Chapter 9

Question 1

Why are Snatch Blocks used?

Answer 1

To redirect a rope in may different rigging situations.

Question 2

When are Snatch Blocks commonly used?

Answer 2

When performing work on transmission lines.

Question 3

What can Snatch Blocks also reduce?

Answer 3

Haul Line Tensions in some rigging configurations.

Question 4

What is the unique feature of a Snatch Block?

Answer 4

It can open near the swivel to trap the bight of the rope

Question 5

What are the components that make up a Snatch Block?

Answer 5

• Hook
• Safety Latch
• Pivot Pin
• Locking Pin
• Shell
• Center Pin
• Sheave

Question 6

What should you do before using a Snatch Block?

Answer 6

Read the manufacturer’s recommended care and inspection criteria.

Question 7

When inspecting the Hook & Safety Latch what are you looking for?

Answer 7

• Bent Hook
• Defective Safety Latch
• Excessive wear at all contact points
• Metal Fatigue

Question 8

When inspecting the Locking Pin, Pivot Pin and Swivel what are you looking for?

Answer 8

• Metal Fatigue
• Rust
• Excessive Wear
• Operates Freely
• Lubricate if Needed

Question 9

When inspecting the Shell what are you looking for?

Answer 9

• Cracks
• Breaks
• Sharp Edges

Question 10

When inspecting the Center Pin what are you looking for?

Answer 10

Seated & Secured Tightly

Question 11

When inspecting the Sheave what are you looking for?

Answer 11

• Turns Freely
• Excessive wear on the bearings by moving the sheave up & down
• Cracks & Sharp Edges that can cut the rope

Question 12

Where will Snatch Blocks have their Weight Rating?

Answer 12

Stamped on the hook or shell

Question 13

What should you do with a Snatch Block if it doesn’t have a weight rating tag visible?

Answer 13

Remove it from service immediately.

Question 14

What should you always do before using blocks in a rigging application?

Answer 14

Read the weight rating and calculate the tensions involved.

Question 15

How should you store blocks?

Answer 15

In a dry place.

Question 16

What should you do if blocks become soiled?

Answer 16

Rinse thoroughly and lubricate the sheave bearing per the manufacturer’s recommendations.

Question 17

What is the tension placed on a Snatch Block dependent on?

Answer 17

The angle that the rope is passing through the block.

Question 18

What happens when the angle decreases?

Answer 18

The tension on the block increases.

Question 19

What does this tension affect?

Answer 19

Sling and point of attachment.

Question 20

What happens to the rope when it is passed through the block?

Answer 20

Friction is created.

Question 21

What is this amount of friction dependent on?

Answer 21

The angle that the rope passes through the block

Question 22

What is the standard amount of friction?

Answer 22

10%

Question 23

Where is the friction applied?

Answer 23

To the Line Out

Question 24

When the friction to the Line Out, how does it compare to the Line In?

Answer 24

Line out has 10% more than Line In

Question 25

What is the equation for Snatch Block Tension?

Answer 25

Snatch Block Tension = Line Out x Angle Factor

Question 26

Line Out of the first block is what to the second block?

Answer 26

Line In

Question 27

What does the tension of a block determine?

Answer 27

• Size of the Block
• Size of the Sling its attached to
• Size of the Anchor Point