British standard sieves

BSS British Standard Sieve CR chloroprene robber, polychkxoptene... 

Screen sizes are defined in two ways by a mesh size number for small sizes and by the actual size of opening in the screen for the larger sizes. There are several different standards in use for mesh size, and it is important to quote the particular standard used when specifying particle size ranges by mesh size. In the UK the appropriate British Standards should be used BS 410 and BS 1796. A comparison of the various international standard sieve mesh sizes is given in Volume 2, Chapter 1. 

BS410 1962 British Standard 410 (British Standards Institution, London). Specification for test sieves. 

TABLE 12.1. Comparison Table of United States, Tyler, Canadian, British, French, and German Standard Sieve Series... 

A series of fine mesh, std test sieves of specification governed by British Standards Spec No 410-1943, available from BSI, Victoria St, London SW1. These sieves with their mesh numbers openings are compared with US,... 

United States Standard Sieve Series, ASTM E-ll-01 Canadian Standard Sieve Series, 8-GP-16 British Standards Institution, London, BS-410-62 Japanese Standard Specification, JI S-Z-8801 French Standard, AFNOR X-11-501 German Standard, DIN-4188... 

The I.M.M. Series has been superseded by the British Engineering. Standards Association Series (1932). This sieve series is also shown in Table 13. It will be noted that the openings follow closely those of the Tyler series, the differences being due to the desire of specifying British Standard Wire diameters. 

British Standard Specifications BS 410 [13] adopts a primary size of 75 pm (200-mesh) with a fourth root of two progression in size and suggest that alternate sieves should normally be used for an analysis (i.e. a root two progression of sizes). Thus, the specific surface area of particles on consecutive sieves is in a 2 1 progression. BS 1796 describes the methods to be used in sieving with woven wire and perforated plate sieves [14],... 

The apertures for the British Standard 400 mesh are 37.5 pm with a nominal wire thickness of 26 pm. On the basis of Table 4.1, in which a selection of sieve dimensions are shown, the (nominal) 75 pm sieve has a... 

The tolerances on sieve cloth are extremely wide, particularly for small aperture cloth. For example, the British Standard Specification (BS 410) for a 200-mesh sieve requires a median diameter of 75 plus or minus 33 pm. It is clear that oversize apertures are more undesirable than undersize, since the latter are merely ineffective whilst the former permit the passage of oversize particles. In order to reduce differences between analyses using different sets of sieves (differences of up to 42% have been recorded) manufacturers such as ATM make specially selected sieves [45] available that can reduce the differences by a factor of 10. 

Sample Preparation. The glass samples ( 100 mg) were carefully ground in an agate mortar and passed through a 200 British Standard mesh sieve. The finely ground samples (= 75 (xm) were placed in an electric oven at 105 °C for I h, cooled in a desiccator, and weighed prior to dissolution. (Sample weights of 30-100 mg have been analyzed successfully.)... 

There are several British Standards that deal with liquid pyknometry applied to specific materials12-13-141516. A pyknometer bottle of up to 50 ml volume is usually sufficient for fine powders but coarse materials may require larger calibrated vessels. BS 1377 1975, for example, requires the use of a 1 litre cylindrical gas jar, closed by a ground plate, to measure the density of soils that contain particles coarser than 2 mm BS test sieve (but not coarser than 37.5 mm). 

In firework formulas 81-124, unless stated otherwise, it is assumed that the chemicals are ground to pass a British Standard 120 mesh sieve (124 / ). Shellac 30/200 has a wide range of particle size and so gives a longer burning time. Red Gum or Acaroid Resin has a similar wide range but usually passes 80 mesh (190/i). 

The difference between U.S, Standard sieve numbers and British Standard is negligible for all practical purposes. Several books on particle size have comparative tables and detail figures on the two series and on others. 

Woven wire test sieves were formerly designated by a mesh number (the number of wires per inch) but as the important sieve characteristic is the size of its apertures all standard test sieves are now designed, by international agreement, by their aperture size in millimetres or micrometres. The aperture sizes in a standard series are related to one another, e.g. following a fourth root of two (1.189) or a tenth root of ten (1.259) progression. The two most widely used standard sieve scales are the American (ASTM Ell, 1995) and British (BS 410, 2000) both of which are compatible with the international scale (ISO 3310, 2000) (Table 2.11). 

There are several single-particle characteristics that are very important to product properties (Davies, 1984). They include particle size, particle shape, surface, density, hardness, adsorption properties, and so on. From all these mentioned features, particle size is the most essential and important one. The term "size" of a powder or particulate material is very relative. It is often used to classify, categorize, or characterize a powder, but even the term powder is not clearly defined and the common convention considers that for a particulate material to be considered powder, its approximate median size (50% of the material is smaller than the median size and 50% is larger) should be less than 1 mm. It is also common practice to talk about "fine" and "coarse" powders several attempts have been made at standardizing particle nomenclature in certain fields. For example. Table 1.1 shows the terms recommended by the British Pharmacopoeia referred to standard sieves apertures. Also, by convention, particle sizes may be expressed in different units depending on the size range involved. Coarse particles may be measured in centimeters or... 

Consulting the British Standards Screen Scale in Appendix 5, the nominal aperture sizes in micrometers are tabulated versus the weight retained. Then, the fractions retained on each of the sieves used in the test can be listed as percentage of the original test sample weight, and finally as the oversize cumulative percentages (i.e., running totals). The results of these calculations can be tabulated on a second table (Table 2.8). 

Summaries of sieve apertures according to the American standard (ASTM E 11-87) and the British standard (BS 410) are given in the Appendix. The American standard apertures are in the progression of 1. Originally the apCT-tures were determined taking 75 p-m as the reference value, but the current international standard (ISO) uses 45 p-m as the refo-ence value. 

Lawn. Term used in the British pottery industry for a fine-mesh screen or sieve. In the past, makers of these lawns gave them somewhat arbitrary numbers they are now largely replaced by meshes conforming to British Standards. 

British Standards committee GME/29/4 is concerned with "Particle sizing methods other than sieving". Its work covers not only particle size distribution analysis but also methods of estimation of surface area and pore size distribution, as well as a glossary of terms relevant to those subjects. 

British Standards committee GME/29/4 (formerly CPE/10/4) is charged with "Sizing by Methods other than Sieving". Test sieves and test sieving are covered by committees GME/29/1 and GME/29/2, under the chairmanship of Professor J.W. 

Table 13—The British Engineering Standards Association and I.M.M. Sieve...

Table 2.11. Comparison between the British and US standard wire mesh sieve scales showing the danger of using the mesh number as a sieve designation...

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