Cannon-Fenske Viscometers
For transparent liquids, Model 33-C
Cannon-Fenske Viscometers for Opaque Liquids – Model 34-C
Cannon-Fenske capillary viscometers, Model 34-C, are designed for the determination of the kinematic viscosity of opaque liquids by measuring the flow time of the sample through a calibrated capillary at a controlled temperature.
They comply with ASTM D445 and IP 71 test methods and are manufactured in accordance with ASTM D446 specifications.
They are particularly suitable for quality control and research laboratories, as well as for petrochemical applications, lubricants, oils, dark-colored products, and samples whose lack of transparency prevents the use of conventional viscometers intended for transparent liquids.
Measurements are normally carried out using a thermostatic bath. The measured flow time is multiplied by the viscometer constant to obtain the kinematic viscosity value, expressed in mm²/s or centistokes (cSt).
Main features
- Type: Cannon-Fenske capillary viscometer for opaque liquids
- Model: 34-C
- Application: opaque liquids and non-transparent samples
- Measured parameter: kinematic viscosity
- Measuring principle: gravity capillary flow
- Unit of measurement: mm²/s (cSt)
- For use with a temperature-controlled thermostatic bath
- Compliance: ASTM D445, ASTM D446, IP 71
- Available in different Sizes and viscosity ranges
The Size identifies the capillary configuration and determines the corresponding measurable viscosity range. Lower Sizes are suitable for less viscous liquids, while higher Sizes are intended for samples with higher viscosity.
Scientific blown glassware is manufactured through hot working of borosilicate glass, a material particularly suited to laboratory applications due to its high thermal and chemical resistance and excellent resistance to thermal shock. Shaping is carried out by localized flame heating, controlled rotation of the glass, and air blowing to obtain precise geometries, uniform wall thickness, and smooth transitions with minimal internal stress.
The main processing techniques include blowing, drawing, constriction, expansion, glass-to-glass sealing, and the manufacture of standard ground joints, connectors, hose connections, stopcocks, and special fittings. Particular attention is paid to concentricity, wall thickness uniformity, and the continuity of welded joints, all of which are essential for reliable performance during heating, vacuum operation, and fluid transfer.
After forming, the glassware undergoes controlled annealing to reduce internal stresses generated during hot working. This process improves mechanical stability and resistance to thermal shock, making the glassware suitable for both standard laboratory applications and custom-designed experimental systems.