Koehler FK35100 Corrosion and Oxidation Stability Tester

Overview

The Koehler FK35100 Corrosion and Oxidation Stability Tester is a precision-engineered laboratory instrument designed to evaluate the oxidative degradation behavior and corrosive potential of lubricating oils under accelerated, controlled thermal-oxidative stress. It operates on the principle of forced-air oxidation in the presence of catalytic copper wire or other standardized metal coupons, simulating long-term service conditions in hydraulic systems, aviation turbine engines, and high-performance industrial gear oils. The system subjects six oil samples simultaneously to elevated temperatures (up to 399 °C), regulated airflow, and defined exposure durations—enabling quantitative assessment of acid number increase, sludge formation, viscosity change, and copper strip corrosion per internationally recognized test protocols.

Key Features

• Simultaneous testing of six independent samples with individual sample wells and uniform thermal distribution across the heated block.
• Microprocessor-based PID temperature control delivering rapid thermal equilibration and exceptional stability (±0.5 °C) across the full operating range (51.7–399 °C).
• Dual-mode digital display showing both setpoint and real-time temperature in selectable °C or °F units for operator clarity and traceability.
• Independent mass flow control for each test position via calibrated rotameters and precision needle valves, supporting consistent air delivery up to 10 L/h.
• Integrated overtemperature safety cutoff: automatic power disconnection if measured temperature exceeds user-defined limits by more than 5 °C, preventing sample degradation or equipment damage.
• Rugged stainless-steel construction with insulated heating chamber and ergonomic front-access design for routine laboratory use and long-term reliability.

Sample Compatibility & Compliance

The FK35100 is validated for use with a broad spectrum of petroleum-based and synthetic lubricants—including aviation turbine oils (MIL-PRF-23699, MIL-PRF-83133), hydraulic fluids (MIL-H-5606, MIL-H-83282), engine oils, and transformer insulating oils. Its operational methodology conforms strictly to ASTM D4636 (Oxidation Stability of Turbine Oils by Rotating Pressure Vessel—RPVOT), ASTM D5968 (Corrosion Testing of Lubricating Oils Using Copper Strip), ASTM D6594 (Oxidation Stability of Lubricating Greases), and U.S. Department of Defense test methods FTM 791-5307 and FTM 791-5308. These standards are routinely referenced in OEM specifications, military procurement contracts, and ISO 9001-certified quality assurance programs. Instrument design supports GLP-compliant execution when paired with documented SOPs and calibrated reference materials.

Software & Data Management

The FK35100 operates as a standalone benchtop unit without embedded software or network connectivity. All process parameters—including temperature setpoints, airflow rates, and test duration—are manually configured and monitored via front-panel controls and analog/digital instrumentation. For laboratories requiring electronic data capture, integration with external data loggers or LIMS platforms is supported through standard 4–20 mA or 0–10 V analog outputs (optional accessory). Temperature profiles and airflow values can be recorded at user-defined intervals to support audit readiness under FDA 21 CFR Part 11 (when used in pharmaceutical-grade lubricant qualification) or ISO/IEC 17025 accreditation frameworks.

Applications

• Quality control of new lubricant batches prior to release into aerospace or defense supply chains.
• Comparative evaluation of antioxidant package efficacy during formulation development.
• Failure analysis of in-service oils exhibiting premature varnish or sludge formation.
• Validation of re-refined base oil performance against virgin stock specifications.
• Supporting regulatory submissions for lubricant approval under FAA Advisory Circular AC 20-135 or NATO AEP-102 requirements.

FAQ

What standards does the FK35100 directly support?
It is engineered and verified for ASTM D4636, D5968, D6594, and U.S. DoD FTM 791-5307/5308 test procedures.

Can the instrument accommodate non-standard sample geometries or custom coupons?
Yes—the sample wells accept standard 100-mL glass tubes and ASTM D130 copper strips; alternative coupon holders (e.g., steel, aluminum) may be installed with mechanical verification of thermal contact and airflow symmetry.

Is calibration traceable to NIST standards?
Temperature sensors are supplied with individual calibration certificates traceable to NIST; users are advised to perform periodic verification using certified dry-block calibrators per ASTM E74 or ISO/IEC 17025 guidelines.

What maintenance is required for long-term accuracy?
Routine cleaning of air pathways, verification of rotameter calibration every 12 months, and annual inspection of heater elements and thermocouple integrity are recommended per Koehler’s Maintenance Protocol K-MP-FK35100 Rev. 3.