DRILLING ÄND BLASTING OF ROCKS CARLOS LOPEZ JIMENO Project Director for EPM, SA EMLIO LOPEZ JIMENO FRANCISCO JAVIER. Submitted By. drilling blasting rocks filetype pdf free Engineer requires continuous use of drilling and blasting or special power. Facts About: Underwater Drilling. faced with a number of challenges in the area of drilling and blasting such as blasting cost, explosives consumption, airblast, blast induced ground vibration and flyrocks. Sorry, there is no online preview for this file type.
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Drilling and Blasting of Rocks
From this relationship it can be deduced that the penetration rate for a given rock and for a determined drilling diameter is linearly proportional to the thrust and rotary speed, although this is not completely true in practice, as it has been indicated that the friction coefficient of the rock varies with the Uinist.
The larger rock, within those distribution curves, is called rip-rap. Room and pillar mining. In the following paragraphs some simple rules are given for an initial approach to the geometric design of blasting and the calculation of the charges, characterizing the rocks exclusively by their uniaxial compressive strength.
Drilling and Blasting of Rocks – [PDF Document]
The hamrners can be driven hydraulically or pneumatically. Underground prc duction blastingthe hole opened, improved selectivity and ore recovery.
Underground charging of slurried und emulsions Loading blastholes in underground operations has different methods, depending upon the type of work at hand: Konon Nitro Consult, A. Degree of confinement Highly confined Reasonably free 2. The mineral strength depends upon the size of the crystals and diminishes with their increase.
At first glance it looks complex, 8. The number and length of these radial cracks increase with: The wave travels at high speed and its shape depends basically on the design of the piston.
For these reasons, the horizontal and vertical dnlling should beheight, because they permit the use of a glory hole raise for the evacuation of the broken rock. Paddock T Peal, S. Depending upon the pump speed, a 3 meter long filteype with 41 rnm in diameter can be charged in 6 to 10 seconds. This is achieved by firing a row of blastholes on the side opposite the fall, with a delay blastig of 0.
Drilling and blasting
Hansson Nitro Nobel AB: As for Span bridges, constructed with pretensed concrete beams, demolition is carried out in two different phases: As can be observed, when the velocity increases, a larger quantity of energy is required to obtain satisfactory fragmentation.
Apart from the equipment already described, there rcoks lighter models on the market which can be transported by the Operator himself, with a capacity of from 25 to 40 kg of ANFO. For this reason, the authors of this manual feel that in a near future, all the blasring equations are going to Q used as guidelines for designing e tentative blastings and that afterwards, once the characteristics of the rocks have been determined through rrocks the blasthole drilling, the optimum Patterns or the explosive charges in each blasthole for an established pattern, will be determined.
Charging equipment for development headings. Piston at the end of its return stroke.
This resisting torque is determined by the rninimum torque of the rock rokcs that allows the rock to be penetrated. The velocity of air flow for efficient cleaning with air goes from 15 to 30 mls. If the structure is complex and is next to other buildings that have to be respected, a careful study must be canied The two most common types of demolitions are: The loading hose is located in the back of the truck and is about 10 m in length which permits the charging of 3 or 4 blastholes from the Same position when the truck is driven between two rows.
With this movement, the bit is turned so that the impacts are produced on the rock in different positions. If the ground is good, a systematic bolting of the surface with gunite reinforcement steel ribs is usually performed flietype, if the rock is poor, the excavation is carried out in transversal sections, leaving between them others that are not excavated until the arches aiready opened have been concreted.
Blast-hole drilling at the Bingham Canyon MineUtah. The variation in blasting costs with increase in blasthole diameter differs from those of drilling, because part of the advantages are baianced out by some problems cited below: The elastic properties of rocks are charactenzed by vlasting elasticity module ‘E’ and the Poisson coefficient ‘ V ‘.
The front surface area is much larger than the back 10 so the piston moves towards the rear. Although hand held drills and pushers can be used for the drilling with blastholes of 29 to 33 mm diameters, the normal practice is to use drilling Wagons and jumbos with larger blastinng such as 33 to 64 mm.