Cable Shovel Costs ©Dr. B. C. Paul 2000

Do the Cable Shovel l Have a 12 yard P+H Examine Cable Shovel Cycle Time Chart Predicted 26 seconds

Check Loading Time l 4 Dippers * 26 seconds = 1.73 minutes l Gives 10 minute Truck Cycle This suggests that 3 truck need should perhaps be re-evaluated l 422,000 tons per truck with min/cycle l Adjust to 10 minute cycle 422,000*11.08/10 = 467,710 tons

Continuing Analysis of Truck Loader Balance l Not Enough - But I assumed 85% loader availability and Cable Shovel should do 95% 467,710 tons * 0.95/0.85 = 522,735 tons l Running Just Two Trucks and Cutting Load Time will impact bunching - since I may be about ready to change my fleet balance - I’d better check

Checking Match and Bunching l 2*1.73/10 = Match Factor Very badly under-trucked l Bunching Losses are minor 99.4% Production Capacity will be higher than thought l Get Run-Time Needed for Production We’ll do it from the loader end since that is our subject

Production Time l yd3/pass counting fill factor l 26 seconds per pass l 151,200 minutes per year l Max passes and tonnage 151,200*60/26 = 348,923 passes/year 348,923*11.15*2600/2000= 5,057,000 tons/year

Production Limiting Factors l We will have only 95% utilization due to mine operating Schedules l The Cable Shovel will be available 95% of Scheduled Time l Operators will only actually work 83% of the time

Finishing Operating Hours l We are under-trucked only 34.6% of the time will there be a truck there to load l We will have trucks bunched 99.4% l 5,057,000*0.95*0.95*0.83*0.346 *0.994 = 1,303,000 tons l 1 million tons needed 1934 operating hours per year

Getting Cost Of Cable Shovel Loading l About 2 million to buy l Add about 5% for extras $100,000 l Erection cost $110,000 l Freight Cost 16 cents/ton mile 300 miles from Milwaukee about $17,000

More Ownership Cost l Ballast needed about 173,000 lbs $210/ton for steel punchings $18,000 l Total Cost $2,245,000 on site l Life is 100,000 hours plus l With Scheduled run time this is over 50 years l People often depreciate cable shovels over 20 years just because the real life doesn’t work well in calculations

Ownership Cost Continued l $2,245,000 * 0.16 (15% over 20 years) = $359,000/year l Taxes and Insurance 6% of average annual investment 21/40*0.06*2,245,000 = $70,718 l Tax Advantage 20 year straight line $2,245,000/20*.4 = $44,900

Ownership Cost l Total $385,000/year l By Contrast FEL was $194,000/year

Operating Cost l Repair Cost depends on Digging Conditions Very Hard 5 cents/ton Hard 4 cents Medium 3 cents Easy 2 cents We used medium 3 cents for 1 million tons $30,000/year

More Operating l Some add wear parts but usually not significant l Electric Power 0.6 KWH/yd3 2,600/2,000 = 1.3 tons/yd3 0.6 KWH/1.3 = 0.46 KWH/ton at 4.5 cents/KWH = 2.1 cents/ton $21,000/year

Labor Costs l Labor 24.86/hr for operator Often also have an oiler may be lower paid but some companies put everyone on same scale we’ll use 20/hour 1934 hours scheduled 1934*44.86 = $86,760/yr of 8.6 cents/ton

Total Cable Shovel Costs l Operating 13.7cents/ton $137,000/year l Contrast to $179,040/year for FEL Cable Shovel was eaten up by labor that was under-trucked l Total Cost is $522,000/year or 52.2 cents/ton l FEL was 38.5 cents/ton

Cable Shovel Saved on Trucking Costs l Only Needed 2 Trucks instead of 3 but I will have more run time so they will wear out in 10 years - not 12 l $787,000 over 10 years *787,000 = $156,810/year

Savings l Tax and Insurance and Tax Advantage - we’ll just adjust for 2 trucks instead of 3 net 10K savings actually some variation in life ignoring l $147,000/year this way vs. $222,000/year $75,000/year savings l Operating Costs were already per hour - may have saved just slightly on bunching

Conclusion l Have $447,000 with truck savings vs. $358,000 with FEL - obviously the cable shovel is out unless we can better use its capacity (we only had enough trucks to load 35% of the time vs. about 75% with the FEL)