CDL Tanker Practice Test 2 — Questions and Answers
Question 1: Why are specials skills and knowledge required to drive a tanker?
- Tankers have a high center of gravity
- Tankers have an increased risk of rollover
- Liquid surge can occur in tankers
- All of the above (Correct answer)
Correct answer: All of the above
Driving a tanker requires special skills and knowledge due to several unique characteristics. Tankers have a high center of gravity, making them more prone to rollovers. Additionally, the phenomenon of liquid surge, where the cargo sloshes inside, can destabilize the vehicle. These combined factors necessitate specific driving techniques and heightened awareness to operate safely.
Question 2: Dividers inside tankers that have holes in them are known as what?
- Barriers
- Bulkheads
- Baffles (Correct answer)
- Separators
Correct answer: Baffles
Baffles are partial dividers with holes inside tanker trucks, designed to reduce the sloshing motion of liquid cargo. Their primary purpose is to control forward-and-back surge, which helps stabilize the vehicle. Unlike bulkheads, baffles allow liquid to pass through, dampening movement without fully compartmentalizing the tank.
Question 3: Why are baffles used in some tankers?
- To make the interior of a tanker easier to clean out
- To control forward-and-back liquid surge (Correct answer)
- To eliminate side-to-side liquid surge
- To allow you the hauling of mixed loads
Correct answer: To control forward-and-back liquid surge
Baffles are used in tankers to control the significant forward-and-back liquid surge that occurs during acceleration and braking. This sloshing motion, if unchecked, can destabilize the vehicle and make it difficult to control. By dampening the liquid's movement, baffles improve vehicle stability and safety.
Question 4: Why should you have sufficient outage in a tanker truck?
- To reduce the possibility of liquid surge
- To lower the center of gravity of the tanker
- To reduce the chance of leaks due to liquid expansion (Correct answer)
- To reduce the weight of the tanker
Correct answer: To reduce the chance of leaks due to liquid expansion
Sufficient outage refers to the empty space left at the top of a tanker's compartment after loading liquid cargo. This space is crucial because liquids expand when they get warm. Without adequate outage, the expanding liquid could build up dangerous pressure, potentially causing the tank to rupture or leak, creating a serious hazard.
Question 5: How should you drive on curves with a tanker vehicle?
- Drive at the posted speed on the curve
- Slow down before the curve, then accelerate through the curve (Correct answer)
- Accelerate before the curve, then downshift as you go through the curve
- Use controlled braking as you go through the curve
Correct answer: Slow down before the curve, then accelerate through the curve
When driving a tanker vehicle on curves, it is essential to slow down significantly before entering the curve. This reduces the centrifugal force acting on the high center of gravity of the liquid cargo, which can cause instability. Accelerating gently through the curve helps maintain vehicle stability and traction, preventing dangerous liquid surge and potential rollover.
Question 6: Why do you need to know the outage requirements when hauling liquids in bulk?
- Outage requirements vary across liquids (Correct answer)
- Some baffled tankers do not require outage
- Some heavy liquids do not require outage
- All of the above
Correct answer: Outage requirements vary across liquids
Outage requirements vary across different liquids because each liquid has a unique rate of thermal expansion. Some liquids expand more than others when heated, requiring more empty space in the tank to prevent over-pressurization. Knowing these specific requirements is crucial for safe transport and to prevent leaks or tank damage.
Question 7: In which direction do baffled tanks NOT usually prevent the movement of surge?
- Up and down
- Side to side (Correct answer)
- Forward and backward
- All of the above
Correct answer: Side to side
While baffles are effective at controlling forward-and-back liquid surge, they do not typically prevent side-to-side movement of the liquid. Because baffles have holes, liquid can still slosh from one side of the tank to the other. This side-to-side surge can be particularly dangerous on curves, increasing the risk of a rollover.
Question 8: How does a baffled tanker handle differently than a tanker with baffles?
- The baffled tanker will have less side to side surge than the unbaffled tanker
- The baffled tanker can handle curves faster than an unbaffled tanker
- The baffled tanker will have less front to back surge than the unbaffled tanker (Correct answer)
- The baffled tanker will handle the same as the unbaffled tanker
Correct answer: The baffled tanker will have less front to back surge than the unbaffled tanker
A baffled tanker handles differently than an unbaffled tanker primarily because the baffles significantly reduce front-to-back liquid surge. This dampens the sloshing motion of the cargo during acceleration and braking, leading to improved vehicle stability and control. Consequently, the driver experiences less dynamic weight shift, making the vehicle safer and easier to manage.
Question 9: Which of the following is a potential danger of side to side surge?
- Containment breach
- Rollover (Correct answer)
- Suspension system failure
- None of the above
Correct answer: Rollover
Side-to-side surge, or sloshing, occurs when liquid cargo moves from one side of the tank to the other, especially during turns or sudden maneuvers. This shifting weight creates a dynamic force that can drastically alter the vehicle's center of gravity. This instability significantly increases the risk of a rollover, which is a major safety hazard for tanker trucks.
Question 10: Which of the following is a liquid tight divider between compartments inside of a tank?
- Bulkhead (Correct answer)
- Baffle
- Separation walls
- None of the above
Correct answer: Bulkhead
A bulkhead is a solid, liquid-tight divider that completely separates compartments inside a tank. Unlike baffles, which have holes to dampen surge, bulkheads prevent liquid from moving between sections. This allows for hauling different types of cargo or partial loads without mixing, and it also helps manage surge by creating smaller, independent liquid volumes.
CDL Tanker Practice Test 2
Why are specials skills and knowledge required to drive a tanker?