Instead Of Listing The Precision Of Glass Capillary Viscometers by Todd Viscometer
we now offer expanded uncertainty. It is universally accepted statistics when it comes to calibration data. For A2LA accreditation, determine and specify the expanded uncertainty.
ISO publications define expanded uncertainty as "the interval of a measurement result in which the values that could reasonably be attributed to the measurand may be expected to lie with a high level of confidence."
The use of the expanded uncertainty rather than precision does not reflect any change in the accuracy or quality of Cannon . It is a statistical term that is broader than accuracy. When comparing the accuracy of the viscometer, it is essential that the expanded uncertainty is specified.
A certificate stating the expanded uncertainty is provided with each calibrated viscometer. We also provide such a certificate with each bottle of the standard viscosity.
Glass capillary - TYPES
Follow the blue links below for full information, photos and ordering information.
Cannon-Fenske Routine viscometer Cannon-Fenske Routine viscometer is a robust and inexpensive that works well, if the liquid can be measured is transparent or translucent. In general, if the meniscus (the curvature at the top of the liquid column) can be easily observed through a liquid column of 3 mm in diameter, Cannon-Fenske Routine viscometer and other transparent-type viscometers (such as transparent and Zeitfuchs BS / U-Tube ) can be used.
Ubbelohde viscometer Ubbelohde, suspended and no other level is also used to measure transparent liquids. Unlike the Cannon-Fenske Routine viscometer, suspended level have the same viscometer constant at all temperatures. This function is useful when measurements are taken at various temperatures. has improved the design of Ubbelohde viscometer to make the tool more robust Ubbelohde viscometer called Cannon-. Others depend on the level in this release are the BS / IP / SL, a BS / IP / SL (S), and BS / IP / MSL .
Reverse flow have been specially designed for testing opaque liquids. These reverse-flow type viscometers wet the timing section of the viscometer capillary only during the actual measurement. The Cannon-Fenske Opaque, arm Zeitfuchs Cruz and BS / IP / RFU-tube viscometers available from the Society of instruments of all kinds of reverse flow. Reverse flow viscometers must be cleaned, dried and refilled before repeating the measurement can be done. In contrast, other viscometer types commonly used to measure transparent liquids allow the sample to be repeatedly drawn into the capillary, which allows measurements in duplicate.
Small volumes Viscometers In some situations, as in a clinical laboratory, the amount of liquid available for measurement is quite low. Several viscometers have been designed which require one milliliter or less of liquid. These are called semi-micro viscometers or a microphone. The Cannon-Manning Semi-Micro viscometer is a U-tube, which was modified to measure the kinematic viscosity of samples as small as 1.0 ml. The Cannon-Ubbelohde Semi-Micro viscometer is a modification of the size Cannon-Ubbelohde viscometer standard requiring a sample volume of one milliliter. The Cannon-Manning Semi-Micro viscometer small additional charge will determine the kinematic viscosity with as little as 0.5 ml of sample.
Dilution viscometers estimates of molecular size and shape of a polymer can be a measure kinematic viscosity of dilute solutions of polymers. Ubbelohde viscometer dilution Cannon-has a large tank, which allows polymer solutions to be diluted several times. Dilute solutions of polymers often appear to show changes in kinematic viscosity when the shear rate is changed. By using the Cannon-Ubbelohde viscometer four bulb shear dilution, measurements can be performed in four different cutting speeds.
Vacuum viscometers most glass capillary viscometers, the sample stream by gravity. When liquids are too viscous to flow easily by gravity, vacuum viscometers may be used to measure the viscosity (in mPa â
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