CZGY SHJ-6AS Digital Constant-Temperature Magnetic Stirring Water Bath

Overview

The CZGY SHJ-6AS Digital Constant-Temperature Magnetic Stirring Water Bath is an integrated laboratory platform engineered for simultaneous precise temperature control and independent magnetic agitation across six parallel reaction vessels. Designed around Couette-type fluid dynamics principles, each of the six bath wells operates with a dedicated PID-controlled heating circuit and a sealed, brushless DC motor-driven magnetic stirrer—ensuring stable thermal equilibrium and consistent shear input without mechanical shaft penetration. The unit maintains setpoint accuracy within ±0.5°C over the full operational range (ambient +5°C to 100°C), validated per ASTM E1137/E1137M for liquid bath temperature uniformity. Its stainless-steel inner tank construction (304 grade) and electrophoretically coated cold-rolled steel outer housing provide long-term corrosion resistance in aqueous, mildly acidic, or basic environments typical of synthesis, dissolution testing, enzymatic assays, and stability studies.

Key Features

• Six independent, digitally controlled bath wells—each with real-time temperature display, adjustable timer (0–999 min), and individual on/off toggle
• Brushless DC stirring motors delivering 0–2000 rpm with ±1 rpm speed resolution and continuous digital RPM feedback
• High-integrity stainless-steel bath surface (fully welded, seamless cladding) for chemical inertness, easy decontamination, and compliance with GLP cleaning validation protocols
• Integrated drain ports on each module enable rapid, residue-free fluid exchange—critical for multi-step protocol transitions or cross-contamination prevention
• Modular support architecture: six standardized vertical support rods, six condenser clamps, and six 5-ring polypropylene covers included as standard—compatible with common 25–100 mL round-bottom flasks and reflux setups
• Electromagnetic interference (EMI)-shielded power distribution ensures stable operation in shared instrument labs with sensitive analytical equipment (e.g., HPLC, mass spectrometers)

Sample Compatibility & Compliance

The SHJ-6AS accommodates standard laboratory glassware including borosilicate round-bottom flasks (25–250 mL), volumetric flasks, and sample vials up to 13 cm height and 22 cm diameter. Each well’s φ22 cm × 13 cm cylindrical geometry supports immersion depth sufficient for effective heat transfer and vortex formation during stirring. The system complies with IEC 61010-1:2010 for electrical safety in laboratory equipment and meets CE marking requirements for electromagnetic compatibility (EN 61326-1). While not certified to ISO/IEC 17025, its temperature and speed traceability aligns with internal calibration procedures required under FDA 21 CFR Part 11 for electronic record integrity when paired with validated data logging software.

Software & Data Management

The SHJ-6AS operates as a standalone analog-digital hybrid instrument with no embedded microprocessor-based data logging. However, its RS-232 communication interface (optional accessory) enables integration with third-party LabVIEW™, MATLAB®, or custom Python-based acquisition systems for time-stamped recording of setpoints, actual temperatures, and RPM values. All timers and setpoints are retained through power cycling, supporting unattended overnight operation. For regulated environments, users may implement external audit-trail-capable data loggers compliant with 21 CFR Part 11 Annex 11 requirements—recording operator ID, parameter changes, and alarm events with cryptographic timestamping.

Applications

• Controlled-temperature dissolution testing per USP and Ph. Eur. 2.9.3, particularly for multi-sample comparative release profiling
• Enzyme kinetic studies requiring simultaneous incubation and mixing at physiological or elevated temperatures
• Organic synthesis workflows involving reflux, hydrolysis, or esterification across parallel reaction arrays
• Calibration of thermocouples, RTDs, and digital thermometers using NIST-traceable reference baths
• Preparation of homogeneous polymer solutions, nanoparticle dispersions, and colloidal suspensions prior to DLS or TEM analysis
• Stability-indicating assays under ICH Q1A(R2) conditions where thermal uniformity and mechanical consistency directly impact degradation pathway fidelity

FAQ

Can the SHJ-6AS be used for applications requiring temperature ramping?
No—the device provides only static setpoint control. Ramp-hold profiles require external programmable controllers interfaced via RS-232.
Is the stainless-steel bath surface suitable for use with strong oxidizers such as nitric acid?
304 stainless steel offers limited resistance to concentrated nitric acid above 20% w/w; use PTFE-coated stir bars and verify compatibility with material safety data sheets prior to exposure.
Does the unit include over-temperature protection?
Yes—each well features independent dual-limit thermal cutoffs (mechanical and electronic) that disable heating if temperature exceeds 105°C.
What is the recommended maintenance interval for the brushless motors?
No scheduled maintenance is required; brushless design eliminates commutator wear, with expected service life exceeding 20,000 operating hours under nominal load.
Can the ring covers be autoclaved?
The supplied polypropylene ring covers are autoclavable at 121°C, 15 psi for 20 minutes—verify seal integrity post-sterilization before reuse.