Koehler K13009 Saybolt Colorimeter
| Brand | Koehler |
|---|---|
| Origin | USA |
| Manufacturer Status | Authorized Distributor |
| Origin Category | Imported |
| Model | K13009 |
| Price Range | USD 6,800 – 13,600 |
Overview
The Koehler K13009 Saybolt Colorimeter is a precision optical instrument engineered for the standardized visual determination of Saybolt color—a critical physical parameter in petroleum product quality assurance. Based on the principle of comparative visual color matching under controlled illumination, the instrument implements the classical Saybolt method defined in ASTM D156 and GB/T 3555. It operates by vertically adjusting the height of a transparent sample column in a calibrated glass tube until its apparent color—viewed through a fixed optical path against a standardized reference scale—is just perceptibly lighter than the assigned standard color plate. The corresponding liquid column height (in inches) is then converted to the dimensionless Saybolt color number via ASTM-referenced conversion tables. Saybolt color values range from −16 (darkest, highly colored naphthenic oils) to +30 (lightest, water-white distillates), with higher values indicating greater refinement and lower aromatic or oxidation-related chromophore content. This method remains indispensable for routine QC in refineries, independent testing labs, and regulatory compliance workflows where trace-level color deviation signals thermal degradation, contamination, or inadequate hydrotreating.
Key Features
- Full compliance with ASTM D156, IP 15, ISO 2049, and GB/T 3555 test protocols—validated for audit-ready documentation.
- Integrated tungsten-filament lamp assembly with diffused, shadow-free illumination optimized for consistent chromatic perception across operators and shifts.
- Stainless-steel base and rigid aluminum housing ensure mechanical stability during column height adjustment and long-term repeatability.
- Includes full set of certified Saybolt standard color tubes (±0.5 unit tolerance), neutral gray reflector plate, full-color and half-color correction filters, and precision-machined sample tube with integrated drain valve.
- Compact footprint (14 × 14 × 67 cm) and lightweight design (4.1 kg net) support benchtop deployment in QC labs, mobile field units, or third-party certification facilities.
- Optical path geometry conforms to ASTM-defined viewing angle (20° from vertical), eye-to-sample distance (305 mm), and background reflectance specifications to minimize observer bias.
Sample Compatibility & Compliance
The K13009 is validated for clear, non-opalescent, non-fluorescent petroleum liquids including unleaded gasoline, aviation gasoline (AVGAS), jet fuel (Jet A/A-1), naphtha, kerosene, white mineral oil, and paraffinic solvents. It is not suitable for waxy, viscous, or turbid samples—those require the dedicated Koehler K13190 Saybolt Wax Colorimeter per ASTM D6045. All measurements must be performed at 25 ± 1°C, with samples filtered to ≤0.8 µm prior to loading. Instrument calibration is traceable to NIST-certified reference standards; routine verification uses primary standard color tubes supplied with each unit. Data generated meets GLP/GMP documentation requirements when paired with laboratory-controlled observation logs and operator qualification records.
Software & Data Management
As a manual visual comparator, the K13009 does not incorporate digital readout or embedded software. However, it fully supports electronic data capture within regulated environments: column height readings and final Saybolt values may be entered into LIMS or ELN platforms compliant with 21 CFR Part 11 (e.g., LabWare, Thermo Fisher SampleManager). Koehler provides a validated Excel-based conversion tool (NIST-traceable coefficients) for automated height-to-color translation, with audit trail functionality for version control and change history. Calibration certificates, standard tube lot reports, and instrument verification logs are supplied in PDF format for archival in quality management systems.
Applications
- Routine specification testing of finished gasoline and jet fuels against refinery internal limits and API RP 1004 thresholds.
- Batch release verification for white oils used in pharmaceutical excipients (USP ) and food-grade lubricants (NSF H1).
- Investigation of color reversion in hydrotreated naphthas following storage or exposure to ambient light.
- Root cause analysis of off-spec color in kerosene destined for aviation turbine fuel blending streams.
- Supporting ASTM D3241 (Jet Fuel Thermal Oxidation Stability) by establishing baseline color prior to thermal stress testing.
FAQ
What is the measurement range of the K13009 Saybolt Colorimeter?
Saybolt color values from −16 to +30, corresponding to sample column heights from 0.25 to 4.00 inches (6.35 to 101.6 mm) per ASTM D156 Annex A1.
Can the K13009 be used for diesel or lubricating oils?
No—diesel fuel and most lube oils exceed the upper limit of the Saybolt scale and exhibit opacity or fluorescence; ASTM D1500 (ASTM Color) or ASTM D6045 (Wax Color) methods apply instead.
Is operator training required for ASTM-compliant results?
Yes—ASTM D156 mandates documented observer qualification, including Ishihara color vision testing and supervised proficiency assessment using certified reference materials.
How often must the standard color tubes be replaced?
Per Koehler’s service bulletin, standard tubes should be recalibrated annually or after 500 test cycles; physical inspection for scratches, cloudiness, or discoloration must occur before each use.
Does the instrument include a certificate of conformance?
Yes—each K13009 ships with a factory-issued Certificate of Conformance (CoC) referencing ASTM D156, serial-numbered standard tube calibration data, and electrical safety certification (UL/CSA 61010-1).
