Definition of secondary blasting - Mindat.org
Definition of secondary blasting Irrespective of the method of primary blasting employed, it may be necessary to reblast a proportion of the rock on the quarry floor so as to reduce it to a size suitable for handling by the excavators and crushers available. Two methods of secondary blasting of rock …
Secondary blasting | Article about secondary blasting by ...
In secondary blasting, explosive denotation release a huge amount of energy which results to rock shattering and scattering and consequently high fly rocks. The labour cost for secondary blasting can be expressed as a percentage of the labour cost for primary mucking.
Secondary Blasting Standard Operating Procedure
Mar 01, 2015 · Definitions Secondary blasting - blasting of oversize rocks usually from previous blast Popping – secondary blasting where an explosive charge is placed in a hole drilled to center of rock then stemmed for blasting Plaster or Mud blasting – secondary blasting where explosives are on top of the boulder and packed in place with mud or clay for blasting Boulder - any rock which due to its …
(PDF) ROCK BLASTING FOR MINING - ResearchGate
After a production blast, a secondary blast may be required to reblast a portion of the rock to reduce it to a size fit for handling by the machines and equipment available (Balasubramanian, 2017...
breakage of rock – Mining and Blasting
Oct 12, 2012 · Contemplation of Blast Design: Blast designing is not a science, but knowledge, experience, studying and analyzing past practices in relation to rock strata & geology etc., makes blaster to achieve perfection. Thus, for a blaster, valuable tool is the file of blast reports that he builds as he gains experience.
Chapter 9 GENERAL ROCK REMOVAL - National Park Service
SECONDARY BLASTING Bench blasting ideally reduces all rock to a desired rubble size range. This is basic in order to facilitate handling of rubble or muck to meet limitations imposed by equipment, such as bucket size, or to produce a usable material.
H BLASTING IN SURFACE EXCAVATION
Secondary blasting can be done by pop shooting (blockholing) and plaster shooting (mudcapping). Shaped charges are sometime used in secondary blasting, but this is much more expensive.
Secondary breaking strategy for block 4 at De Beers—Finsch ...
Concussion blasting, where concussion bombs and lay-on charges are used to break hang-ups and boulders. Drill and blast methods, where holes are drilled in large rocks and charged manually with explosives. Emulsion secondary blasting, which is a new project in use at Koffiefontein mine from African Explosives Limited.
Drilling and blasting - Wikipedia
Drilling and blasting is the controlled use of explosives and other methods such as gas pressure blasting pyrotechnics, to break rock for excavation. It is practiced most often in mining, quarrying and civil engineering such as dam, tunnel or road construction.
Chapter 8 BLAST DESIGN - National Park Service
The rock will move forward normally to the rows of holes. If the holes are fired in oblique rows as in Figure 8-5, the rock mass would be thrown to the right during blasting. (Figure 8-4) Typical bench cut with two free faces and fired with one delay per row. (Figure 8-5) Direction of throw of blasted rock.
Rock blasting for mining - SlideShare
Jul 28, 2017 · Rock blasting for mining 1. 1 ROCK BLASTING FOR MINING by Prof. A. Balasubramanian Centre for Advanced Studies in Earth Science University of Mysore Mysore-6 2. 2 Objectives: You are all aware that Mining is a major economic sector of any country. Mining is a geotechnical industry.
Drill and Blast Method - railsystem
Drill and Blast Method. Drill and blast method is mostly used method for the excavation throughout the world. The method can be used in all types of rocks and the initial cost is lower than the mechanical method like TBM. This tunneling method involves the use of explosives.
Drilling and Blasting of Rocks - E. Lopez Jimeno, C. Lopez ...
The Geomining Technological Institute of Spain (ITCE), aware of this progress and of the importance which the breakage process has acquired in mining and civil engineering projects, has ordered the publication of Drilling and Blasting of Rocks.
Taking precautions against flyrock | Business Queensland
avoiding overcharging when conducting secondary blasting. Previous excavations and the driller of the blast holes can provide important information about the rocks structure. The area surrounding a blast site must be inspected to determine the distances to residences, roads, …
Engineering Geology Field Manual - Volume II - 2nd Ed ...
rocks similar to the typical rocks listed in table 19-1. Denser rocks such as basalt require smaller ratios (higher powder factors). Lighter materials such as some sandstone or bituminous coal can be blasted with higher ratios (lower powder factors). The hardness or brittleness of rock can have a significant effect on blasting results.
drilling and blasting cost – Mining and Blasting
May 19, 2011 · Blasting is only the first step in the production process for mines and quarries and the costs of this first step is normally only 8% to 12% of the total costs. The total product costs are composed of: drilling, blasting, secondary breakage of oversize, digging, haulage, crushing. Blasting affects every step in the production cycle.
Sedimentary rock - Wikipedia
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of small particles and subsequent cementation of mineral or organic particles on the floor of oceans or other bodies of water at the Earths surface. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment ...
FAQ – Royex Rock Breaking & Excavation – Safe, Reliable ...
Improved secondary blasting in pit due to low fly rock risk High precision blasting for dimensional quarries, less wire sawing or downstream cutting Reduced safety distances for machinery and personnel No track and trace required