Lesson 10 Flashcards
Use and Operation of Blocks (24 cards)
In both figures, the tension on the line is 500 pounds. The hook load for the setup in Figure A is 1,000 pounds. The hook load for Figure B is ? .
a. less than 1,000 lbs
b. 1,500 lbs or more
c. exactly 1,700 lbs
d. 2,000 lbs or more
a. less than 1,000 lbs
The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Pg. 681, “The Strain on a Block and Anchor Point,” Formulas, and Pg. 682, Figure 17-22
In the picture, the mechanical advantage is ? .
a. 1
b. 2
c. 3
d. 4
a. 1
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 184, Figure 7-25
The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Chap. 17, Pg. 690, Figure 17-34
In the picture, the mechanical advantage is ? .
b. 2
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 184, Figure 7-25
The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Chap. 17, Pg. 690, Figure 17-34
In the picture, the mechanical advantage is ? .
a. 1
b. 2
c. 3
d. 4
c. 3
The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Chap. 17, Pg. 690, Figure 17-34
The constant force applied to an object to keep that object in place is ? force.
a. friction
b. lifting
c. sheer
d. static
d. static
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 184, “Static Forces,” Paragraph 1, Sentence 2
As a rule of thumb, the friction loss for each sheave is approximately ? of the sheave load.
a. 5%
b. 10%
c. 15%
d. 20%
b. 10%
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 186, Figure 7-27, Note
As the angle between the load line and the lead line (fall line) increases, the load of the block ? .
a. decreases
b. does not depend on the angle of the lines
c. increases
d. stays the same
a. decreases
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 192, Paragraph 1, Sentence 1, and Pg. 193, Figure 7-36
A ? block is the lower movable block in a block and tackle configuration.
a. gin
b. standing
c. tackle
d. traveling
d. traveling
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 182, Paragraph 6, Sentence 4
A single block hoisting assembly has a fall line pull of 150 pounds. If the lines are parallel to each other and ignoring friction, the load on the block will be ? .
a. 75 lbs
b. 150 lbs
c. 300 lbs
d. 450 lbs
c. 300 lbs
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 192, Figure 7-35, and Pg. 193, Figure 7-36
The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Pg. 682, Figure 17-22
A single block hoisting assembly has a lead line pull of 1,500 pounds. If the lines are perpendicular to each other and friction is ignored, the load on the block is ? .
a. half as much as the load (750 lbs)
b. the same as the load (1,500 lbs)
c. more than the load by about half (2,121 lbs)
d. twice as much as the load (3,000 lbs)
c. more than the load by about half (2,121 lbs)
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 193, Figure 7-36 and Formula, and Pg. 192, Formula
The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Chap. 17, Pg. 681, “A Rule of Thumb,” and Pg. 682, Figure 17-22
Using an improperly sized block can derate the Working Load Limit of the wire or fiber rope that is used with it.
True or False?
True
The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Chap. 17, Pg.681, “Matching Rope Blocks and Rope Size,” Paragraph 1, Sentence 1
As more sheaves reduce the force required to lift a load, the distance the lead line must be pulled decreases.
True or False?
False
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 187, “Travel Distance,” Paragraph 1, Sentence 2
The force of two objects resisting movement is ? .
a. compression
b. friction
c. tension
d. torque
b. friction
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 179, Paragraph 1, Sentence 2
Mechanical advantage means that a load can be lifted by applying a force more than the load weight.
True or False?
False
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 183, Paragraph 1, Sentence 1
A sheave is a grooved wheel attached to a frame that supports a rope that is changing directions.
True or False?
True
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 180, “Blocks,” Paragraph 1, Sentence 2
Before a new wire rope is threaded over a block sheave, a Qualified Electrical Worker should check ? .
a. that the contour of the sheave matches the rope size
b. the condition of any splices on the wire rope
c. the length of the supporting sling and the size of the block hook
d. the type of eye on the end of the wire rope
a. that the contour of the sheave matches the rope size
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 194, “Block Inspection,” Paragraph 1, Sentence 1
The lead line is the part of the rope to which force is applied to hold or move a load.
True or False?
True
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 182, “Tackle,” Paragraph 3, Sentence 2
When lifting a load with a block and tackle system, part of the lifting force is lost due to ? in the turning of the sheaves.
a. compression
b. friction
c. heat
d. tension
b. tension
Lineworker Rigging Practices Textbook, Pg.185, “Lifting Forces,” Paragraphs 1-2
Lacing is the simplest method of reeving.
True or False?
True
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 189, Paragraph 1, Sentence 1, Under Figure 7-31
A nylon rope cannot be used with a snatch block.
True or False?
False
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 182, Paragraph 3, Sentence 3
The working load limit is determined by the breaking strength of rigging equipment, divided by the ? .
a. maximum breaking limit
b. maximum load limit
c. overload limit
d. safety factor
d. safety factor
Lineworker Rigging Practices Textbook, Chap. 7, Pg. 180, “Working Load Limits,” Paragraph 1, Sentence 1
The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Chap. 17, Pg. 663, Paragraph 2, Sentence 2
In the picture, the mechanical advantage ratio is 4:1.
True or False?
True
Lineworker Rigging Practices Textbook, Pg. 189, Figure 7-31
The Guidebook for Linemen and Cablemen 2nd Ed. Textbook, Chap. 17, Pg. 690, Figure 17-34
A crew has a job assignment to hoist a 3,200-pound bundled conductor in order to change out a string of insulators. The crew will use a four-part block and tackle system to accomplish this task. The sheave is a roller bearing type, with only 10% loss due to friction, threaded with 1/4-inch wire rope. The lead or fall line is threaded through the stationary or top block of the system.
The lead line tension needed to lift the conductor bundle with the block friction figured in would be ? .
a. 980 lbs
b. 1,120 lbs
c. 1,790 lbs
d. 1,990 lbs
b. 1,120 lbs
Lineworker Rigging Practices, Chap. 7, Pg. 185, Paragraph 1, Formula, and Pgs. 186-187, Formulas
Using the image of a hand-line block, identify the labeled parts.
Parts include: Locking Device, Pin, Swivel, Hook, Sheave, Shell
Number 1: Hook
Number 2: Swivel
Number 3: Sheave
Number 4: Locking Device
Number 5 Shell
Number 6: Pin
Reference: Hand-line Block, Figure
