Drill Bit Replacement OptQuest Solution

Note:

Except where indicated, this example uses the recommended Crystal Ball run preferences. See Setting Crystal Ball Run Preferences.

  With Drill Bit Replacement.xls open in Crystal Ball:

  1. Start the OptQuest wizard.

    As you click Next to step through the problem, note:

    • The objective is to maximize the mean profit per month.

    • The problem has no requirements or constraints.

    • This problem has one decision variable, with search limits of 1 and 50.

  2. Run the optimization.

Figure 59, Drill bit replacement model optimization results, following, shows the OptQuest results. The best solution is to replace the drill bit approximately every 19.9 hours.

Figure 59. Drill bit replacement model optimization results

Drill bit replacement model optimization results.

Figure 60, Drill bit replacement forecast chart and statistics, following, shows the OptQuest forecast chart and statistics for the simulation of this solution. The profit per month has a relatively large standard deviation compared to the mean (coefficient of variability=0.30); thus, it is likely that the true profit/month is significantly higher or lower than the mean objective value.

Figure 60. Drill bit replacement forecast chart and statistics

Drill bit replacement forecast chart and statistics.