Xuxin Instrument ST-1504 Fully Automated Acid Number Analyzer
| Brand | Xuxin Instrument |
|---|---|
| Origin | Beijing, China |
| Manufacturer | Yes |
| Product Category | Domestic |
| Model | ST-1504 |
| Pricing | Upon Request |
Overview
The Xuxin Instrument ST-1504 Fully Automated Acid Number Analyzer is an electrometric titration system engineered for precise, reproducible determination of acid number (AN) in petroleum-based insulating oils—specifically transformer oil, turbine oil, and phosphate ester-based anti-wear hydraulic fluids. It operates on the principle of potentiometric endpoint detection in non-aqueous medium, implementing standardized neutralization titration with alcoholic potassium hydroxide (KOH) solution per ASTM D974, ISO 6618, and critically aligned with Chinese national standards GB/T 264 and GB/T 7599. The instrument automates the complete analytical workflow—including solvent extraction, sample homogenization, reagent delivery, dynamic stirring, real-time pH monitoring, endpoint recognition, and result calculation—eliminating manual intervention and operator-induced variability. Designed for routine QC laboratories in power generation, petrochemical refining, and lubricant R&D facilities, the ST-1504 delivers trace-level sensitivity (0.001 mg KOH/g) and robust inter-batch repeatability (<3% RSD), meeting GLP-compliant documentation requirements for audit-ready data integrity.
Key Features
- Automated dual-channel peristaltic pumping system (imported high-precision tubing) for independent, volumetrically accurate delivery of extraction solvent (e.g., toluene–isopropanol–water mixture) and titrant (0.01–0.1 mol/L KOH in 2-propanol), minimizing carryover and ensuring ±0.5% volumetric accuracy across 0.1–10 mL dispense ranges.
- Integrated photometric endpoint detection module with dual-wavelength optical compensation, enabling automatic baseline correction and drift compensation during titration—critical for dark or oxidized oil matrices where colorimetric indicators are unreliable.
- Modular sample carousel accommodating either 3 or 6 standard 50-mL glass vials; each position features motorized indexing, thermal stabilization plate (ambient-only operation), and RFID-assisted sample tracking for unattended batch processing.
- 7-inch full-color capacitive touchscreen interface supporting both fully localized Chinese and English language modes; firmware includes embedded calibration wizards, user-level access control (admin/operator/guest), and configurable method templates for multi-standard compliance.
- Onboard thermal-line printer (high-speed micro-thermal technology) generating tamper-evident reports with embedded timestamp (YYYY-MM-DD HH:MM:SS), sample ID, method ID, raw titration curve snapshot, and final AN value with uncertainty annotation.
- Non-volatile memory storage for up to 500 test records, each retaining full metadata: operator ID, environmental conditions (T/ RH logged at start), reagent lot numbers, calibration history, and raw sensor voltage vs. volume curves.
Sample Compatibility & Compliance
The ST-1504 is validated for use with mineral-based, synthetic, and ester-based insulating oils conforming to IEC 60296, ASTM D3487, and GB/T 7595 specifications. It supports direct analysis of undiluted samples (no pre-dilution required for AN ≤ 1.000 mg KOH/g) and accommodates viscosity ranges up to 100 cSt at 40 °C. All hardware and software components comply with electromagnetic compatibility (EMC) per IEC 61326-1 and electrical safety per IEC 61010-1. Data management architecture supports 21 CFR Part 11 readiness via optional audit trail module (user action logging, electronic signature integration, and immutable record archiving). Method validation documentation—including precision, accuracy, LOD/LOQ, and ruggedness studies per ICH Q2(R2)—is available upon request for regulatory submission support.
Software & Data Management
The embedded firmware (v3.2+) implements a deterministic state-machine controller with fail-safe error handling: automatic abort on abnormal pH slope, insufficient sample volume detection, or pump occlusion. Raw data export is supported via USB 2.0 (CSV/Excel-compatible format) including time-stamped titration curves (mV vs. mL), derivative plots (dE/dV), and calculated equivalence points. Optional PC-based XuxinLab Suite (Windows 10/11 compatible) enables remote instrument control, multi-instrument fleet monitoring, statistical process control (SPC) charting, and LIMS integration via ASTM E1384-compliant HL7 messaging. All data files include SHA-256 checksums and digital watermarks for forensic traceability.
Applications
- Condition monitoring of transformer oil in substation asset management programs (IEC 60429 trending)
- Acceptance testing of new turbine oils prior to commissioning (ASTM D4378 compliance)
- Accelerated oxidation stability assessment (RBOT/DSC correlation studies)
- Quality release testing of phosphate ester fire-resistant fluids in aviation hydraulics
- Acid number profiling during lubricant formulation development and additive package optimization
- Educational laboratory instruction for ASTM/ISO titration methodology and electrochemical sensor principles
FAQ
What standards does the ST-1504 natively support?
It is factory-configured for GB/T 264 and GB/T 7599, with method templates pre-loaded for ASTM D974, ASTM D664, and ISO 6618.
Can the instrument be calibrated and certified by a national metrology institute?
Yes—Xuxin Instrument provides optional NIM (National Institute of Metrology, China) traceable calibration certificates (CNAS-accredited) for acid number measurement, covering volumetric delivery, electrode response, and temperature compensation modules.
Is the system compatible with LIMS or enterprise QA databases?
Via optional XuxinLab Suite, it supports ASTM E1384, ASTM E1467, and custom CSV/JSON API endpoints for seamless bidirectional data exchange.
What maintenance intervals are recommended for long-term operational reliability?
Peristaltic pump tubing should be replaced every 6 months under continuous use; pH electrode recalibration is advised before each batch, and full system verification (using certified reference oil SRM 2720a) is recommended quarterly.
Does the analyzer require inert gas purging or moisture exclusion during operation?
No—the sealed titration cell and solvent delivery path incorporate desiccant traps and positive-pressure nitrogen blanket option (accessory) for ultra-low AN measurements (<0.01 mg KOH/g), though ambient operation meets all stated specifications.
