2 replies to this topic

[Art Montemayor]

thyme:

Jeff H is emphasizing the important, basic points in presenting your query. Without specifics, you're going to generate a lot of guessing, speculation, and conjectures - most of which may not even apply to your specific problem. Allow me to give you some specific examples:

1) If you have a horizontal tank installation, do you foresee or plan to employ steel saddles? Or will you employ concrete supports? The length/diameter ratio (L/D) is critical because it will impact on the number and size of supports you have to furnish due to the bending of the vessel (considering the fluid & its own weight ).

2) If you have a vertical, cylindrical tower, do you plan to use a skirt on the vessel? or do you intend to hang it from structural steel with lugs? Towers are very sensitive to wind loadings, seismic loadings, and flexure - the spaghettii noodle effect as the L/D gets higher and higher.

3) If you have a spherical vessel, you have a totally different (and perhaps more difficult) problem. Wind loadings, leg supports, vessel movement and expansion are some of the problems that have to be addressed.

If you are a Chemical Engineering student, you are laboring under the lack of specific mechanical vessel design that is so needed by young ChEs out in the process plants, working with these type of vessels. Unfortunately for you and your classmates, I have no academic solution other than to recommend that you take mechanical engineering electives in the subject matter. I wish I had because I would have been spared a lot of sleepless nights and hair-pulling out in industry after I graduated. I had to purchase my ME books and make diligent use of my engineering mentor (who fortunately happened to be an ME). Today, the era of mentors is no longer available to most young engineers and there is little any of us can do about that for the moment. I would recommend you obtain a mentor, purchase and digest mechanical engineering vessel design textbooks, ask countless questions on the subject to the experienced engineers around you, and always concentrate on the basics that Jeff H cited:

"What is the vessel's function?? What chemicals will it hold, process and under what conditions?"

Don't forget that you have to not only address what you need the vessel to do; you also have to address what the vessel needs from you: safe access - both external & internal; correct and safe drainage; correct number and size of nozzles; ladders, platforms, railings, lighting, utilities, etc.

I hope this helps add to your understanding of the subject.