Sliding gates

Blast gates Adjustable sliding gates (dampers) on extract ductwork used to balance the system. 

A variety of fast-acting valves are available, inclnding slide gate, flap (bnt-terfly), and float (poppet) valves. Slide gate and flap type valves are actn-ated (closed) npon a signal from a detector (sensor) in the pipeline between two items of interconnected process eqnipment. The detector sends a... 

FIGURE 3-14. Fast-acting slide gate valve isolation system (NFPA 69). 

Fig. 2.55. Freeze drying plant, type CQC, as shown in Fig. 2.53. In this plant, two carriers are moved in parallel through the tunnel. The photograph shows the two heated shelves systems. The sliding gate valve is located in the large extension on the left side. In this plant approx. 5000 tonnes of freeze dried coffee granulate can be produced annually (photograph ALD Vacuum Technologies GmbH, D-63526 Erlensee).

The modulus of elasticity (MOE) is related to the strength and can be used as a nondestructive quality control test on high cost special refractory shapes such as slide gate valves employed in the pouring of steel (qv). The slide gate type must be selected to ensure chemical compatibility and it must be used in a way to reduce thermal shock. The performance of a properly selected and used slide gate is direcdy related to its strength and therefore predicted by its MOE. 

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. 

Solids Metering The control valves described earlier are primarily used for the control of fluid (liquid or gas) flow. Sometimes these valves, particularly the ball, butterfly, or sliding gate valves, are used to throttle dry or slurry solids. More often, special throttling mechanisms such as venturi ejectors, conveyers, knife-type gate valves, or rotating vane valves are used. The particular solids-metering valve hardware depends on the volume, density, particle shape, and coarseness of the solids to be handled. 

High-pressure process streams can be throttled by the positioned disc-type slide gate valve. 

The tendency with production units is to provide blowers of sufficient capacity to allow satisfactory removal of a wide range of compounds, many with Henry s constants much lower than that of TCE. Erequently, a sliding gate valve is provided as a means of reducing the air... 

The recycled silica sand entered the combustor through a 7.62 cm diameter pipe located approximately 10 cm above the distributor plate. This pipe was installed at an angle of approximately 20 degrees to the combustor and was equipped with a slide gate valve to regulate the sand flow from the EHE into the combustor. 

Several types of valves are used. The tunnel diverter valves allow the use of multiple supply or receiving lines. The A valve diverts the material stream to one of two destinations. The aeropass valve separates air from the material. The slide gate valve opens or closes to control flow. These valves can be either manual or automatic. ... 

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