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Contents
 arrow Introduction + Help
arrow Air Pollution
arrow Blasting
arrow Cultural Heritage
arrow Ecology + Biodiversity
arrow Geodiversity
arrow Nature Conservation
arrow Noise
arrow Planning
arrow Quarry Fines + Waste
arrow Restoration + Rehab
arrow Social + Community
arrow Transport + Traffic
arrow Visual + Landscape
arrow Water
 arrow Industry Information
 arrow Production Technology
 arrow Case Studies
 arrow References
 arrow Updates (01/01/2010)

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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Tensile fracture
Fracture in rock that forms and propagates parallel to the direction of the maximum compressive stress.
Tensile
The stress of stretching or elongation. It can be thought of as negative compression.
Tertiary crusher
The final crushing stage before other processing options are undertaken. Typically reduces the size to below 20 mm.
Thickener
This is a mechanical device for increasing the solid/water ratio in a slurry. It consists of a large circular tank with rotating stirring arm. Solids settle and are removed as an underflow while clarified water overflows
Throw
The amount of movement between the moving and stationary crushing surfaces is known as the throw of the crusher, This applies to jaw and cone crushers.
Tillage
In conservation tillage, crops are grown with minimal cultivation of the soil. When the amount of tillage is reduced, the stubble or plant residues are not completely incorporated, and most or all remain on top of the soil rather than being plowed or disced into the soil.
Tip speed
The relative velocity at the end of the rotor in an impact crusher, within the range 35 to 90ms-1.
Toggle
Component of the actuating mechanism of a jaw crusher.
Toggle plate
The bottom of the pitman (jaw) is braced with a cast steel or iron toggle plate; this is often hydraulically controlled to alter the crusher product outlet and also acts as a release mechanism for 'uncrushable' material such as tramp iron.
Tooth profiles
These are the different design of liner plates in jaw crushers. They may have a standard 'Z-type' (symmetrical, flat corrugation), NC (non-choke), CC (coarse corrugation) and WW (wide wave) profile.
Top-soil
The uppermost layer of soil, rich in organic matter and forms of life.
Trail dredging
Extraction of marine aggregates: a suction pipe is pulled across the seabed at a slow speed. This extracts material in a shallow trench 2.5m wide by 0.25m deep; it allows working of relatively thin deposits.
Tramp Iron
Bolts, shovel teeth, picks and other uncrushable metal that is often present in crusher input material.
Transfer
Movement of material from one part of the process plant to the next.
Transfer Functions
This is a mathematical procedure which attempts to define the relationship between the values recorded at two different points, the purpose being to be able to predict the values at one, given the values at the other. This can be a simple factor for the PPV values (e.g. the values at point B is always approximately twice that at point A) or it can be more complex and seek to predict the entire seismic signal. Any Transfer Function requires a good set of data.
Transpiration
Process by which water that is absorbed by plants, usually through the roots, is evaporated into the atmosphere from the plant surface, such as leaf pores.
Type-I sub-base
Layer of granular aggregate used in road construction below the roadbase. The specification and thickness varies with the intended application.