I need help in finding the surface area of a Archimedes screw.?

I need to calculate the material requirements for applying a protective coating to this screw conveyor. The length is 38'6", width of the conveyor is 3'6" and the torque tube is 2' in diameter. There are 20 flights in this conveyor from end to end with 2' of of tube on the top end to facilitate the turning motor. I need to separate the area for the flights and tube as they will get different materials. If anybody can help me I would appreciate it very much. I just do not know what kind of formula to use.

Answer:
I don't know the formula to find the actual area of a helical flight, but, while it wouldn't be mathematically exact, one could get a fair approximation by considering each flight as a disc with a hole in it, so the area would be outer radius² * π - inner radius² * π or about 6.5ft² for one side of one flight, for both sides of 20 flights, it would be about 260ft², this is a little lower than the actual area but might be a reasonable approximation, I think I'd round it up to 300 for estimating coatings.
The torque tube is just a cylinder, area = diameter * π * length (about 242 ft²)

If you need an exact answer, you could search for formulas for helicoids, one site I found has math over my head, but you could take a look: http://planetmath.org/encyclopedia/examp...

you need to put your question in the math department or google its really complicated whats me brudder inlaw says

To me seams like it would be faster just to draw it up in a cad program and use it's "surface area" tool :)

The answers post by the user, for information only, FunQA.com does not guarantee the right.

FunQA.com

I need help in finding the surface area of a Archimedes screw.?

Topic