•The stability triangle is an effective way to
show an operator how their actions can cause a lift truck to tip over so that
they know what actions to avoid.
•This information on stability is primarily for
sit-down counterbalance lift trucks. Other lift trucks, such as stand-up
narrow aisle, will probably have different stability concerns.
•A sit-down counterbalance lift truck has a
three-point suspension with the weight supported at each front tire and the
center of the rear axle.This creates
a triangle.As long as the combined
center of gravity of the load and the forklift remain within this stability
triangle, the forklift will not tip over.
•The center of gravity of an unloaded forklift
will be just below the operator’s seat.
•With a load, the combined center of gravity
(black circle) is close to the font edge of the stability triangle.
•A near-capacity load with a longer load center
(e.g., 30 inches) will create a combined center of gravity that has moved
beyond the front edge of the triangle.The forklift will tip forward.