The following is the * * High pressure Roots blower selection parameter table * * and key selection guide, covering core parameters such as flow rate, pressure, power, speed, etc., suitable for high-pressure scenarios such as sewage treatment, pneumatic conveying, chemical industry, etc. (usually referring to Roots blowers with exhaust pressure * * ≥ 49kPa (0.5bar) * *).
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**High pressure Roots blower selection parameter table**
|* * Parameter Name * * | * * Unit * * | * * Selection Range * * | * * Explanation * *|
|--------------------|----------|----------------------------|-------------------------------------------------------------------------|
|* * Exhaust pressure * * | kPa (bar) | * * 49~200 kPa (0.5~2.0 bar) * * | High pressure type is usually ≥ 49kPa, and a margin of 10 should be reserved to prevent overpressure|
|Flow rate (air volume) * * | m3/min | * * 1~200 m3/min * * | Actual flow rate needs to be corrected according to operating temperature and altitude (standard state: 20 ℃, 101.3kPa)|
|Motor power * * | kW | * * 5.5~355 kW * * | Power is positively correlated with pressure and flow rate, and high power should be selected when under high pressure (reference formula: power ∝ flow rate × pressure)|
|* * Speed * | rpm | * * 980~3000 rpm * * | Low speed (980~1500rpm) should be selected for high-pressure fans to reduce wear and noise|
|Medium temperature * * | ℃ | * * ≤ 80 ℃ * * | Special materials (such as stainless steel) or cooling systems are required for temperatures exceeding 80 ℃|
|Noise level * * | dB (A) | * * 75~95 dB (A) * * | High pressure fans have high noise levels and require mufflers or soundproof covers|
|* * Import and export caliber * * | mm | * * DN50~DN300 * * | According to the flow rate selection, the flow velocity should be controlled within 10~15m/s|
|* * Transmission mode * * | - | Direct connection/belt | High voltage recommended direct connection (high efficiency), high-power optional belt (buffering vibration)|
|Sealing method * * | - | Maze seal/mechanical seal | Mechanical seal is required for corrosive gases|
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**2、 Key steps for high voltage selection**
1. * * Determine the working condition requirements**
-* * Pressure * *: System resistance (pipeline+equipment pressure loss)+10 margin.
-Flow rate: Calculated according to process requirements and converted to standard state flow rate (if the operating conditions are non-standard).
-Media: clean air, corrosive gases, dust, etc. (determining material and sealing).
2. * * Select the type of fan**
-* * Two leaf type * *: suitable for high flow and medium pressure (≤ 98kPa).
-* * Three leaf type * *: Suitable for high-pressure (>98kPa) and low pulsation scenarios (with lower noise).
3. * * Calculate motor power**
-Simplified formula:
\[
P=\ frac {Q \ times P_a \ times K} {60 \ times \ eta} \ quad (\ text {unit: kW})
\]
-(Q): Flow rate (m3/min)
-(P_a): Exhaust pressure (kPa, absolute pressure=gauge pressure+10.13kPa)
-(K): Coefficient (1.1~1.2)
-(eta): Mechanical efficiency (usually 0.7~0.9)
4. * * Verify special requirements**
-Explosion proof: ExdIIBT4 grade (chemical, coal mining, etc.).
-Anti corrosion: Stainless steel impeller/casing (such as 316L).
-Cooling: water-cooled jacket (medium temperature>80 ℃).
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**3、 Selection Example**
**Case * *: Sewage treatment aeration, required flow rate * * 30m3/min * *, pressure * * 78.4kPa (0.8bar) * *, ambient temperature air.
1. * * Selection Parameters * *:
-Pressure: 78.4kPa+10=* * 86kPa * * (selected pressure range: 98kPa).
-Flow rate: 30m3/min (standard state).
-Power estimation:\ (P=\ frac {30 \ times (98+101.3) \ times 1.1} {60 \ times 0.8} ≈ 45kW \) (Select * * 45kW * * motor).
2. * * Recommended Configuration * *:
-Three leaf Roots blower, direct drive, cast iron material, labyrinth seal, equipped with muffler.
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**4、 Precautions**
1. * * Avoid overpressure operation * *: High pressure fans need to be equipped with * * valves * * and * * pressure gauges * *.
2. * * Starting method * *: For high power (>75kW), it is recommended to use soft start or variable frequency control.
3. Maintenance cycle: High pressure fan bearings/gears need to be lubricated more frequently (checked every 500 hours).
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**5、 Common selection errors**
-Neglecting the characteristics of the medium: Dust containing gas without a filter leads to impeller wear.
-Insufficient pressure margin: Incorrect calculation of pipeline pressure loss and long-term overload of the fan.
-* * High speed * *: Choosing a high-speed fan for high-pressure conditions significantly shortens its lifespan.
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**Tip * *: The final selection should be based on manufacturer samples (such as Changsheng,, etc.), and detailed operating data should be provided to confirm compatibility.
