1.7. Estimation of Cycle Time

Try these first

1. 1.

   What is cycle time?

   Hint

   Think about all the steps involved in using a scraper.

2. 2.

   What does ADBT stand for?

   Hint

   Focus on the speed-related components.

3. 3.

   What are the components of cycle time?

   • Loading
   • Hauling
   • Dumping
   • Hauling
   • Returning
   • Spotting
   • All of the Above

   Hint

   Think about each step involved in using the scraper.

4. 4.

   True or False: Loading a scraper to maximum capacity will always increase its productivity.

   • True
   • False

   Hint

   Consider how material dynamics work in a confined space.

5. 5.

   Calculate the cycle time if a scraper has the following times: LT = 0.8 min, HT = 3.5 min, DT = 1.2 min, RT = 2.3 min, ST = 0.5 min, TT = 0.25 min. Consider also ADBT = 0.15 min. What is the total cycle time?

   Hint

   Add all the specified times together following the formula.

6. 6.

   A project has two haul routes, one taking 5 min to traverse and the other taking 3 min. The loader takes 2 min, dump time is 1 min, and return time is 4 min. What can be done to reduce the cycle time?

   Hint

   Identify the longest process and see how you can enhance its efficiency.