Blast designs to improve dragline stripping rates. Final report

Technical Report · Mon Nov 01 04:00:00 EST 1982

OSTI ID:6640953

Crosby, W A; Workman, L; Lombardi, J A; Simos, J G

Field tests of blasting techniques to improve dragline productivity were undertaken at a midwestern strip coal mine. The program intent was to demonstrate the potential for increased dragline productivity using explosive casting. Explosive casting is the displacement of overburden directly into a spoiled condition. During the field tests approximately 16 percent of the overburden associated with any given unit of coal was explosively cast into its final spoils position. The test program realized stripping efficiencies greater than the noted 16 percent (cast) and 2 percent (dragline cycle improvement). An additional 7 percent productivity was attributable to changes introduced into the two-seam mining method employed at the test mine. Historically, the dragline worked 20 to 25 percent of its time in a chop down mode as opposed to more efficient below grade underhand excavation. The test program explosive casting of muck was characterized by a compensating vertical highwall drop. The highwall drop void was filled so that a level working surface for the dragline was established (without tail room obstruction). The filling was done by dozers. The fill material used was the No. 6 Coal (upper seam) overburden normally taken in the dragline chop down activity. Elimination of the dragline chop down activity and replacement of this activity with the more efficient underhand excavation mode led to another 7 percent increase in dragline productivity.

• Research Organization: Woodward-Clyde Consultants, Englewood, CO (USA)
• DOE Contract Number: AC01-77ET11239
• OSTI ID: 6640953
• Report Number(s): DOE/ET/11239-1; ON: DE83003095
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
012000* -- Coal
Lignite
& Peat-- Mining
COAL MINING
COMMINUTION
DATA
DRAGLINES
EARTHMOVING EQUIPMENT
EQUIPMENT
EXPERIMENTAL DATA
EXPLOSIVE FRACTURING
FIELD TESTS
FRACTURING
INFORMATION
MATERIALS HANDLING EQUIPMENT
MINING
NUMERICAL DATA
OVERBURDEN
PRODUCTIVITY
SURFACE MINING
TESTING