Product size

Prices for the different material groups (F —F ) are largely influenced by product size and shape and the quantity of production. Apart from product shape, the main price-determining factor is the performance factor K Prices for the powder, a sintered anisotropic ring, and a sintered anisotropic segment are roughly on the order of 1, 2, and 5, respectively. [Pg.198]

Cathodes are made from graphite, soft or hard lead, or copper. A production-size cell (81) may contain 44 anode units, each comprising five graphite plate electrodes 25-mm thick, 175-mm wide, and 1100-mm long. [Pg.514]

Each basic operation can be divided into one or more unit operations. Size reduction involves cnishing and grinding depending on the size of material handled, and these may be carried out in stages. Separations can be either soHds from soHds, based on size or mineral composition, or soHds from Hquids, ie, dewatering (qv). Size separation or classification is an integral part of any flow sheet, not only to meet product size specifications, but also to ensure a narrow size distribution for subsequent minerals separation circuits and to decrease the load and improve the efficiency of size reduction units which are energy intensive. [Pg.394]

Cla.ssifica.tion. Slurry leaving precipitation is classified into a coarse and one or more fine fractions, usually by elutriation in hydroclassifiers. Cyclones and combinations of hydroclassifiers and cyclones are gaining popularity. In smelting grade alurnina plants, the coarse fraction, called primary product, is sent to calcination the fine fractions, called secondary and tertiary seed, are recycled to be grown to product size. [Pg.134]

AU processed material is screened to return the coarse fraction for a second pass through the system. Process feed rates are matched to operating variables such as rpm speed and internal clearances, thus minimizing the level of excess fines (—200 mesh (<0.075 mm mm)). At one installation (3) the foUowing product size gradation of total smaller than mesh size (cumulative minus) was obtained ... [Pg.569]

In the spray-up process a reinforcement, usuaHy glass fiber, is substituted for the mat and a special spray gun simultaneously chops the glass fiber and appHes it with catalyzed resin to the mold surface. Hand rolling techniques then consoHdate the fiber and resin to conform to the mold surface contours. The shorter chopped fibers aHow for more intricate design detaHs than do mats. Both processes rely heavily on the operators skiHs for product quahty. These two processes require the least capital investment and have the largest product size capabHity of aH the processes. A single-surface mold produces a part with one controHed (usuaHy the visible) surface. [Pg.94]

Generally, as the product size becomes finer, the capacity of the separating device decreases. Thus, there are devices that can be fed hundreds of metric tons per hour (MTPH) and produce a 95% passing 50-p.m product but a device that produces 95% passing 5 p.m may have a capacity of ca 1 MTPH or less. [Pg.433]

In the suspension methods, agglomerate formation occurs by hardening of feed droplets into soHd particles, by layering of soHds deposited from the feed onto existing nuclei, and by adhesion of small particles into aggregates as binding soHds from the dispersed feed are deposited. The product size achievable in these methods is usually limited to ca 5 mm and is often much smaller (see Drying). [Pg.120]

Many attempts have been made to develop models which predict the behavior of materials undergoing size reduction. One proposal is that the energy expended in size reduction is proportional to the new surface formed (5). Another theory is that the energy required to produce a given reduction ratio (feed size product size) is constant, regardless of initial feed particle size (6). Practical results show, however, that both these theories are limited in their usehilness. [Pg.139]

Table 1. Breakage Distribution Function by Product Size Interval Number...

The summation term is the mass broken into size interval / from all size intervals between j and /, and S is the mass broken from size internal i. Thus for a given feed material the product size distribution after a given time in a mill may be deterrnined. In practice however, both S and b are dependent on particle size, material, and the machine utilized. It is also expected that specific rate of breakage should decrease with decreasing particle size, and this is found to be tme. Such an approach has been shown to give reasonably accurate predictions when all conditions are known however, in practical appHcations severe limitations are met owing to inadequate data and scale-up uncertainties. Hence it is stiH the usual practice to carry out tests on equipment to be sure of predictions. [Pg.139]

The dominant crystal size, is most often used as a representation of the product size, because it represents the size about which most of the mass in the distribution is clustered. If the mass density function defined in equation 33 is plotted for a set of hypothetical data as shown in Figure 10, it would typically be observed to have a maximum at the dominant crystal size. In other words, the dominant crystal size is that characteristic crystal dimension at which drajdL = 0. Also shown in Figure 10 is the theoretical result obtained when the mass density is determined for a perfectiy mixed, continuous crystallizer within which invariant crystal growth occurs. That is, mass density is found for such systems to foUow a relationship of the form m = aL exp —bL where a and b are system-dependent parameters. [Pg.348]

Drawdown time t = 3.38 h Shape factor = 1.00 Product size ... [Pg.1661]

FIG. 18-63 Calculated product -size distribution for a crystallizer operation at different fine-crystal-separation sizes. [Pg.1663]

A series of classification pockets, with decreasing quantities of hydraulic water in each, producing a range of product sizes. [Pg.1779]

The work index may be round experimentally from laboratoiy crushing and grinding tests or from commercial miU operations. Some rules of thumb for extrapolating the work index to conditions different from those measured are that for dry grinding the index must be increased by a factor of 1.34 over that measured in wet grinding for open-circuit operations another factor of 1.34 is required over that measured in closed circuit if the product size Xp is extrapolated below 70 [Lm, an additional correction factor is (10.3 + Xp)/l.l45X . Also for a jaw or gyratory crusher the work index may be estimated from... [Pg.1831]

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