Page 26 - Pipeline Rules of Thumb Handbook

General Information 13

Estimate the horsepower that can be transmitted by a shaft

3
1. Where there are no stresses due to bending, weight of DN
HP =
the shaft, pulleys, gears, or sprockets, use: 125
3
DN Example. What horsepower can be transmitted to an
HP = atmospheric cooling coil by a two-inch shaft turning at 1,800
50
revolutions per minute?
where D = diameter of shaft, in. 3
2
N = revolutions per minute HP = () (1 800, )
125
2. For heavy duty service use: = 115.2 horespower

MISCELLANEOUS

How to estimate length of material contained in roll

Where material of uniform thickness, like belting, is in a Example. A roll of belting contains 24 turns. The diame-
roll, the total length may be obtained by the following ter of the hole is two inches, and of the outside of the roll is
rule: 13 inches.
Measure the diameter of the hole in the center, and of (
.
.
+
the outside of the roll, both measurements in inches; count 2 13) ¥ 24 ¥ 0 13 = 46 8
the number of turns; multiply the sum of the two measured The roll contains 46.8 feet of belting.
diameters by the number of turns, and multiply this prod- Note: The rule can even be applied to materials as thin as
uct by 0.13; the result is the total length of the material in pipeline felt; counting the turns is not as difficult as might
feet. appear without a trial.

Convenient anti-freeze chart for winterizing cooling systems