How driving wheels of front-loaded tractor interact with the terrain depending on tire pressures

• Peculiarities of driving wheels’ interaction with the terrain.
• For the tractor working with front-mounted loader driving wheels is slip/skid.
• Slip/skid dependences on wheel loads and tire pressures.
• Rational air pressure values for tires of 4WD tractor with front-mounted loader.
• Decreased lead of front driving wheels for the tractor with front-mounted loader.

This paper analyzes peculiarities of wheel interaction with the terrain for 4WD tractors working with front-mounted loaders. When tractor wheels are loaded by a vertical forces that do not correspond to the specified proportions, deformations of front and rear tires also do not correspond to the specified proportions, and this leads to a kinematic discrepancy because of change in ratio between driving wheels’ rolling radiuses. In case of kinematic discrepancy, wheel slip/skid is taking place. In the paper test results are presented, how driving wheels’ slip/skid of 4WD tractors with front-mounted loaders depend on the vertical loads acting on the wheels and their tire inflation pressures. It was determined that there are dependences on relation between front and rear tire pressures, which allow avoiding wheel slip/skid for the 4WD tractor with front-mounted loader that runs without a load and transports loads. By preparing a tractor for work with front-mounted loader, it is advisable for operator to select a set of tires that would ensure the lead of front wheels lesser compared to the lead that is commonly used for traction works. In this case, the operator creates conditions for wheels’ interaction with the terrain without slip/skid at higher inflation pressures in the front tires.