Question

How could the drum buffer concepts from Critical Chain Portfolio Management be applied to this problem?

Answer 1

Similar to CCPM for one project, the formal steps necessary to apply CCPM to multiple project portfolios include:

1. Identify the company resource constraint or the drum, the driving force behind multiple project schedules. Determine the constraint, look at the portfolio as the project – look for the constraint that most effects the performance of the overall system.

2. Exploit the resource constraint—a. Preparing a critical chain schedule for each project independently b. Prioritize the projects for access to the drum, or constraining resource –Senior project engineersc. Create the multi-project resource schedule, based on priority and the desire to maximize project development performance.

3. Subordinate the individual project schedules by—

a. Scheduling each project to start based on the drum schedule

b. Designate the critical chain as the chain from the first use of the constraining resource to the end of the project

c. Insert capacity constraint buffers (CCBs) between the individual project schedules, ahead of the scheduled use of the constraint resource. This action protects the drum schedule by ensuring the input is ready for it.

d. Resolve any conflicts if the creation of CCBs adversely affects the drum schedule

e. Insert drum buffers in each project to ensure that the constraint resource will not be starved for work. The buffers should be sited immediately before the use of the constraint resource in the project.

4. Elevate the capacity of the constraint resource; increase the drum capacity for future iterations of the cycle.

5. Go back to step 2 and reiterate the sequence, improving the operations flow and resource constraint levels each time.