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Square inches to diameter

Wed Aug 31, 2011 7:31 am

I need to know the equation(and answer) of turning square inches to the OD of a pipe. It is 1.79 Sq.In. Thanks you.

Re: Square inches to diameter

Wed Aug 31, 2011 10:45 am

Neonnblack wrote:I need to know the equation(and answer) of turning square inches to the OD of a pipe. It is 1.79 Sq.In. Thanks you.

The area of a circle is pi * R^2, where pi = 3.14159 and R is the radius of the circle.

Thus, knowing the area, we can calculate the radius: R = square root of ( area / pi ). In your case R = sqrt( 1.79 / 3.14 ) = 0.755 in. And then Diameter = 2*R = 2*0.755 = 1.51 in.

Please note - in real life the pipe wall has some nonzero thickness, so inner and outer diameters of the pipe are different. If your figure 1.79 sq.in. is the area of the pipe including the pipe wall, then the formula above will give you the outer diameter (OD) of the pipe. If you figure is the area inside of the pipe (excluding the wall), then the calculation gives you the inner diameter.

More info

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