Centre of gravity 1

[Iceman7]

How to calculate the centre of gravity for a vessel?.....Please help

 

[LittleInch]

Break your vessel into its components, work out its weight and that shapes C of G, add any particular weights attached, such as valves then sum them all up. based on some sort of grid system.

Or ask the CAD/3D system.

This assumes the vessel is empty, if not add weight of contents.

If you provide a bit more info such as a drawing or picture of your vessel it would help.

https://www.grc.nasa.gov/

http://www/k-12/airplane/cg.html

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[SnTMan]

Dig out the statics or strength of materials textbooks. That is how it is done, even by software.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[JStephen]

I believe that concept was introduced in Calculus 1, and is carried on from there.

 

[chicopee]

You are correct JStephen.

 

[Iceman7]

Thanks everyone for your reply.....

 

[Iceman7]

According to UCS-79 (75*Tnom/Rf)*(1-Rf/Ro)
Tnom= Noinal thickness
Rf=final mean radius
Ro=Original mean radius
How do I determine the values for Ro and Rf.
For eg- what would be the Ro and Rf for a vessel with dia 6'(1828.8mm) and thk 0.5"(12.7mm)

Attached is a vessel drawing pls help in determining Ro and Rf values.

Also help with determining its Cg ignore weight of the nozzles or any attachments just consider shell and D'Ends

Thankyou...

 

[LittleInch]

No idea what that equation is trying to calculate or its units, but looking at your drawing, if you're just looking at the vessel without considering the nozzles or the manway or the saddle and supports, the CoG would appear to be in the geometric centre of the vessel, i.e. 7' 6 from the tan line and in the centre of the vessel when looking end on. Or maybe I'm not understanding your question.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Iceman7]

According to UCS-79 (75*Tnom/Rf)*(1-Rf/Ro)
Tnom= Noinal thickness
Rf=final mean radius
Ro=Original mean radius
The above equation is used to determine the %fibre elongation just tryin to figure out what values are to be considered for Ro and Rf...

 

[LittleInch]

Whatever they are (a google search identifies them quite well) they appear to have absolutely nothing to do with centre of gravity. if this was a new question then please start another post, but please do a search for UCS-79 on this site and others first.

It looks to me like a simple equation where the expansion of the element is measured by the initial radius compared to the new radius once it has been expanded?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[SnTMan]

Iceman7, a more proper reference would be UG-79. It is fairly well explained there. Ro = infinity, flat plate. Rf is knuckle radius for anything other than a hemi-head. Get it hot formed, you won't have to worry about it.

And it has nothing to do with CG.

Regards,

Mike



The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[racookpe1978]

Why the bloody Hades would I ignore the nozzles and manhole in calculating the center of gravity of the vessel? By the way, you forgot the two saddles in your CG "ignorance" request as well.

Who is your supervisor, and why are you asking an anonymous internet forum for design training on a project YOUR COMPANY becomes liable for when it fails?