Rigging Flashcards
What are two fibers used in natural rope construction?
Manila, which is strong and durable and
Sisal, which is less durable and lower in strength.
Synthetic ropes are less susceptible to ______ and _____?
Mildew and rot
Nylon, Terylene, Dacron, and Polypropylene are the most common materials for what?
Synthetic Ropes
General construction of rope consist of three ______which are then made up of multiple _______?
Strands, threads
Rope itself is twisted in a _______ hand direction. Each strand is twisted in a _____ hand direction. And the individual threads wound in a _____ hand direction.
Right, Left, Right.
How does one go about cleaning rope?
Rinse with water and hang in loose folds so that air can circulate freely around the rope.
If rope becomes stiff and hard, ______ or ______ can be applied to make it pliable again.
Lubricating Oil, Warm Petrolatum
What do you do to prevent rope ends from fraying or beginning to unravel?
Bound or whipped
Whippings are usually made with strong _____ and length should ____ to the diameter of the rope in which it is used.
Twine, equal
Chains should be removed from service if they show what percentage of wear?
10%
What does S, D, T and Q mean when ordering chain slings?
Single, double, triple or quadruple legs.
Water weighs approximately ____ lbs per gallon?
8.33
How much does a gallon of gasoline weigh?
5.84 lbs
Describe WLL
Working Load Limit, is a term used to describe the capacity of individual rigging components. It is the maximum load which can be applied and never to be exceeded.
What is safety factor?
A safety or design factor which refers to the reserve capability of a component calculated by dividing the breaking strength by the WLL.
Is the safety factor higher or lower when the rigging in question is utilized to suspend people?
Higher
Two types of rope construction include?
Twisted and Braided
Explain the rule of thumb for the WLL of rope.
Change rope diameter to 1/8’s square the numerator then multiply by applicable constant.
40 three strand polypropylene
50 hollow braid polypropylene
50 polydacon
70 three strand nylon
90 double braid nylon
If a slings WLL is _____ the weight of the pick, sling angles can be ignored.
Doubled
Sling angles should be kept above __ degrees to prevent excessive weight on each leg.
30 degrees
What is the equation for calculating load on a down guy?
Guy tension = line tension X length of guy (hypotenuse) ÷ distance to the anchor.
How do you calculate conductor weight in span?
Conductor weight lbs/ft X (1/2 span A + 1/2 span B)
What are three types of wire tongs saddles used in hot sticking?
Pole, crossarm and tower.
