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Cannon-Fenske Opaque
+ infoDynamic viscosity measurement for laboratory and industrial applications
Dynamic viscosity measurement is essential for evaluating how liquids and semi-solid materials resist flow under applied force. Accurate viscosity data supports product development, quality control and process optimisation across a wide range of industries.
Fungilab provides complete dynamic viscosity measurement solutions based on precision rotational viscometers, temperature control systems and specialized accessories designed to deliver reliable, repeatable and traceable laboratory results.
Whether measuring low-viscosity liquids or highly viscous materials, Fungilab offers instruments adapted to routine laboratory testing as well as demanding research applications.
Our products
Viscolead Series
Viscolead ONE
Viscolead ADV
Accessories
LABORATORY DIVISION
Dynamic viscosity
Viscosity is part of the science of Rheology which quantifies the resistance materials give to changing shape.
Proper interpretation of viscosity data can reduce the rate of rejects while keeping production and formulation development costs to a minimum. Consistent product quality is ensured through proper viscosity measurements, either alone or in conjunction with compatible tests.
Dynamic viscosity testing can help with:
- Material characterization or “finger-printing”
- Standard testing methods to check for differences between batches
- Indirect way of measuring quality
- Product formulation
- Quality control
- Process control
- Design, optimization and operation of process equipment
Material characterization or “finger-printing”
Standard testing methods to check for differences between batches
Indirect way of measuring quality
Product formulation
Quality control
Process control
Design, optimization and operation of process equipment
Viscosity types
Dynamic viscosity
Centipoise (mPa*s)
Kinematic viscosity
Centistokes (mm2/sec)
Apparent viscosity
Centipoise (mPa*s)
Newton’s Law
According to Newton’s law, the viscosity of a fluid is constant. As shear rate changes, shear stress changes in proportion such that viscosity is constant. Common fluids that exhibit such behavior are:
Unfortunately for us, not all fluids follow Newton’s law. In fact, most fluids do not. For this reason, fluids are classified into two categories:
Rotational Viscometer
The viscosity is calculated from the measured torque and rotational speed, as well as the dimensions of the measuring geometry.
A fluid’s resistance to flow is measured by the torque it exerts on the rotating shaft of the viscometer.
Absolute viscosity: the measuring geometry fulfills certain requirements (which is the case of coaxial spindles).
Relative viscosity: the dimensions of the measuring geometry are not well defined.
Advantage
Flexibility in:
- Viscosity Range
- Temperature range
- Shear rate range
Application
For Newtonian and non-Newtonian substances and temperatures different from room temperature.
Reverse-flow capillary viscometers for opaque Newtonian liquids
The Cannon-Fenske Opaque viscometer is specifically developed for measuring the kinematic viscosity of dark or opaque Newtonian liquids. Unlike routine capillary viscometers intended for transparent samples, its reverse-flow design allows accurate measurements when the liquid level cannot be clearly observed.
This makes the Cannon-Fenske Opaque particularly suitable for petroleum products, lubricants, oils and other highly coloured liquids requiring precise laboratory viscosity measurements.
International testing standards
Fungilab Cannon-Fenske Opaque viscometers are manufactured in accordance with internationally recognised standards, including:
- ASTM D445
- ASTM D446
- ASTM D2515
- ISO 3104
- ISO 3105
- UNE 400313
Main features
- Reverse-flow design for opaque Newtonian liquids.
- Suitable for highly coloured samples.
- High measurement accuracy and repeatability.
- Individual calibration certificate supplied.
- Designed for laboratory quality control and research.
Calibration and traceability
Every Cannon-Fenske Opaque viscometer is supplied with an individual calibration certificate issued under the accreditation requirements of a National Metrological Register, providing measurement traceability and confidence in laboratory results.
To obtain accurate kinematic viscosity measurements, temperature stability is essential. Fungilab recommends using the THERMOCAP precision bath to maintain controlled measuring conditions throughout the test.
Other capillary viscometer solutions
For transparent Newtonian liquids, Fungilab also offers the Cannon-Fenske Routine range. Additional capillary measurement solutions include the BS/U-Tube for transparent liquids, BS/IP/RF U-Tube for opaque liquids and Ubbelohde viscometers.
Typical applications
Cannon-Fenske Opaque viscometers are widely used for testing petroleum products, lubricants, oils and other opaque Newtonian liquids in quality control laboratories, research centres and industrial testing facilities.
Fungilab can recommend the appropriate viscometer constant according to the expected viscosity range, testing temperature and applicable international standard.
Frequently asked questions about the Viscolead ADV
What is a Cannon-Fenske Opaque viscometer?
It is a reverse-flow glass capillary viscometer designed for measuring the kinematic viscosity of dark or opaque Newtonian liquids that cannot be tested reliably using conventional routine viscometers.
Why use a Cannon-Fenske Opaque viscometer instead of a routine model?
The reverse-flow design makes it possible to measure opaque or highly coloured liquids where the liquid level cannot be clearly observed during a conventional capillary test.
Which standards does the Cannon-Fenske Opaque comply with?
It complies with ASTM D445, ASTM D446, ASTM D2515, ISO 3104, ISO 3105 and UNE 400313.
Does each viscometer include a calibration certificate?
Yes. Every Cannon-Fenske Opaque viscometer is individually calibrated and supplied with its own calibration certificate to ensure measurement traceability.
Which samples are suitable for Cannon-Fenske Opaque viscometers?
They are intended for dark or opaque Newtonian liquids such as petroleum products, lubricants, oils and other highly coloured fluids.
Why is temperature control important during capillary viscosity testing?
Kinematic viscosity is temperature-dependent, so stable thermal conditions are required to obtain accurate and repeatable measurement results.
What is the difference between Cannon-Fenske Opaque and Cannon-Fenske Routine?
Cannon-Fenske Opaque is designed for opaque or dark Newtonian liquids using a reverse-flow design, while Cannon-Fenske Routine is intended for transparent Newtonian liquids.
Which other capillary viscometers does Fungilab offer?
Fungilab also manufactures Cannon-Fenske Routine, BS/U-Tube, BS/IP/RF U-Tube and Ubbelohde capillary viscometers to cover a broad range of kinematic viscosity measurement applications.
