Zahn viscosity cup

Rheopexy Saybolt viscosity Viscometer Viscous flow Yield value Weissenbert Rheogoniometer Zahn viscosity cup... 

Zahn viscosity cup n. A one-shot device for obtaining quick measurements in a roughly linear way of the kinematic viscosity of the test liquid, typically a free-flowing fluid. The cup fill of test liquid is brought to the desired temperature in a bath of heating medium, then held over a collection... 

Zahn viscosity cup The Zahn viscosity cnp is a small, U-shaped cup suspended from a looped wire, with an orifice of any one of five sizes at the base of the cup. The entire cup is submerged in the test sample and then withdrawn. The time in seconds from the moment the top of the cup emerges from the sample until the stream from the orifice first breaks is the measurement of viscosity. 

Conshohocken, PA, 1995 Patton, T. C, Paint Flow and Pigment Dispersion A Rheological Approach to Coating and Ink Technology, John Wiley and Sons, New York, 1979 Van Wazer, Lyons, Kim, and Colwell, Viscosity and Flow Measurement, Lyons Kim, Colwell, Interscience Pubhshers, Inc., New York, 1963) Air-Bubble Viscometer, Brookfield Viscometer, Ford Viscosity Cups, Stormer Viscometer, Viscosity and Zahn Viscosity Cup. 

A Zahn-type viscosity cup such as the one shown in Figure 12-6 is most commonly used. The test is carried out by simply dipping the cup in plastisol or other liquid to be measured and measuring the time interval in seconds from the moment of withdrawal until the stream of material flowing from the cup orifice breaks. Zahn cups of varying orifice diameters are available for measuring all types of liquids with varying viscosities. Many other types of viscosity cups, such as Shall and Ford viscosity cups, have also been developed (4). 

The typical properties or specifications of aqueous flexo and gravure ink are Viscosity, Zahn efflux cup (ref. ASTM D4212-99) 25 °C ... 

Orifice. Orifice viscometers, also called efflux or cup viscometers, are commonly used to measure and control flow properties in the manufacture, processing, and appHcation of inks, paints, adhesives, and lubricating oils. Their design answered the need for simple, easy-to-operate viscometers in areas where precision and accuracy are not particularly important. In these situations knowledge of a tme viscosity is uimecessary, and the efflux time of a fixed volume of Hquid is a sufficient indication of the fluidity of the material. Examples of orifice viscometers include the Ford, Zahn, and Shell cups used for paints and inks and the Saybolt Universal and Furol instmments used for oils (Table 5). 

Concentrated compositions that increase in viscosity when diluted are described in U.S. Patent 6,150,320. A Bostwick consistometer is used for all viscosity measurements and equivalence is offered to Brookfield measurements using Spindle no. 1, at 60 r/min, and the Zahn viscometer, no. 1 cup. A low-viscosity hard surface cleaning emulsion, approximately 12 mPa s, is described in U.S. Patent 5,934,375 that increases in viscosity upon dilution with water to 800 to 1200 mPas. 

Zahn cup n. A device for measuring viscosity of paints, varnishes, and flexographic or gravure inks. 

Numerous methods for measuring fluid viscosity exist, for example, capillary tube flow methods (Ostwald viscometer), Zahn cup method, falling sphere methods, vibrational methods, and rotational methods. Rotational viscometers measure the torque required to turn an object immersed or in contact with a fluid this torque is related to the fluid s viscosity. A well-known example of this type of system is the Couette viscometer. However, it should be noted that as some CMP slurries may be non-Newtonian fluids, the viscosity may be a function of the rotation rate (shear rate). An example of this is the dilatant behavior (increasing viscosity unda increasing shear) of precipitated slurries that have symmetrical particles [33]. Furthermore, the CMP polisher can be thought of as a large rotational plate viscometer where shear rates can exceed 10 s and possibly affect changes to the apparoit viscosity. The reader can refer to the comprehensive review of viscosity measurement techniques in the book by Viswanath et aL [34]. 

Zahn Cup. An orifice-type viscometer it has been used for the determination of the viscosity of glaze suspensions. (E. A. Zahn, Chem. Industries, 51, (2), 220,1942.)... 

Viscosity property of a material to increasingly resist deformation with increasing rate of deformation. This property is quantitatively defined as dynamic viscosity or coefficient of viscosity and is often used synonymously with apparent viscosity. The viscosity of adhesives is primarily determined by means of rotational or throughflow viscometers (DIN cup. Ford cup, Zahn cup). Adhesives generally show non-Newtonian behavior. In addition to temperature, any expression of viscosity must also refer to the measuring instrument and measurement parameters (rotating spindle, rate of shear, nozzle diameter). 

Viscosity measurements are made by Brookfield viscosimeter or Zahn cup. Readings of solids content, as a means of monitoring viscosity and water loss, can be made by refrac-tometer. Manufacturers of glues and compounds can supply customers with viscos-ity/solids and viscosity/temperature graphs. 

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