There are elastomers that will operate in an organic solvent environment at the temperature you're using them at, I remember finding one a few years ago but it was very expensive. Just a quick check on McMaster and I found a Viton® Fluoroelastomer that has a hardness of Durometer 55A and can...
gasketguru, Thanks for your reply. You are correct, because it's self energising every equation that bo is used in equals zero and the effect doesn't carry on in the later equations.
Thanks again everyone for your insite.
gasketguru, thanks for the tip.
How would I go about preform calculations per ASME BPVC Div. 1? I assume I would use Mandatory Appendix 2, but what bo value [basic gasket seating width (from Table 2-5.2)] would I use?
Thank you everyone for your thoughtful and insightful replies.
I assume the engineer was designing the flange to be an O-ring type instead of using a 1” x 0.5” x 87.75”OD gasket, that was he wouldn’t have an extreme amount of over-spill.
KevinNZ, it is a full penetration weld, it just has a ¼”...
I have a flange I’m looking at and the top half of it is a flat face flange while the bottom half is a ring joint flange (ring depth is 0.3”). The type of gasket the engineer is using is an elastomer with less than 75A shore Durometer with dimensions of: Gasket height=1.0” Gasket thickness=0.5”...
Hypothetically, I have a vertical pressure vessel that is split in half around the circumference in the middle and is connected by two extremely large bolted flanges. There is a manway on one of the halves of the pressure vessel and it is extremely close to the bolted flange, where the limit of...
MJCronin, I believe the drawings had full penetration welds on it.
My reasoning on why it didn't get welded correctly is because there are components inside the vessel that would make it almost impossible to weld correctly and that the welder was just lazy. We have a few vessels with this...
david339933 is correct. use your gauge pressure (barg) along with any static head pressured created by your fluid (assuming liquid service) that'll give you your internal pressure to be used in your calculations.
Hello everyone,
I have a pressure vessel designed to the ASME code and stamped for lethal service (L-stamp) it has been operating for over two decades with no real problems but during a recent shutdown and inspection it was discovered that an inlet/outlet pipe was not attached with a full...
Thank you everyone for all of your help and insight. I'm glad to know that someone (although rare) has addressed the air on the inside of the fillet welds.
Good morning everyone,
I have two questions. The first is about the ASME BPVC Section VIII Div. 1 code, and the second is about general engineering practice.
First question: In the ASME code a nozzle attached with an internal and external (double-sided) fillet weld, as shown in figure UG-40...
MFJewell,
Thank you for your input, I am looking into Roark's right now. my main concern on this design is if the skirt is a thin wall and the head is also a thin wall, (and assuming relatively heavy commodity) will the head of the pressure vessel have be stressed extremely high where it...
I am hoping the experience on here could point me in the right direction or give me a design formula that I can use to check if the thickness of the skirt is large enough.
I have tried looking in numerous design handbooks and I can only find equations for a skirt that is welded to the straight...
Here’s my situation. I have a relief valve with an inlet opening of ¾” but the line going to it is ½” [I know this configuration isn’t code compliant because of UG-135(b)(1)].
The problem I see with this configuration is, because the area increases at the relief valve inlet, the pressure in the...
Lingeshgdvg,
I used the "Pressure vessels handbook 10th Ed. by: Eugene F. Megyesy" and it walks you through a lug support calculation on page 109. The equations used are as follows (with the variables defined in the first picture of this thread):
Longitudinal Stress:
S_1=±QH/(DR^2 t) (C_1...
Thank you for all of your help. I looked under UHA and UNF and found what I was looking for.
For anyone else looking for this information, I made a quick list summarizing what is in the codebooks (Minimum temperature without needing impact testing)
ASME B31.3 (2016)
austenitic stainless...
Hello all,
I am trying to find a section in ASME BPVC Section VIII Div. 1 that explains how to lower a pressure vessel’s MDMT (without impact testing) when the material is not carbon or low alloy steel. I’ve read UCS-66, UCS-67, UCS-68, Figure UCS-66.1, and Figure UCS-66.2 but all of those...
@SnTMan
So as per UG-36(c)(3) all conditions (-a), (-b), (-c), and (-d) must be met [If they apply] to exclude that opening from a reinforcement calculation?
In my example above I can exclude UG-36(c)(3)(-b,-d) because it's not a threaded, studded, or expanded connection nor more than two...
Hello All,
My question is if you have two small nozzles (let’s just say the finished diameter is 2”) in a pressure vessel with a thin shell thickness (let’s say 0.25”) and they are relatively close together. Do you need do preform a calculation to determine if their centers are further away...
