Tank Vehicles
Tank Vehicles tests liquid-load behavior, outage, baffles, and rollover prevention. Liquid movement changes braking and steering, especially in partly filled tanks.
Core rules
- Keep the center of gravity low and slow down before curves, ramps, and lane changes.
- Liquid surges forward on braking and sideways in turns. Baffles reduce but do not eliminate surge; bulkheads divide tanks into compartments.
- Leave outage space for expansion. Never fill a tank to the top; follow the tank's marked capacity and the product's expansion needs.
- Check hatches, valves, and emergency shutoffs. Make sure the tank is properly grounded or bonded when required.
- Smooth starts and stops reduce surge and improve control.
Worked example
A 6,000-gallon tank requires 2 percent outage. Two percent of 6,000 is 120 gallons. If the driver loads 5,950 gallons, only 50 gallons of expansion space remain, so the tank is overfilled for that rule. Reasoning: outage is calculated from tank capacity, not from the space left after loading.
Traps
Believing baffles make a tank behave like a solid load; filling until product escapes at the hatch; and entering a curve too fast because the tank is only partly full.