blasthole
Quick Summary
A blasthole is a hole drilled into a solid material, such as rock, for the insertion of an explosive charge. This process is fundamental to blasting operations, which are used to break down materials for mining, demolition, and excavation.12
The blasting process involves drilling blastholes, placing explosive charges and detonators within them, and then detonating the charges. The explosion releases immense pressure, shattering the surrounding material and creating cracks. These cracks extend, causing the rock to break and move forward, especially when near an exposed surface.1
Blastholes are strategically placed to maximize the efficiency of the explosive, ensuring uniform fragmentation. Charges are often fired in a predetermined sequence with slight delays to create new exposed faces for subsequent blasts, breaking large bodies of rock effectively. This technique is widely used in mining for coal, ore, and stone, as well as for demolishing buildings and excavating foundations.1
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miningHorizontal openings: driftsA pattern of parallel blastholes is drilled into the rock face at the end of the drift. The diameter of these holes ranges from 38 to 64 mm (1.5 to 2.5 inches), but in general one or more larger-diameter uncharged holes are also drilled as part of the initial…
Read MoreA pattern of parallel blastholes is drilled into the rock face at the end of the drift. The diameter of these holes ranges from 38 to 64 mm (1.5 to 2.5 inches), but in general one or more larger-diameter uncharged holes are also drilled as part of the initial…
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coal miningDrilling and blastingBlastholes are generally drilled from the surface, are vertical, and vary in diameter from 25 to 100 centimetres. In some mines, horizontal holes are drilled into the overburden with the drill sitting on the coal surface. The holes are charged with explosives that are based…
Read MoreBlastholes are generally drilled from the surface, are vertical, and vary in diameter from 25 to 100 centimetres. In some mines, horizontal holes are drilled into the overburden with the drill sitting on the coal surface. The holes are charged with explosives that are based…
Read More