Midterm Flashcards
Screw pin anchor shackle
Bell handles 2 connections
Pin handles 1 connection
Size up 1 from rope, if 1/8 wire rope, use 3/16 or 1/4 shackle
CM uses 5/8 shackle
Yield point
When an object bends outside it’s elastic range
What if risk?
Increase design factor to reflect the risk
Synthetic
3 strand
Kernmantle- climbing ropes with sheath
Double braids - sta-set braided rope covered with another braided rope
Eye bolts
We want forged shoulder eye bolts
Eye bolts used for straight pull
Fatigue
Repeated applying and removing of force on an object
Bending (flexure)
One area of beam is in compression; another part is in tension
Ultimate strength
The unit stress (strain) just before an object breaks
Hitch
Implies securing it to something
3 natural ropes and how good
Hemp is hemp
Manila is good
Sisal is crap
Shock load
1 cause of accidents with moving things
Rapid application of force to an object
rapid acceleration or deceleration
Knots reduce strength by
As much as 50%
Strength reduction factor
Factors that will decrease the strength of the materials
Knots in a rope
Type of termination on a wire rope
Knot
1 rope
Ac cable
7x19
7 bundles of 19 wires
Plow steel
Thimbles support sides
Don’t crimp middle last
Never less than 2 clips
Forces (4)
Compression
Tension
Shear
Torsional
Rigging is generally compressive
What is scope?
When you get a rigging assignment ask this.
What do we have to do?
When?
With who?
Working load limit
A percentage of the ultimate breaking strength
Allowable load limit
Allowable working load
Recommended working load
Safe working load
We size hardware according to this
Torsion
Twisting force
What is rigging?
Hanging something from something Scenery Speakers Truss Lights People
New rope SWL
5:1 with new rope
Smaller the diameter the higher the safety factor
Rope process
Organic fibers
Yarn
Strands
Bend
Implies two ropes
Trim chain
Grade 30 proof cool chain
