2.2.1. Back-Track Loading

Try these first

1. 1.

   Define cycle time.

   Hint

   Think about what actions a scraper performs in its operation.

2. 2.

   What is fixed time?

   Hint

   Consider the components of cycle time that remain constant.

3. 3.

   What does cycle time include?

   • Only loading time
   • Loading
   • hauling
   • dumping and more
   • Just haul time

   Hint

   Think about all the operations that scrapers perform.

4. 4.

   True or False: Fixed time is dependent on the distance travelled.

   • True
   • False

   Hint

   Recall the definitions of fixed vs. variable time.

5. 5.

   A scraper has a load capacity of 20 m3. If it takes 3 minutes to go from 0 to 80% capacity and then the loading slows significantly, explain how you would adapt the loading approach.

   Hint

   Think of the loading growth curve and its implications.

6. 6.

   Calculate the expected cycle time of a scraper given varied haul distances and understand its impact on variable time.

   Hint

   Explore calculations involving variable time elements.