What Is a Roots Blower?
A roots blower is primarily utilized for air blowing, achieved by rotating a pair of blade-shaped rotors.
These blowers typically consist of 2 to 4 blades. The greater the number of blades, the more air can be blown per rotation, thus enhancing efficiency.
The rotor shapes are broadly categorized into involute, cycloidal, and envelope types.
Uses of Roots Blowers
Roots blowers find their application in several areas:
- Water Treatment Facilities
They are employed in septic tanks at water treatment facilities in various institutions like factories, schools, hospitals, etc., for aerating the tanks. - Industrial Vacuum Cleaners
Roots blowers are integral in vacuum cleaners and dust collectors used in factories for suctioning dust and air, and subsequently exhausting purified air. - Vacuum Trucks
They are used in vacuum trucks for suctioning sludge and debris in cleaning operations. - Welding Fumes Extraction
In factories, they are used in industrial vacuum cleaners to extract fumes generated during welding and capture them in filters. - Air Blowing in Factories
Employed in powering air blowers for removing moisture from products in manufacturing settings.
Principles of Roots Blowers
Roots blowers are designed with a housing body featuring an intake hole and an exhaust hole. Rotors within the blower draw air in through the intake and expel it through the exhaust. During operation, a small gap is maintained between the rotor and the housing, as well as between the rotors themselves, ensuring that they rotate without making contact.
The rotation direction is from the intake chamber to the exhaust chamber, pushing air from the intake to the exhaust. The efficiency of the blower is higher when the gap between the rotor and housing, and between the rotors, is narrower, as this minimizes leakage.
However, an overly narrow gap can risk rotor lock due to foreign objects entering the housing, leading to rotation failure. Therefore, the choice of Roots blower should consider the cleanliness of the operational environment.
Roots blowers are predominantly used in two or three-blade configurations. The two-blade type discharges air four times per revolution, while the three-blade type can discharge six times per revolution, enhancing efficiency but also increasing costs due to the complexity of rotor machining.