Integral Logistics Management — Operations Management and Supply Chain Management Within and Across Companies

5.7.3 Exercise: Theory of Constraints

Intended learning outcomes: Explain an example of the theory of constraints, whereupon you produce two products, which use the machine capacity of three machines with a certain load. Identify and speed up the bottleneck.



You produce two products A and B, which use the machine capacity of your production according to the following table:

If per working day (eight hours), you start producing three products A and five products B, what will happen? What will the buffer in front of machine II look like after one week (five working days)? What measures do you suggest to take if you cannot invest any money?

The capacity of machine II is not sufficient: (3 * 1.5 hours) + (5 * 1.0 hours) = 9.5 hours. Therefore, the buffer in front of machine II will fill with the speed of 1.5 hours of workload per day, which is equivalent to five products A per week. To reduce work-in-progress, the company should decide to release fewer production orders, e.g., for two products A and five products B, per working day only.

A consulting firm offers to speed up your machines, so that the time it takes to machine any product is reduced by a quarter of an hour. To which machine would you apply this measure first, to which next? (Your only objective is to increase the amount of production.)

The bottleneck is machine II, so it would be desirable to increase its speed. After implementing the consulting firm’s measures, the work on products A and B takes (3 * 1.25 hours) + (5 * 0.75 hours) = 7.5 hours. Machine I with a workload of 5 * 1.6 hours = 8 hours will become the new bottleneck.




Course section 5.7: Subsections and their intended learning outcomes

  • 5.7 Scenarios and Exercises

    Intended learning outcomes: Disclose master scheduling for product variants. Calculate the quantity available-to-promise (ATP). Examine an example of the theory of constraints. Elaborate the master planning case.

  • 5.7.1 Exercise: Master Scheduling and Product Variants

    Intended learning outcomes: Determine the degree of overplanning of the number of variants in in the master production schedule (MPS).

  • 5.7.2 Exercise: Available-to-Promise (ATP)

    Intended learning outcomes: Calculate the quantity available-to-promise (ATP), whereupon the master production schedule as well as a list of customers’ orders that have already been promised are given.

  • 5.7.3 Exercise: Theory of Constraints

    Intended learning outcomes: Explain an example of the theory of constraints, whereupon you produce two products, which use the machine capacity of three machines with a certain load. Identify and speed up the bottleneck.