A Reference Guide to Mining Machine Applications
Purpose of Mine Evaluation • Confi Confirm rm that that min minee is getti getting ng maxi maximu mum m valu valuee from from its its inv inves estme tment nt in Cat equipment. • Help Help mine mine set and achiev achievee new new benchm benchmark arkss for for safety safety,, effi efficie ciency ncy and profitability.
Key Factors to Review • Mach Machin ine/ e/sy syst stem em sizi sizing ng and and sele select ctio ion. n. • Job set-up. • Operating te techniques. • General si site conditions. • Haul aul road road des design ign and and mai mainten ntenan ancce.
Trucks Performance Benchmark • Exchange time − Target. . . . . . . . . . . . .42 seconds − Acceptable. . . . . . . . .54 seconds
Trucks Load Placement • Cente Centerr load load abo above ve hoi hoist st cyl cylin inde ders rs and and alo along ng bod bodyy cente centerl rlin ine. e. • Mini Minimi mize ze mate materi rial al on head headbo boar ardd. • Mini Minimi mize ze spi spillllag agee from from sid sides es,, corn corner er,, rear rear.. • Alwa Always ys targ target et 66% 66% - 33% 33% loa loadd spl splitit on fron front/ t/re rear ar axle axles. s. Correct Loading Incorrect Loading
Correct Loading
Incorrect Loading
Trucks Positioning • Loader operator spots truck. • Position for fastest cycle times. − Wheel loaders - 45° − Other loading tools - angle varies
• Keep rear tires off pile. • Minimize wait time.
Trucks Other Tips • Safety − Apply parking brake
• Body − Check liner plate wear and
body pad alignment
• Tires − Inspect tire condition − Check TKPH/TMPH ratings
Loading Tool Selection Rope Shovel
Front Shovel
Mass Excavator Wheel Loader
Cycle time (seconds)
28-32
27-30
24-28
30-40
Fill factor (%)
100-105
90-100
90-110
90-110
Pass match
3-4
4-6
4-6
4-6
Favorable conditions
Single face Stable level floor Wide benches Well-shot material
Selective digging Tight area & material Poor floor
Truck below HEX Tight area & material Short swing
Level, dry floor Well-fragmented material Lower face profile Multi-face loading
Unfavorable conditions
Poor underfoot
Excessive tramming Low benches
High/unstable benches Excessive tramming Low angle of repose material
Poor/wet underfoot Tight load areas
Rope Shovels Performance Benchmarks • Cycle time − 28-32 seconds (31-second average)
• Bucket fill factor - well shot rock − 100-105%
• Pass match − 3-4 passes
Rope Shovels Site Conditions • Optimum bench height − Top of boom sheeves
• Best applications − Single face, correct height − Wide benches − Well-shot material
• Unfavorable conditions − Poor underfoot
Rope Shovels Tips • Maintain maximum swing - 70-90°. • Keep floor clean. • Monitor power cable maintenance. • Never operate a bare edge.
Hydraulic Front Shovels Performance Benchmarks • Cycle time − 27-30 seconds (28-second average)
• Bucket fill factor - well shot rock • 90-100% • Pass match − 4-6 passes
Hydraulic Front Shovels Site Conditions • Optimum bench height − Just above boom/stick pivot
• Best applications − Selective digging, multiple targets − Tight load area and materials − Poor underfoot
• Unfavorable conditions − Excessive tramming − Low benches
Hydraulic Front Shovels Tips • Strip top, load from center. • Keep tight digging zone. • Avoid digging too far into face. • Watch for high, unstable benches. • Load from left. • Avoid excessive prying. • Maximize tip contact. • Always have defined dig pattern R to L or L to R and maintain pattern.
Hydraulic Backhoes (Mass Excavation) Performance Benchmarks • Cycle time − 24-28 seconds (26-second average)
• Bucket fill factor - well shot rock − 90-110%
• Pass match − 4-6 passes
Hydraulic Backhoes (Mass Excavation) Site Conditions • Optimum bench height − Length of stick or distance between truck siderail and ducktail
• Best applications − Truck below excavator − Tight load area, tight material − Short swing - 60°
• Unfavorable conditions − High benches − Excessive tramming − Low angle of repose material
Hydraulic Backhoes (Mass Excavation) Tips • Watch for excess bench height. • Keep tight digging zone and swing angle. • Remove farthest pass during truck exchange and maintain “Key Cut” (pass in front of inside track) to establish straight wall for next cut. • Avoid digging too far into face. • Keep cut in line with inside track, no more than 45° over outside track. • Watch for poorly blasted toe.
Wheel Loaders Performance Benchmarks • Cycle time − 30-40 seconds (38-second average)
• Bucket fill factor - well shot rock − 90-110%
• Pass match − 4-6 passes
Wheel Loaders Site Conditions • Optimum bench height − Bucket hinge pin height at maximum lift
• Best applications − Level, dry, smooth, firm floors − Good drainage − Well-fragmented material − Lower face profile − Multi-face loading
• Unfavorable conditions − Poor or wet underfoot − Tight load areas
Wheel Loaders Tips • Enter pile straight on. • Keep frame straight when digging. • Lift bucket before crowding. • Horizontal lift arms when bucket is full. • Keep time in face below 12 seconds. • Position loader 1.5 wheel turns from face to truck. • Never operate a bare edge.
Motor Graders Blade Position • Keep top of moldboard 50 mm ahead of cutting edge. • Keep edge at 90° angle to surface. • Maintain constant tip angle.
Motor Graders Blade Angle • Use widest pass width. • Increase blade angle if material flows around leading edge. • Use 10° blade angle for Grader Bit System or serrated edge.
Motor Graders Other Tips • Grade in 2nd or 3rd gear. • Rip in 1st gear with all machines. • Always keep edges sharp for better penetration. • Change edges prior to moldboard damage.
Track-type Tractors Ripping Tips • Rip downhill. • Rip in same direction scrapers will load. • Watch speed. − 1.5-2.5 km per hour
• Position tip properly. − Begin with tip rearward − Pull forward after penetration − Shank lies backward while ripping
Track-type Tractors Dozing Tips • Use slot dozing. • Use slopes. • Steer with blade. • Minimize corner loading, prying, impact. • Maintain steady pressure. • Position blade properly. − Tilt forward − Lay blade back when half full − Continue racking blade back as it fills
Track-type Tractors Other Tips • Reinforcing ribs on penetration ripper tip must face up. • Ensure proper installation of GET. • Never operate bare shank. • Avoid excessive tramming. • Watch for missing or loose track hardware.
Scrapers Performance Benchmarks • Load time - open bowl/push-loaded WTS. − Target . . . . . . . . . . . . . . 24-30 seconds − Average . . . . . . . . . . . . 36-43 seconds
• Shorter time for tandem. • Longer time for single powered.
Drills Performance Benchmarks (25,000-40,000 lb/111.25-178 kN pulldown)
• Depths − Multi-pass . . . . . . . . .up to 40 m/43 yd − Single-pass . . . . . . . 10-12 m/11-13 yd
• Hole sizes − 100-200 mm/3.9-7.8 in
• Rotation speeds − Coal . . . . . . . . . . . . 120-150 rpm − Hard rock . . . . . . . .100-120 rpm
• Penetration − Coal . . . . . . . . . . . . 40-60 m/hr/43.7-65.6 yd/hr − Hard rock . . . . . . . .10-30 m/hr/10.9-32.8 yd/hr
Drills Performance Benchmarks (40,000-60,000 lb/178-267 kN pulldown)
• Depths − Multi-pass . . . . . . . . . up to 60 m/65.6 yd − Single-pass . . . . . . . .12-16 m/13-17 yd
• Hole sizes − 150-250 mm/5.9-9.8 in
• Rotation speeds − Coal . . . . . . . . . . . . . 100-130 rpm − Hard rock . . . . . . . . . 80-110 rpm
• Penetration − Coal . . . . . . . . . . . . . 40-80 m/hr/43.7-87.4 yd/hr − Hard rock . . . . . . . . .10-40 m/hr/10.9-43.7 yd/hr
Drills Performance Benchmarks (60,000-110,000 lb/267-489.5 kN pulldown)
• Depths − Multi-pass . . . . . . . up to 100 m/109 yd − Single-pass . . . . . .14-18 m/15-19 yd
• Hole sizes − 200-350 mm/7.8-13.7 in
• Rotation speeds − Coal . . . . . . . . . . . .80-110 rpm − Hard rock . . . . . . . 70-90 rpm
• Penetration − Coal . . . . . . . . . . . 40-100 m/hr/43.7-109.4 yd/hr − Hard rock . . . . . . . 10-50 m/hr/10.9-54.6 yd/hr
Drills Performance Benchmarks (Track drills)
• Depths − Multi-pass . . . . . . . . . up to 50 m/54 yd − Single pass . . . . . . . . 8-10 m/8.75-10.9 yd
• Hole sizes − up to 150 mm/5.9 in
• Rotation speeds − Coal . . . . . . . . . . . . . 80-120 rotary − Hard rock . . . . . . . . . up to 40 rpm hammer
• Penetration − Coal . . . . . . . . . . . . . 30-50 m/hr/32.8-54.6 yd/hr − Hard rock . . . . . . . . . 10-30 m/hr/10.9-32.8 yd/hr
Drills Favorable Site Conditions • Level floor. • Unbroken ground. • Minimal water ingress. • Regular pattern spacing. • Limited tramming. • Adequate maneuvering space.
Drills Operating Tips • Watch for excessive vibration. • Avoid drill plunging. • Avoid excessive pulldown pressures. • Avoid excessive rotation speeds. • Set bailing velocity correctly. • Monitor chip size. • Level drill correctly. • Maintain flat floor.
Haul Road Design Horizontal and Vertical Alignment • Design corners and crests that allow excellent visibility at normal travel speeds. • Use worst-case scenarios.
1
10
Haul Road Design Cross-slope • Flats − Apply minimum slope to maintain drainage − Use constant crossfall when possible
• Grades − Minimal cross-slope required
2° constant crossfall
Haul Road Design Grade • Maintain smooth grade. • Maintain consistent percentage.
Correct
Incorrect
Haul Road Design Corners • Use maximum practical radii. • Employ super elevation for higher speed operations. • Use super elevation >10% with caution.
Haul Road Design Road Width • One way - 3 truck widths. • Two-way straights - 3.5 truck widths. • Two way corners - 4 truck widths.
One-way (Straights/corners) Two-way (In Straights) Two-way (In Corners)
Haul Road Design Bench Width • Truck must clear loader under full acceleration. • Minimum width = machine turning radius + width of safety berm.
Bench Width
Haul Road Design Drainage & Safety Berms • Drainage system - sized to accommodate maximum rainfall. • Berm size - at least one-half wheel height.
1/2 wheel height
Drainage
Haul Road Design Rolling Resistance • Hard, well-maintained road . . . . . . . 1.5% • Well-maintained road with flex . . . . . . 3% • 25 mm/1 in tire penetration . . . . . . . . .4% • 50 mm/2 in tire penetration . . . . . . . . .5% • 100 mm/4 in tire penetration . . . . . . . .8% • 200 mm/8 in tire penetration . . . . . . .14%
Tire penetration
Haul Road Maintenance Rules of Thumb • Begin at face; end at dump. • Pick-up truck travels comfortably at 60 km/hr (37 mph). • OHT travels at reasonable speed. • Remove and repair wet/soft spots. • Consider checkerboard or spot watering on slopes.
Haul Road Maintenance Analysis Tools • Application Severity Analysis (ASA). • Vital Information Management System (VIMS). • Fleet Production and Cost (FPC).
Haul Road Visual Inspection Load Zone • Floor is smooth. • Water removal is adequate. • Debris is cleared away. • Trucks don’t drive over rocks. • Trucks leave under full, continuous acceleration. • Trucks return without making tight, high-speed turns.
Loading Zone
Haul Road Visual Inspection Main Haul Road • Road is free of puddles, potholes, ruts, gullies. • Passing room is adequate. • Corner radius allows safe operation at high speed. • Spillage is removed quickly. • No rubber deposits on tight, rocky turns. • High braking forces not necessary on corners. • Expected road speeds are achieved.
Haul Road Visual Inspection Dump Zone • Floor is smooth. • Trucks enter at high speed, parallel to edge. • Trucks brake in straight line, then turn and stop to reverse to dump. • Safety berms are regulation height. • Is dump stable enough to dump over safely or should you dump short and push off.
Discussion Topics for Mine Managers Bucket Fill Factors • Higher fill factors improve productivity and reduce cost per ton. • Achieve higher fill factors through: − Better fragmentation − Correct bucket selection − Correct GET selection and maintenance − Correct bench heights − Correct loader orientation to face
Discussion Topics for Mine Managers Loader Cycle Times • Faster cycle times improve productivity and reduce cost per ton. • Achieve faster cycle times through: − Correct orientation to face − Improved floor conditions − Correct truck placement − Improved material condition
Discussion Topics for Mine Managers OHT Road Speeds • Higher OHT road speeds improve productivity and reduce cost per ton. • Achieve faster speeds through: − Smooth roads - load to dump − Reduced rolling resistance − Better road design − Better payload control
Discussion Topics for Mine Managers Cat Software Tools • Compare actual and theoretical: − Grade speeds − Cycle times − Total productivity
• Analyze impact of changes: − Haul road speeds − Bucket fill factors − Truck exchange time − Fuel consumption − Component life − Tire life
Discussion Topics for Mine Managers Hauling System Application Zones
Dozers: 0 to 100 m (0 to 350 ft)
*Load and Carry: 50 to 120 m (150 to 400 ft)
*Scrapers: 120 to 1200 m (400 to 4000 ft)
*Articulated Trucks: 120 to 1200 m (400 to 4000 ft)
*Rear Dump Truck: 120 to 1500 m (400 to 5000 ft)
*Underfoot, material type, production rate & operator skill also affect system selection
*Wagon/Hauler: 1200 to 10 000 m (4000 to 35,000 ft)
Discussion Topics for Mine Managers Support Equipment • Correct use of support machines can: − Enhance safety − Improve productivity & extend life of production equipment − Extend tire life − Maximize haul road life
Reference Material Print • Cat Performance Handbook • A Reference Guide for Mining Machine Applications (AEDK0391) • Handbook of Ripping (AEDK0752) • 5130/5230 Applications Guide (AEDK0128) • H-Series Motor Grader Application Guide (AEGQ0945) • 994 Bucket Selection Guide (AEDK0268) • Making the Most of Scraper Potential (AEGQ2380) • Optimum Scraper Load Time (AEGC0195) • GET Inspection & Maintenance Guide (PEXT8033) • GET Service Guide (PEGP7030)
