Blasting Terminologies PDF

BLASTING TERMINOLOGIES Airblast Blast - an airborne shock wave resulting - the detonation of explosives to from the detonation of explosive. break rock. Airdox Blast...

BLASTING TERMINOLOGIES Airblast Blast - an airborne shock wave resulting - the detonation of explosives to from the detonation of explosive. break rock. Airdox Blast area - a system that uses 10,000 lb/in2 - the area near a blast within the compressed air to break undercut influence of flying rock or coal. It will not ignite a gassy or concussion. dusty atmosphere. Blasthole Axial Priming - a hole drilled in rock or other - a system for priming blasting material for the placement of agents where a core of priming explosives. materials extends through most Blasting cap or all of the blasting agent charge depth. - a detonator initiated by safety fuse. Ammonium Nitrate (AN) - most commonly used oxidizer in explosive and blasting agents. Blasting circuit ANFO (Ammonium Nitrate / Fuel Oil) - the circuit used to fire one or more blasting caps. - an explosive material consisting of a mixture of ammonium nitrate Blasting crew and fuel oil. It is commonly used blasting agent. - a crew whose job is to load explosive charge. Back Break Blasting machine - rock broken beyond the limits of the last row of holes. - any machine built expressly for the purpose of energizing blasting Back holes caps or other types of initiators. - the top holes in tunnel/drift Blockholing round. - a method of breaking a boulder Base charge with explosives placed in a small borehole. - the main explosive charge in a detonator. Blockhole Capped primer - a hole drilled into a boulder to - a cartridge of cap-sensitive allow the placement of a small explosive specifically designed charge to break a boulder. to transmit detonation to other explosives & which contains a Booster detonator. - a unit of explosive or blasting Cartridge agent used for perpetuating or intensifying an explosive - a rigid or semi-rigid container reaction. of explosive or blasting agent of a specified length or diameter. Bootleg Cast primer - portion of a borehole that remains relatively intact after - a cast unit of explosive, usually having been charged with pentolite or composition B, explosive and fired. It may commonly used to nitiate contain unfired explosive & detonation in a blasting agent. hazardous. Chambering Brisance - the process of enlarging a - a property of explosive roughly portion of blasthole (usually the equivalent to detonation bottom) by firing a series of velocity. An explosive with a small explosive charge. high detonation velocity has Collar distance high brisance. - the distance from the top of the Bulk strength powder column to the collar of - strength of explosive per unit the blasthole, usually filled with volume. stemming. Burden Column charge - the distance to the nearest free - a long, continuous charge of or open face from an explosive explosive or blasting agent in a charge. borehole. Capped fuse Control blasting - length of safety fuse w/ an - techniques used to control attached blasting cap overbreak & produce competent final excavation wall. Coyote blasting Decoupling - the practice of driving tunnels - the use of cartridged products horizontally into a rock face at significantly smaller in the foot of the shot. Explosives diameter than the borehole. are loaded into these tunnels Decoupled charges are and used where it is impractical normally not used except in to drill vertically. cushion blasting, smooth blasting, pre-splitting, and other Cushion blasting situations where crushing is - a blasting technique used to undesirable. produce competent slopes Deflagration where holes, are fired after the main charge, have a reduced - a subsonic but extremely rapid spacing and employ decouple explosive reaction accompanied charges. by gas formation and borehole pressure but w/o shock. Cut Delay blasting - an arrangement of holes used in U/G mining and tunnel blasting - the use of delay detonators or providing a free face for the connectors that cause separate remainder of the round to break. charges to detonate at different times rather than Cutoffs simultaneously. - a portion of a column of Delay connector explosives that has failed to detonate owing to bridging or a - a non-electric, short-interval shifting of the rock formation, delay device for use in delaying often due to an improper delay blasts that are initiated by system. detonating cord. Deck Delay detonator - small charge/portion of a hole - an electric or non-electric loaded with explosives & detonator with a built-in separated from other charges by element that creates a delay stemming or an air cushion. between the input of energy and the explosion of the detonator. Density - the weight per unit volume of explosive expressed as cartridge count or g/cm3. Detonating cord a height into large boulders to break them into smaller - a plastic covered core of high- fragments. velocity explosive, usually PETN, used to detonate Dynamite explosives. The plastic - the high explosive invented by covering is covered with Alfred Nobel. Any high various combinations of textiles explosive where the sensitizer is and waterproofing. nitroglycerin or a similar Detonation explosive oil. - a supersonic explosive reaction Electric storm where a shock wave propagates - an atmospheric disturbance of through the explosive intense electrical activity accompanied by chemical presenting a hazard in all reaction that furnishes energy to blasting activities. sustain stable shock wave propagation. Emulsion Detonation pressure - an explosive material containing substantial amounts - the head-on pressure created by of oxidizers dissolved in water the detonation proceeding down droplets surrounded by an the explosive column. immiscible fuel. Detonator Explosion - a device containing a - a thermochemical process detonating charge that is used to where mixtures of gases, solids initiate an explosive. It includes or liquids react with the almost blasting caps, electric blasting instantaneous formation of gas caps and non-electric pressure and sudden heat instantaneous or delay blasting release. caps. Explosive Downline - any chemical mixture that - the line of detonating cord in reacts at high velocity to the borehole that transmit liberate gas and heat causing a energy from the trunkline down very high pressure. It is a solid the hole to the primer. or liquid substance or mixture Drop ball of substances which, on the application of a suitable - also known as “headache ball”. stimulus to a small portion of An iron or steel weight held on the mass, is converted in a very a wire rope that is dropped from short interval of time into other  more stable substances, largely Fracturing or entirely gaseous, with the - the breaking of rock with or development of heat and high without movement of the pressure. broken pieces. Explosive material Fragmentation - this includes dynamite and - the extent that a rock is broken other high explosives, slurries, into pieces by blasting. water gels, emulsions, blasting agents, black powder, pellet Gelatin powder, initiating explosives, detonators, safety fuses, squibs, - an explosive or blasting agent detonating cord, igniter cord, that has a gelatinous and igniter. consistency. Extra dynamite Gelatin dynamite - also called “ammonia dynamite - a highly water-resistant that derives the major portion of dynamite with a gelatinous its energy from ammonium consistency. Gun powder, nitrate. blasting powder (BP) – a low explosive consisting of Face potassium or sodium nitrate, charcoal, and sulfur. It has low - a rock surface exposed to air. energy, poor fume quality, and Also called as “free face” which extreme sensitivity to sparks. provides the rock with room to expand upon fragmentation. Hangfire Firing line - the detonation of an explosive charge after the designed firing - a line, often permanent, time. extending from the firing location to the electric blasting Hertz cap circuit. Also called as “lead wire”. - a term used to express the frequency of ground vibrations Fly rock and airblast. One hertz is one cycle per second - rock that is propelled through the air from a blast. Excessive Highwall fly rock may be caused by poor blast design or unexpected weak - the bench or ledge on edge of a zones in the rock. surface excavation. Ignitacord of the excavation and the holes are not loaded with explosive. - a cordlike fuse that burns progressively along its length Low explosive with an external flame at the - an explosive where the speed of zone of burning and is used for reaction is slower than the speed lighting a series of safety fuses of sound, such as black powder. in sequence. Magazine - a building, structure or Initiation container specially constructed - the act of detonating a high for storing explosives, blasting explosive by means of a cap, agents, detonators, or other mechanical device, or other explosive materials. means. Mat Jet Loader - a covering placed over a shot to - a system of loading ANFO into hold down flying material small blastholes where the usually made of woven wire ANFO is sucked from a cable, rope or scrap tires. container and blown into the Misfire hole at high velocity through a loading hose. - a charge that has failed to fire as planned and still contain Kerf explosives. - a slot cut in a coal or soft rock Muck pile face by a mechanical cutter to provide a free face for blasting. - a pile of broken rock or dirt that is to be loaded for removal. Lead wire - the wire connecting the electrical power source with the Mud cap leg wires or connecting wires of a blasting circuit. - a charge of explosive fired in contact with surface of a rock Lifter usually covered with a quantity of mud, wet earth or similar - the bottom holes in a tunnel or substance with no borehole is drift round. drilled. Line Drilling - an overbreak control method where a series of closely spaced holes are drilled at the perimeter Nitroglycerin (NG) Pattern - the explosive oil originally - a drillhole plan laid out on a used as the sensitizer in face or bench to be drilled for dynamites, C3H5(ONO2)3 blasting. Nitromethane Pellet powder - a liquid compound used as a - black powder pressed into 2- fuel in two-component (binary) inch long, 1 ¼ - to 2-inch explosives and as rocket and diameter cylindrical pellets. dragster fuel. Pentaerythritoltetranitrate (PETN) Nitropropane - a military explosive compound - a liquid fuel that can be used as the core load of combined with pulverized detonating cord and base charge ammonium nitrate prills to of blasting caps. make a dense blasting mixture. Pentolite Nitrostarch - a mixture of PETN and TNT - a solid explosive similar to used as a cast primer. nitroglycerin used as the base of Permissible explosives “nonheadache” powders. - those explosives that been Overbreak approved by MGB for use in - excessive breakage of rock U/G coal mines. beyond the desired excavation Pneumatic Loader limit. - one of a variety of machine Overdrive powered by compressed air - inducing a velocity higher than used to load bulk blasting the steady state velocity in a agents or cartridged water gels. powder column by the use of a Powder chest power primer. It is a temporary phenomenon, and the powder - a strong, nonconductive quickly assumes its steady state portable container equipped velocity. with a lid used at blasting sites for temporary explosive Oxidizer storage. - an ingredient in a explosive or Powder factor blasting agent that supplies oxygen to combine with the fuel - a ratio between the amount of to form gaseous or solid powder loaded and the amount detonation products. of rock broken. Preblast survey Propagation blasting - a survey used to determine - the use of closely spaced, whether subsequent blasting sensitive charges. The shock causes damage to the structures. from the first charge propagates through the ground, setting off Premature the adjacent charge and so on. - charge that detonates before Propellant explosive intended. - an explosive that normally Presplitting deflagrates and is used for - controlled blasting where propulsion. decoupled charges are fired in Primer closely spaced holes at the perimeter of excavation & holes - a cartridge of HE incorporating are fired before the main blast. a detonating device. This is the key element of a charge of Prill explosive. - a small porous sphere of Pull ammonium nitrate capable of absorbing more than 6% by - the quantity of rock or length of weight of fuel oil. advance excavated by a blast round. Primary blast Relievers - the main blast executed to sustain. - holes adjacent to the cut holes used to expand the opening Primary explosive made by the cut holes. - an explosive mixture sensitive Rib holes to spark, flame, impact, or friction used in a detonator to - the holes at the sides of a tunnel initiate the explosion. or drift round that determine the width of the opening. Primer Round - a cartridge of cap-sensitive explosive used to initiate other - a group or set of blast holes explosives or blasting agents used to produce a unit of and that contains a detonator. advance in U/G headings. Propagation Safety fuse - the detonation of explosive - a core of potassium nitrate charges by an impulse from a black powder, enclosed in a nearby explosive charge. covering of textile and  waterproofing, used to initiate a Spacing blasting cap or black powder - the distance between holes or charge. charges in a row measured Sensitizer perpendicular to the burden distance. - an ingredient used in explosive compounds to promote greater Squib ease in initiation or propagation - a firing device that burns with a of the detonation reaction. flash. Shock wave Staggered pattern - a pressure pulse that propagates - a blasthole pattern where the at supersonic velocity. holes in each row are drilled Shunt between the holes in the preceding row. - a piece of metal or metal foil that short circuits the ends of Stemming cap leg wires to prevent stray - the inert material such as drill currents from causing cuttings, used in the collar accidental detonation of the cap. portion of a blasthole to confine Slurry (water gel) the gaseous products of detonation. - an aqueous solution of ammonium nitrate sensitized String loading with a fuel, thickened, and - loading cartridges end-to-end crosslinked to provide a in a borehole w/o deforming gelatinous consistency. them and used mainly in Smooth blasting controlled and permissible blasting. - controlled blasting where a series of closely spaced holes Subdrill are drilled at the perimeter, - the extended hole depth of loaded with decoupled charges blasthole beyond the planned and fired on the highest delay grade lines or below floor level period of the blast round. to ensure breakage to the Snake hole planned grade or floor level. - a hole drilled slightly Swell factor downward from horizontal into - the ration of the volume of the floor of the quarry. materials in an undisturbed state to that when broken. Subsonic Toe - slower than the speed of sound. - the burden or distance between the bottom of a hole and the Supersonic vertical free face of a bench in - faster than the speed of sound. an excavation. Slurry Trinitrotoluene (TNT) - an aqueous solution of AN - a military explosive compound sensitized with a combustible used industrially as a sensitizer fuel (and thickened with gelling for slurries and as ingredients in agent at the point of charging). pentolite and composition B. Tamping Trunkline - compressing the stemming or - a detonating cord line used to explosive in a blasthole. connect the downlines of other detonating cord lines in a blast pattern and usually runs along each row of blast holes.