Pipe Flow_Friction Factor Calculations_Pipe Diameter

From the article, "Pipe Flow/Friction Factor/Head Loss Calculations with Excel Spreadsheet Templates" (http://www.brighthub.com/engineering/civil/articles/84765.aspx), the pipe roughness for drawn brass or copper is 0.000005 ft. I would expect the value for SS 316L electropolished to be similar, but you may be able to find a better value somewhere. Once you have the roughness value, you can use the Excel template at "Excel Template for Pipe Flow/Head Loss Calculations" at http://www.brighthub.com/engineering/civil/media/p/84797.aspx, to make the friction factor and head loss calculations.

If you have 80 lb force pushing against the sphere, then you need slightly more than 80 lb pushing in the other direction to push the sphere back. The area of a 3/4 inch circle is (pi)*(3/4)^2/4 = 0.4418 sq in. For pressure P in the pipe, the force on the 3/4 inch circle closed by the sphere will be p*A = p*0.4418. If we set this equal to 80 lb, then p = 80/0.4418 = 181 psi. This is the pressure needed to balance the 80 lb force holding the sphere in place. Slightly more pressure will move the sphere.

If I had a 1inch diameter sphere blocking a 3/4 inch diameter hole at the end of a 3 inch diameter pipe with 80lbs of pressure, what would be the force pressure on the sphere. Would it be 80lbs? Does the shape of the object blocking the 3/4inch hole matter. I am wondering what amount of pressure would be needed to push that sphere back. Thank you for your help.

To determine SS 316L Electropolished piping friction head loss