Pfeiffer CombiLine WD Series Rotary Lobe Vacuum Pump System

Overview

The Pfeiffer CombiLine WD Series is an integrated rotary lobe (Roots) booster vacuum pump system engineered for high-throughput, stable rough-to-medium vacuum generation in demanding industrial and R&D environments. Unlike standalone Roots pumps requiring external forepumping, the CombiLine WD integrates a Pfeiffer DuoLine dual-stage oil-sealed rotary vane pump as the forepump—ensuring seamless pressure staging from atmosphere down to ≤ 5 × 10⁻⁴ mbar. Its operation relies on synchronized, non-contacting rotary lobes driven via hermetically sealed magnetic couplings—eliminating mechanical shaft seals and minimizing oil backstreaming. This architecture delivers robust performance in continuous-duty applications where thermal stability, low vibration, and long-term reproducibility are critical, including physical vapor deposition (PVD), vacuum metallurgy, optical coating, and advanced materials research.

Key Features

• Magnetic coupling drive system: Ensures zero oil contamination from the roots stage into the vacuum chamber and eliminates seal wear—enhancing uptime and reducing maintenance intervals.
• Integrated oil mist filtration: Standard high-efficiency coalescing filter captures >99.9% of aerosolized oil droplets, meeting ISO 8573-1 Class 2 requirements for downstream process integrity.
• Compact modular footprint: Optimized mechanical layout minimizes floor space while maintaining service accessibility—ideal for integration into OEM vacuum chambers, cluster tools, and turnkey systems.
• Thermally stabilized housing: Cast-iron pump body with optimized cooling channels ensures consistent rotor clearance across extended duty cycles, preserving pumping speed accuracy over time.
• DuoLine forepump compatibility: Factory-matched Duo 35/65/125/255 rotary vane pumps provide reliable, low-noise pre-evacuation and backing—each certified per ISO 21809 for ultimate pressure and flow stability.

Sample Compatibility & Compliance

The CombiLine WD series is compatible with inert, reactive, and mildly corrosive process gases (e.g., Ar, N₂, O₂, H₂, and common sputtering or etch precursors), provided gas loads remain within specified hydrocarbon and condensable vapor limits. It is not intended for solvent-laden or highly polymerizing vapors without auxiliary cold traps or scrubbers. All models comply with EU Machinery Directive 2006/42/EC, Electromagnetic Compatibility Directive 2014/30/EU, and RoHS 2011/65/EU. The integrated DuoLine forepumps meet ISO 21809:2019 for ultimate vacuum performance verification. For GMP/GLP-regulated environments, optional audit-trail-capable digital I/O modules support integration with SCADA systems compliant with FDA 21 CFR Part 11 requirements.

Software & Data Management

While the CombiLine WD operates as a stand-alone hardware system, it supports analog (0–10 V / 4–20 mA) and digital (RS-485 Modbus RTU) interfaces for remote status monitoring—including inlet pressure, motor temperature, oil level (via capacitive sensor), and fault codes. Pfeiffer’s TPG300 series vacuum gauges and HiPace controllers can be daisy-chained into a unified control loop. Configuration and diagnostics are performed using Pfeiffer’s free VACUU®VIEW software (Windows-based), which logs timestamped operational parameters, enables trend analysis over 30+ days, and exports CSV-formatted datasets for traceability in ISO/IEC 17025-accredited labs.

Applications

• Physical vapor deposition (PVD) and sputtering systems requiring stable 10⁻³–10⁻⁴ mbar base pressures prior to plasma ignition.
• Vacuum heat treatment furnaces and brazing systems where rapid pump-down and minimal oil back-diffusion are essential for surface purity.
• Optical thin-film coating lines integrating multiple process chambers with shared vacuum manifolds.
• R&D vacuum systems in university and national laboratories conducting surface science, electron microscopy sample prep, and accelerator beamline conditioning.
• Vacuum drying and degassing of composites, ceramics, and battery electrode slurries under controlled low-pressure environments.

FAQ

What forepump options are certified for use with the WD series?
Pfeiffer specifies only DuoLine dual-stage rotary vane pumps (Duo 35, Duo 65, Duo 125, Duo 255) as factory-qualified forepumps—each rigorously tested for pressure staging, thermal coupling, and oil return suppression.
Is the WD series suitable for cleanroom installations?
Yes—when equipped with the standard oil mist filter and installed with ISO-KF or ISO-F flanged connections, the system meets ISO Class 5 particulate emission limits when operated within specified ambient temperature (15–35 °C) and humidity (<70% RH) ranges.
Can the WD pump handle water vapor loads during pump-down from atmosphere?
It can tolerate typical atmospheric moisture ingress during initial evacuation; however, sustained exposure to >70% RH environments or unvented humid loads requires supplemental water trap or refrigerated dryer integration upstream of the forepump.
What is the expected service interval for the magnetic coupling and rotors?
Under continuous operation at rated speed and ambient conditions, Pfeiffer specifies 12,000 operating hours for magnetic coupling integrity and 20,000 hours for rotor balance verification—both validated per DIN ISO 1940-1 G2.5 balancing grade.
Does the system include vacuum interlocks or safety cut-offs?
Standard configuration includes thermally activated motor overload protection, oil-level shutdown, and inlet overpressure bypass. Optional safety relays (EN 60204-1 compliant) and vacuum interlock inputs are available for integration into machine safety circuits.