The AP Box grader type SKB is the “mini” version of the large foldable KB grading boxes. The gooseneck drawbar ensures that the material, that is in front of the blade, has plenty of space to “roll”. Furthermore the position of the hitch is much lower than the one on the standard grading boxes. The SKB can be coupled to the lower hitch of the tractor, meaning the coupling point is lower resulting in a lower power requirement.
The position of the drawbar is a determining factor in the permissible volume of material. The result of grading and the power requirements of the tractor depend on the way the ground moves in front of the blade. If the bucket is full and the ground touches the drawbar then the ground will not “roll” anymore because the ground will accumulate under or around the drawbar. The grading box is full and pushes the ground ahead; besides that the grading box may be lifted due to the large amount of ground under the drawbar. This makes accurate levelling impossible and will increase the power requirement and therefore the fuel consumption. All this is prevented by the drawbar construction of the AP Box grader type SKB.
With the use of the SKB box grader the ground will always “roll”, even when the box grader is getting more fuller, thanks to the special shape of the blade with 2 radii. The gooseneck drawbar is positioned at a measured distance from the special blade and the soil so the ground cannot get jammed under the drawbar.