## Calculations

**Tubing Weight Per Foot** is calculated by taking the O.D. and subtracting the wall thickness. This figure is then multiplied by the wall thickness with that result again multiplied by 10.68 to determine the tube weight per foot. Example: 2" O.D. tube with a 1/4" (0.250") wall. Start with 2.000 minus .250, then multiply by .250, then multiply again by 10.68. The result should be 4.6725 pounds per foot.

**Millimeters to Inches** is determined by multiplying the MM diameter by .03937" Example: 12mm. Start with 12 and multiply by .03937". The result is 0.4724" which is the conversion from metric to standard U.S. measurement.

**Kilograms to Pounds** can be determined by multiplying the kilograms by the number 2.2046. Example: 5 kilogram. Multiply 5 by 2.2046. The result is 11.023 pounds.

**Metric Tonnes to U.S. Tons** can be determined by multiplying the metric tonnes by 1.1023. Example: 4 metric tonnes. Multiply 4 by 1.1023. The result is 4.4092 U.S. tons, or 8,818.4 pounds.

**Barlow's Theoretical Bursting and Bulging Pressure for Tubing** is for theoretical bursting pressures, use tensile values; for theoretical bulging pressures, use yield values. The formula is P = 2ST/D where P = Internal Pressure in PSI; S = fiber stress of tube in PSI; T = wall thickness in inches; and D = Outside diameter in inches.