Practice crane test Flashcards
What is the percent of capacity of a triple chain compared to two legs
150%
Defined the mechanical advantage of the block to the winch
Can multiply pulling power,
safe working load of cable increases equal to the parts added
What are the broken wire removal criteria for rotation resistant wire rope
Two random broken wires and six diameters or four randomly broken wires and 30 diameters
What is rope lay length
The length of the strand to make one full revolution around the wire rope
Define fleet angle
The angle drawn from the boom tip sheave to the ground and other line from the boom tip sheave to the center of the outer most flange of the boom hoist
1.5° smooth 2° grooved
What are the wear criteria for taking wire rope out of service
1/3 wear of the original outside dimension
Name four types of cranes
Rough terrain
All-terrain
Crawler mounted
Carrier mounted
Give two reasons why one Crane in a two crane pick would intentionally be given more weight
One crane has a higher capacity
Offset center of gravity
Give two causes of the majority of crane accidents
Wind, erratic swing, improper set up, human error
What type of bolt is used for angular lifts
Shoulder eyebolt
The rule of thumb is that all sheaves should have a D/d ratio of
20/1
What is overhaul weight
The weight needed to pull the line off the drum
What is the efficiency of a Flemish eye
90%
What is the termination efficiency of a wedge socket
80%
Being off level results in?
In accurate radius, invalid load chart, uncontrolled swinging, tipping
Wire rope sling capacities
Single leg___%?
Single choker___%?
Two leg vertical_____%?
Single leg 100%
Single choker 75%
To like vertical 200%
What is the minimum D/d ratio for boom hoist sheaves , boom tip sheaves, hoist block sheaves
Boom hoist sheaves 15/1
Boom tip sheaves 18/1
Hoist block sheaves16/1
Seven rejection criteria for chain slings
Heat damage, 5% stretch links, cuts, bent links, 10% wear, welded links, weld splatter. 4:1 safety factor
What is the allowable throat opening on a hook due to wear of original dimension?
5% 1/4”
ANSI B30.5 OSHA1926 sub part cc
Safety and health regulations for cranes in derricks in construction
List five things to look for when inspecting wire rope
Broken wires, kinks, core Protrusion, corrosion, bird caging, Electrical contact
What are the broken wire removal criteria for wire rope terminations?
One broken wire at the end fitting, no more than two broken wires beyond the end fitting
What’s three basic functions of blocks
Increase permissible line pull, change of direction, change of speed
What are four causes of bird caging
Pulling through tight sheaves, shock loading, sudden stops, rope wound to tight on drum
