The flow rate of Roots blower is affected by factors such as model, speed, design parameters, and operating conditions. The following analysis is conducted from different dimensions:
1、 Typical flow range
Conventional models: The flow range of Roots blowers is generally between 0.5-300 m3/min, with significant differences in flow rates among different models. For example:
CSR150 type: flow range of 10.39-27.05 m3/min, suitable for small and medium-sized industrial scenarios.
CSR150H type: flow range of 9.53-25.76 m3/min, stronger pressure boosting ability, suitable for high-pressure conditions.
High flow customized model: can be customized up to 1200 m3/min, but requires multiple units in series or special design.
2、 The relationship between flow rate and rotational speed
Linear proportional: The flow rate (Q) of the Roots blower is linearly proportional to the speed (n), with the formula Q=n × V (V is the displacement per revolution). For example:
100 type Roots blower:
At a speed of 1060 rpm, the flow rate is 3.46 m3/min;
At a speed of 1460 rpm, the flow rate increases to 5.56 m3/min;
At a speed of 1780 rpm, the flow rate reaches 7.25 m3/min.
Speed regulation method:
Variable frequency drive regulation: By adjusting the motor frequency, stepless speed regulation is achieved with high precision in flow control.
Replacing the pulley: changing the transmission ratio to adjust the speed, but the adjustment range is limited.
3、 Other factors affecting traffic
Boosting (pressure):
The flow rate of Roots blower is less affected by pressure changes and can remain relatively stable within the rated pressure range. For example, the pressure rise range of CSR150 is 9.8-58.8 kPa, with minimal flow fluctuations.
Pipeline resistance:
Unreasonable pipeline layout (such as too many bends and too small pipe diameter) can increase wind resistance, resulting in actual flow rates lower than the rated value. Optimizing pipeline design can increase the upper limit of flow.
Equipment wear and tear:
The wear of components such as rotors, bearings, and seals can lead to internal leakage and reduce flow rate. Regular maintenance (such as replacing bearings and seals) can maintain stable flow.
4、 Flow regulation method
Variable frequency speed regulation:
Install a frequency converter to achieve stepless flow control by adjusting the motor frequency, suitable for scenarios that require flow control.
Bypass valve regulation:
By adjusting the opening size of the bypass valve, the effective flow rate of the fan can be controlled. The smaller the opening, the greater the effective flow rate; Conversely, it decreases.
Replace the impeller or pulley:
Replacing impellers of different diameters or adjusting the size of pulleys can change the output flow rate of the fan, but it requires shutdown operation and is suitable for long-term working condition adjustment.
Optimize pipeline layout:
Reduce resistance components such as elbows and valves, lower pipeline resistance, and increase the upper limit of flow.
5、 Selection and application suggestions
Select based on operating conditions:
Low pressure high flow: Choose a conventional model (such as CSR150) with a flow range of 10-30 m3/min.
High pressure low flow: Choose a high pressure model (such as CSR150H) with a pressure range of 63.7-98 kPa.
Traffic redundancy design:
In actual selection, the flow rate should be slightly higher than the required value (usually leaving a margin of 10-20) to cope with changes in system resistance.
Maintenance and monitoring:
Regularly inspect components such as bearings, seals, and gearboxes to ensure stable flow.
Install a flow meter to monitor the real-time operation status of the fan.
