRs]

I have a reference at home that I'm sure is entitled "Design of Rectangular Bins" or something very similar that I used when reviewing some buried rectangular oil tanks of substantial size. I won't be home for a few days, if you can hold on...

 

[Pritam92]

Dear JAS and MJCronin,

Thank you for this link. This system appears to be exactly what i am looking for.

 

[MJCronin]

Tell us more details about you design ..

What is the MOC, size of the tank and range of positive an negative design pressures ?

How will you test and certify the tank ???

MJCronin
Sr. Process Engineer

 

[robyengIT]

"Design of flat plate structures - API Bulletin 2V - 3rd edition, June 2004"
section 3 : plates
section 4 : stiffeners
section 5 : stiffened panels

 

[Pritam92]

We have a existing steel cabin(IS 2062) which is always kept at a 30 mbar gauge pressure. The size of tank is 3.5m*5m*5.5 m.
It is already designed and erected at site with 6 mm plate thickness along with orthogonal stiffeners(ISMC 150 BOX) .

During pressure test two bulged are observed on the edge. So recheck was carried out by me. I found that it can withstand around 80 mbar with existing design. So can you guys guess what may be the reason???

 

[Dhurjati Sen]

Dear Pritam92,

IS 2062 (like ASTM A 36) is not a very high quality plate (like ASTM A 516). Check for laminations at the bulged locations.

Regards.

DHURJATI SEN
Kolkata, India