Crane Test 6/29/2019 Flashcards
What are the two types of Wire Rope?
- Rotation Resistant
2. Non Rotation Resistant
What is Rotation Resistant?
non-rotating rope or non-spin
What is the safety factor in Rotation Resistant?
5:1 (unless lifting personnel 10:1)
What is the safety factor in Non-Rotation Resistant?
3.5:1 (unless lifting personnel 7:1)
How many wires should be broken in the CORE before removal of a ROTATION RESISTANT cable?
1 broken wire in core
How many wires should be broken, and within how many diameters, before removal of a ROTATION RESISTANT cable?
2 broken wires in 6 diameters
4 broken wires in 30 diameters
How many wires should be broken in the CORE before removal of a NON-ROTATION RESISTANT cable?
1 broken wire in the core
How many wires should be broken in a strand of 1 lay before removal of a NON-ROTATION RESISTANT cable?
3 broken wires in 1 strand of 1 lay
How many RANDOMLY DISTRIBUTED wires should be broken in 1 lay before removal of a NON-ROTATION RESISTANT cable?
6 randomly distributed broken wires in 1 lay
How many wires should be broken at the END CONNECTION before removal of a STANDING ROPE cable?
2 broken wires at the end connection
How many wires should be broken AWAY FROM the END CONNECTION before removal of a STANDING ROPE cable?
3 or more away from the end connections
What is eccentric reeving?
- hoist line not evenly distributed across sheaves
- creates side loading on boom or the block to hang uneven
What is excessive reeving?
- too many parts of line for the lift
- adds additional weight and the possibility to run out of rope
What is sufficient reeving?
-enough parts of line to make the lift?
What are the 3 Parts of Line?
- Eccentric Reeving
- Excessive Reeving
- Sufficient Reeving
What are some signs of unstable footing?
- uncompacted soil
- voids
- tanks
- plumbing
- loose backfill
When is unstable footing most common?
Most common around new construction
WHEN and WITH WHOM should you verify ground conditions?
Verify ground conditions WITH site supervisor AT new construction
What should be used to verify existing underground utilities and piping?
Verify with special number in phone book (LA One Call, Dottie), or local utilities for existing underground utilities and piping
What is the minimum swing clearance?
tail swing/superstructure radius plus 2’
What is the minimum excavation? Recommended?
1: 1 minimum
1. 5:1 recommended
What should you do if outriggers cannot be fully extended?
use next lower chart
- -if 50% chart is available, use it
- -if not, the on rubber chart may apply
What must blocking be able to support?
Blocking must be able to support the weight of the load and the crane
Where should the MOST ground bearing pressure be?
Most ground bearing pressure over corners
Where should the LEAST ground bearing pressure be?
Least ground bearing pressure on crawlers- over side
Which surface (hard or soft) has more ground bearing pressure?
HARD SURFACES have more ground bearing pressure than soft surfaces
Where must outrigger floats be attached?
Outrigger floats must be attached to STABILIZERS
What is the most common cause of crane turnover?
Unstable Footing
Where is the luffing jib controlled?
controlled from the cab
How does the luffing job move?
moves independently of the boom
In spooling, how many wraps minimum are required on the drum when hoisted down?
OSHA SAID THIS!!!
2 wraps minimum remaining on drum when hoisted down
What percentage should a crane be de-rated by?
Crane must be de-rated by 50%
What is required over land?
Fall Protection
What is required over water?
Life Jacket
How often are inspections required?
Daily
What percentage should a proof test be?
125%
When can the proof test and trail lift be done?
Proof test and trail lift can be done at the same time (concurrently, simultaneously)
B30.23
Personnel Platforms
B30.5
Mobile and Locomotive Crane Standard
B30.9
Slings
1910.180
Cranes in General Industry (mostly overhead cranes)
1926.1400
Cranes in Construction
1926.1431
Suspended Personnel Baskets
1926.1402
Ground Condition
1926.1412
Inspections
1926.1413
Wire Rope Inspections
1926.251
Rigging
1926.1407-1926.1411
Power Lines
What are the TWO most common causes of fatalities involving cranes?
- Use options or 20’ for under 350kv
2. Use options or 50’ for over 350kv
If voltage is known: OPERATING
10’ = ? kv
0-50kv
If voltage is known: OPERATING
15’ = ? kV
over 50-200 kV
If voltage is known: OPERATING
20’ = ? kV
over 200-350 kV
If voltage is known: OPERATING
25’ = ? kV
over 350-500 kV
If voltage is known: OPERATING
35’ = ? kV
over 500-750 kV
If voltage is known: OPERATING
45’ = ? kV
over 750-1000 kV
What is the minimum clearance required for crane setup?
minimum 20’ clearance
Transit:
4’ = ?
4’ = 0.75
Transit:
6’ = ? kv
over 0.75-50kv
Transit:
10’ - ? kv
over 50-345kv
What is the most common cause of a crane turnover?
unstable footing
What is the most common cause of crane operator fatalities?
crane turnover
What is the most common cause of crane operator injuries?
getting in and out of the cab
What is the most common cause of fatalities involving cranes?
electrocution
What happens within 1%?
Crane must be leveled
What happens at 20%?
Duty cycle reduction
What happens at 50%?
Personnel Basket- Crane de-rating
What is based on 75%?
Load charts based on 75% on rubber and crawlers (when not on outriggers)
What happens at 75%?
Multiple crane lifts - Reduce capacities
What is based on 85%?
Load charts based on 85% on outriggers
What happens at 100%?
Cranes capacity on properly blocked outriggers
What happens at 110%?
Load test to be performed no greater than 110% of capacity
What happens at 125%?
Proof test of personnel baskets
What is gross capacity?
total capacity of the crane as listed in load chart
What are deductions?
lifting devices that must be deducted from the gross
When should jib NOT be deducted?
Do NOT deduct jib if it is being used
When should jib be deducted?
If erected and not used, it MUST be deducted
What should be done if a jib is stowed?
If it is stowed, a stowed deduction must be made
What is a jib deduction based on?
effective weight of jib- not actual
What is net capacity?
gross capacity minus deductions
What is gross load?
total of everything lifted by crane (load, ABH, excess cable, block, ball, jib, rigging, etc.)
What is net load?
load only (pump, valve, pipe, etc. equipment being lifted)
What is a range diagram used for?
used to scale work
What is an area chart used for?
defines crane quadrants - front, side, back, 360 degrees, etc.
What is a necessity for mobile cranes on barges?
Mobile cranes on barges MUST have a list chart from the manufacturer
What is backward stability?
crane may turn over backward
How should you measure radius?
measure from center of rotation to center of gravity of a freely suspended load
When is the ONLY time side loading is allowed?
side loading only allowed with freely suspended load
What cranes are least stable over the side?
mobile cranes
When may truck cranes no have lifting capacities over the front?
if there is not a 5th outrigger
What is pick and carry?
over front, short boom, low angle, and as close as possible
Where is pick and carry with a truck crane?
over the rear
Where are rough terrain cranes more stable?
over the front
Where are truck cranes more stable?
over the rear
What is the jib offset based on?
Jib offset based on job angle in relation to the boom
What is the boom angle based on?
Boom angle based on boom angle in relation to horizontal
What percentage is Hook Throat Wear?
10%
What degree is a Hook Twist?
10 degrees
What percentage is a Hook Mouth Opening/Throat Opening?
15%
The ______ the sling angle, the _______ the tension exerted by the same weight.
The LOWER the sling angle, the GREATER the tension exerted by the same weight.
What is the jib capacity based on?
Jib capacity is based on the structure of the jib
What increases stability of a crawler?
Blocking under track tips
What happens during boom deflection?
load swings out as boom bends with a heavy load
above the line = ?
structure
below the line = ?
stability/tipping
When does wind affect a cranes capacity the most?
when it is from the side
What is a possibility if a telescopic boom that is designed to extend equally gets out of sequence?
it is possible to damage the section that extends too far
On a lattice boom crane with adjustable mast or gantry positions, when is the crane generally stronger?
when the mast or gantry is higher
When using a friction crane with ‘power down’ capabilities, how should you lower a heavy load?
always use the power down function to lower heavy loads; DO NOT rely on brakes.
When a mobile crane is placed on a barge, how is the list of vessel compensated for?
it must be secured and a “list” chart provided by the manufacturer must be used
When are frequent inspections held and by whom are they performed by?
- daily to monthly
- performed by COMPATENT person
When are periodic inspections held and by whom are they performed by?
- monthly to yearly
- performed by QUALIFIED person
When can J-Hooks be used?
when lifting trusses
What must jibs have to prevent them from rolling back?
positive stops