DRETOP NEX Series Two-Stage and Single-Stage Oil-Lubricated Rotary Vane Vacuum Pumps

Overview

The DRETOP NEX Series comprises a comprehensive family of oil-lubricated rotary vane vacuum pumps engineered for reliable performance across medium-vacuum applications (10⁵ Pa to 1×10⁻² Pa). Based on the proven Couette flow principle in oil-sealed rotary vane architecture, these pumps generate vacuum through positive displacement via rotating vanes sliding within an eccentric stator chamber, with oil serving dual roles as sealing medium and lubricant. The NEX Series is specifically designed for continuous-duty operation in laboratories, R&D facilities, and industrial production environments—including semiconductor packaging, thin-film deposition, vacuum drying, solvent recovery, and vacuum impregnation. Its modular design supports standalone use or integration as a forepump for high-vacuum systems (e.g., diffusion pumps, turbomolecular pumps), enabling seamless vacuum staging from atmosphere to ultra-high vacuum regimes.

Key Features

• Robust Mechanical Architecture: Monoblock cylinder housing manufactured to ISO 2768-mK tolerances ensures dimensional stability under thermal cycling and mechanical load; validated vane geometry minimizes vibration and pressure pulsation for high reproducibility in process-critical applications.
• Intelligent Gas Ballast Control: Multi-position gas ballast valve enables precise adjustment of vapor handling capacity—optimized for water vapor, solvents, or mildly corrosive condensables without compromising ultimate pressure.
• Forced Lubrication System: Integrated gear-type oil pump and constant-pressure oil delivery mechanism maintain full hydrodynamic film thickness at inlet pressures up to 10 Torr (≈1330 Pa), preventing dry-start wear and extending bearing and vane service life.
• Dual-Stage Anti-Backstreaming Design: Two-stage models incorporate automatic oil-line shut-off valves and reverse-gas purge channels activated at shutdown—eliminating oil backstreaming into vacuum chambers with >99.9% efficacy per ASTM F2432-22 test protocol.
• Corrosion-Resistant Options (NEX-DF): NEX-DF variants feature 316L stainless steel springs, high-purity FKM seals, and electrophoretically deposited corrosion-inhibiting coatings on pump bodies—validated per ISO 9223 C3 classification for operation in weakly acidic (pH ≥3.5), oxidizing (e.g., O₃, H₂O₂), and humid environments.
• Air-Cooled Thermal Management: Optimized finned motor housings and axial airflow paths dissipate heat without external water circuits—supporting deployment in mobile labs, cleanrooms without chilled water infrastructure, or ISO Class 7/8 manufacturing zones.
• Integrated Oil Mist Filtration: High-efficiency coalescing filter (≤0.3 µm retention) reduces atmospheric oil mist emissions to <1 mg/m³—meeting EU Directive 2010/75/EU (IED) and US EPA AP-42 Section 10.2 requirements for stationary source VOC control.

Sample Compatibility & Compliance

The NEX Series accommodates diverse process gases including air, nitrogen, argon, water vapor, ethanol, acetone, and weakly aggressive mixtures (e.g., Cl₂ ≤100 ppm, SO₂ ≤50 ppm, O₃ ≤10 ppm). All models comply with IEC 61000-6-3 (EMC emission limits) and IEC 61000-6-2 (immunity). Electrical safety conforms to IEC 61000-3-2 (harmonic current limits) and UL 61010-1 (lab equipment). NEX-DF models are certified to IP54 (IEC 60529) for dust and splash resistance. Documentation includes full traceable calibration certificates (NIST-traceable pressure gauges), material declarations (RoHS 2011/65/EU, REACH SVHC), and conformity statements supporting GLP/GMP audit readiness.

Software & Data Management

While inherently analog-controlled, all NEX pumps integrate seamlessly with third-party PLCs and SCADA platforms via standard 4–20 mA analog outputs (vacuum level, motor temperature, oil level) and digital I/O (run/fault status, gas ballast position). Optional RS-485 Modbus RTU interface enables remote monitoring of operational parameters—including cumulative runtime, thermal history, and maintenance interval tracking—facilitating predictive maintenance aligned with ISO 13374-1 condition monitoring standards. Audit trails meet FDA 21 CFR Part 11 requirements when deployed with validated data acquisition software.

Applications

• Electronics Manufacturing: Forepumping for e-beam evaporators and sputtering systems; vacuum bake-out of PCBs and IC packages prior to hermetic sealing.
• Pharmaceutical Processing: Solvent recovery in API crystallization; vacuum tray drying of lyophilized intermediates per USP residual moisture specifications.
• Materials Science: Vacuum impregnation of carbon fiber preforms; degassing of ceramic slurries prior to slip casting; outgassing studies of aerospace composites under simulated space conditions.
• Environmental Testing: Supporting environmental chambers (ASTM D3574, ISO 188) for accelerated aging of elastomers and sealants under controlled vacuum-humidity cycles.
• Academic Research: Base pressure conditioning for surface science UHV chambers; vacuum distillation setups in organic synthesis labs; vacuum-assisted membrane filtration in bioseparations.

FAQ

What vacuum level can the NEX Series achieve with and without gas ballast?
With gas ballast open: ultimate total pressure ≤10 Pa (NEX single-stage) or ≤0.8 Pa (NEX two-stage); with gas ballast closed: ≤0.1 Pa (single-stage) or ≤5×10⁻² Pa (two-stage), measured per ISO 21360-1 using capacitance manometer calibration.
Can NEX pumps handle condensable vapors such as water or solvents?
Yes—gas ballast operation enables continuous removal of saturated vapors; recommended for water vapor loads ≤10 g/h and organic solvent loads ≤5 g/h at rated pumping speed.
Is oil change interval specified, and what oil grade is required?
Standard mineral oil (DRETOP VP-100, ISO VG 100) requires replacement every 3,000 operating hours or 12 months—whichever occurs first—per ISO 8573-1 Class 4 compressed air purity guidelines.
Do NEX-DF models support continuous operation in chlorine-containing atmospheres?
NEX-DF is rated for intermittent exposure to Cl₂ ≤100 ppm at 25°C; for sustained Cl₂ service >50 ppm or HF/HNO₃ presence, DRETOP dry screw pumps (e.g., DSX Series) are recommended.
Are mounting brackets and vibration isolation pads included?
All units ship with M6 threaded feet and rubber anti-vibration mounts compliant with ISO 10816-3 velocity thresholds (<2.8 mm/s RMS at 10–1000 Hz).