Pumps from the PTO of a tractor, a car. The torque from the tractor engine is transmitted to the gearbox, the power take-off shaft. When the speed of the power take-off shaft changes, the speed of rotation of the impeller and the pump rollers also changes. Thus, the characteristics - the pressure and flow rate of the liquid-change. PTO pumps are used for irrigation, pumping, and mixing. Water supply for irrigation.