Pipefitter Rigging and Hoisting Operations 5 — Questions and Answers
Question 1: When using a below-the-hook lifting device such as a pipe lifting beam, what document must be available on site during the lift?
- The crane operator's license
- The manufacturer's load rating chart and instructions (Correct answer)
- The foreman's rigging certification
- The site safety plan only
Correct answer: The manufacturer's load rating chart and instructions
ASME B30.20 requires that the manufacturer's load rating chart and operating instructions be available for below-the-hook lifting devices.
Question 2: A pipefitter needs to rig a 10,000 lb pipe section using a basket hitch. If the sling angle (from horizontal) is 45 degrees, what is the approximate tension in each sling leg?
- 3,536 lb
- 5,000 lb
- 7,071 lb (Correct answer)
- 10,000 lb
Correct answer: 7,071 lb
At 45 degrees from horizontal, each leg tension = (load/2) ÷ sin(45°) = 5,000 ÷ 0.707 ≈ 7,071 lb.
Question 3: What is the primary purpose of a swivel hoist ring compared to a standard eyebolt for rigging?
- It provides a higher working load limit in all directions
- It allows 360-degree rotation and angular loading without reducing rated capacity (Correct answer)
- It is lighter weight for easier handling
- It is designed exclusively for vertical lifts
Correct answer: It allows 360-degree rotation and angular loading without reducing rated capacity
Swivel hoist rings rotate 360 degrees and pivot to accommodate angular loading without the capacity derating required for standard eyebolts.
Question 4: During a critical pipe lift, the rigger notices the crane load line is not plumb over the load's center of gravity. What is the correct action?
- Proceed slowly and compensate with tag lines
- Reposition the crane or adjust rigging until the load line is plumb (Correct answer)
- Add counterweights to the light side of the load
- Signal the operator to lift quickly before the load can swing
Correct answer: Reposition the crane or adjust rigging until the load line is plumb
The load line must be plumb over the center of gravity before lifting to prevent uncontrolled swinging or side loading the crane.
Question 5: What is the function of a load moment indicator (LMI) on a mobile crane?
- It measures the weight of the slings and rigging hardware
- It monitors boom angle, radius, and load to warn of approaching the crane's capacity (Correct answer)
- It controls the speed of the hoist drum automatically
- It calculates the center of gravity of the suspended load
Correct answer: It monitors boom angle, radius, and load to warn of approaching the crane's capacity
An LMI continuously monitors boom angle, radius, and load weight to provide warnings before the crane's rated capacity is exceeded.
Question 6: Which OSHA standard primarily governs rigging equipment used for material handling in general industry?
- 29 CFR 1910.179
- 29 CFR 1926.502
- 29 CFR 1910.184 (Correct answer)
- 29 CFR 1926.1437
Correct answer: 29 CFR 1910.184
29 CFR 1910.184 is the OSHA standard that governs slings used in hoisting operations in general industry settings.
Question 7: When inspecting a synthetic web sling before use, which defect is an immediate disqualifier?
- Slight stiffness from cold temperatures
- Minor surface abrasion affecting less than 10% of sling width
- Any acid or caustic burns (Correct answer)
- Fading of the label color from UV exposure
Correct answer: Any acid or caustic burns
Any acid or caustic burns on a synthetic web sling require immediate removal from service as chemical damage compromises the entire sling.
Pipefitter Rigging and Hoisting Operations 5
When using a below-the-hook lifting device such as a pipe lifting beam, what document must be available on site during the lift?