Shanghai Xufeng KV-L12 Low-Temperature Kinematic Viscosity Constant-Temperature Bath

Overview

The Shanghai Xufeng KV-L12 Low-Temperature Kinematic Viscosity Constant-Temperature Bath is a precision-engineered thermal control system designed exclusively for kinematic viscosity measurements of petroleum products and other Newtonian liquids in accordance with internationally recognized standards—including GB/T 265, ASTM D445, ISO 3104, and IP 71. It provides a thermally stable, highly uniform bath environment essential for capillary viscometry, where temperature deviation directly impacts measurement accuracy per the fundamental relationship ν = t × C (where ν is kinematic viscosity, t is efflux time, and C is the viscometer constant). The KV-L12 achieves ±0.02 °C temperature uniformity and stability across its working volume—critical for meeting the ≤±0.03 °C requirement specified in ASTM D445 Annex A1 for high-accuracy testing. Its modular architecture supports integration with optional external refrigeration units (40RC or 60RC), extending operational range from −60 °C to +100 °C—enabling low-temperature characterization of diesel fuels, lubricants, base oils, and aviation turbine fuels under winter-grade specifications.

Key Features

• High-stability dual-loop PID temperature control using Pt100 platinum resistance sensors and solid-state relays, delivering real-time regulation with 0.01 °C display resolution and ±0.02 °C setpoint accuracy.
• Integrated VFD fluorescent display showing simultaneous readouts of setpoint, actual bath temperature, two independent efflux timers (0.001 s resolution), test date/time, and diagnostic status.
• Dual test ports with interchangeable viscometer holders—compatible with standard Ubbelohde, Cannon-Fenske, and suspended-level (Ostwald-type) capillary viscometers per user specification.
• Internal circulation via a sealed magnetic-drive pump (1.9 L/min flow, 3 m head) ensuring laminar, vibration-free fluid motion and eliminating contamination risk from mechanical seals.
• Side-mounted fluorescent illumination behind borosilicate glass bath cylinder for glare-free visual monitoring of capillary flow without thermal interference.
• Comprehensive data integrity features: 99-test non-volatile memory storage (date, temperature, timer values, channel assignment); nine-point temperature calibration correction; automatic fault detection (sensor open-circuit, low fluid level) with audible alarm and on-screen error code.
• Optional auto-print functionality via RS232 interface for GLP-compliant hardcopy record generation when paired with a serial thermal printer.

Sample Compatibility & Compliance

The KV-L12 is validated for use with transparent and opaque Newtonian petroleum liquids—including crude oil fractions, mineral oils, synthetic lubricants, jet fuels (Jet A-1, JP-8), and biodiesel blends—as defined in ASTM D445 and ISO 3104. It supports both single- and dual-capillary configurations, accommodating viscometers calibrated per ASTM D2161 or ISO 3105 traceable to NIST SRMs. The bath’s cylindrical Dewar geometry (Ø190 × 270 mm) ensures minimal thermal stratification, satisfying the “uniform temperature zone” requirement of ISO 3104 Clause 6.2. When operated with external cryogenic chillers (40RC or 60RC), it meets ASTM D7153 (low-temperature kinematic viscosity of diesel fuel oils) and ASTM D4052 (density and kinematic viscosity of petroleum products by digital density meter—where bath-controlled sample equilibration is required).

Software & Data Management

While the KV-L12 operates as a standalone hardware platform with embedded microcontroller firmware, its data output structure aligns with common laboratory informatics requirements. All stored test records—including timestamp, set temperature, actual bath temperature (averaged over 30 s), two efflux times, and user-assigned test ID—are retrievable via front-panel navigation or exported via RS232 for import into LIMS or Excel-based QA databases. The nine-point temperature calibration function allows traceable offset correction at defined reference points (e.g., 0 °C, 25 °C, 40 °C, 100 °C), supporting internal audit readiness under ISO/IEC 17025 Clause 6.4.2 and FDA 21 CFR Part 11–aligned procedural controls when combined with documented SOPs and electronic signature protocols.

Applications

• Quality control of finished lubricants and base stocks per ASTM D445 and GB/T 265.
• Low-temperature performance evaluation of automotive engine oils (SAE J300), gear oils, and hydraulic fluids.
• Specification conformance testing for aviation turbine fuels (ASTM D1655 Annex A2) and marine distillate fuels (ISO 8217).
• Research-grade viscosity-temperature profiling (VTF) for formulation development and additive interaction studies.
• Calibration and verification of capillary viscometers in metrology laboratories accredited to ISO/IEC 17025.
• Supporting dynamic viscosity derivation (η = ν × ρ) when paired with digital densitometers compliant with ASTM D4052.

FAQ

What external chillers are compatible with the KV-L12?
The KV-L12 is designed for seamless integration with the Shanghai Xufeng 40RC (−40 °C minimum) and 60RC (−60 °C minimum) recirculating chillers. Both units connect via standardized quick-coupling fittings and share synchronized communication for coordinated temperature ramping and safety interlock.
Can the KV-L12 operate without an external chiller?
Yes—the base unit functions independently as a high-precision ambient-to-100 °C constant-temperature bath, equivalent in specification to the KV-4 model, and is fully compliant with ASTM D445 for routine room-temperature and elevated-temperature testing.
Is the bath suitable for non-petroleum Newtonian fluids?
Yes—provided the fluid is chemically compatible with borosilicate glass and stainless-steel wetted parts, and exhibits Newtonian behavior within the intended shear-rate regime of capillary viscometry.
How is temperature uniformity verified during qualification?
Per ISO/IEC 17025 and ASTM E1137, uniformity is assessed using three calibrated Pt100 probes placed at center, upper quadrant, and lower quadrant positions within the bath volume while stabilized at target temperatures (e.g., −20 °C, 40 °C, 80 °C); deviations must remain within ±0.02 °C.
Does the instrument support 21 CFR Part 11 compliance?
The KV-L12 itself does not include electronic signature or audit-trail modules; however, its deterministic data output, calibration traceability, and configurable print/export functions enable integration into Part 11–compliant workflows when deployed within validated software environments and procedural controls.