ERICHSEN #458 Viscosity & Temperature Conversion Chart Disk
| Origin | Germany |
|---|---|
| Manufacturer Type | Authorized Distributor |
| Origin Category | Imported |
| Model | #458 |
| Pricing | Upon Request |
Overview
The ERICHSEN #458 Viscosity & Temperature Conversion Chart Disk is a precision-engineered mechanical calculation tool designed for laboratory and production environments where rapid, traceable, and unit-consistent viscosity data conversion is required. Unlike digital instruments, this analog chart disk operates on fundamental rheological principles grounded in Newtonian fluid behavior and empirical temperature-viscosity relationships. It supports conversion between kinematic and dynamic viscosity units—including centistokes (cSt = mm²/s), centipoise (cP = mPa·s), Engler degrees, Krebs Stormer units, Gardner units, Hölt units—and flow time measurements standardized under ISO 2431 (4 mm orifice), ASTM D 1200 (Ford Cup No. 3 and No. 4), and DIN 53211. The device assumes reference temperature conditions between 15 °C and 25 °C, with temperature correction applicable across a validated range of 5 °C to 30 °C using a fixed thermal coefficient of 5.5 %/°C—consistent with classical Arrhenius-derived approximations for low-to-medium molecular weight liquids.
Key Features
- Double-sided rotating disk format enabling simultaneous access to viscosity unit conversion and temperature-correction scales
- Direct visual alignment mechanism eliminating transcription errors during manual conversion workflows
- Density-dependent cSt–cP correlation calibrated for liquids with specific gravity between 0.7 g/cm³ and 1.5 g/cm³
- No power supply, battery, or software dependency—ideal for cleanroom, explosion-proof, or audit-critical environments requiring deterministic traceability
- Compliant with legacy calibration practices referenced in ISO/IEC 17025-accredited viscosity testing laboratories
- Compact, durable acrylic construction with engraved scale markings resistant to solvent exposure and repeated handling
Sample Compatibility & Compliance
The #458 chart disk is intended exclusively for Newtonian or near-Newtonian fluids—such as mineral oils, solvents, thin resins, and aqueous solutions—where shear-rate independence can be reasonably assumed over the measurement range. Non-Newtonian samples (e.g., thixotropic paints, polymer melts, or suspensions) require alternative instrumentation such as rotational rheometers. While the chart itself is not a measuring instrument, its use aligns with documented procedures compliant with ASTM D1200, ISO 2431, and DIN 53211 for efflux cup-based viscosity determination. Its application supports GLP documentation requirements when integrated into controlled test methods referencing fixed-temperature reporting conventions.
Software & Data Management
A digital counterpart—VISCOSOFT 460-FC—is available as a standalone Windows-compatible application for automated conversion of efflux cup flow times into kinematic viscosity values, including batch export to CSV and PDF report generation. VISCOSOFT 460-FC implements identical temperature compensation algorithms and unit mappings as the #458 disk, ensuring method equivalence across analog and digital workflows. The software supports 21 CFR Part 11-compliant user authentication, electronic signature logging, and audit trail functionality for regulated QC/QA environments. However, the #458 chart disk remains fully functional independent of any software installation or network infrastructure.
Applications
- Quality control labs performing routine viscosity checks on incoming raw materials (e.g., base oils, thinners, monomers)
- Paint and coatings manufacturing facilities adhering to Ford Cup or ISO efflux cup specifications
- Technical service centers supporting field technicians requiring portable, non-electronic reference tools
- Educational laboratories demonstrating fundamental viscosity unit interrelationships and temperature dependence
- Regulatory submission support where paper-based, manually verified conversions are mandated by internal SOPs or historical method validation protocols
FAQ
Is the #458 chart disk suitable for non-Newtonian fluids?
No—it assumes linear stress–strain response and should only be applied to fluids exhibiting Newtonian behavior within the tested shear rate window.
Does the chart account for density variations beyond 0.7–1.5 g/cm³?
No; extrapolation outside this specific gravity range introduces systematic error in cSt–cP conversion and is not supported by the scale design.
Can the #458 disk replace formal calibration of viscometers?
No; it is a conversion aid—not a measurement device—and does not satisfy ISO/IEC 17025 requirements for instrument calibration or uncertainty quantification.
What is the basis for the 5.5%/°C temperature coefficient?
This empirically derived value reflects typical viscosity temperature sensitivity for hydrocarbon-based liquids near ambient conditions and aligns with literature values cited in ASTM D341 Annex A.
Is the chart disk compliant with FDA or EU regulatory frameworks?
While not certified per se, its use is compatible with GMP/GLP environments when embedded in validated, documented procedures referencing recognized standards (e.g., ASTM, ISO, DIN).
