The Great Wall SHB-III Desktop Circulating Water Vacuum Pump

Overview

The Great Wall SHB-III Desktop Circulating Water Vacuum Pump is an oil-free, water-jet-based vacuum generation system engineered for precision and reliability in academic and industrial laboratory environments. It operates on the principle of fluid ejector dynamics: pressurized circulating water passes through a converging-diverging nozzle (the jet ejector), inducing a pressure differential that draws ambient air or process gas into the suction chamber—thereby generating vacuum without mechanical compression stages or lubricating oils. This design eliminates hydrocarbon contamination risks, making it ideal for applications requiring clean vacuum conditions—including rotary evaporation, short-path distillation, vacuum filtration, freeze-drying pre-treatment, degassing of solvents, and crystallization under reduced pressure. Its compact desktop footprint and integrated 15 L water reservoir support continuous operation with minimal supervision, while the closed-loop water circulation conserves up to 95% of coolant versus once-through systems—aligning with ISO 50001-aligned lab energy management practices.

Key Features

• Oil-free, water-cooled vacuum generation: Eliminates risk of oil backstreaming, solvent contamination, or VOC adsorption—critical for analytical sample integrity and GLP-compliant workflows.
• Dual independent vacuum ports with individual gauges: Enables simultaneous operation of two vacuum-dependent instruments (e.g., one rotary evaporator + one vacuum oven) or parallel processing with isolated pressure control.
• Integrated anti-cavitation silencer: Reduces dissolved gas nucleation in circulating water, enhancing ultimate vacuum stability and lowering operational noise to ≤52 dB(A) at 1 m distance—meeting WHO occupational acoustic exposure guidelines.
• Corrosion-resistant wetted materials: Standard SHB-III configuration features 304 stainless steel pump body and impeller, PTFE-coated brass ejector nozzles, and fluororubber (FKM) shaft seals—ensuring compatibility with mildly acidic, basic, or polar organic vapors encountered in pharmaceutical synthesis and agrochemical R&D.
• Fail-safe liquid-backflow protection: Check valves installed in all internal gas pathways prevent reverse flow of water or condensate into connected apparatus during power interruption or sudden pressure equalization.
• Thermally stabilized motor assembly: 180 W induction motor with 304 SS shaft and IP20-rated enclosure ensures consistent torque delivery across ambient temperatures from 5–35 °C, supporting uninterrupted multi-hour operation under load.

Sample Compatibility & Compliance

The SHB-III is designed for use with non-aggressive, non-particulate-laden gases and vapors generated during standard laboratory unit operations. It is not rated for explosive, highly corrosive (e.g., HF, Cl₂), or particulate-laden streams. Compatible with ASTM D2879 (vacuum distillation), USP (aseptic processing support), and ISO 20347 (laboratory equipment safety). Meets IEC 61010-1:2010 requirements for electrical safety in laboratory equipment. Optional material variants (SHB-IIIA/IIIS/IIIG) allow selection of PP, PA66, or copper-PTFE components to match specific chemical exposure profiles—documentation supports material traceability per ISO 9001:2015 Clause 8.5.2.

Software & Data Management

The SHB-III is a standalone analog device with no embedded firmware or digital interface. All operational parameters—including vacuum level (via dual Bourdon tube gauges), flow status, and temperature-sensitive performance—are monitored manually. For labs implementing 21 CFR Part 11-compliant data governance, vacuum log entries may be recorded via external calibrated pressure transducers (e.g., Validyne DP15) connected to validated LIMS or ELN platforms. The pump’s stable baseline performance enables reproducible vacuum setpoints across batches—supporting audit-ready documentation under GMP Annex 11 and ISO/IEC 17025:2017 Clause 7.7.

Applications

• Routine solvent removal via rotary evaporation (R-210/R-300 series)
• Vacuum-assisted gravity filtration (Büchner funnels, fritted glass)
• Short-path and fractional distillation of heat-sensitive compounds
• Pre-concentration of biological extracts prior to HPLC analysis
• Deaeration of polymer precursor mixtures in materials science labs
• Support vacuum for lyophilizer shelf pre-cooling cycles
• Gas scavenging in Schlenk-line auxiliary systems

FAQ

What is the recommended water temperature range for optimal vacuum performance?
Maintain inlet water temperature between 10–25 °C; higher temperatures reduce vapor pressure margin and degrade ultimate vacuum. Use a recirculating chiller if ambient lab temperature exceeds 30 °C.
Can the SHB-III be used with organic solvents in the water reservoir?
No—only deionized or tap water is permitted. Solvent mixing risks pump cavitation, seal swelling, and gauge calibration drift.
Is routine maintenance required beyond water replacement?
Yes: inspect check valves quarterly for debris; clean ejector nozzles annually with 1% citric acid solution; verify gauge accuracy against a NIST-traceable reference every 12 months.
Does the pump meet CE or UL certification requirements?
It complies with GB 4706.1–2005 (Chinese national equivalent of IEC 60335-1) and carries CCC marking. CE/UL certification is available upon request for OEM integration projects.
How does the SHB-III compare to diaphragm vacuum pumps in terms of ultimate vacuum?
Diaphragm pumps typically achieve 5–10 mbar; the SHB-III reaches 20 mbar (0.098 MPa), sufficient for most evaporation and filtration tasks—but not high-vacuum applications such as mass spectrometry or electron microscopy.