blasting of cornices increases efficiency, boring holes along the presumed tension line exposes the ava-lanche blaster to considerable danger. Safety in borehole blasting depends critically on: 1. The blasting crews ability to judge correctly the safe working line. techniques for working with this high explosive (See Chapter 5 - Detonating Cord)..

Open Pit Mining | IntechOpen

2.2 Drilling and blasting. The ore deposit can be mined by means of drilling and blasting in order to fracture the rock into a loadable size. Blasting parameters should be matched with mechanical machines for drilling of blast holes and charging of explosives. Blast holes are drilled in well-defined patterns, which consist of several parallel rows.

25.3 Crushing and milling | Mining of mineral resources ...

Holes are drilled in the rock and explosives, like dynamite, are placed inside the holes to blast the rock into pieces. The pieces are still very large and extremely heavy. The rocks are loaded onto very large haul trucks and removed. Sometimes the rocks (ore) are crushed at the mining site to make them easier to transport.

Types of Underground Mining Method Comparison

The cost of mining is low, because a large percentage of the ore is broken with little or no blasting, and the amount of timber used is small. A large output is possible. A large percentage of the ore can be saved. The ore can be kept freer of waste than in block caving. Disadvantages: It is limited in application to certain ores.


In normal blasting all holes do not blast at the same time. ... A new iron ore deposit is to be worked by surface mining methods with 15 m benches using 150 mm diameter blastholes. Since the prevailing condition is dry rock, it has been decided to …

In-Situ Leaching & Borehole Mining

In this case, one potentially feasible mining method is to enter the ore body and excavate swell space to receive the remaining rock mass which is blasted. Extraction proceeds on a hybrid scheme where the rich portions of the ore body are mined conventionally and the leaner portions are exploited with the in situ technique. Shallow Deposits

Open-pit Mining - Mining North Works

The open-pit mining cycle includes drilling ore and waste rock, loading drill holes with explosives, blasting, ore loading and hauling to stockpiles for processing, waste rock loading and hauling to the waste rock storage pile. Occasionally, drilling and blasting ore is not required and can simply be removed by what is known as free digging.

Drilling & Blasting of Underground Stopes

Blasting in stopes is designed not only to break the ore from the solid but to obtain its proper fragmentation, and the explosive should be selected and the holes loaded with this in mind. Methods of pointing and loading the holes that result in throwing down large slabs or blocks of ore without proper fragmentation are not efficient.

Choice of Method - Welcome to the Narrow-Vein Mining Project

Shrinkage mining is practised in ore zones that are steeply dipping and are continuous along strike. When there is not enough continuity, the cut-and-fill mining method is selected. Panel stoping is necessary in areas of the mine where the ore …


In all these methods, there is a need to dislodge the ore or mineral deposit from the main body of the rocks. Dislodging requires heavy energy application and machineries. To simplify the work,...

Drilling patterns - QueensMineDesignWiki

This type of blast design is typically used for expanding a previously excavated drift to accommodate more space or to correct a poor blast. Therefore, they are generally shallow blasts along a length of a wall. This blast pattern is a variant of the fan cut but all of the holes are angled along the length of the wall that is to be excavated.

Explosives Engineers' Guide - Dyno Nobel

Presplit blasting Spacing = Hole diameter x 12 Burden = 0.5 x production blast burden (B) Uncharged length at top = 10 x D Powder factor = 0.5kg per square metre of face Do not stem holes. Fire all holes on the same delay, or in groups of ≥ 5 holes Smooth blasting Spacing = 15 x Hole diameter (hard rock) 20 x Hole diameter (soft rock)

Vertical Pit Mining-An Alternative to Open Pit Mining for ...

Vertical Pit Mining-An Alternative to Open Pit Mining for Massive/Shallow Orebodies P. J. Terbrugge1, R. Armstrong1 1SRK Consulting ... cycle time for anchor installation was four days from the time the anchor was installed in the hole, ... with ore from the blast muck pile loaded directly into the kibble and hoisted to


Shallow holes = 1 to 2 External loads = .3 Tons of Rock = Powder Factor ... The economic analysis of the use of explosives is an important part of blasting operations in mining and construction. Explosives are energy, and the efficient use of this energy is a major factor in keeping rock blasting ... total costs encountered in breaking, moving ...

1. Introduction

use of large diameter blast holes in shallow faces prevents the efficient charge distribution while small diameter blast holes in high faces can be ineffective due to effect of blast hole deviation. 2.2.3 Burden It may be defined as the shortest distance to relief at the time the hole is detonated in any blasting operation.

Cutting work of shallow hole retention method

1 In the stage transport lane, hit the vertical blasthole The hole depth is 1.8-2.2 meters, and all the holes are blasted once. 2 After blasting the first blasthole, stand on the ore heap and lay a second blasthole with a hole depth of 1.5-1.6 m. Then transport the first collapsed ore and set up artificial false alleys and wood. funnel.

2 Underground Gold Mining Method

This method is generally used for thin ore bodies or very thin ore bodies with a thickness of less than 4-5 meters and an inclination of the ore body greater than 60 degrees. When mining, the ore is mostly stratified horizontally. The rock drill is perpendicular to the blast hole at an angle of 45 degrees or nearly 90 degrees.

Optimized design of drilling and blasting operations in ...

1. Introduction. Mining activity is mostly represented by these four main operations: drilling, blasting, loading and hauling. For a proper mine planning and design, all of these operations need to be carefully planned in such a manner that can prevent extra loads such as operating costs, environmental footprints, etc. Amongst these operations, drilling and …

Long hole drilling applied to narrow reef mining - SAIMM

accuracy, there was no survey of the holes, and no blasting was done to expose hole barrels. A long hole mining system was then defined, with a corresponding face mining system, which led to the design of a test programme for the Solo drilling rig. Earlier experience at Telfer The proposed face mining system was based on a mining

Fatal Accidents Due To Flyrock And Lack Of Blast Area ...

produced silica flux for copper smelting. The ore was mined by drilling and blasting from shallow multiple benches. The mining company used a blasting contractor for loading and firing the shots. The blast round consisted of 49 holes, 3-in diameter, 12 …

Chapter 7 LOADING BOREHOLES - National Park …

When priming blasting agents with holes up to 2 1/2 inches in diameter, a full cartridge of high velocity explosives like 60 percent ammonia gelatin, gels, slurries, or cast primers with a blasting cap, is a sufficient charge. For larger holes, the priming requires much more care, especially if the hole is wet or decked charges are used.

Blast Hole Drilling: The Basic Process | RPM Drilling

Blast hole Drilling is a technique used in mining whereby a hole is drilled into the surface of the rock, packed with explosive material, and detonated. The aim of this technique is to induce cracks in the inner geology of the surrounding rock, in order to facilitate further drilling and associated mining activity.

What is the Mining Technology of Open Pit Mining?

Therefore, as for open pit mining, the process of trenching, stripping and mining is almost the same. 1. Blasting. Blasting work includes drilling holes and detonating. Common drilling equipment is rotary drill (Φ150-380mm), shallow-hole drill (Φ100-250mm) and jackhammer (<Φ100mm). Common explosives are ammonium nitrate fuel oil explosives ...

Blasting Principles - Orica

Mining to access the orebody (a term used in both surface and underground mining). Dilution. The undesirable lowering of ore grade by mixing waste material during blasting and mining. Dragline. A large excavation machine used mainly in surface coal mining to remove overburden (layers of waste rock and soil) covering a coal seam.

Optimization of Blasting Parameters in opencast Mines

Optimization of blast is dependent on a host of complex factors related to the rock, explosive, initiation, drill-hole parameters and their layout. The present work is a step in the direction of developing a suitable blast model, with simple methodologies which can be adapted by the mining industry to achieve better blasting results.

Mining Engineering Quiz | Mining Engineering Multiple ...

A Copper ore mining. B lron ore mining. C Coal mining. D Gypsum mining. View Answer ... More of less horizontally drilled holes at the foot of a high bench. ... exploitation or winning is: A The process of blasting. B The process of extracting the ore or economic mineral from the earth. C The process of ventilation. D The detailed mapping of ...

Long hole drilling for the platinum industry— a mining ...

• The steeper the dip, the more efficient is blast and gravity-assisted ore movement into secondary cleaning points (gullies) Figure 1. Typical in-stope long hole drilling layout for a trackless mining operation1 Blasting Cleaning with LHD Water jet …

Our open-pit mines - LKAB

Blasting. After drilling, the holes are charged with around 25 tonnes of explosive, which blasts out the rock. Loading. Loaders are used to load the ore into dump trucks, which transport the ore to an intermediate storage area and a crusher facility. The ore is then crushed and sorted, before being transported for further processing.

Underground Mining Methods - UFRGS

with thicker beds. Mining the ore body creates large open stopes where trackless machines can travel on the flat floor. Ore bodies with large vertical heights are mined in horizontal slices starting at the top and benching down in steps. Post room-and-pillar mining (Figure 1.3) applies to inclined ore bodies with dip angles from 200 to 550.

Unit 16 Mine Development - Mining and Blasting

opening a mine, a small mining company usually digs any ore that is showing. The revenue from the sale of the ore keeps the venture going and finances further development. After the ore body has been delineated and defined, a company may make several feasibility studies to determine the best way to mine the ore.

Grade Control & Blast Hole Drilling - Addison Drilling

While it is tempting to jump right into the mining process, grade control drilling should be done in order to find out exactly what type of minerals and ores it is that you are working with. Knowing the grade and variability of the ore being used is very important as it will assist you in deciding which types of drilling and mining are suited to the type of rock and mineral being mined.

PROCEDURES FOR BLASTING - New York State Department …

Blast Pattern – The plan view of the drill holes as laid out for blasting. Blast Plan – A written procedure that details the methods and manner by which a Project blaster will comply with pertinent laws, rules, regulations, and contract documents. The plan shall include all information, as detailed in Section 2A, necessary to evaluate the ...

Design methodology for underground ... - Mining and …

blasting refers to long hole blasting techniques as applied in mining methods such as bench stoping, sub level open stoping and SLC including undercut blasting and drawbell blasting in the case of block and panel caving methods. All of these methods have been fully described in Refs. 5 and 12. Ring design terminology