Sieve shaker

A number of less expensive sieve shakers are on the market, such as the Dynamic, by Soiltest Inc., Chicago the Cenco-Meinzer, by Central Scientific Co., Chicago the Tyler portable, by W. S. Tyler, Inc., Mentor, Ohio and also a number of electromagnetic vibratory shakers. The latter should be used only when strict comparability with other tests is not required, since it is difficult to be sure that identical intensity of vibration was present in the tests being compared. 

Whitby (Ref 7) discovered that in the nonsteady-state with mechanical sieve shakers, the percentage passing versus sieving time curve could be divided into two regions with a transition between (Fig 4). Region 1 exists when there are many particles much less than the mesh size still on the sieve, while region 2 exists when the residue on the sieve consists entirely of nearmesh or larger particles... 

Vibratory sieve Shaker for micro precision sieving... 

Laboratory sieving devices vibratory sieve shaken for micro-precision sieving, Analysette 3, rotary sieve shaker, Analysette 18... 

Pour the sample into the top sieve, place on a sieve shaker, and shake for 5 min. Obtain the new weight of each test sieve to the nearest 0.1 g. 

Pellet size distribution ASTM D 1511 determination by means of sieve shaker... 

Method of analysis (Re-Tap sieve shaker, SediGraph particle size analyzer, or other equipment) ... 

In a laboratory the distribution is determined in a sieve shaker (figure 9.2). This consists of a number of stacked sieves and a container at the bottom. The sieves are mounted on a shaking device and the shaking time and frequency can be adjusted. 

Horizontal rotary motion produced by a Ro-Tap sieve shaker, without the aid of the hammer or bumper. 

Sieve Shaker Use a mechanically operated sieve shaker that imparts to the set of sieves a horizontal rotary motion of between 270 and 300 rotations/min and a tapping action of between 140 and 160 taps/min. The sieve shaker is fitted with a plug to receive the impact of the tapping device. The entire apparatus is rigidly mounted—bolted to a solid foundation, preferably of concrete. Preferably a time switch is provided to ensure the accuracy of test duration. 

The USP uses descriptive terms to characterize the particle size of a given powder, which are related to the proportion of powder that is capable of passing through the openings of standardized sieves of varying dimensions in a specified time period under the mechanical sieve shaker as follows ... 

Machine sieving is carried out by stacking the sieves in ascending order of aperture size and placing the powder on the top sieve. A closed pan, a receiver, is placed at the bottom of the stack to collect the fines and a lid is placed at the top to prevent loss of powder. A stack usually consists of five or six sieves in a root two progression of aperture size. The stack of sieves is clamped on to a test sieve shaker that is vibrated for a fixed time and the residual weight of powder on each sieve is determined. Results are usually expressed in the form of a cumulative percentage of the nominal sieve aperture. 

The three essentials required in a test sieve shaker are An effective sieving action in order that an end-point is reached this end-point to be reached in a short time and reproducible results. 

Labcon PI 14 computer system consists of an Epsom Pine computer mounted in a purpose made portable case containing the necessary power supplies and interface components to allow control of a sieve shaker and electronic balance. Firmware in Epsom is included to provide a variety of methods of data handling and presentation procedures. 

The cascadograph consists of a stack of sieves of the same nominal aperture size in a shaking device (a Tyler Ro-Tap sieve shaker). Each stack consists of twenty 8 in diameter sieves specially made by the Newark Wire Cloth Company Newark sieve cloth is claimed to have very uniformly sized apertures and a low tendency to blind. ... 

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