The pressure range of Roots blower is its core performance indicator, which directly affects the selection of application scenarios. Here is a detailed analysis:
1、 Standard pressure range
1. * * Regular model * *:
-Single stage Roots blower: 9.8~98kPa (0.1~1.0bar)
-Typical working range: 39.2~78.4kPa (0.4~0.8bar)
2. * * High Voltage Model * * (Special Design):
-Up to 147kPa (1.5bar)
-Need to strengthen the gear/bearing system
2、 Extreme pressure limit
1. * * Mechanical limitations * *:
-Critical value of impeller deformation:> 150kPa
-Gear load limit: ≤ 160kPa
2. * * Efficiency turning point * *:
-Efficiency range: 49~78.4kPa
-When the pressure exceeds 98kPa, the volumetric efficiency decreases by 15-20%
3、 Classification of pressure levels
|Pressure level | Scope of application | Typical applications|
|---------|---------|---------|
|Low pressure (<49kPa) | Shallow water aeration, pneumatic conveying | Sewage treatment, grain conveying|
|Medium pressure (49-78.4kPa) | Medium resistance system | Chemical process, electroplating tank|
|High pressure (78.4-98kPa) | High resistance condition | Deep water aeration, vacuum system|
4、 Special working condition pressure correction
1. * * High temperature gas * *:
-For every 100 ℃ increase, the pressure decreases by 8
-Example: 98kPa model at 150 ℃ → actual limited to 90kPa
2. * * High altitude * *:
-The pressure output per kilometer at altitude decreases by 9
-A larger motor is required for the 3000 meter area
5、 Formula for calculating selection pressure
Actual required pressure=1.2 × (pipeline pressure loss+equipment pressure loss)
Among them:
-Pipeline pressure loss=resistance along the way+local resistance
-Equipment pressure loss: such as aerator 49kPa
6、 Abnormal pressure handling
1. Overpressure performance:
-The current exceeds the rated value by 10
-Bearing temperature>85 ℃
-Abnormal vibration (>7.1mm/s)
2. * * Solution * *:
-Immediately check the valve
-Clean up pipeline blockages
-Verify system design resistance
It is recommended to leave a pressure margin of 10-15 when selecting, which ensures reliability and prevents excessive energy consumption. Please refer to the manufacturer's performance curve for the specific allowable pressure of the model.
