Sieve analysis screening

Sieve analysis (screen analysis) n. The separation of particulate solids into sequentially finer size fractions by placing a weighed sample into the topmost of a stack of graded standard sieves, mechanically shaking and tapping the stack for 10 min, then weighing the material collected on each... 

Siebanalyse sieve analysis, screen analysis Siebbodenkaskadenreaktor/ Lochbodenkaskadenreaktor sieve plate reactor Siebdurchgang/ Siebunterlauf/Unterkorn sievings, screenings, siftings undersize... 

Molekillsieb, Molsieb sieve vb (sift/screen) sieben sieve analysis/ screen analysis Siebanalyse sieve material/ sieving material/ material to be sieved Siebgut... 

DRY SIEVING OR SCREEN ANALYSIS WOVEN WIRE SIEVES... 

Sieve analysis, based on either vibratory or suction principle, uses a series of standard sieves calibrated by the National Bureau of Standards. The method is generally used for screening coarse particles down to a material as fine as 44 pm (No. 325 sieve). Sieves produced by photoetching and electroforming techniques are now available with apertures from 90 down to 5 pm. 

Sieves are used in screen, or sieve, analysis. This is an inexpensive and reliable method for classifying larger particles based on size and mass. Screen analyses are generally used for quality control and analytical work and find use in a wide variety of industries. They are not suitable for emulsions, sprays, or very fine powders (<0.05 mm in diameter). 

A screen used for a sieve analysis has a designation of 60 mesh. What does this indicate ... 

Finally, one aspect that can pay a role in compositional studies is the sieve (screening) analysis. Like all petroleum products, sampling is, or can be, a major issue. If not performed correctly and poor sampling is the result, erroneous and very misleading data can be produced by the analytical method of choice. For this reason, reference is made to standard procedures such as the Standard Practice for Collection and Preparation of Coke Samples for Laboratory Analysis (ASTM D346) and the Standards Test Method for the Sieve Analysis of Coke (ASTM D293). 

Sieve analysis using standard mesh screens is commonly used to determine particle size and size distribution of pellets and the reader is referred to standard texts for further information (61). Several types of densities have been defined for pellets based on interparticulate (void fraction) and intraparticulate pore volumes and include true, apparent, effective, bulk and tapped. The bulk and tapped densities may be obtained using simple devices, such as that used to evaluate granulations in tableting, while the true and apparent densities need more complex techniques based on mercury intrusion, gas flow, powder displacement, imaging or minimum fluidization velocity (62). 

The dune sand by itself does not meet the requirements of ASTM C-33 for fine aggregates. However, such deficiency is sometimes corrected by compensating with screened aggregate obtained from crushing of limestone. A typical dune sand sieve analysis is shown below (12). 

Receipts of active ingredient raw materials B1 and B2 are accepted by quality control based on standard tests for potency, chemical attributes, and particle size. Particle size is determined by sieve analysis. Unfortunately, this is a limit test in which 99% of the sample must pass through a certain mesh screen, therefore any influence particle size distribution might have on dosage form potency cannot be examined. 

SatnpCe Preparation. Seventy grams of sample, previously calcined at 538°C, was dispersed in about 125 mL of sodium metaphosphate solution and "wet screened" using a sieve stack of 250, 270 and 325 mesh, 8-inch diameter sieves. The sieves were washed with water until the effluent was free of any particulate and then rinsed with acetone to de-water. After air drying, the contents of each sieve were transferred to a porcelain dish and the material was recalcined at 538°C. Appropriate weights taken during this procedure allowed for the determination of percent moisture in the starting material and sieve analysis relative to the appropriate sieve fractions. The total +325 mesh material was recombined and mixed for the test. 

Many industries have large data banks on product size distributions by sieve analysis and want to continue using this form of presentation. In order to accommodate this need Cho et. al. [48] converted Sedigraph data to sieve data using wet screened powder in the 38 to 53 pm size range and fitted the data to a logarithmic distribution to give the slope and median size. This procedure must be use with caution since the conversion factors are shape dependent and a new calibration is required for each product. 

In sieve analysis, standard screens with precise screen openings are arranged in a stack from the coarsest to the finest with a pan below the bottom sieve to collect the fines. The material is introduced on the top screen and the stack of sieves is vibrated such that the material will stratify by particle size through the sieves. 

After a given time period, the stack is disassembled, and the weight of the material retained on each screen is measured and expressed as a percentage of the total. A typical sieve analysis is found in Table 12.2. 

Table 2 Sieve Analysis Summary Percent Retained on Screens...

The grading of a gravel pack in a well should be based on a sieve analysis of the finest aquifer materials of the screened zone. The screen slot opening should retain 90 percent or more of the gravel pack material. The gravel pack material should be clean, with well-rounded grains that are smooth and uniform. These characteristics increase the permeability and porosity of the pack material. 

The result of a sieve analysis is a tabulation of the mass of powder (or mass fraction) of each screen increment. Two numbers are required to specify the particle size the screen through which the particles pass and the screen on which they are retained. The data may be reported as 120/170—the particles were retained on the 170 mesh screen and passed through the 120 mess screen. 

Electronic balances, magnetic stirrers, and sieves for screen analysis. 

Size analysis is useful in assessing problems in coal transportation and handling. For larger sizes coals, hand or mechanical sieving or screening is undertaken fines (< 1 mm) are better screened in humid medium while for ultrafines (<0.06 mm) optical or electrical field effect techniques are more appropriate. 

Partide-Size Anal is- Particle-size distribution is normaUy measured by conducting a screen analysis" (sieve analysis) of a representative sample on 20-cm-diameter sieves. The sample size recommended for testir on these sieves varies according to the size range of the material. The sieves selected for use are stacked, with sieve apertures increasing in size from bottom to top in the stack. The sample is placed on the uppermost sieve of the stack, and the stack is placed on... 

There may be inaccuracies in the value of 30 as taken from a screen analysis in this size range the sieve analysis is only approximate because of aggregation of the particles. 

Sieve fraction n. The mass fraction of a sieve-analyzed powder found between two successive screens in a sieve analysis. For example, one might say, The —0.420, +0.250-mm fraction was 15.27% . 

Sieving n. Separation ofa mixture of varioussized particles, either dry or suspended in a liquid, into two or more portions, by passing through screens of specified mesh sizes. See sieve analysis. Also known as screening. 

Dry-sieve analysis is the easiest and the most convenient method for measuring granule size. The granulation is placed on top of a stack of five to six sieves which have successively smaller-sized openings from top to bottom. The stack is vibrated, and the particles eollect on top of the sieves. The data are usually represented in terms of percentage retained on the sieve, or percentage that is undersize or oversize vs. screen-opening size (Fig. 4) (6). 

Figure 4 Sieve analysis of lactose granules formed by massing and force screening showing effect of binder fluid level circles, 15.3% v/v squares, 18.4% v/v upward triangles, 23% v/v and downward triangles, 30.6% v/v. (From Ref. 6.)...

The result of the particle size analysis (screen or sieve analysis) can be represented in a numerical table and/or as a particle size cumulative distribution curve... 

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