HengAo HD Series Oil-Free Diaphragm Vacuum Pump

Overview

The HengAo HD Series Oil-Free Diaphragm Vacuum Pump is an engineered solution for laboratory-scale vacuum generation where oil contamination must be strictly avoided. Utilizing a positive-displacement diaphragm mechanism, this pump achieves stable vacuum levels through reciprocating motion of a reinforced elastomeric membrane—eliminating the need for lubricating oil and ensuring clean, particle-free vacuum environments essential for analytical sample preparation, solvent-sensitive applications, and regulated workflows. The HD series operates on a single- or dual-stage configuration, delivering ultimate vacuum pressures ranging from –0.08 MPa (single-stage) up to –0.1 MPa (dual-stage models), with continuous volumetric flow rates between 25 and 50 L/min at atmospheric inlet conditions. Its robust architecture supports sustained duty cycles in filtration, solid-phase extraction (SPE), vacuum drying, rotary evaporation support, and pressure-controlled concentration protocols—without risk of hydrocarbon carryover or membrane degradation from organic vapors.

Key Features

• Oil-free diaphragm technology ensures zero hydrocarbon contamination—critical for HPLC sample prep, mass spectrometry workflows, and pharmaceutical QA/QC labs.
• Reinforced 3-mm-thick diaphragm composed of oil-resistant synthetic rubber with embedded textile reinforcement layer, engineered for high-cycle fatigue resistance and extended service life (>10,000 hours under typical lab usage).
• Thermally optimized motor design (50–60 W) minimizes heat buildup during prolonged operation, maintaining consistent vacuum performance without thermal throttling.
• Modular pump head configurations: selectable single-stage (HD-25/HD-50) and dual-stage (HD-25A) variants for enhanced ultimate vacuum; optional flow regulation (HD-25D) via integrated needle valve for precision control over suction rate.
• Low-noise operation (<50 dB[A]) achieved through vibration-dampened housing, balanced crankshaft assembly, and acoustic insulation—suitable for shared lab spaces and ISO Class 5+ cleanroom-adjacent environments.
• Compact footprint and standardized mounting interface facilitate integration into fume hoods, vacuum manifolds, and automated sample processing platforms.

Sample Compatibility & Compliance

The HD Series is compatible with aqueous, polar organic, and mildly aggressive solvents (e.g., methanol, acetonitrile, ethyl acetate) when used with appropriate condensate traps and inline filters. It is not rated for halogenated solvents (e.g., chloroform, DCM) or strong oxidizers without additional chemical compatibility verification. From a regulatory standpoint, the pump’s oil-free construction aligns with USP Analytical Instrument Qualification requirements for Category B instruments, and its operational stability supports GLP-compliant documentation practices. While not inherently 21 CFR Part 11 compliant (as it lacks digital audit trail capability), its analog control interface permits integration with validated data acquisition systems meeting FDA and EMA electronic record standards.

Software & Data Management

The HD Series operates as a standalone analog instrument with manual pressure and flow adjustment. No embedded firmware or proprietary software is included; however, its electrical interface (standard IEC C14 input) enables seamless integration with third-party lab automation controllers (e.g., LabVIEW, Delta Tau PMAC, Beckhoff TwinCAT) via external pressure transducers and relay-based start/stop signaling. Optional analog output (0–5 V or 4–20 mA) can be added for real-time vacuum level monitoring in centralized SCADA or LIMS environments—supporting traceable process logging when paired with calibrated sensors and time-stamped acquisition hardware.

Applications

• Vacuum-assisted filtration of biological suspensions, cell lysates, and nanoparticle dispersions using PTFE, nylon, or PVDF membranes.
• Preparative solid-phase extraction (SPE) cartridge conditioning and elution across environmental, clinical, and forensic chemistry workflows.
• Support vacuum drying of hygroscopic compounds, lyophilized intermediates, and moisture-sensitive APIs under controlled temperature-vacuum profiles.
• Back-up vacuum source for rotary evaporators handling low-boiling-point solvents where oil diffusion pumps pose cross-contamination risks.
• Positive-pressure filtration assistance in sterile filtration setups requiring inert gas displacement and particulate-free vacuum integrity.

FAQ

What is the maximum continuous duty cycle for the HD-50 model?

The HD-50 is rated for uninterrupted operation up to 8 hours per session under ambient temperatures ≤30°C and relative humidity <70%, provided adequate ventilation and absence of liquid ingress.
Can the HD series be used with acidic vapors such as HCl or HF?

No. The standard diaphragm material is incompatible with strong mineral acids. For such applications, consult HengAo’s chemically resistant CR series with EPDM/FKM membrane options.
Is calibration certification available for purchase?

Yes—NIST-traceable vacuum calibration reports (per ISO 2533 and ASTM D2873) are available upon request, covering both ultimate vacuum and flow rate verification at 23°C ±2°C and 101.3 kPa.
Does the pump include an internal exhaust filter?

Standard units ship with a sintered metal inlet filter only; an optional activated carbon exhaust filter kit is available to adsorb volatile organics before atmospheric release.
What maintenance intervals are recommended?

Diaphragm inspection every 6 months or 2,000 operating hours; motor bearing lubrication is not required—the unit employs sealed, maintenance-free ball bearings.