**Professional selection guide for Roots blower for powder conveying**
Powder conveying is a common process requirement in industrial production, and Roots blower has become the core equipment of powder pneumatic conveying system due to its stable air volume and strong anti clogging ability. The following is a professional selection plan for Roots blowers for powder conveying conditions:
1、 Key parameters of powder conveying system
1. * * Conveying Capacity * *:
-Powder characteristics: bulk density (kg/m3), particle size distribution, moisture content
-Conveying capacity range: 0.5-50 tons/hour (under normal operating conditions)
2. * * System pressure requirements * *:
-Low pressure transmission: 9.8-39.2kPa (short distance<50m)
-Medium pressure transmission: 39.2-78.4kPa (medium distance 50-150m)
-High pressure transmission: 78.4-98kPa (long distance>150m)
3. Gas solid ratio:
-Dilute phase transportation: 10-30 (gas-solid ratio)
-Dense phase transportation: 5-15 (gas-solid ratio)
2、 Professional selection plan
1. Wear resistant configuration scheme:
-Impeller: Surface coated with tungsten carbide (hardness C65+)
-Gap Design: Adopting an enlarged gap structure (0.4-0.6mm)
-Sealing system: triple labyrinth seal+airtight seal
-Recommended model: - W series wear-resistant type
2. Explosion proof configuration scheme:
-Motor: ExdIICT4 explosion-proof grade
-Shell: Static grounding treatment
-Temperature monitoring: Built in PT100 temperature sensor
-Recommended model: Ex explosion-proof series
3. * * Food grade configuration plan * *:
-Material: 316L stainless steel
-Surface treatment: mirror polishing (Ra ≤ 0.8 μ m)
-Lubrication system: food grade grease
-Recommended model: HC-FS food grade series
3、 Suggestions for system support
1. * * Pre processing system * *:
-Rotary valve: Ensure quantitative feeding
-Iron remover: protecting the fan impeller
-Drying machine: Control the moisture content of the material to be less than 1
2. * * Post processing system * *:
-Cyclone separator: primary separation
-Bag filter: fine filtration
-Silencer: noise control<85dB
4、 Optimization of operating parameters
1. * * Operating pressure * *:
-Suggested work pressure=system resistance x 1.1 (coefficient)
-Pressure ≤ 90% of rated pressure
2. * * Speed Control * *:
-Recommended speed: 1500-2200rpm
-Variable frequency control: adjustment range 30-50Hz
3. * * Temperature Monitoring * *:
-Bearing temperature: ≤ 95 ℃ (alarm value)
-Exhaust temperature: ≤ 120 ℃ (alarm value)
5、 Maintenance and upkeep standards
1. * * Daily check * *:
-Vibration value: ≤ 4.5mm/s (RMS)
-Lubricating oil: replace every 500 hours
-Filter: Replace when pressure difference>5kPa
2. * * Regular maintenance * *:
-Every 3000 hours: Check the impeller clearance
-Every 6000 hours: Replace bearings
-Every year: dismantling and inspection
6、 Common fault handling
|Fault phenomenon | Possible cause | Solution|
|---------|---------|---------|
|Air volume drops by more than 20% | Impeller wear/filter blockage | Replace impeller/filter element|
|Abnormal vibration | Bearing damage/rotor dynamic balance failure | Bearing replacement/dynamic balance operation|
|High temperature | Poor lubrication/System overpressure | Oil change/Check system resistance|
7、 Selection service process
1. Provide powder characteristic parameters
2. Confirm the schematic diagram of the conveying system
3. Calculate the system resistance curve
4. Determine the working point of the fan
5. Provide a selection report
Note: It is recommended to configure a backup unit to ensure continuous production. For special working conditions, customized solutions can be provided.
