Bent in shell of pressure vessel (residual stresses)
Bent in shell of pressure vessel (residual stresses)
(OP)
I have a pressure vessel with bent in its shell. So I want to evaluate this vessel acc. ASME BPVC VIII div.2 Part 5 in elastic-plastic method.
My way-
1) I build a geometry model of the vessel with the bent.
2) Use the appropriate procedure describing in ASME
Here I have a question-
When the bent was created, it have become to have residual stresses, which I haven`t taken into account. So my evaluation of vessel is wrong?
So, to evaluate this vessel right-
1)I have to model the vessel WITHOUT the bent, then to model the creation of bent (e.g. by indentor). So I get residual stresses and then
2) Use the appropriate procedure describing in ASME
Am I right?
Thanks for advance!
My way-
1) I build a geometry model of the vessel with the bent.
2) Use the appropriate procedure describing in ASME
Here I have a question-
When the bent was created, it have become to have residual stresses, which I haven`t taken into account. So my evaluation of vessel is wrong?
So, to evaluate this vessel right-
1)I have to model the vessel WITHOUT the bent, then to model the creation of bent (e.g. by indentor). So I get residual stresses and then
2) Use the appropriate procedure describing in ASME
Am I right?
Thanks for advance!





RE: Bent in shell of pressure vessel (residual stresses)
RE: Bent in shell of pressure vessel (residual stresses)
How big is the defect ???
Can you give us pictures ?
MJCronin
Sr. Process Engineer
RE: Bent in shell of pressure vessel (residual stresses)
OK, thanks for invitation, I will try to compare.
to MJCronin-
Here pictures:
sizes of bents
http://files.engineering.com/getfile.aspx?folder=d....
a general form
http://files.engineering.com/getfile.aspx?folder=c...
angle distribution map (degrees)
http://files.engineering.com/getfile.aspx?folder=c...
Diameter is 2400 mm and thickness is 3 mm. Pressure is 0.3 MPa.
How can you predict whether we should model residual stresses or not? By experience?
Thank you
RE: Bent in shell of pressure vessel (residual stresses)
Daniel Breyer
Inspection Engineer
http://lnkd.in/dFcQA-w
RE: Bent in shell of pressure vessel (residual stresses)
What do the bends and dents look like? The actual shape of the edges of the bent steel are the stress risers, and the physical shape of each indent is (I am assuming the dents go "into" the tank!) very important. Some curves may be shallow and not very important even though they are larger, another very important if the shape creates a sharper kink.