**Technical Explanation of High Pressure Roots Blowers (Selection/Application/Maintenance Guide)**
**1、 Definition standard for high-pressure Roots blower**
1. * * Pressure Classification * * (GB/T 1236 standard)
-Normal type: ≤ 49kPa (0.5kgf/cm2)
-High pressure type: 49-98kPa (0.5-1.0kgf/cm2)
-Ultra high pressure type:>98kPa (special design required)
2. * * Structural reinforcement features**
```mermaid
graph TB
A [High Voltage Design] -->B [Reinforced Gear]
A -->C [Three layer shaft seal system]
A -->D [Thickened casing]
A -->E [Dual oil tank lubrication]
```
**2、 Core parameter range**
|Parameters | Typical Values | Technical Description|
|---------------|--------------------|-------------------------|
|Flow range | 5-150 m3/min | Parallel use is required for flow rates greater than 80m3/min|
|Work pressure | 49-98 kPa | up to 120kPa (customized)|
|Power configuration | 22-250 kW | 7-8 additional power required for every 10kPa pressure rise|
|Speed | 980-1750 rpm | Low speed prolongs lifespan|
**3、 Key component reinforcement design**
1. * * Rotor system**
-Impeller material: QT500-7 ductile iron (HB220-260)
-Gap control: 0.25-0.35mm (laser calibration required)
-Dynamic balance level: G2.5 level (ISO 1940)
2. * * Sealing system**
-Adopting a three-stage combination of "labyrinth seal+mechanical seal+nitrogen seal"
-Leakage rate ＜ 0.5 rated flow rate
3. * * Gearbox**
-Modulus ≥ 8, carburizing and quenching hardness C58-62
-Oil bath lubrication+forced spray dual system
**4、 Selection Calculation Example**
**Case * *: Cement transportation requires 80kPa@40m3 /min
1. Power estimation:
```
N = (Q×ΔP)/(6120×η) = (40×80)/(6120×0.68) ≈ 77kW
(η is taken as 0.68, including mechanical losses)
```
2. Selection results:
-Model: -200H
-Power: 90kW (with a reserved margin of 15)
-Speed: 1250rpm
**5、 Special application configuration**
|Working conditions | Solutions | Diagram symbols|
|----------------|-----------------------------|----------------------|
|High temperature gas (≤ 200 ℃) | water-cooled jacket+temperature resistant seal | →→|
|Corrosive medium | 316L stainless steel impeller+PTFE seal |+|
|Explosion proof requirements | Ex d Ⅱ CT4 motor+grounding device | →|
**6、 Maintain monitoring standards**
1. * * Online monitoring parameters**
-Vibration value: ≤ 4.5mm/s (ISO 10816)
-Oil temperature: ≤ 75 ℃ (alarm value 85 ℃)
-Gear meshing spot: ≥ 60 contact area
2. * * Overhaul cycle**
```mermaid
gantt
Title High pressure Roots blower overhaul plan
Section regular maintenance
Oil replacement: a1, January 1, 2024, 2000h
Sealing inspection: a2, after a1, 500h
Key components of the section
Bearing replacement: Crit, June 1, 2024, 15000h
Impeller refurbishment: Crit, January 1, 2025, 30000h
```
**7、 Fault Tree Analysis (FTA)**
```mermaid
graph TD
A [Insufficient Pressure] -->B {System Troubleshooting}
B -->C [filter clogged]
B -->D [Increased internal leakage]
D -->E [Impeller wear]
D -->F [Sealing Failure]
E -->G [Gap exceeds tolerance]
F -->H [seal aging]
```
**8、 Energy efficiency optimization plan**
1. * * Variable frequency control strategy**
-Automatically adjust the speed based on back pressure
-The energy-saving rate can reach 18-35%
2. * * Heat recovery system**
-Lubricating oil heat is used for process preheating
-Recycling efficiency ≥ 55
**9、 Mainstream models in the market**
|Brand | High Pressure Series | Pressure | Featured Technologies|
|-----------|-------------|------------|----------------------|
|| - H | 98kPa | Double support gearbox|
|JG-HP | 108kPa | Laser alignment correction|
|| Series | 120kPa | Modular Design|
**10、 Selection precautions**
1. * * Pressure margin * *: Selection pressure=Actual demand x 1.1 times
2. * * Parallel operation * *: When there are ≥ 3 units, a pressure equalization tube must be installed
3. * * Start protection * *: Pressure relief valve and soft start must be configured
4. * * Altitude correction * *: For every 1000m increase, the air volume decreases by 8
**Note * *: For ultra-high pressure requirements greater than 100kPa, it is recommended to consider the "Roots+Centrifugal" series unit scheme. Specific selection requires providing parameters such as medium composition and annual operating hours.
