His ability to become drunk on a single cup of liquor is genetic. If you are requesting multiple posters, please add that request to the additional comment section. He has light eyes and long eyelashes, and dresses in the characteristic white robes. Order your FREE Viscosity Cup Conversion Chart here!įill the form below or call 80 or 30 to request your Viscosity Cup Conversion Chart Poster today. This chart is not meant to take the place of making the actual measurement. This chart is a guide to convert the efflux time, in seconds, measured with a given viscosity cup to the efflux time an alternate cup would measure using the same fluid. efflux time, and suggested standard oils for each cup. The poster also includes instructions for using the chart, standards, specifications, viscosity equations, centistokes vs. The Viscosity Conversion Chart poster compares the efflux times of the BYK-Gardner Zahn cups, S90 Signature Zahn cups, EZ Zahn cups, Ford cups, Din Cup 4mm, and ISO cups. If you interested in ordering a free poster, BYK-Gardner Laboratories Blog has included the form to order your viscosity poster at the bottom of this post. Each cup is supplied with a conversion table to determine viscosity in centistokes (cSt) from the. After withdrawing the cup, measure the time it takes until the first break in the liquid stream. Simply fill the cup by immersing it in the test liquid. Gardner Co in their helpful Excel spreadsheet downloadable from Viscosity Cup Equivalent Wall Chart, where K and C are provided for the most popular cups.Īccording to the excellent book The Printing Ink Manual by Robert Leach, the single-operator accuracy of these cups is in the 5-10% range and the multi-operator accuracy in the 10-30% range, with ISO cups being best and Zahn cups being worse.BYK-Gardner has a free Viscosity Cup Conversion Chart Poster that is available for your offices, labs or facilities around the world. Easily measure viscosity using an EZ viscosity cup and a stopwatch. One supplier said words to the effect of "We're not changing our cups to meet ASTM standards because our users would be confused between old and new cups."įor this app I used the simple formula η = K.t-C/t used by the Paul N. page 33 efflux time in seconds temperature gardco ez cup 4 g-200 standard oil 36.00 seconds 458.6 centistokes 25 degrees degrees celsius gardco ez cup 5 g-350 standard oil 38.06 seconds 877. ![]() In preparing this app I looked at many such tables and a 20s Zahn #2 cup viscosity varies from ~20-45cP depending on the table. If you have ever measured a real viscosity and compared it to a value from one of the "standard conversion tables" you will probably be surprised at the difference. Because these cups actually measure the kinematic viscosity in cSt (a denser liquid flows out faster), enter your estimated density to allow the conversion (cP=cSt*ρ). ![]() Here you can choose from one of a few types of cup, specify your time in the 15-60s range and get an estimate of the viscosity in cP. I hope that is not the case! All I am doing is helping those, like me, who want to have some idea of what is going on when the only data available are measurements from these cups. Second, they assume Newtonian viscosity, so they tell you nothing about shear thinning.Īn expert in the field has warned me that this app might add legitimacy to the use of these cups. ![]() First they are not accurate even when done properly (see below) and even less when they aren't cleaned properly between use, etc. mPa.s or cP as a convenient unit) is being used. ![]() I find it very annoying that in the 21st century such unscientific devices are used and get frustrated that no one (including me) has any idea what approximate viscosity in real units (i.e. The size of the hole is in mm and a Zahn #4 means a Zahn cup with a 4mm hole. Different cups have different shapes and hole sizes and because times too short or too long are unsuitable, for any given viscosity there is an optimum cup with times in the 15-60s range. Many printers/coaters measure their viscosity using cups with holes in the bottom by finding how many seconds it takes to empty the full cup (or, rather, for the flow to "break").
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