Recent content by buytree

Thanks a lot for your help. I have successfully completed both the Minimum thickness and the stiffener calculation. Thanks a lot for your motivation.

@ Q_Goest Thank you very much. I was assuming the Pa values are linear and came to a conclusion. It is so nice and kind of you to provide answers to all the questions. God bless you. Thanks a bunch again.

I did a sample calculation, I read in the ASME Sec VIII UG 28 that the allowable pressure should be higher than the applied pressure. If I choose a thickness that brings the allowable pressure higher than the applies pressure then my thickness is almost 1 inch which sounds ridiculous to me. If...

Thanks for your reply. After reading all the comments it makes more sense to me.

Let me tel it this way, when I use -14.69 Psig to calculate a 1100 mm OD & 16000 mm long duct minimum thickness under internal pressure (ASME B 31.3 par 304.1.2) I am getting a thickness of 2.43 mm which sound odd to me. The material I am using is Carbon Steel A 515 Grade B. Can anyone clarify?

Thank you Q_Goest for taking time to reply. What you wrote makes perfect sense. I have few more questions, 1. Problem statement, I am trying to select a thickness for a 1100 mm OD, 16000 mm long duct. It is maintained at vacuum pressure to suck the steam which is at higher pressure at the...

Thanks all for your reply. The value of vacuum pressure in psig is -14.696, but I am intended not to use a negative value in my calculation. Let me check where I am going wrong. Thanks again.

Googled it and I was getting the vacuum pressure is 29.921 in of HG (Gage). Corresponding conversion for the other units are zero, from here http://www.engineeringtoolbox.com/vacuum-converter-d_460.html" Can anyone please tel what's the vacuum pressure in psia and psig? Any comment will be...

I referred to the steps followed in ASME VIII Div 1. UG 27 Thickness of Shells under Internal Pressure used the formula in (1). which give .4954 mm + 3 mm. Am I using the right code or not? My question is, my duct is maintained under vacuum pressure to let the natural flow to the duct, from...

Thanks all for your response. @Travis King I felt the same way, the thickness is small. Even after adding the 20% more the t is 3.59 mm. I was thinking I have to add the effect of the external pressure on the duct (ASME B31.3 Sec 304.1.3), I am working on it.

I was reading the ASME B31.3 used the minimum thickness formula under 304.1.1, 304.1.2. Now I am not sure if I used the right vacuum pressure, I used 14.65 Psig? Can anyone comment if this is right? The material I used A 285 Grade B or A 515 Grade 60. I arrived at 0.56896 mm + 3 mm (corrosion...

It is 16000 mm long, 1100 mm OD.

How to calculate the minimum thickness of a duct which hold vacuum inside at 150 deg c? And what's the basic to select the stiffer size and distance between each stiffener. Thanks.

Answer to nvn: 1. The load is actually a tank of 19620N is sitting on top of the vertical standing beam. I assume the tank's load is applied over the cross section of the beam. (not on the centroid or at any offset). 2. It is a HW problem. 3. Yes you are right, A=4710 mm^2. 4. Yes Ke = 0.5, so...

Thanks. I got it.