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External Gear Pumps
CHENHUI design and manufacture high-quality micro pumps for precise fluid handling in various industries. Our pumps feature an external gear design, which enhances performance and ensures durability, even in demanding applications. The magnetic drive technology ensures leak-free operation and reduces maintenance needs. Our micro gear pumps offer long-lasting, efficient solutions for applications requiring small-volume, high-precision fluid transfer.
External Gear MIcro Pump Series
Magnetic Drive Pump + Motor Series
Frequent Asked Questions
What is an External Gear Pump?
An external gear pump is a type of positive displacement pump that utilizes two intermeshing gears to move fluid. In this design, one gear acts as the drive gear, and the other is the driven gear.
As the gears rotate in opposite directions, they create a suction effect that draws fluid into the pump. The meshing of the gears then forces the fluid out through the discharge port.
In micro pumps, both gears are typically of the same size. External gear design allows for precise and stable fluid movement.
What are the Advantages of External Gear Pumps?
The main difference between internal and external gear pumps lies in their design and fluid handling method.
In an internal gear pump, one gear is housed inside another, and the meshing of these gears creates a pumping action. Conversely, external gear pumps feature two gears that mesh outside of each other, driving the fluid through the system.
External gear pumps are often more durable and capable of handling higher viscosity fluids, whereas internal gear pumps are generally quieter and more compact.
Are External Gear Pumps Fixed Displacement?
Yes, external gear pumps are fixed displacement pumps. This means that they deliver a consistent volume of fluid with each rotation of the gears. The displacement per cycle remains constant, which makes these pumps reliable for applications requiring a steady flow of fluid.
What is the Principle of an External Gear Pump?
The principle behind an external gear pump is relatively simple. It relies on two gears that rotate in opposite directions. As the gears turn, fluid is drawn into the cavity between the teeth of the gears. The meshing of the gears then forces the fluid to move through the discharge port, creating a steady flow.
Are External Gear Pumps Reversible?
External gear pumps are generally not reversible. They are designed to pump fluid in a specific direction. If you want to reverse the flow direction, you might need to require adjustments to the pump’s configuration.
Can External Gear Pumps Move Fluid in Either Direction?
Most external gear pumps are built to deliver fluid in one specific direction, and attempting to reverse the flow without proper modification could damage the pump or lead to inefficiency.
What Causes Discharge of Fluid in an External Gear Pump?
The discharge of fluid in an external gear pump is caused by the meshing of the two rotating gears. As the gears turn, they create a void or suction, drawing fluid into the pump. The meshing teeth then force the fluid into the discharge port, effectively displacing it.
