Pfeiffer Vacuum CombiLine WH Series Dry Roots Pumping System

Overview

The Pfeiffer Vacuum CombiLine WH Series is a modular, oil-free vacuum pumping system engineered for high-throughput industrial and advanced R&D applications requiring clean, reliable, and maintenance-optimized vacuum generation in the rough to medium vacuum range (10⁰ to 10⁻³ mbar). Based on the proven Couette-flow principle of dry Roots technology, the WH series integrates a high-speed Okta-series Roots booster pump with a robust dry screw base pump—either the UniDry S or HeptaDry P—forming a two-stage, fully dry vacuum solution. Unlike traditional oil-sealed systems, this configuration eliminates hydrocarbon backstreaming, vapor contamination, and oil degradation risks, making it especially suitable for processes where process purity, repeatability, and regulatory compliance are critical—such as thin-film deposition, vacuum metallurgy, photovoltaic cell manufacturing, and solvent-free drying.

Key Features

• Modular architecture enabling flexible configuration across 5 standard models (WH 240 S to WH 1800 P), each optimized for specific throughput and ultimate pressure requirements.
• Dry, oil-free operation throughout the entire pumping chain—no lubricating oil in either the Roots booster or the screw base pump—ensuring zero hydrocarbon contamination and eliminating oil disposal concerns.
• High volumetric efficiency: system pumping speeds range from 240 m³/h up to 1800 m³/h at 50 Hz, with optimized gas handling capacity for non-condensable and mildly condensable vapors.
• Ultimate system pressure down to < 2 × 10⁻³ mbar when paired with HeptaDry P-series base pumps; < 5 × 10⁻³ mbar with UniDry S-series—achievable without gas ballast or auxiliary foreline traps.
• Integrated thermal management and vibration-damped mechanical design ensure stable long-term operation under continuous duty cycles typical in production environments.
• Standard ISO-F inlet flanges (DN 63 to DN 160) allow direct integration into existing vacuum chambers, coating systems, or custom process lines without adapter complexity.

Sample Compatibility & Compliance

The WH Series is compatible with a wide range of process gases—including air, nitrogen, argon, oxygen, and low-concentration reactive mixtures—without performance degradation or material incompatibility. All wetted components utilize corrosion-resistant stainless steel (AISI 304/316) and PTFE-coated rotors, ensuring resilience against mild chemical exposure. The system conforms to EU Machinery Directive 2006/42/EC, Electromagnetic Compatibility Directive 2014/30/EU, and RoHS 2011/65/EU. Its construction and documentation support validation under GMP/GLP frameworks, and its oil-free nature facilitates alignment with FDA 21 CFR Part 11 data integrity expectations when integrated with compliant control software.

Software & Data Management

While the WH Series operates as a standalone hardware platform, it is fully compatible with Pfeiffer Vacuum’s HiPace Control and Vacuum Manager software suites via RS-485 or optional Ethernet interface. These tools enable real-time monitoring of motor current, bearing temperature, rotational speed, and system pressure trends. Audit trails, user-access levels, and event logging meet basic ALCOA+ principles for regulated environments. For integration into larger SCADA or MES platforms, Modbus TCP and OPC UA drivers are available through certified third-party middleware.

Applications

• Physical vapor deposition (PVD) and sputtering systems requiring high pumping speed and ultra-clean vacuum conditions.
• Vacuum heat treatment and brazing furnaces where oxidation-sensitive alloys demand hydrocarbon-free environments.
• Roll-to-roll and batch-type vacuum drying of pharmaceutical intermediates, battery electrode slurries, and polymer films.
• Outgassing and degassing stages in semiconductor packaging and MEMS fabrication lines.
• R&D vacuum chambers in university and national laboratories performing surface science, plasma physics, and materials synthesis experiments.
• Photovoltaic manufacturing—including CIGS and perovskite thin-film deposition—where residual oil traces would compromise layer adhesion and electrical homogeneity.

FAQ

Is the WH Series suitable for corrosive process gases?
The WH Series is designed for inert and mildly reactive gases. For highly corrosive media (e.g., Cl₂, HF, NH₃), optional Hastelloy rotor coatings or dedicated chemically resistant variants (e.g., WH-CR) must be specified at order stage.
What maintenance intervals are recommended for continuous 24/7 operation?
Under nominal load and ambient temperatures ≤35°C, scheduled inspection is recommended every 6,000 operating hours; full service—including rotor clearance verification and bearing replacement—is typically required after 12,000–18,000 hours, depending on gas load and particulate exposure.
Can the WH system be operated without a backing pump?
No. The Okta Roots booster requires a primary vacuum of ≤20 mbar to function; it must always be backed by a dry screw pump (UniDry or HeptaDry) or an equivalent oil-free forepump.
Does the WH Series comply with ISO 8573-1 Class 0 for compressed air purity?
Not applicable—the WH Series generates vacuum, not compressed air. However, its exhaust stream contains no oil aerosols or vapors, satisfying ISO 8573-1 Class 0 equivalency for hydrocarbon-free exhaust in facility ventilation contexts.
Is remote diagnostics supported out of the box?
Standard models include embedded serial diagnostics; remote access requires optional Ethernet module (part no. WH-ETH-01) and configuration via Pfeiffer’s Vacuum Manager Cloud Gateway (v3.2+).