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By Kamal Wadhwa

Liquid oxygen explosives have been used in India for well over 5 decades now. These are being extensively used both for shallow and deep hole blasting in the various opencast mines and quarries for mining of coal, limestone, ironore, bauxite, magnesite etc. IOL Ltd., are the pioneers in the introduction of these explosives in India and are marketing these under the brand name 'LOXITE'.

Jan 1, 1991

By Curtis Garner

Griesemer Stone located in Springfield, Missouri has supplied aggregate in Southwest Missouri since 1946. In 1954 the decision was made to mine the formation and utilize the mined out area for warehouse space. As advancement proceeded, entrances and small diameter air shafts for ventilation were needed and had to be added. It was decided in 1989 to sink an 8' diameter air shaft designed to move 200,000 cubic feet of air per minute with the help of (4) four 50,000 CFM Loren Cook Fans.

Jan 1, 1991

By John R. Coulson

A survey of federal and state licensing requirements for blasters employed on the surface and underground was conducted for the Bureau of Mines. Subdivisions include surface and underground (large and small), metal, nonmetal and coal. The requirements for certification, class of license, available training, types of testing and enforcement practices are discussed. Included are recommendations of some of the industry trade organizations.

Jan 1, 1980

By Norman Kramer, Roger Keller

The authors would like to thank Austin Powder Company for their technical support and input, specifically Stephen Harris, Jason Ryan, and John Capers of Austin Powder, without whose support this paper would not have been possible. Thanks are also extended to Nick Francis of Sandia National Laboratories and Jim Houseworth of Duke Engineering for their input regarding Performance Assessment.

Jan 1, 2000

By William B. Lee, James J. Jurmu

The Cleveland-Cliffs Iron Company operates three open pit iron mines on the Marquette Iron Range of Michigan's Upper Peninsula. Open pit iron ore mining began in the area in the 1840's. Underground mining was predominant from 1860 through 1960. Large scale low grade-open pit iron ore mining began in the early 1950's with the establishment of the Humboldt Mine, concentrator and pelletizing plant. This pit operated until 1970, when the reserves were exhausted.

Jan 1, 1986

By E Emery Jr Gray

A need for more delay periods other than those normally manufactured throughout the explosives industry rarely occurs. This paper will discuss one such incident from an analytical view through practical application.

Jan 1, 1976

By Philip Barnhard, Lyman G. Bahr

By recording the arrival time of a pipe wall at evenly spaced intervals in a plane perpendicular to the pipe axis, application of the equations of motion permits calculation of the pressure of the explosive acting to accelerate the pipe wall. Data observed from various non-ideal explosives are presented, together with values of pressure to be expected from thermodynamic calculations.

Jan 1, 1981

By Alfred Osborne

Progressive cavity type pumps are widely used by commercial explosive manufacturers for pumping water gel, emulsion and emulsion / ANFO blend explosives. Tests by explosives companies and investigations into incidents have shown that this type of pump can develop dangerously high temperatures when operated deadheaded or dry. [i.e. with no flow of product through the pump.] In some tests and incidents, explosion or detonation of the explosive (or residual explosive) in the pump has resulted.

Jan 1, 2002

By Neil E. Gehrig

The word "slurry" was used by Dr. Melvin Cook and Mr. Henry Farnam to describe a new blasting agent developed in 1956. This development, along with the development of ANFO triggered the Modern Era of Blasting. We have seen the results, a massive expansion in the commercial explosives industry. Someone once said, "You can't know where you're going if you don't know where you've been." With that in mind, this paper deals to some extent with the origin and development of slurry explosives and then with their future high potential.

Jan 1, 1982

By Raymond M. Dixon, Dale L. Ramsey

Upon being introduced to the MAGNETIC COUPLING concept,Balsinger,Inc. wanted to conduct field trials to explore the potential of Magnetic Coupling in the U.S.. Although the Magnetic Coupling Concept has been widely used, the U.S. proposed blasting criterion not previously addressed by the system. Modification to the system assembly and blasting accessories had to be made to make the system adaptable to our specific requirements. The field trials and system modifications are the basis of this paper.

Jan 1, 1990

By Dale S. Preece, J Paul Tidman, Stephen H. Chung

A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been under development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in 2-D. DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993).

Jan 1, 1997

By John A. Huber

At an underground limestone mine in the Central United States; there were plans for the installation of a limestone processing plant. The special design and layout of the plant called for the installation of a tunnel from the underground mine to the surface above. The dimensions of the tunnel would be 10 feet high, 20 feet wide, and would be 500 feet long on a 17 degree incline. The tunnel would be used for the transportation of raw stone to the surface by a conveyor. A second conveyor would transport processed limestone into the mine for storage, that would be loaded out for shipment later.

Jan 1, 1995

By Oldrich Machacek

Seismic explosives are very important tools in the search for oil and gas. Changes and new techniques in seismic exploration methods are also demanding new developments in seismic explosives. This article concentrates on three problems, characteristics of surface seismic explosives,causes of fires in application of surface seismic explosives and new developments in downhole seismic explosives.

Jan 1, 1985

By D. K. Ingram, G. L. Mowrey, T. R. Rehak

This paper summarizes flyrock and blast area security fatalities from 1989 to 1999 and examines the causative factors. Coal and nonmetal mining used about 43 billion pounds of explosives and blasting agents between1989 to 1999. A majority of this consumption was used at surface mines. Accident data indicates that flyrock and lack of blast area security were the primary causes of blasting related injuries in surface mining. Fatal injuries due to lack of blast area security were attributed to: failure to clear blast area; failure to follow instructions; inadequate guarding; inadequate blasting shelter; and unsafe location.

Jan 1, 2002

By Tom McDonald, Rodney Burke

As mining progresses in the West, the depth of material has increased, making highwall stability a major factor in safety and production. The Jim Bridger Coal Mine has made highwall stability a priority, concentrating on safety as well as increasing and improving production. Overburden depths are increasing dramatically; the geological environment consists of medium to soft material, faulting, water, and current pit alignment not favorable to joint planes. Angle drilling the presplit at 20 degrees became necessary as vertical presplit drilling produced wall failures.

Jan 1, 1997

By John Watson

Overview: Intro and Product Use Trends ?? Packaged Explosives ?? Bulk Explosives ?? Initiation Systems – Conventional Initiation Systems – Electronic Detonators ??Q&A

Jan 1, 2006

By Ken Fiorentino, Gordon F. Revey

H3 Tunnelers recently excavated two conventional 48 foot diameter highway tunnels through the Halawa side of the Tran-Koolau Mountains on Oahu. The primary blast design challenge on this Job was minimizing overbreak In the alternating layers of pahoehoe and aa lava, clinker, end tuff. Two different excavation techniques were evaluated in the Halawa tunnels. The first method used drilling and blasting to excavate the tunnels to within one foot of their final perimeter. A roadheader, mounted on a backhoe, was then used to excavate the remaining foot of ground. The second method used conventional smoothwall blasting techniques, without any mechanical excavation. This paper describes the details and relative success of the two excavation methods tried in the Halawa tunnels.

Jan 1, 1993

By Calvin J. Konya

There have been many different brands of high precision caps introduced on the US market in the last five years. High precision timing definitely effects the performance of the blast. One should be able to optimize fragmentation and minimize environmental effects with the use of high precision caps and selection of the proper time period. The consumer who purchases the caps may not be fully aware of the tolerances in firing times of caps used in the field. This paper will discuss results of field tests of cap tolerances from an independent study conducted by Precision Blasting Services.

Jan 1, 1989

By Joseph W. Hejny, Marlyn G. King

Coal mining in the Powder River Basin has changed in recent years to accommodate the large quantity of coal produced. With strip ratios of one to one and up to three to one, extensive amounts of overburden have to be removed to get to the large thick seams of coal. Larger shovels and trucks have been implemented in the removal of this overburden. The addition of draglines and continuous miners have been added to increase the production of coal. Drills used today are capable of drilling up to 13.5 inch blast holes.

Jan 1, 1994

By D. Bartley, R. McClure, W. Reisz

Ever since the 8ms criterion was developed in the early 60’s there has been an ongoing debate among many blasters as to its actual value in controlling ground vibration. The perpetuation of the myth surrounding the 8ms window can be partly attributed to its simplicity and convenience as a means for regulatory compliance. Unfortunately, the mindset that many blasters have adopted has hindered the development and use of more effective techniques and in many cases can actually be counter productive to vibration control.

Jan 1, 2006