Crane Refresher Practice Test

Question 1

List for criteria that make a critical lift

Answer 1

75% of rated capacity, personnel hoisting, special rigging procedures, two or more cranes (or hooks)used to make a lift

Question 2

What prevents the boom from falling when a hydraulic line fails 

Answer 2

Positive pressure holding valve/ check valves on the cylinder

Question 3

What are the wear criteria for taking a hook out of service?

Answer 3

More than 5% wear in critical areas, 10% in other areas, no more than 1/4” inch at throat opening

Question 4

What is fleet angle?

Answer 4

The maximum angle made by a rope with a line perpendicular with the drum on a crane. It would be centerline of points to the drum flange farthest from the perpendicular centerline. 1.5 degree smooth 2 degree grooved max

Question 5

Describe how to make a turn back eye with wire rope clips

Answer 5

Measure the dead end length, fasten first clip furthest from eye, 1 saddle width in from the end of tail, be sure to install all clips with saddle on the live end, install second clip closest to eye, with thimble placed in eye, install remaining clips evenly spaced between the 1st and 2nd, torque to manufacturers specification, then re-torque a second time. Never saddle a dead horse

Question 6

What is PLP?

Answer 6

Permissible Line Pull. The rated pull capacity of a winch ( allowable in pounds)

Question 7

Explain D/d ratio

Answer 7

The diameter of the wire rope compared to the diameter of the object it goes around

“D” divided by “d” = D:d ratio

Question 8

What is the D/d ratio for different types of sheaves?

Answer 8

Block sheave 16:1
Boom point sheave 18:1
Boom hoist sheave15:1

Question 9

How are parts of line determined?

Answer 9

Suspended load divided by Safe Working Load SWL or PLP Permissible line pull 

Question 10

What class is 6x25 wire rope?

Answer 10

6x19 (6 strand 15-26 wires, 6x7 6x37 8x19)

Question 11

What is cabling?

Answer 11

When a multipart hoist spins/twists enough that different parts of line make contact

Question 12

What will reduce cabling?

Answer 12

Switch to even parts of line, reduce length of the fall, use rotation resistant rope, reeve fall symmetrically, change sheave size

Question 13

How far out of level may a crane be before the load chart is not valid?

Answer 13

1%

Question 14

Short sections of boom go towards______

Answer 14

The boom base section

Question 15

Broken wire out of service criteria, rotation resistant rope.

Answer 15

2 wires in 6 diameters or 4 in 30 diameters. Personnel lifts add 1 valley break

Question 16

wire rope sling broken wire criteria

Answer 16

5 broken wires in one strand in one lay , or 10 or more broken random broken wires in one lay

Question 17

Broken wire for running ropes

Answer 17

3 broken wires in one strand in one lay or 6 random broken wires in one lay

Question 18

Crane hook closest to the center of gravity picks _____ weight.

Answer 18

More

Question 19

If a two crane pick is not made evenly, more load shifts to the upper or lower hook?

Answer 19

The lower hook

Question 20

Why would you want one crane to get more of the load in a two crane pick?

Answer 20

Offset C/G, odd sized or shaped load, different load capacities

Question 21

Wear criteria for taking wire rope out of service.

Answer 21

Reduction in diameter of 1/3 of the outside wires original diameter

Question 22

Safety factor for running rope

Answer 22

Working 3.5:1
Erecting 3.0:1

Question 23

Safety factor for standing wire rope

Answer 23

3.0:1 working
2.5:1 erecting
Tower crane 5:1

Question 24

Safety factor for rotation resistant wire rope

Answer 24

5:1
10:1 for personnel lifting

Question 25

Reasons for taking wire rope out of service, other than wear and broken wires

Answer 25

Heat damage, corrosion, birdcaging, core protrusions, distortion, high stranding, dog legs, crushing, kinks

Question 26

What information is obtained from a load chart?

Answer 26

Gross capacity, boom length/angle/radius, deductions, warnings, operational notes, configurations

Question 27

List 7 reasons for backward tipping

Answer 27

Improper set up, severe unloading, two blocking, rigging failure, erratic swinging, traveling uphill with too high a boom angle, operator error, wind

Question 28

List the three types of shackles

Answer 28

Pin Screw Bolt

Question 29

Symmetrical reeving of fall block is best, avoids torsion loading of boom tip

Question 30

What is recommended for blocking (cribbing) off outrigger pads 

Answer 30

3 times the size of outrigger pad surface area, tight together and parallel

Question 31

What is the minimum allowable amount of wraps on a hoist/boom drum?

Answer 31

2 wraps minimum

Question 32

What is duty cycle?

Answer 32

Repetitive motion operation, for example digging, concrete, bucket, steel erection

Question 33

What is the chart reduction for duty cycle

Answer 33

20%

Question 34

What are the weights for these items per cubic foot in pounds? Water Steel Concrete

Answer 34

Water 62 pounds per cubic foot Steel, 490 pounds per cubic foot Concrete150 pounds per cubic foot

Question 35

What is the efficiency of a Flemish eye

Answer 35

90%

Question 36

What is the efficiency of a wedge socket? (Becket)

Answer 36

80%

Question 37

What is the efficiency of wire rope clips

Answer 37

80% under 1 inch diameter 90% 1 inch and above

Question 38

What is the efficiency of a spelter socket?

Answer 38

100%

Question 39

What is the efficiency of a swaged fitting?

Answer 39

100%

Question 40

What should a tail length be on a wedge socket with regular rope? 

Answer 40

Six diameters of the wire rope, but never less than 6 inches

Question 41

What should the tail length to be on a wedge socket with rotation resistant wire rope?

Answer 41

20 diameters of the wire rope, and no less than 6 inches

Question 42

What makes wire rope more flexible

Answer 42

More wires equals more flex or softer core construction

Question 43

Maximum allowable throat opening for a hook

Answer 43

5% of the original dimensions, but no more than a quarter of an inch

Question 44

Other types of wire rope core besides IWRC

Answer 44

Fiber and synthetic

Question 45

Triple leg slings have 50% more capacity than double leg slings. Only if the center of gravity is in center of the connection point and legs are adjusted to equally share the load. Quad leg slings offer improved stability but do not provide increased lifting capacity.

Question 46

Only use drop forged wire, rope clips

Question 47

What is the criteria when measuring wire rope?

Answer 47

Measure crown to crown, 3 times for 6 strand wire and 4 times for 8 strand wire

Question 48

How is safe working load (SWL) determined

Answer 48

Ultimate breaking strength divided by the safety factor

Question 49

Two categories of weight chart

Answer 49

Stability, and structural

Question 50

How far back from a hole 10 feet deep is recommended

Answer 50

1 to 1 plus 2’ for the berm = 12’ 10” plus 2” for the berm= 12”

Question 51

Sorting hooks should be used at an angle less than___degrees

Answer 51

45°

Question 52

A 7 1/2 ton sorting hook tip loaded it will only be good for about two tones 

Question 53

Out of service speeds for wind

Answer 53

20MPH when lifting personnel 30MPH

Question 54

Load angle factors 90° 60° 50° 45° 30° 

Answer 54

90° 1.0 60°, 1.155 50°, 1.305 45°, 1.414 30° 2.0