Reference Formulas

To find wall: O.D. - I.D. ÷ 2 = Wall

To find O.D.: I.D. + (2 x wall) = O.D.

To find I.D.: O.D. - (2 x wall) = I.D.

To find weight per foot of round steel tubing: (O.D. - wall) x wall x 10.68 = WPF

To find weight per foot of round steel bar: Dia. x Dia. x 2.67 = WPF


To find the estimated bursting pressure of tubing, using the Barlow formula:

P = 2StD

P = Pressure

S = Allowable stress

t = Wall thickness

D = Outside diameter

To the top