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Effects of incorrect load shape on forklift
Looking at the bottom of these two drawings it can be seen that the load centre in this picture is small and well within the trucks rated load centre of 500 mm.
Assuming the load is turned around and laid down the effect on the load centre dimension can be seen in the top picture where it is obviously exceeded. This is how the shape of an object can affect the stability of the forklift truck.
For the purposes of illustration these drawings are not to scale