effect of stemming on the efficiency of explosives by Walter O. Snelling

Cover of: effect of stemming on the efficiency of explosives | Walter O. Snelling

Published by U.S. Govt. print. off. in Washington .

Written in English

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  • Explosives

Edition Notes

Book details

Statementby Walter O. Snelling and Clarence Hall. Rev. in 1928 by S.P. Howell and J.E. Tiffany ...
ContributionsHall, Clarence, jt. author., Howell, S. P. 1880-1937., Tiffany, Joseph Edgar, 1879-
LC ClassificationsTN1 .U6 no. 17b
The Physical Object
Pagination21 p. incl. illus., tables, diagrs.
Number of Pages21
ID Numbers
Open LibraryOL6721079M
LC Control Number28026250

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Thus the experiments showed conclusively that a given quantity of 40 per cent strength ammonia dynamite, with stemming, will do the same amount of work as a much larger quantity of the same explosive without stemming.

Book Details. Additional Physical Format: Online version: Snelling, Walter O. (Walter Otheman), b. Effect of stemming on the efficiency of explosives. Washington, Govt. Print. Buy The Effect of Stemming on the Efficiency of Explosives (Classic Reprint) by Snelling, Walter O.

at ISBN/UPC: Save an average of. The main purpose of this study is to investigate effect of blast design parameters such as burden, blast hole length, stemming length, and powder factor on rock fragmentation. The fragment sizes (MFS, K50, m), and maximum fragment size (K95, m) of rock were determined by using the computer by: 1.

Stemming does more than confine the explosive. It also protects the loaded explosives from acci-dental ignition or detonation. In the stemming operation, a small quantity of stemming should be care-fully and gently pressed over the charge.

The remainder of the stemming should be progressively added and firmly tamped into the hole. Bought this book in the 90's and glad I did because purchasing this book nowadays would prolly get you on some sort of watch list.

Granted the chemicals needed to make most of the stuff in the book are hard to get anymore but still a good read/5(5). effect of stemming on the efficiency of explosives book 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 costs under control. High-energy explosives enhance fragmentation, which ultimately produces a positive effect on production costs.

about to utilize the crushing effect of the explosive for maximizing blast efficiency and minimizing the cost (Miller, ). Theory of stemming plugs Stemming plugs were first developed in University of Missouri in in order to protect explosive gasses escaping from the blast hole.

The main. An explosive perfectly capable of producing an explosion may liberate its energy without producing one. Black powder, for example, may burn in the open air. An explosion may occur without an explosive, that is, without any material which con- tains intrinsically the energy needful to produce the explosion.

commercial explosives ranges from to g/cc. For free running explosives, the density is often specified as the pounds of explosives per foot of charge length in a given size borehole. With few exceptions, denser explosives give higher detonation velocities and pressures.

Density is an important consideration when choosing an explosive. A change in the configuration or type of initiation, priming or boosting can lead to a significant increase in blasting efficiency. The terms “primer” and “booster” are often confused. Primer is a unit of cap-sensitive explosive used to initiate other explosives or blasting agents.

The third edition of this popular book has been fully revised and updated and outlines the basic principles needed to understand the mechanism of explosions by chemical explosives. The history, theory and chemical types of explosives are introduced, providing the reader with information on the physical parameters of primary and secondary explosives.4/5(1).

Introduction. Hard rock engineering such as mining and tunnelling requires a huge amount of explosive energy. Unfortunately, the energy efficiency of rock blasting is very low (Langefors and Kihlström,Ouchterlony et al.,Sanchidrián et al.,Zhang, ).Therefore, it is important to increase the energy efficiency in rock : Zong-Xian Zhang, De-Feng Hou, Ziru Guo, Zhiwei He.

Proper Stemming increases the efficiency of the explosive allowing it to more easily break the burden and reduces the ground vibration from over-confinement; Stemming Materials.

The choice a mine makes for the material that is used for stemming is one of the most important considerations for blasting. The bureau has not been able to give much attention to explosives used in metal mines and quarries, but has published some information about these explosives in Bulle The Selection of Explosives Used in Engineering and Mining Operations; Technical Pa The Effect of Stemming on the Efficiency of Explosives; and Miners' Circular The Prevention of Accidents from Explosives Cited by: 1.

Stemming has been defined as the inert material used to backfill a borehole for the purpose of containing the explosive energy and reducing the unwanted effects of airblast and flyrock.

The two most discussed features of stemming are particle size and stemming column height. Stemming size has been traditionally selected in accordance with the holeFile Size: KB. EXPLOSIVES - ACETONE PEROXIDE (tricycloacetone peroxide) (original source - "kitchen improvised blasting caps") 1.

Go to the bank and take $20 out 2. Head to the nearest chemist/pharmacy, go up to the counter and ask for 6% peroxide, the File Size: KB.

In rock engineering, high temperature is a consideration with rock drilling, rock boring, rock blasting, extraction of geothermal energy and petroleum, and underground repositories of nuclear wastes.

This chapter discusses temperature effects on the physical properties, strengths, and fracture toughness of rocks. The environmental effects of underwater explosions with methods to mitigate impacts The effect of explosives on marine life.

California Fish and and J. Davis. The effects of stemming. Explosives & safety This latter effect of the expanding gases is termed heave. Velocity of Detonation • The velocity of detonation (VOD) is the rate at which the detonation wave travels along an explosive column.

The site geology and stability of the face. Access to the blast site for drill rig, delivery of stemming, explosives.

This paper describes the result of a systematic study on the impact of blast design parameters on rock fragmentation at three mines in India. The mines use draglines and shovel–dumper combination for removal of overburden. Despite its pivotal role in controlling the overall economics of a mining operation, Cited by:   Bench height is usually limited on the low end by the height of the stemming column required and its limiting effect on the amount of explosive that can be loaded, and limited on the high end by the height of the digging equipment (for safety reasons).

Sub-drilling = to times the burden. Intact rock properties, block size of rock mass before blasting and muck pile after blasting were found to measure blasting efficiency. Firstly, intact rock properties, which are unit volume weight, water absorption, uniaxial compressive strength, tensile (Brazilian) strength.

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(c) Record keeping in a designated stock book; (d) The issue and receipt of explosives; and (e) Immediately reporting any loss or theft of explosives to a suitable designated person.

Custody of explosives, etc. Explosives should remain under the control of suitable and authorised people, such as a shotfirer or trainee Size: 40KB.

stemming stemmer Stemming in blasting operations: (1) The process of filling the empty part of a charge case, such as a blasthole or well, with an inert stemming material (sand, gravel, or clay) to retain the products of the detonation of an explosive charge in an enclosed space.

Blastholes and wells are stemmed mechanically by pneumatic rammers and. Book-to-market effect or value effect. Stocks with high book-to-market ratios-- remember this is a book value of equity that you see in a balance sheet in the annual report of the firm divided by the market value of the equity.

Those type of firms we call them value firms historically have earned higher returns than growth firms, firms that. ingredients of the explosive Energy calculated by Thermodynamic Codes (ideal) (i.e. computer models of the detonation chemistry and energy of the reactions) Usually quoted in MJ/kg of explosive AWS of ANFO is cal/g for 94% AN and 6% Fuel Oil Explosive efficiency varies from 35% to 90% of maximum energy.

Search the world's most comprehensive index of full-text books. My library. Introduction to Explosives FOR OFFICIAL USE ONLY C4: Analysis and Trends U.S. manufactured so likely to be found in countries where the U.S.

has military connections A preferred terrorist explosive – Used in U.S.S. Cole and Bali nightclub bombings – Recommended in Al-Qaeda’s traditional curriculum of explosives training. Arabic Explosive Manual Translation 8 UNCLASSIFIED//FOR OFFICIAL USE ONLY Page 5 of Be careful when pressuring the detonators by teeth, by knife, or any other tools.

Third: Safety Rules in Transporting Detonators and Explosives 1. It is prohibited having explosives and detonators together during transportation or storage. Size: 1MB. Ecological impact of explosives are the effects that both unexploded explosives and post-explosion by-products have on the environment.

Explosive derived contaminants may have adverse effects on the environmental as well as human health. In addition to their military use in warfare, explosives are also used in construction and demolition.

Of greatest concern to the. Burden Calculations. Welcome to Academy Blasting’s video on burden calculations for bench blasting applications.

In this short 3 minute video by Anthony Konya, we will learn how to calculate burdens in both imperial and metric units. TYPES OF EXPLOSIVES & EXPLOSIVE EFFECTS 36 Dynamite. Flash Powder • Possibly the most dangerous explosives • A mixture of potassium perchlorate, aluminum and sulfur TYPES OF EXPLOSIVES & EXPLOSIVE EFFECTS Flash Powder TYPES OF EXPLOSIVES & EXPLOSIVE EFFECTS Photoflash Powder.

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HANDLING OF MISFIRES IN MINES: Dealing with it is potentially most dangerous activity. INTRODUCTION – Misfire means the complete or partial failure of a blasting charge to explode as explosive or pyrotechnical products that remain in the ground or in the muckpile might be triggered by any mechanical effect during the digging.

efficiency. If a quarry plans to use foot bench heights with 7 feet of sub-drill, a drill rig with foot-long steels may not be a good choice, because two steels will be required to complete one hole. Metal mines generally use foot bench heights, for. Trauma-informed care (TIC) involves a broad understanding of traumatic stress reactions and common responses to trauma.

Providers need to understand how trauma can affect treatment presentation, engagement, and the outcome of behavioral health services. This chapter examines common experiences survivors may encounter immediately following or long after a traumatic.

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Library of Congress Cataloging-in-Publication Data Agrawal, J. Organic chemistry of explosives / J. Agrawal and R. Hodgson. Includes bibliographical references and Size: 4MB.

the effect is an explosion. Classification of Explosives I. Propellants or low; explosives are combustible materials, containing within themselves all oxygen needful for their com-bustion, which burn but do not explode, and function by produc-ing gas which produces an explosion. Examples: black powder, smokeless powder.

A shaped charge is an explosive charge shaped to focus the effect of the explosive's energy. Various types are used to cut and form metal, initiate nuclear weapons, penetrate armor, and perforate wells in the oil and gas industry.

A typical modern shaped charge, with a metal liner on the charge cavity, can penetrate armor steel to a depth of seven or more times the diameter of .How to make Semtex Semtex is a powerful explosive that is widely used by terrorists.

It is a little more powerful that U.S C Here is the recipe to make it: Materials: 1. RDX High Explosive 2. PETN High Explosive 3. Motor oil, petroleum jelly, or vegetable oil 4. Mesuring device (cup, spoon, etc) 5. Wooden dowel or spoon for stirring 6.Sweden where Bulk Emulsion Explosives have been used.

A comparison is made with other types of explosives re­ garding costs for drilling and blasting. By using Bulk Emulsion Explosive it was possible to achieve a better breakage performance. In a copper mine this resulted in a decreased powder factor and thereby less cost for the Size: KB.

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