As the hemispherical end is seamless, the Longitudinal Joint Efficiency should be considered as a joint without imperfection i.e. Joint Efficiency E = 1. If you do 100% radiography of a welded joint it can be treated as a "perfect" joint, assuming no imperfection, and therefore no requirement...
An atmospheric vessel would be e.g. 1.034 BarG internal and 1.034 BarG external at the same time. Be careful when designing as these values are only acceptable when both internal & external pressures are the same, i.e. the pressure in the tank is equal to the pressure in the atmosphere. For...
Assuming you are designing to ASME VIII, Div 1 Design code - If the nozzle repad is made from 2 or more pieces & welded to together around the nozzle, you must apply an increased factor of safety to account for weaknesses caused by any additional joints. I think it has to be multiplied by 0.75...
Never heard of anyone doing this. We did have a rectangular vessel before & there was a requirement from the client to measure before and after testing to ensure no permanent deflection had occurred. Never been asked to do it on a cylindrical shell though so I doubt it's a design code...
Ah ok sorry, understood now. I don't think we will be allowed do that in this case but it's a good idea to keep in mind for future projects, especially if there was a higher margin between the design pressure & max. differential.
Thanks again,
MechD
OK I get you this time! So if my Jacket Design pressure was originally 8 Bar but my vessel could operate at -1, you're suggesting I could just drop the Jacket Design pressure to 7 Bar so that the max. differential falls within the original 8 Bar designed for.
So you feel that, even in the case...
Apologies Mike, I don't fully understand your question. I'm trying to work out if I should be hydrotesting the dimple jacket to 1.5 times Jacket Design Pressure or 1.5 times Max. Differential Pressure. Are you saying I should be hydrotesting to 1.5 times Max. Differential pressure? i.e. 1.5 x...
A leg reinforcement is not a pressure part. Only items which make up the "pressure envelope" are considered pressure parts (vessel shell, dished ends, cone ends, nozzles, pipe, flanges, blanks etc). What is your concern? That additional calculations or documentation or certification are...
Hi all,
I am currently struggling to agree with our Third Party Inspector on dimple jacket hydrotest requirements per ASME VIII, Div 1. I have always treated dimple jacket welded onto a pressure vessel as it's own unit, rather than another vessel chamber and / or combination unit. (For example...
Thanks BigInch but we're still in the early design stage so haven't bought any weldolets just yet.
Line pressure ranges from 4 - 16 bar. I've already emailed Bonney Forge, asking if they can certify a specific allowable pressure per fitting, or certify that it will match (or exceed) the...
Hi,
If I am using Bonney Forge Weldolets (specifically manufactured to MSS-SP-97 standards), are pressure calcs required for the fitting?
I have already found the straight pipe allowable pressure & corresponding wall thickness to EN13480-3. Are Weldolets certified to cover the pipe's...
