Range of product size

A series of classification pockets, with decreasing quantities of hydraulic water in each, producing a range of product sizes. 

Crushing is applied to large lumps of feed stock and grinding to smaller lumps, often the products of crushing, but the size distinction is not overly sharp. The process of size reduction results in a range of product sizes whose proper description is with the complete cumulative size distribution, but for convenience a characteristic diameter corresponding to 80% pass in the cumulative distribution curve is commonly quoted. 

Overall economy in terms of human effort, materials, power, etc., in the production and exchange of goods. Standards promote economy through variety reduction. The nature of the standard will determine where the reduction lies, for example in a range of product sizes, a number of different types of equipment, or a variety of test methods. 

There is a wide range of product sizes and variable thicknesses. 

Of the three worldwide manufacturers of poly(ethylene oxide) resins. Union Carbide Corp. offers the broadest range of products. The primary quaUty control measure for these resins is the concentrated aqueous solution viscosity, which is related to molecular weight. Specifications for Polyox are summarized in Table 4. Additional product specifications frequendy include moisture content, particle size distribution, and residual catalyst by-product level. 

Another method iavolves an electric-arc vaporizer which is >2000° C before burning (25,32). One of the features of the process is a rapid quench of the hot gas flow to yield very fine oxide particles (<0.15 nm). This product is quite reactive and imparts accelerated cure rates to mbber. Internally fired rotary kilns are used extensively ia Canada and Europe and, to a limited extent, ia the United States (24). The burning occurs ia the kiln and the heat is sufficient to melt and vaporize the ziac. Because of the lower temperatures, the particles are coarser than those produced ia the other processes. In a fourth process, ziac metal which is purified ia a vertical refining column is burned. In essence, the purification is a distillation and impure ziac can be used to make extremely pure oxide. Also, a wide range of particle sizes is possible (33). 

Wood FIa.ke Boards. This category covers a range of products depending on the size and orientation of the wood flakes used. The earliest product was made in the 1950s using low density wood species, such as aspen and pine, with the flakes bonded together with phenoHc resins. Today there are two types of flake board, waferboard and oriented strand board (OSB). 

Hot water boilers are potentially more susceptible to gas-side corrosion than steam boilers due to the lower temperatures and pressures encountered on low- and medium-temperature hot water boilers. With low-temperature hot water especially, the water-return temperature may drop below the water dewpoint of 50°C, causing vapor in the products of combustion to condense. This, in turn, leads to corrosion if it persists for long periods. The remedy is to ensure that adequate mixing of the return water maintains the water in the shell above 65°C at all times. Also, if medium or heavy fuel oil is to be used for low- or medium-temperature applications it is desirable to keep the heat transfer surfaces above 130°C, this being the approximate acid dewpoint temperature of the combustion gases. It may be seen, therefore, how important it is to match the unit or range of unit sizes to the expected load. 

Marked changes occur in the visible appearance of dehydrated foods with variation in particle size. It has been found that this effect is chiefly one of variation in luminous reflectance, Y (see Tables I and II). In some instances (note the data for cabbage), chromaticity (x, y) remains so nearly constant over a fairly wide range of particle size that it appears possible that for certain products and purposes the effect of particle size might be eliminated by the choice of chromaticity as a color variable. 

As formerly mentioned, the whole Dryex system can be sized over a wide range of production capacities since it is constituted by two main sections, each one characterized by high flexibility, the specific size of the drying/concentra-tion section can be decided with respect to the production rate of the first section as well as to the specific production route and need of the surfactant makers. By taking these factors into account, the drying/concentration equipment can be easily and conveniently coupled with already existing and running sul-fonation/sulfation plants to increase their industrial potential. 

The design of explosives is a matter of major importance to the manufacturer. The explosives industries of the world are extremely competitive and it is essential that products should be as cheap as is possible. A range of products must be provided such that one of them at least will be suitable for every type of work for which explosives may be required. A typical range, apart from special sizes, would be about thirty. 

Products that are suited to long-distance transportation usually have a wide range of particle size (e.g., fly ash, d = 1 to 300 pm), and it is difficult to represent adequately such materials by the single diameter required by most models... 

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