Pulling
Traditionally fibre optic cables were pulled through cable ducts in the same way as other cables, via a winch line. Every time a bend or undulation in the duct is passed the pulling force is multiplied by a friction dependent factor (which can be reduced by using lubricant). This means that the higher the local pulling force is, the higher the friction will be which the cable is experiencing while being pulled against the internal duct wall. This "capstan effect" leads to an exponential force build-up with pull distance, producing generally high pulling forces.
Read more about this topic: Cable Jetting
Famous quotes containing the word pulling:
“An amoeba is a formless thing which takes many shapes. It moves by thrusting out an arm, and flowing into the arm. It multiplies by pulling itself in two, without permanently diminishing the original. So with words. A meaning may develop on the periphery of the body of meanings associated with a word, and shortly this tentacle-meaning has grown to such proportions that it dwarfs all other meanings.”
—Charlton Laird (b. 1901)
“Our kids will develop a work ethic only if we require them to pay a portion of the cost of some of the things they want. They’ll learn to defer gratification the moment we stop routinely pulling out our wallets. And they’ll learn self-discipline only if we care enough to enforce reasonable limits.”
—Fred G. Gosman (20th century)
“As for conforming outwardly, and living your own life inwardly, I do not think much of that. Let not your right hand know what your left hand does in that line of business. It will prove a failure.... It is a greater strain than any soul can long endure. When you get God to pulling one way, and the devil the other, each having his feet well braced,—to say nothing of the conscience sawing transversely,—almost any timber will give way.”
—Henry David Thoreau (1817–1862)