Tilted compression (stiffener) ring
Tilted compression (stiffener) ring
(OP)
Dear All
We have tanks with a deformed top compression ring. This took place in a three out of four 35 years old single cladded shell, fixed roof tanks.(D = 32 m, H = 18 m).
The cause?
in my opinion it could be:
1) an uneven settlement
2) a wrong erection procedure (i.e., it is there from day one but no one noticed as the tanks are insulated)
No shell buckling or bulging
The vertical side of the stiffener beam is tilted radially inward for 12 to 25 mm for 40% of the circumference. see images plz.
Your support is highly appreciated.
We have tanks with a deformed top compression ring. This took place in a three out of four 35 years old single cladded shell, fixed roof tanks.(D = 32 m, H = 18 m).
The cause?
in my opinion it could be:
1) an uneven settlement
2) a wrong erection procedure (i.e., it is there from day one but no one noticed as the tanks are insulated)
No shell buckling or bulging
The vertical side of the stiffener beam is tilted radially inward for 12 to 25 mm for 40% of the circumference. see images plz.
Your support is highly appreciated.


RE: Tilted compression (stiffener) ring
RE: Tilted compression (stiffener) ring
The information that you provided is not enough to see the case.. Pls provide more info . to get valuable comments such as ; The design and operating temperature and pressure, roof supporting system, connection detail of roof plate to ring , some settlement measurements, the deformation is local or not, insulation and cladding system, some descriptive pictures..
With the info. that you provided , the posts that you will receive will be only guessing game... I will start the first guess;
The internal pressure built up and the roof plate ovalized and developed radial tension all around ..the roof plate connection to sloped stiffener experienced bending ..
RE: Tilted compression (stiffener) ring
Has there ever been a seismic event in your area ?
Where is the tank located ?
Can you provide pictures ?
MJCronin
Sr. Process Engineer
RE: Tilted compression (stiffener) ring
RE: Tilted compression (stiffener) ring
DHURJATI SEN