JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

Course Objectives

To familiarize the students with exploratory and production drilling

including the factors affecting drilling; Various types of the explosives and blasting techniques used in underground and opencast mining are also explained besides blasting in civil constructions projects.

Course Outcomes

Drilling and blasting is primary operation in any mining organization,

student understands various methods of drilling, design and selection of drilling methods. Knowledge about explosives and blasting techniques makes student confident in design of blasting operations in the field.

UNIT - I

Exploratory Drilling: Drilling for exploration and other purposes; diamond drilling- equipment and principal of operation, it’s merits, demerits and limitations; core recovery — single and double tube core barrels; wire line drilling; directional drilling; fishing tools; borehole surveying; borehole logging; novel and special drilling techniques, Horizontal and directional drilling.

UNIT - II

Production Drilling: Various methods and mechanics of drilling -percussive, rotary and rotary percussive. Jack hammer drilling, Top hammer and Down the Hole (DTH) hammer drills. Drillability: Drillabilty studies, Factors affecting drilling- operational parameters (like air pressure, thrust, r.p.m., flushing, bit type and bit geometry etc.) and physico-mechanical properties ( like strength properties, hardness, abrasivity etc.) design and selection of drills; bit wear and reconditioning of drill bits; drill hole economics.

UNIT - III

Explosives: Classification and properties of explosives, Types of explosives – Permitted type, slurry explosives, SMS and PMS, ANFO, LOX, boosters, blasting agents. Mechanics of blasting, alternatives to explosives. Accessories and Tools: Accessories- different types of detonators, safety fuses, detonating cords, relays, NONEL, exploders, sequential blasting machines and other shot firing tools, testing of explosives, storage, transportation and handling of explosives.

UNIT - IV

underground Blasting: Drill patterns for underground excavations (for both coal and metal) and in shafts; solid blasting; smooth blasting, induced blasting, charge ratios, rock fragmentation, dangers associated with underground blasting, blasting economics, gallery

blasting, statutory requirements, computer design of underground blast, precautionary measures, misfires, blown out shot.

UNIT - V

Open Pit Blasting: Blasting in opencast mines, blast design, primary and secondary blasting; accidents due to blast in opencast mines and preventive measures; environmental impacts due to blasting- ground vibrations, fly rocks, dust, fumes, water pollution; Dimension stone blasting, controlled blasting, computer design of opencast blast; statutory requirements. Blasting for Civil Constructions and Trenches: Blasting for road constructions, trench cutting in soft and hard rocks, demolition of buildings etc.,

TEXT BOOKS:

• 1. Roy Piush Pal, Blasting in ground excavations and mines, Oxford and IBH, 1st ed 1993.
• 2. C.P. Chugh, Drilling technology handbook, Oxford and IBH, 1sted, 1977.

REFERENCE BOOKS:

• 1. Roy Piush Pal, Rock blasting effect and operation, A.A. Balkema, 1st ed, 2005.
• 2. D.J. Deshmukh, Elements of mining technology, Vol-1, Central techno, 7th ed, 2001.
• 3. B. Hemphill Gary, Blasting operations, Mc-Graw Hill, 1st ed 1981.
• 4. R.D. Singh, Principles and practices of modern coal mining, New age International, 1st ed, 1977.
• 5. S.K.Das, Explosive and blasting practices in mines, Lovely prakashan, 1st ed, 1993.