ProductsFAQViscometry / The right choice

The right choice

FAQ | The right choice
Questions Answers
Which device is the suitable one for me (selection scheme)? We can not offer a general selection scheme at this time, as the demands and prerequisites of our customers are too varied. Please contact SI Analytics or our sales partners by telephone or by e-mail for a non-committal consultation:
Starting at which number of samples does an automation pay off? A ViscoClock is already profitable for a small number of samples based on its low acquirement cost, e.g. for the occasional measurement of oils. An AVS®370 or AVS®470 is profitable if you are regularly measuring about 5 samples per day. In addition to the advantages of less work, there is also the high reproducibility and safety that play an important role - the latter especially with typical polymer applications, where you work with aggressive samples that are hazardous to your health.
For which applications should an opto-electronic probing be used for automatic viscosity measurements and for which a thermo-electric probing? The opto-electronic probing is the standard method for transparent liquids. It is also suitable for colored oils or strongly dyed solutions, such as the deep blue CuEn, a solvent for cellulose. The thermo-electric TC viscosimeter is used for opaque liquids, especially for used oils. As the thermistor sensors are surrounded by glass and melted tightly into the viscosimeters, you can also measure conductive and very aggressive liquids. As the thermistor sensors become hot during use (up to 150°C), TC viscosimeters should not be used for samples where solvents may evaporate: Impairment by the formation of incrustations on the sensors.
When is the AVS®Pro profitable? An AVS®Pro system is usually used once a sample quantity of about 20 samples/day/shift is processed.
Which viscosimeter is suitable for my measuring process? SI Analytics generally recommends Ubbelohde or micro Ubbelohde viscosimeters: With this type of viscosimeter, the run time does not depend on the filled volume, so that the measuring accuracy is higher - with simpler ease of use, as you do not have to watch for accurate filling. Sometimes, the use of other viscosimeters is recommended: I. E. for measurements in the petrochemical area, traditionally, Cannon-Fenske viscometers are often used, and for foaming samples (e.g. beer, blood), micro Ostwald viscometers have proven to be effective. All viscosimeters are available in different capillary sizes, which must match the respective sample viscosity, so that the run time is between 100 and 500 seconds.
Are there also micro viscosimeters and how big does the minimum sample volume need to be? Micro Ubbelohde viscosimeters and micro Ostwald viscosimeters require only 3 to 4 ml or 2 ml of sample volume.