Yiheng BSH-3A Circulating Water Vacuum Pump

Overview

The Yiheng BSH-3A Circulating Water Vacuum Pump is a water-sealed, oil-free vacuum source engineered for stable, low-maintenance operation in academic, pharmaceutical, biochemical, food science, and agricultural engineering laboratories. Unlike mechanical or diaphragm vacuum pumps, it operates on the principle of water-ring vacuum generation: rotating water within the pump chamber creates sealed cavities that expand and contract to draw gas from connected apparatus, compress it, and discharge it through the exhaust port. This design eliminates the need for lubricating oil—avoiding contamination risks in sensitive applications such as solvent distillation, rotary evaporation, vacuum filtration, freeze-drying, and degassing of aqueous or organic solutions. With an ultimate vacuum of –0.098 MPa (2 kPa absolute), the BSH-3A delivers sufficient negative pressure for most routine lab-scale vacuum processes while maintaining thermal stability and chemical inertness across extended duty cycles.

Key Features

• Dual independent vacuum heads with individual pressure gauges—enabling simultaneous or isolated operation of two experimental setups without cross-contamination or pressure interference.
• Integrated fluid-damped silencer system that minimizes turbulence-induced noise and suppresses dissolved gas release from circulating water, resulting in improved vacuum stability and reduced operational sound levels (<55 dB(A) at 1 m).
• Chemically resistant polypropylene (PP) water reservoir (15 L capacity) with corrosion-proof internal components—including fluororubber shaft seals and acid/alkali/solvent-tolerant wetted surfaces—ensuring long-term reliability when handling aggressive reagents such as HCl, NaOH, acetone, or ethanol.
• Energy-efficient 180 W induction motor supplied by a certified industrial motor manufacturer; achieves >35% lower power consumption compared to equivalent single-stage rotary vane pumps under comparable vacuum load conditions.
• Automatic check valve prevents backflow of water into evacuated systems during power interruption or shutdown—protecting glassware, condensers, and sample integrity.
• Compact footprint (385 × 280 × 420 mm) and lightweight construction (11 kg) facilitate benchtop integration and mobility between fume hoods, glove boxes, or shared instrumentation labs.

Sample Compatibility & Compliance

The BSH-3A is compatible with standard laboratory vacuum interfaces (e.g., 10–19 mm hose barbs, ISO-KF 16/25 flanges via optional adapters) and supports continuous operation with water recirculation—eliminating wastewater discharge and reducing environmental impact. Its oil-free, water-sealed architecture complies with ISO 8573-1 Class 0 air purity requirements for non-contaminating vacuum sources. While not certified to GLP or GMP standards per se, its design supports audit-ready workflows: consistent vacuum output enables reproducible process parameters in methods aligned with ASTM E2912 (Standard Guide for Vacuum Drying of Pharmaceuticals) and USP (Sterile Preparation). The absence of hydrocarbon vapors makes it suitable for use upstream of mass spectrometers or residual gas analyzers where background interference must be minimized.

Software & Data Management

The BSH-3A is a manually operated, analog-control device with no embedded microprocessor or digital interface. It features dual analog vacuum gauges calibrated to –0.1 MPa range and requires no firmware, drivers, or software installation. For laboratories implementing electronic lab notebooks (ELN) or LIMS, vacuum status can be logged manually or integrated via external pressure transducers (e.g., Validated Honeywell PX2EF series) paired with USB data loggers compliant with FDA 21 CFR Part 11 for audit-trail-capable recordkeeping. Optional temperature sensors (PT100) may be installed in the water tank to monitor thermal drift during prolonged operation.

Applications

• Vacuum-assisted rotary evaporation of heat-sensitive compounds in natural product isolation and synthetic chemistry.
• Multi-port vacuum filtration using Buchner funnels or membrane filter holders in microbiology and environmental sample processing.
• Controlled drying of hygroscopic solids and crystalline intermediates under reduced pressure per ICH Q5C guidelines.
• Deaeration of polymer precursor solutions prior to casting or electrospinning.
• Supporting cold trap configurations in fractional distillation setups to prevent solvent vapor ingress into secondary condensers.
• Providing stable suction for aspiration manifolds in cell culture hoods and tissue dissociation workflows.

FAQ

Is the BSH-3A suitable for vacuum oven applications?

Yes—when used with appropriate thermal insulation and pressure-rated tubing, it maintains stable vacuum down to 2 kPa for ovens operating up to 80 °C. Continuous water circulation prevents overheating of the pump casing.
Can tap water be used continuously, or is deionized water required?

Tap water is acceptable for general use; however, hard water may cause scale buildup over time. For >200 hours/year operation, softened or deionized water is recommended to extend service intervals.
What maintenance is required?

Monthly visual inspection of water level and seal integrity; biannual cleaning of the impeller chamber with dilute citric acid solution to remove mineral deposits; annual replacement of the fluororubber shaft seal if operating >500 hr/year.
Does the pump include overload protection?

Yes—the motor incorporates thermal cut-off protection rated to 130 °C, automatically disabling power until cooldown.
Can the BSH-3A be mounted vertically or in enclosed cabinets?

No—it must be operated horizontally on a level surface with ≥50 mm clearance around all sides for convective cooling and water reservoir venting.