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By Terry Graf, Bill Thompson, John Guenther

SYNCRUDE CANADA LTD.. operates the largest synthetic crude oil production facility in the world. Over 60,000,000 Bank Cubic Metres of oil sand is mined each year from their open pit located in Fort McMurray, Alberta. Despite the extremely cold temperatures encountered during the winter months and the problems associated with frost buildup, SYNCRUDE has continued to operate on a 12 month per year basis. In 1989 SYNCRUDE mine management embarked on a comprehensive Frost Blasting program to improve mine production of their oil sand moving equipment. The following paper will discuss the development of their frost blasting program to its current status.

Jan 1, 1993

By Vaughn Bowns, Allen Stanley, Brian Redeker

"Running casing in drilling operations is often complicated by boulders or large cobbles.Past practices of dealing with these have included use of drop hammers, attempts to drillthrough or around the boulder, contact explosive charges and even pulling the casing andrepositioning the hole. All these methods are time consuming, expensive and offer noguarantee of success. In this paper a different method of dealing with these boulders ispresented that promises to be faster and less expensive with a much higher success rate.This involves using a light plastic conduit pipe to place a shaped explosive against theboulder. It requires no special tools or techniques not commonly in use in the drilling andblasting industry."

Jan 1, 1993

By Michael S. Wieland

This report discusses the U.S. Bureau of Mines research regarding the desensitization and malfunction of cap-sensitive explosives deployed in underground coal mines. Delay blasting in underground coal generates severe shock waves and rifting forces that fracture and heave coal. These dynamic interactions can damage other charges still remaining in the delay pattern. The debilitating impacts precipitate degrees of reduced charge performance ranging from misfires to weak detonations or out-of-sequence firings. Damaged charges react poorly, perform less useful work, and/or generate atypical fumes with higher toxicity.

Jan 1, 1993

By S Lukovic, Vishwa Bhushan, Calvin J. Konya

Effect of each of these variables has been well characterized for ANFO. This paper presents results of underwater energy measurements for one watergel and one emulsion type of slurry explosive which were initiated by 3 types of initiators (one electric and two cords of different strength) in 2 and 3 inch diameter steel pipes. Results of this 2 x 3 x 2 factorial experiment show the effects of detonating cord on energy released by the watergel and the emulsion explosive. Effect of diameter and its interaction with cord strength have also been characterized for the two explosives.

Jan 1, 1986

By Richard Arsenault

The production of oil & gas from wells requires method of flow from the producing formation into the well bore. Once the well is drilled it will have casing pipe installed to protect the integrity of the well formations and means of delivery to the surface. Once casing pipe is installed it will be cemented in by pumping cement through the annulus of the casing pipe down to the bottom of the well and allowed to flow outside the casing pipe up into the formation.

Jan 1, 2007

By C A. "Hawk" Hanger

"The paper that will be presented is an in-depth study of sequential blasting using standardnon-electric shock tube down hole timing along with surface M.S. connector timing.Included also will be a discussion on the advantages in fragmentation, digability, oredilution' and ground vibration versus the common practice of row by row blasting. Alongwith the written presentation, several visual illustrations will be included. The visuals willrefine the actual direction and predicted movement of the shot involved."

Jan 1, 1993

By Mike Koehler

An underground mine that produces aggregate limestone was in operation for approximately eight years when geological changes resulted in dangerous rock falls. The roof in the mine was not bolted; therefore, the drilling and blasting program was called upon to maintain roof integrity. Drilling and blasting were analyzed and modifications were adopted to stabilize the roof. Initial changes were made in the drilling equipment, drill pattern, explosive type, and timing. Any amendments made, after the initial phase, were made individually so it would be easy to discern which changes worked.

Jan 1, 2002

By Mark S. Stagg, Stephen A. Rholl, Steven G. Grannes

A method of determining the fragment size distribution of rock quarry muckpiles using photographic and digital-image processing techniques has been developed by the Bureau of Mines. To assess the fragmentation, photographs and video tapes were taken in both the laboratory and in the field and then digitized for analysis. The fully-automated process uses specially written image-interpretation software which had been developed previously by Bureau researchers to measure irregular taconite ore shapes. The advantages of photographic assessment in comparison with other methods include speed and cost.

Jan 1, 1993

By Edward J. Walter

An ancillary effect to every blasting operation is the generation of vibration Extensive research has been performed for the purpose of understanding, controlling, and predicting this vibration An examination of these studies clearly shows a variability in the resulting vibration effects It seems logical to expect that identical blasting procedures should produce identical vibration levels, but this is rarely the case. There is a distinct pattern of variation.

Jan 1, 1980

By S C. Alford

Explosive fracturing of metal is usually considered to be an imprecise process but, by careful consideration of shock-wave geometry, precise results are obtainable. The limited development of such charges is attributed to experimental difficulties. A charge configuration has now been devised in which a prismatic wave-shaping element is used to resolve the shock-waves entering a target plate into two convergent components. The extreme pressure caused by their collision initiates a diamond fracture in the proximal target face, and coincidence of reflected tension waves generates a fracture in the distal face. A combination of these effects breaks the target. An embodiment of S.R.T. is described which is flexible, magnetic and contains no cavities.

Jan 1, 1986

By Rodger Andrews

High cost - low productivity mining methods at the Homestake Mine forced the need for a new and safer means of ore extraction. Vertical Crater Retreat (VCR) was introduced in 1978 and accounts for over 50% of the underground mine production today. Many advantages can be attributed to this form of "bulk mining"; including steady production, decreased labor costs, and the ability to mine bulk stopes in the lower portion of the mine. However, safety and high productivity are the two major advantages. This paper will deal specifically with crater blasting and the application of mass blasting techniques in Vertical Crater Retreat slopes.

Jan 1, 1988

By Omer Yilmaz Erkoc, Gulsec Uyar Aldas

Blasting techniques, which have been used for a long time in Turkey, are powerful and economical tool in producing raw material in mining, quarrying, construction .etc. industries. The development of the society within the world has resulted in a substantial increase in the scale of such industrial projects. However, the expansion of such activity has been matched by an increased public awareness of environmental issues, particularly when it occurs in relatively close proximity to residential areas. One of the most troublesome issues facing the mining, quarrying and construction industries when carrying out their blasting activities is that of ground vibration. Because, blasting induced ground vibration can reach to very far distances from the source and has the potential for damage to concern to the inhabitants of property.

Jan 1, 2002

By Petr Mostak, Miroslav Horacek, Miroslav Stancl

Detection of plastic explosives is an important task in the security measures against criminal misuses of this type of explosive. Particles and vapour detectors are basic instruments in this detection. Colour reactions and dogs are also used. Marking system in accordance with requirements of Montreal Convention was developed and applied in full scale production of plastic explosives including Semtex since 199 1. The influence of marking on technology, performance and other properties of plastic explosives is discussed. 2,3 dimethyl 2,3 dinitrobutan is the most popular marking agent which is broadly used. The detectability of this compound is not optimum by some detectors. The substantial effort has been given to development of plastic explosives with controlled shelflife. Some results of this work are presented. Technical and economic aspects of identification marking are discussed.

Jan 1, 2001

By George P. Jr Schivley

Data is presented showing Penetration Rate (PR) versus Force-on-the Bit (FB) and Bit Angular Speed (N). Using this data, it is shown how FB and N each uniquely contribute to the PR for any particular drilling situation. This data represents many mining situations; including coal, copper, gold, iron ore and limestone quarrying. The important relationship between Penetration per Revolution (P/R) and the height of the cutting elements of the bit (CH) is discussed. Drill performance is then reviewed, considering the effect of FB and N on bit life. All this leads to recommendations for the operating values of FB and N for drilling situations where the rock is not highly abrasive and bit replacements are because of catastrophic failure of the bit cone bearings.

Jan 1, 1995

By D Linn Coursen

Detonation propagates in the subject blasting agent at about 2.7 km/sec when it is heavily primed but explosion propagates in it at only about 0.43 km/sec when it is lightly primed. When propagating at 0.43 km/sec, it produces a borehole pressure that is slightly less than 1 kb, but no yellow fumes or other sign of incomplete reaction. It is a pumped AN/emulsion blend to which additional water is added by circumferential injection at the inlet of the hose through which it is pumped.

Jan 1, 1994

This case history refers to the detonation of the two largest chemical explosions on the Australian continent. An important element of feasibility studies and construction guidance included prediction of fragmentation results and ground vibration effects for the detonation of two very large "coyote" blasts, consisting of mined tunnels filled with explosives. The larger of the two blasts contained nearly 1 1/4 million pounds of explosives detonated instantaneously. The explosives were placed in specially designed tunnels under a quartzite mountain for the purpose of generating rock fill for the main dam on the project.

Jan 1, 1995

By Wesley L. Bender, James E. Murray

Pre-blast surveys are often conducted solely to document existing structural conditions and uncover potential problem areas. This paper presents a case history where the pre-blast survey was also used as a vehicle to initiate a public relations program with the occupants of a large apartment complex adjacent to a major excavation site. The public relations program, in conjunction with good blasting practices, succeeded in keeping complaints to a minimum. The presentation includes an overview of the project, details of the public relations program, some of the blasting methods that were utilized and a recap of the complaints received.

Jan 1, 1988

By Erik Nygaard, Klaus Voges

ANFO is the most used industrial blasting agent in the world, and is often used as a reference for comparison of other explosives. It is known to work very well under dry conditions in large borehole diameters, whilst in small borehole diameters increasing amounts of toxic fumes (CO, NO and NOz) can be formed. In underground blasting, problems can also occur with reduced visibility caused by unreacted ammonium nitrate and overall composition of the detonation fumes. ANFO is made by mixing Ammonium Nitrate Porous Prills (AN-PP) and fuel oil. We have measured velocity of detonation (VOD), toxic fumes and visibility after blasting of ANFO in 54x2 mm steel tubes, and the differences are remarkable: By using an AN-PP grade developed for underground blasting and small diameters, the following can be obtained:

Jan 1, 2001

By Lyall Workman, P D. Katsabanis

Energy released by the explosive is typically partitioned in brisance, heave and losses. The fact that energy released in the P-V expansion curve below a certain point is lost has resulted in the concept of available energy. Through simple calculations it is shown that energy released at pressure levels thought to be low, amounts to a significant proportion of the total energy value. Furthermore, throw calculations indicate that the assumed loss of that part of energy does not justify practical results. Loss of energy at the low pressure levels may also not be justified from the fragmentation point of view as pressure levels below 1 kbar are enough to extend radial fractures around a borehole. Finally the equation used for the P-V behaviour of the explosive gases is important in throw calculations. Simplified approaches may not reproduce the performance of the explosive which is not characterized only by its energy content.

Jan 1, 1998

By S. J. Dillingham

One of the primary goals of every blaster is to achieve the optimum blast design. Too much focus on efficient design, however, can cloud certain issues and exposures that must be addressed if the entire project is to be considered .successful.. Due to the known human response to blast effects and inherent dangers present in the use of explosives, the potential for the project being delayed or shutdown, or the blaster and associated company being named as a defendant in a lawsuit, is always a possibility. Therefore, the blast design and associated project bid must incorporate sound safety contingences and procedures that address those .what-if. Scenarios that may arise as a result of vibration, flyrock, public relations, and job-site personal safety.

Jan 1, 2002