CDL Tank Cargo Surge

Question 1

A tank vehicle is carrying a partially filled load. What is "liquid surge"?

Accepted Answer

Movement of the liquid back and forth or side to side inside the tank

Answer

Liquid surge is the movement of liquid in a partly filled tank, forward and backward or side to side. It happens when the vehicle accelerates, brakes, or turns.

Question 2

Which tank design allows the most liquid surge?

Accepted Answer

A smooth-bore tank with no baffles

Answer

A smooth-bore tank has nothing inside to slow the liquid, so it allows the most severe surge. Baffles and bulkheads restrict movement.

Question 3

A baffled tank is partly full. Which statement about surge in it is correct?

Accepted Answer

Baffles help control front-to-back surge, but side-to-side surge can still occur

Answer

Baffles have holes in them and mainly slow forward-and-back surge. Side-to-side surge can still happen, and it can contribute to rollovers.

Question 4

What is the main reason a compartmented (bulkheaded) tank reduces surge?

Accepted Answer

Each compartment is a separate tank, so the liquid cannot surge along the whole length

Answer

Bulkheads divide the tank completely, so each compartment acts as a separate tank. Liquid can only surge within its own compartment.

Question 5

A driver brakes hard on a slippery road with a partly filled smooth-bore tank. What can happen as the vehicle slows?

Accepted Answer

The liquid surges forward and can push the vehicle ahead, increasing stopping distance

Answer

When you brake, the liquid moves forward and its momentum can push the vehicle ahead. On a slippery surface this can lengthen the stop.

CDL Tank Practice Test

CDL Tank Practice Test

CDL Tank Cargo Surge