Roots blowers are positive-displacement machines, featuring impeller end faces and front and rear end covers. They operate on the principle of using two lobe-shaped rotors that move relative to each other within a cylinder to compress and convey gas. This type of blower boasts a simple structure and easy manufacturing, making it widely used for oxygenation in aquaculture, aeration in wastewater treatment, and cement conveying. It is particularly well suited for gas delivery and pressurization applications at low pressures and can also serve as a vacuum pump, among other uses.

　　Roots blowers are positive-displacement machines, featuring impeller end faces and front and rear end covers. They operate on the principle of using two lobe-shaped rotors that move relative to each other within a cylinder to compress and convey gas, making them rotary compressors. This type of blower boasts a simple structure and easy manufacturing, and is widely employed in applications such as oxygenation in aquaculture, aeration in wastewater treatment, and cement conveying. It is particularly well suited for low-pressure gas delivery and pressurization systems and can also serve as a vacuum pump, among other uses.

　　The Roots blower consists of five major components: the casing, wall plates, impeller, oil tank, and silencer.

　　Casing: Primarily serves to support and secure the wall panels, impeller, and silencer.

　　Wall plate: Primarily used to connect the casing to the impeller, support the impeller’s rotation, and provide end-face sealing.

　　Impeller: It is the rotating component of a Roots blower, available in two‑leaf and three‑leaf configurations. However, owing to its numerous advantages—such as reduced outlet pulsation, lower noise levels, and smoother operation—the three‑leaf design has gradually replaced the two‑leaf Roots blower.

　　Oil tank: Primarily used to store lubricating oil for lubricating gears and bearings.

　　Silencer: Used to reduce noise generated by airflow pulsations at the inlet and outlet of a Roots blower.

　　Roots blowers are a type of positive-displacement blower in which two three-lobe impellers rotate in opposite directions within a sealed chamber formed by the casing and end plates. Each impeller is generated by an involute or an epicycloid envelope, and its three blades are identical; moreover, the two impellers are also identical, significantly simplifying manufacturing. During production, CNC machining ensures that, with a constant center distance, the impellers maintain a very small, consistent clearance regardless of their rotational position, thereby keeping gas leakage within acceptable limits.

　　Two impellers rotate in opposite directions. Due to the extremely small clearances between the impellers themselves, between the impellers and the casing, and between the impellers and the side plates, a vacuum is created at the inlet. Under atmospheric pressure, air enters the intake chamber. Subsequently, each impeller, together with two of its blades and the side plates and the casing, forms a sealed cavity. As the impellers rotate, the air in the intake chamber is continuously carried by these sealed cavities into the discharge chamber. Moreover, because the impellers in the discharge chamber are meshed with one another, the air trapped between the two blades is squeezed out. With this continuous operation, air is steadily conveyed from the inlet to the outlet—this is the entire working process of a Roots blower.

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