How to adjust the air volume of Roots blower
The air volume adjustment of Roots blower can be achieved by adjusting the motor speed, using a frequency converter, replacing the pulley, or adjusting the bypass valve. Among them, the frequency converter is flexible and energy-saving, and replacing the pulley directly affects the overall speed, while adjusting the bypass valve can control the inlet and outlet air flow. When adjusting, attention should be paid to avoiding incorrect methods, ensuring stable operation of the fan in the rated environment, and paying attention to parameters such as roller bearing temperature, lubricating oil, and vibration speed.
The air volume adjustment of Roots blower can be mainly achieved through the following methods:
Adjust the speed of the electric motor：
Principle: The speed of the electric motor is directly proportional to the air volume. Increasing the speed will increase the air output of the Roots blower.
Method: Adjust the motor speed directly or use a frequency converter to adjust the motor speed.
Attention: The general adjustment range is around 800-1600 revolutions per minute, and it is not recommended to exceed 1700 revolutions per minute, as excessive speed may cause gear wear and increase the operating noise of the machine.
Adjust the motor frequency converter：
Principle: The function of the frequency converter is to adjust the speed of the motor, thereby regulating the air volume of the Roots blower.
Method: Use a frequency converter to flexibly adjust the speed of the motor.
Advantages: It can flexibly adjust the speed of the fan and also save electricity.
Replace the pulley：
Principle: By replacing pulleys of different diameters, the overall speed of the Roots blower can be directly affected, thereby changing the output air volume of the blower.
Method: Adjust the size of the motor pulley. For example, if you want the main engine to rotate faster, you can reduce the size of the motor pulley; Otherwise, increase it.
Attention: Although this method is commonly used, it is not flexible enough.
Adjust the bypass valve：
Principle: Roots blowers are usually equipped with adjustable bypass valves. By adjusting the opening degree of the valve, the inlet and outlet air flow of the fan can be controlled, achieving the adjustment of air volume.
Method: The more the valve is opened, the greater the ventilation and the lower the flow rate; The lower the opening of the intake valve, the lower the air leakage and the greater the flow rate.
When adjusting the air volume of a Roots blower, attention should be paid to avoiding incorrect methods, such as adjusting the outlet valve or pipeline, adjusting the fan "blades" (referred to as "impellers" in the Roots blower industry), and adjusting the intake flow rate, which may affect the normal use of the fan and even cause damage to the motor. Meanwhile, during the operation of the Roots blower, timely monitoring of parameters such as roller bearing temperature, lubricating oil condition, and vibration speed helps ensure stable operation of the equipment in the rated environment.