Elmo Rietschle Roots Vacuum Pumps WH, WS, WHR, WSR, DVP series - Rotary Lobe Pumps for Industrial Applications
Elmo Rietschle Roots Vacuum Pumps - High-Performance Rotary Lobe Pumps
Elmo Rietschle Roots Vacuum Pumps (also called rotary lobe pumps or rotary piston pumps) are among the most powerful vacuum pumps for industrial high vacuum applications. These dry-running pumps achieve pumping speeds of 50-7,500 m³/h and an ultimate vacuum below 1 mbar when combined with backing pumps.
Elmo Rietschle Roots Vacuum Pump Product Range:
1. WH Series - Horizontal Roots Pumps
- 17 models from WH 50 to WH 7500
- Pumping Speed: 50-7,500 m³/h at 50 Hz
- Pressure Differential: up to 53 mbar
- Design: Horizontal, space-saving
- Power: 0.55-45 kW
- Application: Universal for medium to high vacuum ranges
2. WS Series - Vertical Roots Pumps
- 17 models from WS 50 to WS 7500
- Pumping Speed: 50-7,500 m³/h at 50 Hz
- Pressure Differential: up to 53 mbar
- Design: Vertical, minimal footprint
- Power: 0.55-45 kW
- Advantage: Very compact design, ideal for limited space
3. WHR Series - Horizontal Roots Pumps with Gas Recirculation
- 15 models from WHR 120 to WHR 4000
- Pumping Speed: 120-4,000 m³/h at 50 Hz
- Pressure Differential: up to 53 mbar
- Special Feature: Integrated gas recirculation for better cooling
- Advantage: Higher pressure differential possible, better temperature stability
4. WSR Series - Vertical Roots Pumps with Gas Recirculation
- 15 models from WSR 120 to WSR 4000
- Pumping Speed: 120-4,000 m³/h at 50 Hz
- Pressure Differential: up to 53 mbar
- Design: Vertical with gas recirculation
- Ideal for: Compact installation with higher pressure differential
5. DVP Series - Special Roots Pumps
- 9 models from DVP 30 to DVP 710
- Pumping Speed: 30-710 m³/h
- Special Design: For special requirements
- Application: Specific industrial processes
WH 50, WH 120, WH 230, WH 330, WH 500, WH 700, WH 1000, WH 1400, WH 1700, WH 2100, WH 2500, WH 2800, WH 3300, WH 4000, WH 4700, WH 6000, WH 7500, WS 50, WS 120, WS 230, WS 330, WS 500, WS 700, WS 1000, WS 1400, WS 1700, WS 2100, WS 2500, WS 2800, WS 3300, WS 4000, WS 4700, WS 6000, WS 7500, WHR 120, WHR 230, WHR 330, WHR 500, WHR 700, WHR 1000, WHR 1400, WHR 1700, WHR 2100, WHR 2500, WHR 2800, WHR 3300, WHR 4000, WSR 120, WSR 230, WSR 330, WSR 500, WSR 700, WSR 1000, WSR 1400, WSR 1700, WSR 2100, WSR 2500, WSR 2800, WSR 3300, WSR 4000, DVP 30, DVP 42, DVP 70, DVP 84, DVP 120, DVP 240, DVP 360, DVP 490, DVP 710
Operating Principle of Roots Vacuum Pumps:
In Roots pumps (rotary lobe pumps), two figure-eight-shaped rotors rotate against each other in the housing without contact. Synchronization occurs via an external gear drive. Gas is transported from inlet to outlet without being compressed (displacement principle). The actual compression is performed by a downstream backing pump.
Technical Advantages of Rietschle Roots Pumps:
- ✓ Very High Pumping Speed - ideal for large volumes
- ✓ 100% Oil-Free - no process contamination
- ✓ Dry Running - no operating fluids in pumping chamber
- ✓ Contact-Free Operation - minimal wear, long service life
- ✓ High Vacuum Range - effective from 10 mbar to below 0.001 mbar
- ✓ Fast Evacuation - short pumping times
- ✓ Low Maintenance - long maintenance intervals
- ✓ Energy Efficient - high efficiency
- ✓ Compact Design - space-saving installation
- ✓ Quiet Operation - optimized sound damping
Roots Pumps in Combination with Backing Pumps:
Roots pumps always work in combination with a backing pump, as they cannot pump against atmospheric pressure themselves. Typical combinations:
| Backing Pump Type | Ultimate Vacuum | Advantages | Application |
|---|---|---|---|
| Rotary Vane Pump (oil-free) | 1-10 mbar | Oil-free, low maintenance | Standard applications |
| Rotary Vane Pump (oil-lubricated) | 0.001-0.1 mbar | Deep ultimate vacuum | High vacuum applications |
| Claw Pump | 10-50 mbar | Oil-free, robust | Industry, chemistry |
| Liquid Ring Pump | 33-100 mbar | Moisture insensitive | Wet/aggressive media |
| Screw Pump | 0.01-1 mbar | High compression, oil-free | Semiconductor, coating |
Main Application Areas:
- Semiconductor Industry: Wafer manufacturing, etching, CVD processes, sputtering
- Coating Technology: PVD, vapor deposition, cathode sputtering
- Metallurgy: Vacuum melting, vacuum casting, degassing
- Chemical Industry: Distillation, drying, reactors, polymerization
- Pharmaceutical Industry: Freeze-drying, sterilization, crystallization
- Food Industry: Freeze-drying, concentration, aroma extraction
- Research & Development: High vacuum chambers, particle physics, materials research
- Plastics Industry: Extrusion, degassing, polymerization
- Glass Industry: Vacuum glazing, insulating glass production
- Refrigeration Technology: Evacuation of refrigeration and air conditioning systems
- Vacuum Furnaces: Heat treatment, sintering, brazing
- Electronics: Electron microscopes, mass spectrometers
- Solar Technology: Production of solar cells and thin-film modules
Roots Pumps vs. Other Vacuum Pumps:
| Criterion | Roots Pump | Rotary Vane (oil-free) | Claw Pump |
|---|---|---|---|
| Pumping Speed | ✓ Very high (50-7,500 m³/h) | ○ Medium (3-150 m³/h) | ○ Medium (60-1,000 m³/h) |
| Ultimate Vacuum | ✓○ 100-150 mbar○ 50-250 mbar | ||
| Pumping Speed | ✓ Very fast | ○ Moderate | ○ Moderate |
| Backing Pump Required | ✗ Yes, mandatory | ✓ No | ✓ No |
| Investment Costs | ✗ Higher (system) | ✓ Lower | ○ Medium |
| Operating Costs | ○ Medium | ✓ Low | ✓ Low |
| Maintenance | ✓ Very low maintenance | ✓ Low maintenance | ✓ Low maintenance |
WH/WHR vs. WS/WSR - Horizontal or Vertical?
| Property | WH/WHR (Horizontal) | WS/WSR (Vertical) |
|---|---|---|
| Footprint | ○ Larger floor area | ✓ Minimal floor area |
| Installation | ✓ Easier | ○ Special mounting |
| Maintenance | ✓ Easier access | ○ Access from above |
| Height | ✓ Low build height | ○ Higher build height |
| Application | Standard installation | Limited space |
Standard vs. Gas Recirculation (H/S vs. HR/SR):
- Standard (WH/WS): For moderate pressure differentials up to approx. 30 mbar
- With Gas Recirculation (WHR/WSR): For higher pressure differentials up to 53 mbar through internal cooling
Our Complete Service for Rietschle Roots Vacuum Pumps:
- ✓ Sales: New Roots pumps of all series and sizes
- ✓ System Design: Optimal combination of Roots and backing pump
- ✓ Spare Parts: Rotors, bearings, seals, gears, gear units in stock
- ✓ Accessories: Silencers, valves, pressure switches, controls
- ✓ Maintenance: Regular inspections and preventive maintenance
- ✓ Repair & Overhaul: Professional general overhaul
- ✓ Exchange Service: Minimal downtime through rental units
- ✓ On-Site Service: Installation, commissioning, training
- ✓ Complete Systems: Vacuum systems with controls, backing pump, and accessories
Selection Guide - Important Questions:
- What chamber volume needs to be evacuated? (liters or m³)
- What ultimate vacuum is required? (mbar absolute)
- What pumping time is desired? (seconds/minutes)
- Are there gas loads? (outgassing, process gases)
- What medium? (air, inert gas, aggressive gases)
- Operating mode: Continuous or cyclic?
- Space constraints: Horizontal or vertical preferred?
- Backing pump available? If yes, which one?
Why Elmo Rietschle Roots Vacuum Pumps?
- ✓ World-leading manufacturer of Roots technology
- ✓ Over 100 years of experience in vacuum technology
- ✓ Highest quality and reliability
- ✓ Comprehensive product range from 50-7,500 m³/h
- ✓ Worldwide availability of spare parts
- ✓ Proven technology in thousands of installations worldwide
- ✓ Excellent service and support