Chengmengweiye CM-24A Manual-Adjustable 24-Position Water Bath Nitrogen Evaporator

Overview

The Chengmengweiye CM-24A is a manually operated, 24-position water bath nitrogen evaporator engineered for precise, reproducible solvent removal in analytical laboratories. It operates on the principle of gentle inert gas (nitrogen) displacement—directing a controlled stream of nitrogen across the surface of heated liquid samples to accelerate evaporation without thermal degradation. Unlike dry-block or air-heated systems, the CM-24A employs a thermostatically regulated circular stainless steel water bath, ensuring uniform heat distribution and minimizing temperature gradients across all 24 sample positions. This design is particularly suited for thermally labile analytes in environmental, pharmaceutical, food safety, and clinical applications where consistent endpoint control and low cross-contamination risk are critical. The instrument is not automated but provides full manual adjustability of both sample height and gas delivery depth—enabling method optimization for diverse vessel geometries (e.g., test tubes, centrifuge tubes, conical vials) and solvent volumes (1–50 mL).

Key Features

• Manually adjustable sample rack with 24 individually numbered positions; each accommodates tubes from 10 mm to 29 mm in diameter via spring-loaded clamps and a supporting disc.
• Independent vertical adjustment of each nitrogen delivery needle (0–150 mm travel), allowing precise positioning just above the meniscus for optimal evaporation efficiency and minimal splashing.
• Stainless steel construction throughout—including bath chamber, support frame, gas manifold, and needle guide system—ensuring resistance to corrosion from organic solvents, acids, and bases.
• Digital PID temperature controller with dual LED display (setpoint and actual bath temperature), ±0.1°C resolution, over-temperature alarm, and dry-run protection.
• Integrated gas flow regulation: each position features an imported precision needle valve for independent control of nitrogen flow (0–15 L/min total, ~330 mL/min per channel at typical settings).
• Water bath temperature range: ambient +5°C to 99°C (standard); optional methyl silicone oil medium extends operational range up to 150°C upon customization.
• Timed operation capability (0–99 h 59 min) with audible end-of-cycle alert; compatible with GLP-compliant documentation when paired with external logging devices.

Sample Compatibility & Compliance

The CM-24A supports standard laboratory glassware including round-bottom test tubes (10–29 mm OD), 15 mL and 50 mL centrifuge tubes, and small conical vials. Its mechanical design allows secure mounting without adapters for most common formats. While the unit itself does not carry CE, UL, or FDA certification, its materials and functional architecture align with general laboratory safety requirements for use inside certified fume hoods—especially during evaporation of volatile or toxic solvents (e.g., hexane, chloroform, ethyl acetate). All wetted components comply with ISO 8573-1 (compressed air purity classes) when used with filtered, oil-free nitrogen supply. The device meets basic electrical safety standards per GB 4793.1–2007 (Chinese equivalent of IEC 61010-1) and is suitable for environments operating under ISO/IEC 17025 or cGMP-aligned quality systems when validated per internal SOPs.

Software & Data Management

The CM-24A is a standalone benchtop instrument with no embedded software or network connectivity. Temperature setpoints, timer values, and gas flow adjustments are performed locally via tactile controls and digital displays. For traceability, users may record operational parameters (start time, final temperature, duration, gas pressure) manually or integrate the unit into a broader LIMS or ELN workflow using external data loggers (e.g., RS-232 or analog 4–20 mA output modules available upon request). Though not natively 21 CFR Part 11 compliant, audit trails can be established through procedural controls—such as operator sign-off logs, calibration records for the digital thermostat (traceable to NIST-certified references), and periodic verification of temperature uniformity (≤ ±1.0°C at 60°C per ISO 17025 clause 5.10.4).

Applications

• Residue analysis: Pesticide and herbicide extraction from fruits, vegetables, grains, and plant tissues (aligned with AOAC 2007.01 and EPA Method 525.3).
• Pharmaceutical QC: Concentration of extracts prior to HPLC or GC-MS analysis in traditional Chinese medicine testing and stability studies.
• Environmental monitoring: Pre-concentration of trace-level PAHs, PCBs, and organochlorines from drinking water, wastewater, and soil leachates (per ASTM D5847 and ISO 10304-1).
• Clinical toxicology: Preparation of biological matrices (serum, plasma, urine) for LC-MS/MS quantification of drugs of abuse and metabolites.
• Food safety: Detection of dioxins, furans, and mycotoxins in dairy products, alcoholic beverages, and liquid foods following QuEChERS-based cleanup.

FAQ

Is the CM-24A compatible with non-aqueous heating media such as silicone oil?
Yes—the water bath chamber accepts methyl silicone oil for extended temperature operation up to 150°C; users must verify viscosity and flash point compatibility with their specific oil grade.
Can individual needle heights be locked after adjustment?
Yes—each stainless steel needle assembly includes a knurled locking collar that secures vertical position once optimized for a given tube height and solvent volume.
What is the recommended nitrogen supply pressure?
Optimal inlet pressure is 0.1–0.2 MPa; higher pressures may cause turbulence or splashing unless flow valves are carefully calibrated.
Does the unit include a drain valve for the water bath?
No—drainage requires manual siphoning or tilting; optional bottom-mounted drain kits are available as accessories.
How often should the temperature sensor be calibrated?
We recommend quarterly verification against a NIST-traceable thermometer, especially before high-precision quantitative workflows.