Screen reels

The ordinary sizes of centrifugal reel range from 24 to 39 in. in diameter and from 5 to 8 ft. long. The 24-in. reel runs from 180 to 200 r.p.m. The reel shown in Fig. 18 runs from 100 to 130 r.p.m. and is made in diameters ranging from 24 to 30 in. The figure shows a vane revolving contrariwise to the motion of the screen. 

Reel chop from the field can come in 1" to 4" lengths with bulk densities of 2 to 4 Lb/CP (32-64 Kg/ia ). For straws we found Japanese feed markets required 2" to 3" lengths (3 Lb/CP, 10 HP Hr/Ton) but domestic feed, fuel and fiber products could be made using a 3/8" screen (5 Lb/CP - 20 HP/Ton/Hr). Hammermills are better than shredders. Tub grinders have low efficiency and are best for mixing. Cornstalks, husks and leaves can be cubed readily using a 3/4"-1 " screen. 

Here the plate is on a curved cylinder and operates as in Figure 16.4. Speeds are high 8,000 to 30,000 revolutions per hour. Feed is usually reel, but can be sheet. Plate cost varies—can be around 200-250 per col our (depending on size and screen). Main applications of letterpress are for the printing of paper and board. 

The diluted stock may then be pumped by the fan pump through a series of cleaners and into the machine headbox. An inlet distribution header spreads the stock flow evenly over the width of the headbox. The flow is stabilised by the headbox and passes from the headbox through an adjustable orifice plate called the slice. It is discharged onto the moving wire screen (which is usually of plastic construction), dewatered by a series of devices called table rolls, foils and flat boxes leaves the wire as a formed web of paper. It is further dewatered and dried in the succeeding operation before being wound on the reel at the dry end of the machine. 

Dredges — Cable, reel and conveyor screen drives... 

Conveyors, cable reels Jigs, screens Fans and blowers... 

Upon exit from the machine, the laminate is interleaved with paper to protect the domes, and then re-reeled. Currently, pick-and-place, screen printer, dispenser, and reflow specialists are working in partnership to produce a fully integrated flowline concept for dome processing and other reel-to-reel applications. The reflow machine is huilt on the same base as the pick-and-place machine (Figure 2) for placement of sticky foils onto PCBs. 

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