Conveyor features

Belt Typ es The patented metal-belt type (Fig. ll-53a), termed the water-bed conveyor, features a thin wall, a well-agitated fluid side for a thin water film (there are no rigid welded jackets to fail), a stainless-steel or Swedish-iron conveyor belt floated on the water... 

The dual conveyor option becomes the most expensive primarily due to the cost of the conveyors and the additional excavation requirements to house the conveyors. Comparable results are attained for the remaining options as the extra expense of the slewing conveyor feature in the slewing conveyor options offset the cost of the additional chutes and shuttle car in the single conveyor shuttle car loading design. 

Conveyor-Belt Devices The metal-belt type (Fig. 11. 55) is the only device in this classification of material-haudhug equipment that has had serious effort expended on it to adapt it to indirecl heat-transfer seiwice with divided solids. It features a lightweight construction of a large area with a thin metal wall. ludirect-coohiig applications have been made with poor thermal performance, as could be expected with a static layer. Auxihaiy plowlike mixing devices, which are considered an absolute necessity to secure any worthwhile results for this seiwice, restrict applications. 

The Mix-R-Step type in Fig. ll-62e is an adaptation of avibratoiy conveyor. It features better heat-transfer rates, practically doubling the coefficient values of the standard flat surface and trebling heat-flux values, as the layer depth can be increased from the norm 13 to 25 and 32 mm (V2 to 1 and F in). It mav be provided on decks jacketed for air, steam, or water spray. It is also often apphcable when an infrared heat source is mounted overhead to supplement the indirect or as the sole heat source. 

Lift can usually be handled most economically by vertical or inclined bucket elevators, but when lift and horizontal travel are combined, other conveyors should be considered. Conveyors that combine several directions of travel in a single unit are generally more expensive, but since they require only a single drive, this feature often compensates for the added base cost. 

The continuous-flow conveyor is a totally enclosed unit which has a relatively high capacity per unit of cross-sectional area and can follow an irregular path in a single plane. These features make it extremely versatile. Figure 21-10 shows some typical arrangements and applica-... 

Figure 22-8 shows the features of a horizontal center-fed column [Brodie, Au.st. Mech. Chem. Eng. Tran.s., 37 (May 1979)] which has been commercialized for continuous purification of naphthalene and p-dichlorobenzene. Liquid feed enters the column between the hot purifying section and the cold freezing or recovery zone. Ciystals are formed internally by indirect cooling of the melt through the walls of the refining and recovery zones. Residue liquid that has been depleted or product exits from the coldest section of the column. A spiral conveyor controls the transport of solids through the unit. 

Industrial equipment is a continuing area of development for plastics. Pipes, pumps, valves and sight glasses, made from such materials as PVC, PTFE and poly-4-methylpent-l-ene, have become well established on account of their corrosion resistance. The nylons are used for such diverse applications as mine conveyor belts and main drive gears for knitting machines and paper-making equipment. These and other materials are widely used where such features as toughness, abrasion resistance, corrosion resistance, non-stick properties, electrical insulation capability and transparency are of importance. 

The basic features of the electric furnace are illustrated in Figure 25. The electric furnace is basically a conveyor belt system passing through a long rectangular... 

Elame propagation can also be stopped between process eqnipment handling bnlk solids and powders by jndicions selection and design of bnlk solids/powders conveying eqnipment snch as rotary valves (rotary airlocks) and screw conveyors. The mass of bnlk solids/powders contained in these items of eqnipment provide a tortnons path throngh which the gas and flame have to pass, and so can act as a material choke when certain design features are implemented. 

The ocean conveyor belt is one of the major elements of today s ocean circulation system (Broecker, 1997). A key feature is that it delivers an enormous amount of heat to the North Atlantic and this has profound implications for past, present, and probably future climates. 

Filling Conveyor. Filling line transfer system is an automatic, nonsynchronus, variable-speed drive unit complete with filling pallets and nests for the five different munitions filled and closed on the line. This unique system moves work pallets from station to station and provides accurate shot pin alignment for the work piece as various operations are performed, and features automatic acceleration and deceleration of the filling pallets. Operation is unusually smooth, quiet and safe. 

X-ray excited steady-state luminescence has been checked as a distinctive feature for the phosphorites, Karatau (Gorobets et al. 1997a). Sedimentary apatite (francolite) is not luminescent under X-ray excitation and red Mn " luminescence of dolomite was employed. As a result, concentration of MgO in the accepted fraction was lowered from 5.0% to 2.4%. The use of this method is limited because in many cases the X-ray luminescence of dolomite is very low or non-existent. Besides that, other minerals without luminescence come together with the accepted phosphate fraction, including sihceous shale, which is harmful for the following deep beneficiation. Thus new methods have to be developed for detection and content evaluation of dolomite in Florida phosphates on moving belt conveyors. 

Of special interest on multiple-spout conveyor-equipped fluidizers and on certain types of screw and belt filling machines is a combination operator s seat, bag rest, and tuck-in-sleeve work aid. This device places the operator in an optimum work position after filling, to allow easy and positive tucking of the sleeve. Extensive use of the polyethylene film internal sleeve, however, has reduced the significance of die tuck-in-sleeve feature. Several types of heat-sealable valve-bag sleeves are available, as is equipment for closing them automatically. These are used when even slight leakage of product from an internal sleeve bag is unacceptable. 

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