Chapter 22 is the key to understand the critical chain
method. Rather than scheduling projects based solely on the task of critical
path, the project should also consider constraints of resources working on
multiple projects. How can new development projects at any construction firm
account for “bottleneck” resources necessary to complete multiple projects?
Critical Chain project management provides us with various
stages in the current enhancement to the Project Management Body of knowledge.
The main difference between the critical chain and the critical path is the insertion
of resource colonies. The critical chain project management advances the project
plan by guaranteeing that is feasible and protected from rational common cause
variation or any uncertainties and this is done by including buffers at the end
of activity paths. The inclusion of buffer ensures the protection of the
complete project completion on the critical chain route and critical chain is retained
from path amalgamation by nurturing buffers. The Measurement and conclusion
making is enhanced and improved project control is achieved from buffer
management. The exclusion of data driven activity performance and multitasking
and other changes in resource behavior were necessary for implementation of
Critical chain project management. The cost and schedule records were improved
in projects that used CCPM. The projects using other planning methods took
twice the time to complete when compared to critical chain project management.
Critical chain project management was developed from the
theory of constraints. The change and uncertainty in duration of activity is
directly addressed by Critical path project management planning and control
process. Overall duration of the project is reduced by development and
management of project performance to meet or to exceed reduced activity times.
Wafers of semiconducting material were produced by a company
named Harris semiconductor. 8″ wafer plant was built using critical chain
project management. 250 million dollars were invested for the wafer plant. 2
million dollars per day was the revenue from such a plant as the cost of the
raw material is low. It took the company thirty months to build a new wafer
plant of 6″. It took 46 months to start the plant to run to ninety percent of
its capacity. Harris took fourteen months to build the plant and bring it up to
production of ninety percent capacity, their results were presented at a
conference that was hosted by AVARAHM Y GOLDRATT institute.