the drum cutter can break the hard rock?
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Update time : 2019-03-05 14:45:26
Robustness of rocks:
Platts hardness Representative rock
F=20 The strongest, dense, tough quartzite, basalt and a variety of other particularly strong rocks.
F=15 Very strong granite, quartz porphyry, siliceous schist, stronger quartzite, the strongest sandstone and limestone.
F=10 Dense granite, very strong sandstone and limestone, quartz veins, strong conglomerate, very strong iron ore.
F=8 Rugged sandstone, limestone, marble, dolomite, pyrite, not solid granite.
F=6 Relatively strong, general sandstone, iron ore.
F=5 Relatively solid sandy shale, shale sandstone.
F=4 Medium sturdy Solid muddy shale, not strong sandstone and limestone, soft gravel.
F=3 Medium sturdy Various unsturdy shale, dense marl.
F=2 Soft shale, very soft limestone, chalk, salt rock, gypsum, anthracite, broken sandstone and stony soil.
F=1.5 Relatively soft gravel soil, broken shale, bonded gravel, gravel, strong coal, hardened clay.
F=1 Soft compact clay, soft bituminous coal, strong impact soil layer, clay soil.
F<1 Soft sandy clay, gravel, loess, Soil humus, peat, soft sandy soil, wet sand, gravel accumulation, loose soil, mined coal and etc.
A quantitative indicator of the robustness of a rock.
In the long-term practice, people realized that some rocks are not easy to break, and some are difficult to break. Rocks that are difficult to break are generally difficult to rock, difficult to blast, and their hardness is relatively large, in general, it is more sturdy. Therefore, people use the concept of rock solidity to indicate the difficulty of rock breaking.
The size of the sturdiness is expressed by the coefficient of firmness, also known as the hardness coefficient, also known as the Platts hardness factor f.
Robustness factor f=R/100 (R unit kg/cm2)
Where R is the unidirectional ultimate compressive strength value of the rock standard specimen.
The commonly used Platts rock classification method is to classify rocks according to the solidity coefficient.
Such as:
1 Extremely strong rock f=15～20 (sturdy granite, limestone, quartzite, etc.)
2 Hard rock f=8 ～10 (such as unsturdy granite, strong sandstone, etc.)
③ medium solid rock f = 4 ~ 6 (such as ordinary sand, iron ore, etc.)
④ not solid rock f = 0.8 ~ 3 (such as loess, only 0.3)
The robustness of the rock is also a property against external forces, but its strength with the rock is two different concepts.
Strength refers to the performance of the rock against unidirectional action such as compression, stretching, bending and shearing. The external force resisted by the sturdiness is a comprehensive external force. (such as resistance to sputum, manuscript, mechanical breakage, the combined force of explosives).
