Caterpillar fuel pumps
In direct injection engines as well as diesel engines, the Caterpillar electric fuel pump is used in the low pressure circuit for pre-supplying fuel to the high-pressure pump - Caterpillar injection pump. The electric Caterpillar fuel pump creates a fuel pressure in the limit of 0.3-0.4 MPa (in engines with direct injection - up to 0.7 MPa). The use of mechanical pumps in Caterpillar fuel injection systems is not possible due to low fuel delivery pressure.
By design, the following types of electric fuel pumps are distinguished: roller, gear and centrifugal.
In the Caterpillar roller pump, the fuel is sucked and injected by rotating the rotor and moving the rollers therein. As the space between the roller and the rotor increases, a vacuum is created, and the fuel fills this space. When the space is full, the fuel supply is cut off. As the rotor rotates, space decreases, the discharge port opens and the fuel leaves the pump under pressure.
Similarly, the Caterpillar gear pump works where the fuel is sucked and injected by the movement of the inner gear (rotor) relative to the eccentrically located outer gear (stator). The lateral sides of the rotor tooth, during rotation, form in their gaps the changing chambers, with which the fuel is sucked in and injected.
Due to the design features, the Caterpillar roller and gear pumps are installed in the fuel line. In modern injection systems, preference is given to centrifugal or vane Caterpillar pumps, which provide a uniform (without pulsations) fuel supply and produce little noise. At the same time, Caterpillar centrifugal pumps have limitations on the created pressure and productivity.
Centrifugal Caterpillar fuel pump. The impeller rotates inside the chamber, in which there are two channels of a certain shape - suction and discharge. Fluctuations in the fuel resulting from the action of the blades on it provide an increase in pressure.
Short list below: