Scraper conveyors

A static leaf filter is used for cleaning machine tool coolants. These are used on the suction side of a pump circulating system, with the same pump employed for withdrawal of the filtrate as for backdushing the filter elements. SoHds in this case are removed from the sump by a scraper conveyor. 

When the falling stream is more than 1 ft thick or is more than about 2 ft wide, the forces involved tend to be greater than can be resisted with handheld equipment, and simple mechanical devices are often useful. A pivoted scoop with the necessary mechanical advantage is useful, and slide gates (a dropout section at the bottom of a scraper conveyor) or a flop gate in a vertical chute are other possibilities. In the event that such alternatives are not feasible, partial stream cuts are permissible, but the reliability of the sampling is reduced. To combat any reduction in the reliability, partial stream cuts need to be made systematically at different points in the stream so that all parts of the coal stream are represented proportionately. 

It makes the rear scraper conveyor to locate in a larger space that adding a vice support behind the normal (host) support. See Figure 6. 

The coal-raking system with tilt scraper and symmetric wheels is put under the low coal-caving window, rakes the cracking drop-coal on the floor into the high troughs of scraper conveyor s head and tail. 

The coal-caving system with unsymmetrical pair open troughs (one longer and one shorter) is designed in the middle of support s top beam. The open troughs joins to support s top beam in the way of sliding round, in order to adapt to the continuous caving of top-coal at different location of scraper conveyor. 

The single open directional moving baffle plate is installed at the side of shorter trough, in order to improve the efficiency of coal loading, while at the same time the fixed baffle plate is installed at one trough ledge of scraper conveyor. See figure 8 shown. 

The Mining Face uses SGZ730/400-type scraper conveyor, the roadways and transportation lanes... 

For this purpose, a chamber filter press with a voliune of 2 m and a sludge collection tank (30 m in volume) with an agitator were installed. The sludge was passed from the scraper conveyor directly into the storage tank and preconditioned with lime. 

Coal mine has humidity, high temperature, flammable gas, coal dust and other big issues, in which the boring machine, scraper conveyor, belt conveyors, fans, pumps, hoists and other equipment should be driven by explosion-proof three-phase asynchronous motors. Whats worse, the universal converters are forbidden to use directly in these occasions, and these equipment s control methods are direct start and mechanical speed control, which will cause a great Impact to the current and voltage of the power supply system. ... 

Depending upon how chain and moving elements are mounted for a specific duty, several types of chain conveyors can be obfained. Scraper conveyors will have the moving element, or flight, fitted perpendicular between two strands of roller chains, while apron conveyors will have fhe moving elements, or pans, overlapped and mounted on the same plane of roller chains forming a continuous "apron." When buckefs are fixed to two strands of roller chains mounted on a steep-sloped or vertical structure, elevation of bulk solids can be possible in the so-called bucket elevators. 

Scraper conveyors (a) horizontal conveyor and (b) Z-type conveyor-elevator. 

The main variables for selection and design of scraper conveyors are the capacity and the power. The capacity of horizontal scraper conveyors loaded with materials of approximately 800 kg/m bulk density, has been calculated and is presented in Table 3.8. The theoretical horsepower requirement P for flight conveyors can be determined from the following equation ... 

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. 

ASME standard B29.15 lists a few of the more popular steel roller conveyor chains and attachments. But manufacturers produce many more models of this type of chain and furnish them with a wide variety of attaehments. These chains are mainly used in conveyors with flights or slats, although they are also sometimes used in bucket elevators and scraper conveyors. 

The material conveyed and how it is to be placed on and takm off the conveyor really dictates the type of conveyor to be used. For example, if the materials to be handled are individual large objects, which can be slid on and off the conveyor, a floor, carrier, or slat conveyor usually will be used. If the material to be handled is a bulk material, sueh as eoal or sawdust, or even logs, the material will be carried by the conveyor or pushed along in a trough by a drag or scraper conveyor chain. 

Scraper conveyors are widely used to handle bulk materials such as coal, ashes, potash, lime, grains, and other bulk materials. As shown in Figure 9-25, short, heavy-duty scraper conveyors are used to load elevator scrapers used on construction jobs, where large amounts of dirt must be moved. 

Assembly line conveyor Drag and scraper conveyors Apron conveyor... 

The most common uses for roller chains probably are in carrier and slat conveyors. RoUct chains are seldom used in apron or scraper conveyors that carry bulk materials. This is because the small clearances in roller chain easily become packed and clogged with the loose conveyed matmal. If roller chain is used in one of these conveyor types, the chain should be well shielded from the loose material. 

This chapter does not cover roller chains conveying bulk materials in drag or scraper conveyor applications. The designer should consult an ACA roller chain manufacturer for help with these applications. 

The matmal eonveyed is pushed, scraped, or othrawise slid along a conveyor deck. The chain does not support the material. Ihisher and scraper conveyors fit in this category. 

Top heating device Casting mould Scraper conveyor... 

F. The slagged ash drops into a water seal, from which it is removed by a continuous scraper conveyor. The high temperature reportedly results in production of a gas mixture rich in the desirable constituents of CO and Hj, with no methane and only limited amounts of COj. Characteristically, coal yields a gas of 50 to 55 percent CO and 30... 

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