Dock Leveler

A dock leveler is a hinged steel platform recessed into the pit of a loading dock. Trucks back up to the dock face, and because no two trucks have identical bed heights, a fixed dock edge cannot reliably meet them. The dock leveler solves this by raising and lowering a deck plate and extending a pivoting lip onto the trailer floor. The result is a continuous ramp between the warehouse and the trailer that forklifts and pallet jacks can cross safely.

The device has two main parts: the deck (the main platform) and the lip (a hinged extension that reaches onto the truck). When not in use, the deck sits flush with the warehouse floor and the lip hangs vertically. When a truck arrives, the operator activates the leveler, the deck rises above the trailer height, the lip pivots out and rests on the trailer bed, and then the deck lowers until the lip supports the load on the trailer.

Common types:

• Mechanical - A pull-chain raises the deck; the installer releases it to fall onto the trailer. Low cost, suitable for light-duty use.
• Hydraulic - A push button extends hydraulic cylinders to raise the deck and swing the lip. Faster and easier than mechanical; the standard choice for high-volume docks.
• Edge-of-dock (EOD) - A smaller unit that mounts on the dock face rather than in a pit. Works where a pit cannot be cut.
• Vertical-storing - The deck stores upright overnight, allowing the dock door to close tightly behind it for better temperature and pest control.

Dock levelers are specified by deck capacity (typically 25,000 to 80,000 pounds), deck width (matching the door opening, commonly 6 or 7 feet), and working range (how far up and down the deck travels, typically plus 6 to minus 12 inches from dock height).

The dock leveler works alongside the dock door above it. In most installations, the door must be fully open before the leveler activates, and some modern controls interlock the two to prevent the door closing on a raised deck.