LT Series Circulating Chillers
| Brand | The Great Wall |
|---|---|
| Origin | Henan, China |
| Manufacturer Type | OEM Manufacturer |
| Country of Origin | China |
| Model | LT-100-80 |
| Pricing | Upon Request |
Overview
The LT Series Circulating Chillers are precision-engineered low-temperature thermal management systems designed to deliver stable, controllable cryogenic cooling for laboratory and pilot-scale process applications. Based on vapor-compression refrigeration architecture with dual-stage cascade compression, these chillers achieve sustained operating temperatures as low as –100 °C at the heat exchange interface—enabling precise thermal control of reaction vessels, material testing platforms, and simulation environments. Unlike open-bath coolants or dry-ice-based solutions, the LT Series employs a fully sealed, closed-loop circulation system using specialized low-freezing-point heat transfer fluids (e.g., ethanol/water or silicone oil blends), minimizing evaporation loss, moisture ingress, and fluid degradation over extended operation cycles. This architecture ensures long-term thermal stability, reproducible temperature setpoints, and compatibility with sensitive analytical workflows in regulated environments.
Key Features
- Fully hermetic circulation design prevents volatile loss and hygroscopic contamination of heat transfer fluid, extending service life and reducing maintenance frequency.
- Dual-stage cascade refrigeration system enables reliable operation down to –100 °C without liquid nitrogen dependency.
- Comprehensive electrical and mechanical protection suite: high-pressure cut-off, phase-sequence monitoring, compressor delay start (≥3 min), thermal overload relay, and overcurrent interruption.
- Automatic overfill safety mechanism: integrated level sensor triggers controlled fluid discharge when fill volume exceeds nominal capacity—preventing pump cavitation and seal damage.
- Stainless steel reservoir and fluid path construction resists corrosion from aggressive solvents and low-temperature embrittlement.
- Front-panel digital controller with PID tuning capability, real-time temperature logging (optional), and ±0.3 °C temperature stability at setpoint (load-dependent).
Sample Compatibility & Compliance
The LT Series is engineered for integration with jacketed reactors (glass and stainless steel), calorimeters, rheometers, and environmental test chambers requiring sub-ambient thermal conditioning. Its closed-loop architecture eliminates cross-contamination risk between coolant and process media—critical for GMP-compliant pharmaceutical synthesis and ISO 17025-accredited materials testing labs. While not certified to UL/CSA or CE for standalone safety compliance, the units conform to IEC 61000-6-3 (EMC emissions) and IEC 61000-6-2 (immunity) standards. When deployed within validated processes, they support adherence to FDA 21 CFR Part 11 (with optional audit-trail-enabled software), USP (Thermal Analysis), and ASTM E2496 (Low-Temperature Reaction Calorimetry) requirements.
Software & Data Management
Standard configuration includes an embedded microcontroller with RS485 Modbus RTU interface for PLC or SCADA integration. Optional Ethernet-enabled firmware supports remote monitoring via web browser or third-party LabVIEW/Python APIs. Temperature profiles, alarm logs, and runtime statistics are timestamped and exportable as CSV. For regulated environments, the optional Data Integrity Package provides electronic signatures, user access levels (admin/operator), and immutable audit trails compliant with ALCOA+ principles—facilitating GLP/GMP documentation and internal quality audits.
Applications
- Controlled low-temperature synthesis in API manufacturing (e.g., lithiation, Grignard, cryogenic hydrogenation).
- Thermal cycling validation of polymer composites and battery electrolytes under ASTM D696 and IEC 62660-2 protocols.
- Calibration and performance verification of differential scanning calorimeters (DSC) and thermogravimetric analyzers (TGA).
- Stabilization of laser sources, CCD detectors, and superconducting magnet cooling circuits in physics research facilities.
- Simulated seasonal aging tests for automotive adhesives and aerospace sealants per SAE J2527 and ISO 4892-2.
FAQ
What is the lowest achievable bath temperature with the LT-100-80 model?
The LT-100-80 maintains a stable setpoint of –100 °C at the chiller outlet under nominal load conditions (≤1.5 kW heat load, ambient ≤25 °C). Actual process temperature depends on heat exchanger efficiency and insulation integrity.
Is the unit compatible with flammable heat transfer fluids?
No. Only non-flammable, low-volatility fluids meeting ISO 6743-22 Class HEES or HETG specifications are approved. Use of ethanol/water mixtures requires additional ventilation and explosion-proof electrical upgrades.
Can the chiller be integrated into a distributed control system (DCS)?
Yes—via standard Modbus RTU over RS485. Optional Profibus DP and EtherNet/IP gateways are available upon request.
Does the system include flow rate monitoring?
Standard models feature a calibrated flow switch with dry-contact alarm output. Optional ultrasonic flow metering (0.5–10 L/min range, ±2% FS accuracy) is available with analog 4–20 mA output.
What maintenance intervals are recommended?
Compressor oil and filter replacement every 12 months or 4,000 operating hours; refrigerant leak check annually; heat exchanger cleaning biannually in hard-water regions.
