Yiheng BP-150 High-Precision Refrigerated & Heated Circulating Bath for Viscometers

Overview

The Yiheng BP-150 is a high-precision refrigerated and heated circulating bath engineered specifically for viscometry applications requiring stringent thermal control. It operates on a dual-mode thermoregulation principle—integrating a high-efficiency hermetic compressor for active cooling and SUS304 stainless-steel immersion heaters for precise heating—enabling stable operation across a broad temperature range from −10 °C to 100 °C. Its core function is to deliver a uniform, vibration-minimized thermal environment to external viscometers (e.g., rotational, capillary, or falling-ball types) via an externally connected fluid loop, while also supporting direct immersion of standard 500 mL beakers containing sample solutions. The system employs digital PID feedback control with real-time sensor monitoring, ensuring thermal stability within ±0.02 °C—critical for ASTM D2983, ISO 2555, and USP viscosity measurements where temperature deviation directly impacts shear-rate-dependent viscosity values.

Key Features

• Dual-mode thermal regulation: Independent refrigeration and heating circuits enable seamless transition between sub-zero and boiling-point conditions without thermal overshoot.
• High-stability circulation pump: Pressure-suction design supports both internal recirculation (for bath homogeneity) and external flow (up to 15 L/min at 0.3 bar), compatible with viscometer jacket inlets and outlet manifolds.
• SUS304 stainless-steel wetted components: Includes heater elements, pump housing, and bath chamber—ensuring corrosion resistance against water, ethylene glycol/water mixtures, silicone oils, and other common bath media.
• Intelligent controller interface: 4.3-inch TFT LCD display with menu-driven navigation; supports real-time monitoring of setpoint, actual bath temperature, pump status, and system alarms.
• Comprehensive safety architecture: Dual independent overtemperature cutoffs (electronic + mechanical), dry-run protection, compressor delay start (≥3 min), and integrated RCD/GFCI-rated power module compliant with IEC 61010-1.
• Maintenance-optimized design: Removable front air-intake grille facilitates routine condenser cleaning; bottom-mounted drain valve enables full bath fluid evacuation without disassembly.

Sample Compatibility & Compliance

The BP-150 accommodates standard laboratory viscometry configurations—including Brookfield, Anton Paar, and Thermo Scientific viscometers—via standardized ¼″ NPT or M12 quick-connect ports. Its 7 L working volume permits direct placement of 500 mL glass beakers, enabling rapid method transfer between benchtop rheometers and rotational viscometers. The unit meets CE marking requirements under the Low Voltage Directive (2014/35/EU) and Electromagnetic Compatibility Directive (2014/30/EU). For regulated environments, its optional RS232 or USB data export supports audit-ready traceability when paired with validated third-party logging software—aligning with GLP documentation practices and FDA 21 CFR Part 11 data integrity expectations where electronic records are archived.

Software & Data Management

The BP-150 offers two mutually exclusive digital interface options: RS232 serial output (compatible with legacy lab printers and SCADA systems) or USB mass-storage mode (for time-stamped CSV log files stored on removable flash drives). Neither interface provides real-time remote control; instead, they serve as passive data sinks for temperature history, alarm events, and operational timestamps. The built-in multi-segment programmable controller stores up to seven user-defined profiles, each comprising nine sequential steps (ramp rate, hold time, target temperature)—ideal for simulating temperature-dependent viscosity sweeps per ISO 6721-1 or ASTM D445 protocols. All logged data retain millisecond-level timestamp resolution and are uneditable post-generation, supporting raw-data review during quality audits.

Applications

• Temperature-controlled viscosity profiling of polymer melts, lubricants, pharmaceutical suspensions, and food emulsions.
• Calibration support for capillary viscometers (e.g., Ubbelohde, Cannon-Fenske) requiring ISO 3104-compliant thermal conditioning.
• Thermal pre-conditioning of samples prior to rheological testing on controlled-strain instruments.
• Stabilization of optical cells in refractometry or polarimetry setups sensitive to thermal drift.
• General-purpose temperature maintenance for enzymatic assays, dissolution testing baths, and chromatography column ovens.

FAQ

What bath fluids are compatible with the BP-150?

Deionized water, 30–50% aqueous ethylene glycol solutions, and low-viscosity silicone oils (up to 100 cSt) are approved. Avoid halogenated solvents, strong acids/bases, or fluids with flash points below 60 °C.
Can the BP-150 maintain temperature stability during continuous external flow?

Yes—its pressure-suction pump and oversized heat exchanger ensure ±0.02 °C stability even at maximum external flow rates (≤15 L/min), provided the connected instrument’s thermal load remains within 800 W.
Is the unit suitable for GMP-regulated laboratories?

While the BP-150 itself is not 21 CFR Part 11–validated out-of-the-box, its deterministic logging behavior, non-volatile memory, and tamper-evident file structure enable qualification as a Class II ancillary device under Annex 11 when deployed with documented IQ/OQ protocols.
Does the system support remote monitoring via Ethernet or Wi-Fi?

No—only RS232 and USB interfaces are available. Network connectivity requires external serial-to-Ethernet converters, which fall outside factory validation scope.
What is the expected service life of the compressor under continuous operation?

Rated for ≥25,000 hours MTBF when operated within ambient temperatures of 15–30 °C and maintained per scheduled condenser cleaning intervals (every 6 months under typical lab use).