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CYCLE TIME AND YARDAGE OUTPUT OF POWER SHOVELS ON HIGHWAY GRADING

ONE OF THE OLDEST TYPES OF MECHANIZED EXCAVATION EQUIPMENT PRESENTLY FOUND IN EVERYDAY USE IS THE POWER SHOVEL. THIS VERSATILE TOOL IS FUNCTIONALLY THE SAME TODAY AS 40 YEARS AGO. MANY TECHNOLOGICAL IMPROVEMENTS HAVE BEEN MADE IN ITS CONSTRUCTION. IT HAS ALSO INCREASED IN SIZE AND THE LRGER UNITS COMMON TO THE POSTWAR CONSTRUCTION ERA DWARF THEIR EARLY PREDECESSORS. THERE ARE MANY VARIABLES WHICH AFFECT SHOVEL PERFORMANCE. YET, EVEN THOUGH IT CONTINUES TO BE A PRINCIPAL TOOL FOR EXCAVATING AND LOADING ROCK AND OTHER MATERIALS, THERE ARE STILL MANY GAPS IN OUR TECHNICAL KNOWLEDGE OF THE VALUES OF THE FACTORS INFLUENCING PERFORMANCE. A POWER SHOVEL GRADING OUTFIT ORDINARILY HAS A NARROW RANGE IN HOURLY COST OF OPERATION REGARDLESS OF WHETHER THE SHOVEL PRODUCES AT A HIGH OR LOW RATE. THE SHOVEL IS THE PRIMARY PRODUCER, ALL PRODUCTION DEPENDS ON IT AND UNIT COSTS WILL GENERALLY VARY INVERSELY WITH THE QUANTITY PRODUCED PER HOUR. THEORETICALLY, A POWER SHOVEL CAN OPERATE CONTINUOUSLY, YET IT IS ONLY DURING SHORT INTERMITTENT PERIODS THAT THE AVERAGE SHOVEL IS ACTUALLY OPERATED IN SUCH A MANNER. THE GAP EXISTING BETWEEN THEORETICAL AND ACTUAL PERFORMANCE CAN BE REDUCED THROUGH IMPROVED PRACTICES RESULTING FROM A BETTER UNDERSTANDING OF THE NATURE AND MAGNITUDE OF THE FACTORS ASSOCIATED WITH THE OPERATION. SHOVEL PERFORMANCE CAN BE IMPROVED BY: (1) REDUCING OR ELIMINATING OVERSIZE MATERIAL, (2) POSITIONING THE SHOVEL TO OBTAIN OPTIMUM HEIGHT OF FACE AND SWING ANGLE IN THE DIGGING AREA, AND (3) PROPER SPOTTING OF TRUCKS TO PERMIT THE MINIMUM SWING ANGLE OUTSIDE THE DIGGING AREA. SHOVEL OWNERS SHOULD CAREFULLY APPRAISE THEIR OPERATIONS IN LIGHT OF DECREASED UNIT COSTS THAT CAN RESULT FROM PROPER JOB PLANNING. /AUTHOR/

  • Supplemental Notes:
    • Vol 26, No 6, PP 23-32, 10 FIG, 4 TAB
  • Authors:
    • Kilpatrick, M J
  • Publication Date: 1956-7

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Filing Info

  • Accession Number: 00219453
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: May 29 1972 12:00AM