Gear pumps are essential components in agricultural tractors, providing the hydraulic power necessary for various agricultural operations. They are designed to generate high-pressure fluid flow, enabling the efficient operation of implements and attachments.

1. External Gear Pump:

The external gear pump is one of the most common and widely used types of gear pumps in agricultural tractors. It consists of two intermeshing gears - an outer gear and an inner gear - enclosed within a casing. The teeth on these gears form sealed chambers that capture and transport hydraulic fluid. As the gears rotate, the fluid is carried from the inlet to the outlet, generating pressure and delivering hydraulic power.

Subsections:

a. Construction:

The external gear pump's construction typically involves a cast iron or aluminum casing that houses the gears. The gears themselves are precision-machined to ensure tight tolerances and optimal fit. The pump also includes inlet and outlet ports for hydraulic fluid.

Working Principle:

The working principle of an external gear pump relies on the meshing of the gears to create sealed chambers between the teeth. As the gears rotate, the chambers expand, allowing fluid to enter the pump through the inlet port. As the chambers decrease in size, hydraulic fluid is forced out through the outlet port, generating pressure and power.

c. Applications:

External gear pumps are used in various hydraulic systems within agricultural tractors. They provide power for hydraulic motors, cylinders, and other components, enabling functions such as raising and lowering implements, controlling steering, and managing auxiliary systems.

Advantages:

External gear pumps offer several advantages in agricultural tractor applications. They are relatively simple in design, resulting in lower cost and ease of maintenance. External gear pumps are known for their efficiency, reliability, and ability to handle high-pressure applications. Their compact size also allows for flexible installation options in tractors with limited space.

2. Internal Gear Pump:

Internal gear pumps, also known as gerotor pumps, are another commonly used gear pump type in agricultural tractors. Like external gear pumps, they consist of interlocking gears enclosed within a casing. However, the design and operation of internal gear pumps differ from their external counterparts, offering distinct advantages and applications.

Subsections:

Construction:

Internal gear pumps feature an outer rotor and an inner rotor with teeth that mesh together. The outer rotor has one more tooth than the inner rotor, creating multiple chambers or pockets between the teeth. The pump casing contains inlet and outlet ports for hydraulic fluid.

Working Principle:

The working principle of an internal gear pump involves the rotation of the outer rotor. As the outer rotor rotates, the pockets between the teeth capture hydraulic fluid through the inlet port. The fluid is then carried around the outer rotor until it reaches the discharge point, where it is forced out through the outlet port.

Applications:

Internal gear pumps are commonly used in agricultural tractors for applications that require precise control and compact size. They are suitable for powering systems such as implementing hydraulics, hydraulic steering, and transmission controls. Additionally, their ability to handle a wide range of viscosities makes them ideal for applications that require fluid transfer or circulation.

Advantages:

Internal gear pumps offer several advantages for agricultural tractor applications. They are known for their efficiency, especially at lower speeds and pressures, which aligns with the typical operating conditions of agricultural machinery. Internal gear pumps also provide smooth and precise fluid flow, making them suitable for applications that require accurate control and response. Furthermore, their compact size allows for integration into tight spaces, maximizing design flexibility.