|Statement||by Walter O. Snelling and Clarence Hall.|
|Series||[U.S.] Bureau of Mines. Technical paper 17|
|LC Classifications||TN1 .U6 no. 17|
|The Physical Object|
|Number of Pages||20|
|LC Control Number||12035962|
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).
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). 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.