 # Formulas

## SHAPE WEIGHT FORMULAS

The following shape formulas can be used to calculate the nominal weights for various carbon steel shapes. These weight calculations are based upon the theoretical weight of steel at 40.80 pounds per square foot per one inch of thickness. These weight formulas are for nominal weights, (and are approximations), and should not be considered an exact weight. All dimensions are to be in inches.

 Rounds = Diameter squared x 2.67 = Weight in pounds per Linear Foot. Squares = Diameter squared x 3.4 = Weight in pounds per Linear Foot. Hexagons* = Diameter squared x 2.945 = Weight in pounds per Linear Foot. Octagons* = Diameter squared x 2.817 = Weight in pounds per Linear Foot. Plates, Sheets & Flats = Thickness x Width x 3.45 = Weight in pounds per Linear Foot. Plate Circles = Diameter squared x thickness x .2225 = Weight per Circle. Round Tubing = 10.68 x (O.D. – W.T.) x W.T. Square Tubing = 13.6 x (O.D. – W.T.) x W.T. Rectangular Tubing = 13.6 x [(SL + SS) – W.T.] x W.T. * Diameter is measured across the flats.O.D. = Outside Diameter W.T. = Wall Thickness SL = Long Side SS = Short Side

## GENERAL FORMULAS

 Cost per Hundred Feet = Cost per Hundred Weight x Weight per Foot. Cost per Hundred Weight = Cost per Hundred Feet / Weight per Foot. Area of a Circle = Diameter x Diameter x 0.7854 Circumference of a Circle = Diameter x 3.1416 Diameter of a Circle = Circumference x 0.31831 Area of a Triangle = Base x Perpendicular Height x 0.5 Area of a Rectangle = Width x Length Area of a Square = Side x Side Area of Parallelogram = Base x Altitude Side of an Inscribed Equal Square for a Circle = Diameter x 0.8862 Side of a Square x 1.4142 = Diameter of Circumscribed Circle Doubling the Diameter of a Circle increases the area of the Circle four times. Doubling the diameter of a Pipe increases its capacity four times.

## METRIC CONVERSION FORMULAS

 Millimeters x .03937 = Inches Inches x 25.40 = Millimeters Meters x 3.2809 = Feet Feet x .3048 = Meters Kilometers x .621377 = Miles Miles x 1.6093 = Kilometers Liters x 61.023 = Cubic Inches Cubic Inches x .01639 = Liters Liters x .26418 = U.S. Gallons U.S. Gallons x 3.7854 = Liters Grams x .03527 = Ounces Ounces x 28.350 = Grams Metric Ton x .9072 = U.S. Ton U.S. Ton x 1.1023 = Metric Ton Metric Ton = 2205#