Vibratory conveyors

Unlike the chute which must be set at a relatively large declined angle to ensure that the bulk will slide against the chute surface, most vibratory conveyors are used for horizontal or near horizontal conveying with the exception of vibratory elevators which will be discussed later. They can convey on moderate (about 15°) upward and downward slopes. It is possible to design in multiple inlets and outlets to the conveyor. The outlets can either be a series of gates in the trough, or otherwise the stream can be split in some way to provide a number of 

In order that any bulk material resting on the trough does not simply follow the same motion with no net transport, the material has to be thrown forward, that is it has to have a sufficient vertical acceleration to overcome gravity and be free of the trough surface. This condition can be expressed as  

The ratio of vertical acceleration to g is known as the dynamic material coefficient or the throw factor T. 

Another commonly quoted value is the ratio of the maximum trough acceleration to g (as opposed to the previously defined vertical acceleration ratio), K, the dynamic machine 

This brings about efficient transport and low rates of particle damage and/or trough wear in fact, vibratory conveying can be a very gentle mode of transport. There are limitations due to the practicalities of large accelerations and typical values for accelerations and amplitudes are given in Table 6.1. 

---

Vibratory-Conveyor Devices Figure 11-62 shows the various adaptations of vibratoiy material-handling equipment for indirect... 

The heavy-duty jacketed type (Fig. ll-62a) is a special custom-built adaptation of a heavy-duty vibratory conveyor shown in Fig. 11-60. Its apphcation is continuously to cool the crushed materi [from about 177°C (350°F)] produced by the vibratoiy-type caster of Fig. 11-53. It does not have the liqmd dam and is made in longer lengths that employ L, switchback, and S arrangements on one floor. The capacity rate is 27,200 to 31,700 kg/h (30 to 35 tons/h) with heat-transfer coefficients in the order of 142 to 170 W/(m °C) [25 to 30 Btii/(h ft °F)]. For heating or drying applications, it employs steam to 414 kPa (60 IbFin ). 

FIG. 11-62 Vibratory-conveyor adaptations as indirect heat-transfer equipment, a) Heavy-duty jacketed for bqiiid coolant or high-pressure steam, (h) Jacketed for coolant spraying, (c) Light-duty jacketed construction, (d) Jacketed for air or steam in tiered arrangement, (e) Jacketed for air or steam with Mix-R-Step surface, Coutiesy of Jeffrey Mfg. Co.)... 

Open storage pits for unprocessed wastes, storage bins and silos for processed wastes transfer equipment including front-end loaders, metal and rubber belt conveyors, vibratory conveyors with unprocessed wastes, pneumatic conveyors, and screw conveyors with processed wastes... 

Belt conveyor Apron conveyor Right conveyor Drag chain En masse conveyor Screw conveyor Vibratory conveyor... 

These study findings were employed to optimize Primac/ Telemac sprinkler systems in all CASBL vibratory conveyors. 

The Mix-R-Step type in Fig. 1 l-62e is an adaptation of a vibratory 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 normal 13 to 25 and 32 mm to 1 and 1V4 in). It may be provided on decks jacketed for air, steam, or water spray. It is also often applicable when an infrared heat source is mounted overhead to supplement the indirect or as the sole heat source. 

Vibratory-Conveyor Devices Figure 11-62 shows the various adaptations of vibratory material-handling equipment for indirect heat-transfer service on divided solids. The basic vibratory-equipment data are given in Sec. 21. These indirect heat-transfer adaptations feature simplicity, nonhazardous construction, nondegradation, nondusting, no wear, ready conveying-rate variation [1.5 to 4.5 m/min (5 to 15 ft/min)], and good heat-transfer coefficient—115 W/(m -°C)... 

Designed to sort compacted bottles, the Poly-Sort system employs conveyors for singulation, and two devices for color and chemical composition identification. A vibratory conveyor singulates bottles a read conveyor transports bottles to an ultrasonic sensor that detects their position a near-infrared system detects the resin type a camera detects the color of the container a computer integrates data and makes an identification air jets divert bottles to the appropriate segregation conveyor or hopper. 

Bales weighing 600-800 lb, collected by commercial haulers, film-generating business, or the solid-wastes-handling industry, are first fed into a breaker-shredder. The shredded material then passes over a vibratory conveyor or through metal-detection systems to remove ferrous and nonferrous contaminants. Film is next sent to a sedimentation tank for removal of rocks or dirt before going into the granulator... 

Vibratory conveyors are limited to straight distances, usually horizontal, up to 100 ft, but are not suited for fine particles less than 100 mesh in size. Solids must be free flowing, but temperatures up to 250°F can be handled. Widths range from 1 to 36 in. with pan heights to at least 5 in. Experiments are usually necessary to properly size a vibratory conveyor. For an 18-in.-wide conveyor with a 5-in. pan height and a 20-ft length, a typical mass flow capacity is 70,000 Ib/hr or 700 ft /hr for solid particles having a bulk density of 100 Ib/ft. ... 

---