Studying physics is an option. Sounds like you like mechanics and E&M. Physics degrees can be followed up with graduate level engineering ones quite easily, specially if you've chosen your electives wisely. Just a thought.
Physics is the definition of broad, and exploring different options...
Systems engineering (non-IT related) is a broad field, as I'm sure you are aware of. I've worked as one in the past doing Failure Mode Effects Analysis (FMEA) work for the External Tank program.
Systems can be Requirements Integration, which basically takes the requirements documents and...
LSU has a good Petroleum engineering program. Another career path is an API inspector. In-service inspections/repair of vessels and piping is big money. You could get API-510 certification, or just look on job search sites to see what is being asked for. Many times companies will pay for...
Thanks for the information. I am less than the 100,000 cycle threshold for high cycle fatigue for my piping systems. I see now that I should treat the displacement stress range differently than the pressure cycling Div II analysis.
My modeling program gives me allowable amplitude and max...
I don't know.
I think I'll just pick a worst case temperature swing, Amb to 105F, and add that expansion stress to my hoop stress with a factor of safety. Divide that number by two for the applied stress amplitude. So, [Exp(amb-T1) + 4*Hoop(0-P1)]/2 = Sa
Probably should do another case...
Thanks.
I don't have insight into how the stress model ramps the temperature from Ambient to T1. It seems the rate of heating is assuming the commodity of the pipe to be instantaneously changing over that range therefore the temp of the pipe to be doing the same.
If I went through the...
This is a Process Safety Management (PSM) issue with hydrogen gas lines. I've been tasked to look at fatigue of a long gas line. I know the designers took fatigue into account in their initial design, but I have no documentation which is ultimately needed.
I plan on applying a smooth bar...
I did a MSEE after a physics degree. I say it is an applied physics masters, but I have always worked as an 'engineer'. It's not the route for a design engineer though, or a PE of any sort. I took every electronics (circuits I&II, digital logic, electronics I&II, analog design, digital...
You were right, I missed the psig thing. You needed to divide by 1 psig to get the units to cancel, and essentially you did the same thing I was saying. I was thrown off by the 'Is this formula correct?'. Your units don't work out, but for psig your answer did.
So my 'No' was partially...
No. It would basically be setting two pv=nrt equations to each other, if you have the same temperature (but you'd different temps the same way). So p1v1=p2v2. p1=500psi, v1=53ft^3, p2=14.7psi. v2=(p1/p2)v1
Because for firebox material, which has been normalized, at a thickness over 2 inches the MDMT is somewhere above 60 degrees F. We have to be sure the metal temperature does not drop below that (for brittle fracture analysis since the vessels will see full pressure at ambient), but the site...
Thanks for the responses.
I still don't understand how I am going to lower my MDMT to our site CET by taking credit for the stress ratio at a lower pressure. It almost seems like I'm conservative for using effective thickness, ULW-16, and just assuming the layered vessel acts as monobloc...
Why not study physics? Material science, condensed matter, thermodynamics (statistical mechanics)...All hugely interesting and applicable fields. Combine that with some chemistry, and you'll be way ahead of the curve as far as advanced propulsion systems go.
Physics is really the mindset...
I have a question regarding the thickness used in MDMT calculations for layered vessels. The minimum design metal temperature is related to wall thickness in the ASME temperature exemption curves. For layered vessels, do you sum the thicknesses or use the thickest layer (usually inside shell)...
I see that I do not get the 15 degrees over the isothermal lines of the API650 map, thanks. The reason I am going to that map is because I don't have metal temperatures and the commodities are at ambient. I will explore metal temperature drop over the duration of a test though...
It is a pressure vessel for sure, operating at ~2600 psi right now. A 'code' vessel, well...no proof of that either. Tank was a poor choice of words.
The API650 reference comes from a bit of research on "The lowest (coldest) one-day mean atmospheric temperature..." entry in API579 [3.3.3] in...
I'm doing calculations for the re-rating of a pressure vessel (MAWP) based on MDMT/MAT. It's a 1965 vessel made from A-212 B firebox material. We don't have build records outside of calculations, so even though the vessel measures >2" thick we can't claim it was produced to fine grain...
Outdoor tank with an ambient commodity. Am I forced to API650 lowest one-day mean temperature chart plus 15 degrees? I don't have metal temperatures per say but I could get site temperatures over the last 5-10 years? If I do get a value for the lowest temp over that span, do I add 15 degrees...
