Where Does The Power Of A Tractor Come From?

Tractors are known as universal machinery and the king of arable land. It has a huge body and tremendous power, so the question is, where does this power come from? Today, I will take you to unveil this veil together.

The source of energy for tractors is essentially the operation of internal combustion engines. The tractor can travel by relying on the power of the internal combustion engine through the transmission system, which obtains the driving torque Mk from the driving wheels. The driving wheels that obtain the driving torque then generate friction and a tangential force (horizontal backward thrust) that compresses the soil backward through the tire pattern and the contact point between the tire surface and the ground. The horizontal reaction force Pk on the ground, which is equal in magnitude and opposite in direction, is the driving force (tangential traction force) that drives the tractor forward.

The source of energy for tractors is essentially the operation of internal combustion engines. The tractor can travel by relying on the power of the internal combustion engine through the transmission system, which obtains the driving torque Mk from the driving wheels. The driving wheels that obtain the driving torque then generate friction and a tangential force (horizontal backward thrust) that compresses the soil backward through the tire pattern and the contact point between the tire surface and the ground. The horizontal reaction force Pk on the ground, which is equal in magnitude and opposite in direction, is the driving force (tangential traction force) that drives the tractor forward.

The driving force is the horizontal reaction force of the road surface on the driving wheel. Therefore, the magnitude of the driving torque Mk transmitted by the internal combustion engine to the driving wheels through the transmission system indicates that the driving force Pk of the tractor is also greater. However, since Mk is determined by the power of the internal combustion engine, Pk is also limited by the power of the internal combustion engine. At the same time, Pk is limited by soil conditions and cannot be infinitely increased, because when the soil's reaction force, namely the driving force Pk, increases to a certain extent, the soil is destroyed, the driving wheel slips severely, and the driving force Pk cannot be increased anymore. We call the maximum reaction force that the soil can produce on the driving wheel "adhesion".

It can be seen that the maximum value of the driving force Pk is not only limited by the internal combustion engine rate, but also by the soil adhesion, and cannot be infinitely increased. Adhesion reflects the ability of the driving wheel to generate maximum driving force with the soil. There are many factors that affect adhesion, mainly related to ground conditions, tire pressure, size, pattern, and the size of the vertical load acting on the tire.

For tractors, reducing tire pressure, increasing tire support area, improving wheel grip on soil, and increasing wheel attachment weight within a certain range under certain soil conditions are all beneficial for improving tractor adhesion. Low pressure tires are commonly used on tractors, and some tractors use widened tires and high tread tires, as well as adding counterweights to the tractor drive wheels, all of which are measures taken to increase tractor adhesion and improve tractor traction capacity.

However, it should be pointed out that adding counterweight iron to the driving wheel can increase adhesion, but at the same time, it also increases soil deformation in the vertical direction and increases rolling resistance. Therefore, whether to add counterweight iron depends on specific usage conditions and weigh the overall effect before making a decision.