I've noticed that pressure vessels built in the 1940s and 1950s were often shop-hydrotested at pressures much higher than 1.5X (now 1.3X) required by the Code and was curious to understand why. Some vessels that were carbon steel construction with design temperatures below 650 F (temperature...
Is there any requirement in ASME Section VIII, Div. 1 for rounding off nozzle IDs at the nozzle/shell intersection? If so, would this requirement apply to nozzles with an internal projection?
I've noticed that many manufacturers show a 1/8" radius on their nozzle details, but I'm not finding it...
Can anyone explain to me why beverage cans are fabricated exclusively from aluminum, while other goods (soups, vegetables, etc.) are usually packaged in steel cans?
Does it have something to do with carbonic acid corrosion? Just wondering.
Thanks,
-Christine
Form R-1 Report of Repair and Form R-2 Report of Alteration seem easy enough to understand, but under what circumstances would someone prepare a National Board Inspection Code Form R-3 Report of Parts Fabricated by Welding?
How can you fabricate new components per the NBIC when it isn't a...
Suppose you had a child that was in the process of choosing which career path to pursue. Knowing what you know now about the engineering profession, would you encourage them to pursue that field of study, assuming that they had the necessary skills to succeed as an engineer?
I think most of us...
How frequently do you find yourself using something that you learned in college and applying to your job as an engineer?
Personally, the only time I use something from school at my job is when I use AutoCAD, which is practically never. Everything else I had to learn on my own. I've certainly...
Why do kettle reboilers usually feature an "open" tube pitch, with p/d ratios on the order of 1.5 - 2.0 as opposed to 1.25 for conventional shell and tube exchangers? Vapor blanketing? Pressure drop? Thinner tubesheets?
Thanks.
-Christine
In a low-fin tube, is the I.D. typically made larger in the unfinned portion of the tube, as is shown in the diagram below:
http://www.furukawa.co.jp/copper/img/efl_ef1.gif
If so, why? I thought the fin grooves were machined out of a piece of tubing of uniform thickness.
Thanks.
-Christine
How does one calculate a 90 degree flanged & flued head in an ASME Section VIII-1 pressure vessel?
I need answers to the above when (a) the F&F heads act as an expansion joint and when (b) the F&F head is stationary, acting as a transition section.
Thanks,
Christine
Does anyone know of a good rule-of-thumb for estimating the costs of various corrosion-resistant alloys relative to the cost of carbon steel? Something fairly comprehensive would be helpful in coming up with rough order-of-magnitude cost estimates for various alloy alternatives.
Let's assume...
I've seen a couple of drawings of older pressure vessels (WWII era, IIRC) that mentioned the phrase "Hammer Test" in the section that listed all of the NDE. What kind of test could this be referring to?
-Christine
In my experience, all of the large air-cooled tubular heat exchangers I've seen have used aluminum finned tubes (tension-wrapped, embedded, extruded, etc.) to enhance heat transfer.
These finned tubes can be very expensive in comparison to bare tubes. I'm not sure what the effectiveness is of...
I seen a few shell and tube heat exchangers that were of the "bayonet" configuration, meaning that the tube-side fluid sees two coaxial passes, with the second tube pass being a larger diameter tube that surrounds the tube of the first pass.
With all of the potential problems of such a design...
I was just reading the "How many hours per week do you work?" thread and would like to ask all of you what percentage of those hours you spend at work are you actually *working* at your job, meaning that you're not chatting with your coworkers, or pretending to work when you're not, or posting...
What free Mechanical Engineering-related software programs have you used? It could be software that you use for a very specific job-related purpose or for a very general one, but it *must* be absolutely free.
Thanks,
-Christine
Someone once told me that their "rule of thumb" was that an engineer should not stay in the same job at the same company for more than five years, especially if it is early in his or her career. The reason being that it is important for an engineer to get the most learning out of their work...
For a given loading condition, is it ever possible to reduce the amount of stress seen in the part by machining off some of the material (ignoring of course the loading from the weight of the material that gets machined off)?
I ask because I noticed that the ASME Appendix 2 flange calculation...
In a 1-2 heat exchanger (one shell pass, two tube passes), is there any difference in the thermal performance if you make the first tube pass co-current and the second pass counter-current vs. making the first pass counter-current and the second pass co-current?
Are there any reasons to select...
If you're currently employed as an engineer, what percentage of your job duties are spent doing actual engineering work? By that I mean tasks that you couldn't do if you didn't have your engineering degree.
I'm a bit dissapointed that probably 80-90% of my job could be performed by someone...
