## Need help with calculating the whole surface area of elements depicted on technical drawings

## Need help with calculating the whole surface area of elements depicted on technical drawings

(OP)

Hi!

Can someone please help me calculate the surface area of the below elements?

https://res.cloudinary.com/engineering-com/image/upload/v1706032543/tips/Nowy_obraz_mapy_bitowej_ygg7td.bmp

https://res.cloudinary.com/engineering-com/image/upload/v1706032660/tips/Nowy_obraz_mapy_bitowej_lc5ib8.bmp

https://res.cloudinary.com/engineering-com/image/upload/v1706032925/tips/Nowy_obraz_mapy_bitowej_ultwau.bmp

Can someone please help me calculate the surface area of the below elements?

https://res.cloudinary.com/engineering-com/image/upload/v1706032543/tips/Nowy_obraz_mapy_bitowej_ygg7td.bmp

https://res.cloudinary.com/engineering-com/image/upload/v1706032660/tips/Nowy_obraz_mapy_bitowej_lc5ib8.bmp

https://res.cloudinary.com/engineering-com/image/upload/v1706032925/tips/Nowy_obraz_mapy_bitowej_ultwau.bmp

## RE: Need help with calculating the whole surface area of elements depicted on technical drawings

Cheers

Greg Locock

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## RE: Need help with calculating the whole surface area of elements depicted on technical drawings

## RE: Need help with calculating the whole surface area of elements depicted on technical drawings

www.PeirceEngineering.com

## RE: Need help with calculating the whole surface area of elements depicted on technical drawings

To calculate surface area:

- Calculate perimeter using Section A-A.
- Find the radius R to the center of gravity of the perimeter.
- Multiply the perimeter from 1. by 2*pi*R.

Similarly, if you want to find the volume of material, find cross sectional area from Section A-A, calculate R', where R' is the radius to c.g. of area, then V = A*2pi*R'.## RE: Need help with calculating the whole surface area of elements depicted on technical drawings

Face ab is a circular ring with width (149.95-127.00)/2 = 11.475mm and an average diameter of (149.95+127.00)/2 or 138.475mm. It would have an area of 11.475*pi*138.475 = 4,992mm^2 if built precisely to the targeted dimension. But with an allowance of plus or minus 0.15mm in inside diameter, the width and diameter of the ring changes slightly.

Similarly, the other faces will have a targeted, minimum and maximum area which you should be able to calculate.

## RE: Need help with calculating the whole surface area of elements depicted on technical drawings

## RE: Need help with calculating the whole surface area of elements depicted on technical drawings