What is pre split in mining?
Pre-splitting can be defined as ‘a technique using lightly charged, closely spaced holes to induce a fracture plane along a required design profile, which isolates the rock to be blasted from the surrounding rock mass’. The holes are generally fired instantaneously well in advance of any blasting in the adjacent rock.
What is back break in mining?
… Backbreak is one of the adverse impacts of blasting operations that causes the instability to mine walls, falling of equipment, improper fragmentation, reduced efficiency of drilling and uneven burden for next blast.
What is Presplitting blasting?
Presplit blasting involves drilling a single row of holes along the back of the final excavation zone . Unlike smooth wall blasting, the presplit holes are fired on the first delay of the production blast. The presplit technique is the most commonly used controlled blasting technique for surface operations.
How are explosives used in mining?
Holes are drilled into the rock to be broken. A portion of each hole is filled with explosives. The top portion of the hole is filled with inert material called stemming. The explosive in each hole is initiated with detonators or blasting caps.
What is smooth wall blasting?
A technique used in surface and underground blasting in which a row or closely spaced drill holes are loaded with decoupled charges (charges with a smaller diameter than the drill hole) and fired simultaneously to produce an excavation contour without fracturing or damaging the rock behind or adjacent to the blasted …
What is cast blasting?
The Cast Blasting method is based on the use of explosive energy to break and move a rock mass directly into a berm (void created in a previous pit) thus minimizing the use of mechanical mining equipment (Figure 6), including draglines.
What explosive are used in mines?
Ammonium Nitrate Fuel Oil
The base explosive used in mining is called Ammonium Nitrate Fuel Oil (ANFO). Oxides of Nitrogen can be inadvertently generated as fume by the incomplete detonation of explosives during a blast.
Why do miners use explosives?
While cognizant of the inherent dangers, explosives are essential in breaking rock. Surface mines in the coal and metal/nonmetal sectors rely extensively on explosives to uncover mineral deposits. The mining industry considers blasting an essential component for the success of their operations.
What is the process of blasting?
blasting, process of reducing a solid body, such as rock, to fragments by using an explosive. Conventional blasting operations include (1) drilling holes, (2) placing a charge and detonator in each hole, (3) detonating the charge, and (4) clearing away the broken material.
What is control blasting technique?
Controlled blasting is a technique of blasting, which is used to reduce the amount of over break and to control ground vibrations. The different types of controlled blasting techniques are pre-splitting, smooth blasting, line drilling, perimeter blasting, and cushion blasting.
What muffled blasting?
Description. Muffle blasting is used in opencast mining to prevent fly rock near the populated and roadways area.
What is pre-splitting in open pit mines?
, N.- A. Askarnejad Pre-splitting is a controlled blasting technique with applications in open pit mines. The main excessive ground vibrations; and filtering the effects of explosive gases from production blasting. surface between the main blasting pattern and open pit final walls. In this study, a large open pit and cost effective experiments.
What is pre-splitting?
Pre-splitting is a controlled blasting technique with applications in open pit mines. The main excessive ground vibrations; and filtering the effects of explosive gases from production blasting. surface between the main blasting pattern and open pit final walls. In this study, a large open pit
What is pre-splitting in controlled blasting?
Design of controlled blasting (pre-splitting) in Golegohar iron ore mine, Iran (S. R. Dindarloo et al.,2015). … The pre-splitting holes aim to extract the rock mass in order to create a smooth face.
What is the purpose of pre-splitting holes in a rock?
… The pre-splitting holes aim to extract the rock mass in order to create a smooth face.