How Counterbalanced and Rough Terrain Vertical Mast Forklifts Differ
Counterbalance forklifts and rough terrain vertical mast forklifts look alike, sound alike, and even smell alike (sort of). So are they the same thing?
Not really.
Technically, conventional counterbalance forklifts fall into separate Industrial Truck Association classifications. Counterbalance forklifts can be either Class 1 (Electric Rider Trucks), Class 4 (ICE Cushion Tire Trucks), or Class 5 (ICE Pneumatic Tire Trucks), rough terrain vertical mast forklifts get their own ICE classification, Class 7 (Rough Terrain Trucks).
Different Classifications
Class 7 trucks have pneumatic tires and are almost exclusively powered by diesel engines and used outdoors, according to the ICE. Some trucks are equipped with a traditional (fixed) mast while others use a telescopic style mast. JLG, Load Lifter and Manitou all make rugged rough terrain units and Manitou offers a truck mounted forklift.
Still, there are enough similarities between the two forklift types that operators who are trained on one are often authorized to operate the other — as long as they are familiar with a few key differences.
Capacity, Size, and Weight
Rough terrain vertical mast forklifts are specially designed to handle heavier than normal loads. So the vehicles themselves tend to be bigger and heavier than traditional counterbalance forklifts.
As a result, they typically need more room to operate. Also, operators need to ensure that they are on a driving surface that provides adequate support.
Operating RTVM forklifts on muddy, soft ground or on bridges or other platforms, can be tricky. Drivers need to be aware of load capacities and other condition-related factors.
Tire Differences
RTVM forklifts always come equipped with air-filled tires, also called pneumatic tires. In some instances, they also may contain liquid ballast or foam-filled tires.
A decal or plate on the vehicle should indicate if it is equipped with these specialized types of tires. If so, additional precautions need to be taken. Only authorized personnel are qualified to fill or service ballast tires.
Fork Differences
RTVM forklifts usually are shaft mounted, which means there is an “eye” at the top shank that fits onto a shaft, as opposed to conventional counterbalance forklifts which are generally attached to the carriage at the lower end of the back of the fork.
The bottom of shaft-mounted forks can swing up and away from the vehicle’s carriage while backing out from a load. This can cause the tips to swing upward as well, so drivers need make certain the forks get a clean exit while backing out of loads.
Another fork difference is the thickness. Forks on RTVM tend to be thicker in order to accommodate the heavier loads, so operators need to bear this in mind when assessing how much room is needed for the forks before lifting loads.
Mast Differences
Because they aren’t designed to operate indoors, RTVM forklifts don’t have any free lift, so as soon as the forks start to rise, the second stage of the mast will rise as well.
In some cases, the controls in the cab or an RTVM can be configured differently than a traditional counterbalance forklift. So it’s important that the operator become familiar with them before operating the vehicle in real-life operational situations.