Laden, Unladen and High Capacity Forklifts

So you are the manager of a fleet of forklifts that need to carry shipping containers that are as large as 20-feet to 40-feet or more in length. Warehouse forklifts are probably too small and lightweight to handle the extra bulk. Instead, laden, unladen or high capacity forklifts are needed.

The laden forklift is the larger, heavier option of the three. They have to be heavy and large so that they can handle as much as 50 tons of weight. They also incorporate a number of features not found on the smaller lifts including:

· A larger counter-weight to steady the vehicle.
· A larger overall turning radius that makes the vehicle less maneuverable.
· A tough vista mast capable of stacking five laden containers with slower lift speeds to assure safe lifting of heavy loads.
· A more powerful diesel engine to handle heavier load weights.

Unladen forklifts are smaller because they are needed to lift empty shipping containers that weigh a lot less than the loaded ones. Therefore, these machines are designed with different features that include:

· Smaller counter-weight because the containers that need to be balanced are lighter.
· A smaller turning radius to permit operation in smaller areas with more maneuverability.
· A smaller diesel engine.

In addition, unladen forklifts feature multiple engagement systems, including:

· Twist locks
· Twist locks with moveable heads.
· Double horizontal twist locks.
· Hooks and side clamps.

The third option, high capacity forklifts, offers a multipurpose solution for container handling.

Nowadays, as many as 75 percent of the 20-feet ISO containers in use include fitted fork pockets. These pockets enable a high capacity forklift to lift a container without the use of any specialized lifting attachment as long as the lift is capacity rated to lift the load.

These lifts are versatile enough to lift laden and unladen containers as well as other large, heavy materials. Moreover, they are cost effective to own. Benefits include:

· No need for specialized lifting attachments.
· The forklift is always in use.
· Multiple style forklifts are not necessary to handle different material handling operations.

When considering higher capacity forklifts don’t forget about the forklift mast. The mast is the vertical assembly on the front of the lift that raises, lowers, and tilts the load.

There are single stage, two stage, three-stage, and four-stage masts. The single stage mast features one channel and has a limited tilt height. These masts are commonly used in self-propelled or walk-behind equipment.

A two-stage mast has a standard limited free lift of about 4-feet, 6-inches and is used for lower lift heights. Two stage masts are commonly used on high capacity forklifts of 15,000 lbs. and up.

Three-stage mast is the most commonly used. It includes three sections that extend the forks to their maximum lift height. Typical lift height for a triple stage mast for a forklift with base capacity is from 2,000 lbs. to 6,000 lbs.

A four-stage (or quad) mast features four sets of rails that raise the load. It generally features a primary lift cylinder so it can deliver a full free lift. It is ideal for loading and unloading higher-tiered stacks.

The mast is attached to the carriage and the carriage is attached to the forks. A hydraulic piston in the middle of the mast raises it up and down. Hydraulic displacement raises the mast and the force of gravity lowers it.