One comes across a large quantity of information on a Project. It is hard to stay focus on the 2 drivers of the Project duration: Equipment and Piping, i.e.
1) The Critical Path of the Project is Piping.
2) Piping construction starts once Engineering is almost completed.
3) Engineering starts once Equipment purchase orders have been placed.
You will find more details in Chapter 16 of The Guide 2nd edition but above is the essence once must bear in mind at all times.
So one must focus on:
• Placing purchase orders for Equipment in the very first months of the Project.
• The Piping chain, particularly, the timely purchase of all types of materials and long lead ones.
