Conveyor installation

Conveyor installations maybe permanent or a combination of permanent and portable. The latter kind is often mounted on a bulk-deliveiy vehicle, which permits fast unloading into the customers silo by the carrier without effort or equipment from the customer. Controls range from simple motor starters and hand-connected hoses to sophisticated, microprocessor-elec tropueumatic control systems. 

Just at the time construction work in No. 20 District was coming to a close, agitation from the RAOC in favour of belt conveyors for ammunition transport was having some success. By way of experiment, the trough belt conveyor installed in the slope-shaft for waste disposal was converted to a flat belt to carry ammunition. Three additional Mccco conveyors from the batch purchased for assessment trials were installed in the district in time for the hand-over in September, 1939. 

Wood chips are reclaimed from the storage pile by chip dozers and deposited in reclaim hoppers adjacent to the wood pile. Steel grates above the hoppers prevent frozen chips or oversized objects from jamming conveyors or otherwise fouling handling equipment. Draft conveyors installed beneath the hoppers discharge chips to inclined belt conveyors which elevate the wood fuel to storage bunkers situated above the power plant boilers. Chips are continuously fed to the boiler feeders to provide adequate fuel supply. 

The hoisting option includes sinking costs for winches required to install ground support shaft steel. Analogous functions for the conveyor installation are included in the conveyor installation and are accomplished with the raise climber. 

On the feed side of the crusher, fine material sticking to the apron conveyor and falling off It on the return run is removed by a scraper conveyor installed in a concrete trough in the foundation slab or otherwise, if accessible space is required under the apron conveyor, in a steel trough mounted directly under the latter. As an alternative solution the product removal conveyor on the discharge side of the crusher may be extended rearwards to underneath the throw-off end of the feed apron conveyor and thus catch the material falling off. In that case a separate scraper conveyor can be dispensed with. 

One of the best actions is to use a similar chain conveyor installation that has given good performance and service life. One should contact an engineering steel chain manufacturer for help in selecting a conveyor. Much experience is usually needed to make a good selection. 

All chain is made to length tolerance specifications. The matching of strands ensures that sections of chain, with lengths at opposite ends of the tolerance range, are not placed opposite one another in the conveyor installation. 

Process industries frequently need to weigh and control the flow rate of bulk material for optimum performance of such devices as grinders or pulverizers, or for controlling additives, eg, to water suppHes. A scale can be installed in a belt conveyor, or a short belt feeder can be mounted on a platform scale. Either can be equipped with controls to maintain the feed rate within limits by controlling the operation of the device feeding the material to the conveyor. Direct mass measurement with a nuclear scale can also be used to measure and control such a continuous stream of material. 

Automatic discharging suspended magnets can be operated transversely (Fig. 2) or parallel to conveyor flow (Fig. 3b and 3c). Because the tramp iron must be attracted from a buried location and turned 90° from the movement of the conveyor belt, a larger and stronger magnet is required for a transverse installation. In some instances, the material handling layout, or desired operation location, dictates the use of the transversely mounted magnet. 

Any type of sohds conveyor may be suitable for recycle mixing however, the most universally applicable is the double-shaft pug-miU-type paddle mixer. This conveyor or mixer should be insulated to prevent excessive heat losses from the hot, dry recycle product. To ensure uniformity in the recycle operation, a surge storage reserve of recycle sohds should be installed for startup purposes and in the event of interruption of product discharge from the cyhnder. In recycle operations, 50 to 60 percent product recirculation is found economical in many instances. 

Operating costs will include 5 to 10 percent of one worker s time, plus power and fuel required. Yearly maintenance costs will range From 50 to 10 percent of total installed costs. Total power for fans, dr er drive, and feed and prodirct conveyors will be in the range of 0.5 D to 1.0 D". Thermal efficiency of a high-temperature direc t-heat rotary dryer will range from 55 to 75 percent and, with steam-heated air, from 30 to 55 percent. 

Conveyor-belt speeds above approximately 300 ft per minute (1.5 meters per second) impart sufficient momentum to material discharging at its head pulley to cause lifting of material streams in a trajectory from the head pulley. A trajectory is illustrated in Fig. 19-7. Blades of the sample cutter are positioned to intersect the trajectoiy. See Fig. 19-7 for an example of a linear-traversing bottom-dump cutter installation. Calculation of trajectory profiles are described in the Conveyor Equipment Manufacturers Association publications and similar references. 

The number of speed reduetions is another way to classify conveyor drives. Most common of the speed-reduction methods is the two-step system, in which the motor is coupled to a speed reducer and the slow-speed shaft of the reducer is connected to the conveyor-drive shaft by a V belt or a roller chain. The second reduction not only permits the use of a simpler speed reducer but also allows a more flexible layout of the motor and reducer mounting plate. On many installations this eliminates the need for a specially designed drive mount. 

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