1. How to minimize loading time?
2. How to minimize loader cycle time?
Lay-Out of Mining Areas
1. Provide sufficient operating room whenever possible
2. Develop mine standards on typical operation lay-out for major equipment
3. Enforce adherence to the standard designs
4. Strive to improve the practice and the standards
Loading & Dumping
1. Custom design the loading method to maximize loading efficiency by:
a. Maximizing loading rate
b. Minimizing truck/shovel waiting time
2. Use double back-up whenever possible
3. Allow sufficient room for unrestricted maneuvering
Loading Methods
Which Is the Best for You ?
Customize Your Method !!!
Double Back-up
Advantages of Double Back-up
1. Overall swing angles are low
2. Truck wait time used for spotting
3. Dozer clean-up does not require shovel wait
4. Truck travel over spillage is minimized
5. Pockets of material can be selectively mined
6. Faces of irregular shape easy to mine
7. Trail cable is well clear of the bank
Minimize Swing Angle
Cycle Time: CAT 5130
Double Back-up: Problems
1. Greater skill required of truck operator
2. Half of the trucks loaded on the “blind” side
3. Adequate mining area is necessary
4. Not suited to low face work as frequent shovel moves are required
5. As compared to drive-by:
a. Moves require more dozer assistance
b. Pit grade is more difficult to maintain
Single Back-up
1. Caters for restricted mining areas
2. Irregular shaped faces easy to accommodate
3. Pockets of material can be selectively mined
4. Loading on operator side only
5. Trucks easy to spot using bucket as a guide
Drive By
1. Minimum maneuvering for the haulage unit
2. Shovel moves are minimal through the cut
3. Seam surface can be used as a roadbed
4. Pit floor grade is easy to maintain
5. Trucks are not required to reverse thus less tire damage
Hydraulic Shovel Mining Not much different …
Backhoe Mining
Backhoe: Swing Angle
Optimum work zone and the swing angle:
For maximum production, the work zone should be limited to 150 either side of machine center or about equal to undercarriage width.
Trucks should be positioned as close as possible to machine centerline. (Two alternatives shown here).
Should a Loader Haul Material? (In Addition to Excavating It) LHD Mode of Operation
Depends on …
….Haulage Distance?
….Haul Rate?
How Far Should We Haul?
LHD mode operation
Loading: General Comments
1. Minimize shovel / loader swing angle.
2. Minimize truck spotting & exchange time.
3. Provide sufficient room for equipment to maneuver.
4. Keep the bench floor clean and level.
5. Use shovel idle time to prepare the bench / face.
6. Keep the power cable / other support out of the way.
7. Good blasting practice is important.
8. Pay attention to detail:
* Drainage, light, dust, fog, etc….