Flakers

Another product is made with strands produced by flakers, having dimensions of about 0.8 x 13 x 300 mm (0.030 x 0.5 x 12 in.). The strands are dried and then coated with isocyanate adhesives. The strands are formed into mats with unidirectional orientation and pressed in a steam-through press. The large panels are then sawn into dimension lumber sizes. 

Several plants employ cooled-belt flakers. These consist of flexible steel belts, ca 1-m wide and up to 50-m long, that have short mbber skirting at the edges. Molten pitch flows from a thermostatically controlled tank over a weir to give a flat thin sheet on the belt, which is cooled from below by water sprays. At the end of the belt, the solid pitch is broken up by rotating tines. The pitch flakes are drained and transported to a covered storage silo by belt conveyor, during which time the surface moisture evaporates. 

Another major type of equipment among the family of crystallizers is the flaker. The flaker is a piece of equipment that is used for the production by chilling of flakes, chips, large crumbs, or crystals from a hot, concentrated solution or melted crystals. 

Solid was scraped off a flaker—a rotating steel drum—by a steel knife. After the knife was replaced by a plastic one, an explosion occurred, probably because more dust was produced [14]. 

Table flaker — a flat metal sheet with turned up edges and jacketed on die under side for coolant flow. It is used for 1 inch thick slabs... 

A brief description of a single-drum flaker is given, together with Fig 6, on p D1560-L of Vol 5 of Encycl and of a double-drum flaker, together with Fig 7, on the same page Ref Perry (1963), p 11 42-3... 

Under this term are known devices in the form of rotary drums for prepg various substances in the form of small scales (flakes). Such drums, known as flakers are used in the manuf of TNT. Flaking can also be done by using water-cooled belts, such as in the Stengel process for making flaked Ammonium Nitrate. This process is briefly described in this Encycl, Vol 1, p A315-R. 

In the case of TNT, crystallization was used in the USA prior to WWI1, but during the war this method was practically replaced by flaking on rotary drums. It must be noted that "flakers , such as now used, function also as driers ... 

A typical flaker , such as used in manuf of TNT and some other HE s consists of a horizontal, hollow, metallic (usually cast-iron), water-c ooled, drum, with hollow truoions mounted in bearings. It is given in Perry, pll64-L as Fig 68 and reproduced here as Fig 6. The lower part of drum dips into molten material located in a hollow, steam-... 

Some devices which produce flaked material are listed by Perry as "driers , because their principal purpose is to dty the materials. They resemble in appearance the flakers, but their hollow drums are heated. Some of these devices are described under "Drying and Driers ... 

Flakers are also described by Riegel (Ref 1, pp347—50) and a rotary, single-drum flaker is shown in Fig 271, p348 Refs 1) Riegel (1944), 347—50 2) Perry... 

Explosives which are produced in flaked form (like TNT) lose moisture during the process of flaking (See under "Drum, Flaker ) Methods used for drying expls in Germany during WWII were described by Glucklich (Ref 6). Holland-Merten (Ref 15) described vacuum drying techniques used in explosives industry... 

Ushakumari et al. (2007) developed a process for the preparation of expanded ragi. After parboiling and decortication, the grains were conditioned to 40% moisture, flattened in a roller flaker, and then toasted in salt maintained at 220-225 °C for 6 s. Shape factor (ratio of measurements on two peripendicular axes), the expansion ratio (ratio of the volume of expanded millet to that of the decorticated millet of equal weight), apparent bulk density (volume of known weight of expanded millet), and sensory characteristics were the criteria used. The optimum conditions to prepare a product with the highest expansion ratio was then determined. 

Chippers and flakers are the most widely used knife reduction systems. Chippers produce coarse particles from roundwood, slabs, plywood trim, and other residues from the primary wood industry. Chippers are the initial reduction step in particle preparation and further size reduction is necessary to produce a satisfactory particle. The chipping operation may be located at the particleboard plant or the chips may be delivered to the plant from an in-woods chipping operation, a chip-n-saw mill, or from another primary wood industry. Screening after the chipper removes all fines and oversize chips before they enter the secondary reduction step. Oversize chips are recycled to the chipper and fines are normally sent to the boiler for fuel. 

Pastes and melts are spread as a thin film on a surface where they are dried and cooled, respectively. Subsequently scraped off to yield solid product. Drum drying, flaking, melt cooling, endless belt processing, slating, pastille formation. Drum dryers, drum flakers, endless belt systems... 

Heat may be transferred directly as in the burning of solid fuel mixed with the particulates in the sintering of ores or indirectly as in the combustion of fuel to produce hot gases in pellet hardening. External heat transfer may also take place across a metallic surface as in drum and belt driers and flakers. 

Fig. 6.5. A typical drum flaker operation. (Courtesy Envirotech Corporation.)...

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