BigInch
Thats true what you saying about stress. But I mean strains
From mechanics of materials we have the following:
?H=pD/2t
?L=pD/4t
From Hooke's law:
?H=1/E(?H-??L)
?L=1/E(?L-??H)
let's assume that hoop stress is 2 (Mpa, ksi whatever you want)
axial must be equal 1
after...
BrianCNTFM
I agree with you. Although pressure forces are rather in magnitude of hundreds they are far lesser than thermal and from earthquake and of course those which can arise during not carefull assembly. But you dont know Germans they are more strict than API 686.
Regards
papiesz
Big Inch,
That is not true.
There is not any contraction due to pressure. Such situation exists in uniaxial tansion. You can observe it on tensile test machine where you can observe cross section area reduction.
In case of pipe you have membrane stress and strain state in which both streses...
Hello again
Pressure elnogation is not 13% of thermal. I made mistake, it is roughly 1/13 which is 7%. So it is less significant.
I'm sorry. This is because here is 11 PM, and I focus too much on my English instead of the problem.
papiesz
Lucky you, gentlemen
You can buy this book directly from ASME store. I come from Poland and I would have to buy it via English resseler which is 1.5 times more expensive and in addition he does not respect Polish credit cards. World more and more resembles jungle to me.
By the way I read Mr...
Varsamidis
I meant elongation of straight pipe and elbow centerline under internal pressure. As I know Bourdon effect is linked with tendency of pipe bends to open under pressure. Ovalisation (if exists as a result of fabrication)intensify that tendency.
Pipe stress software (autopipe...
Hi all
I have to analyse feedwater pumps piping according to B31.1. Design pressure of discharge pipe is 23.4 MPa. Calcs during FEED was made by another company using Caesar II. They calculated standard operating cases W+P1+T1 but Bourdon option was set to "none" which results in no...
Hello again
I see that "my thread" got second life. I'm glad especially seeing John and other forum giants comments. It is very valuable for me.
I have almost 4 years experience in B31.3 calcs in Autopipe. Now I turned to B31.1 still autopipe but first stage of project was done by another...
Dear all
Anyone knows why Autopipe when calculating sustained stress according to B31.1 uses corroded wall thickness by default. This is of course more conservative but ASME B31.1 para 104.8.1 states that nominal thickness should be taken into calculation. Also Caesar II takes nominal thickness...
Mr Demir
I've recently found your post on this forum. I foun this because I searched answers for the same question you asked year ago. It was a problem why bolt stress for seatnig condition for class 150 ASME flanges is in most flange sizes above allowable.
I work for company where...
