How to draw and edit relationships in the Gantt Chart
The Gantt chart is at the center of most scheduling software, where analysis by schedulers and the project team takes place. The Gantt chart is popular as it offers a visual display of how a project is progressing instead of a lot of text and numbers.
Primavera P6 Professional supports a quick and efficient way to draw a relationship assignment directly in the Gantt chart. Primavera P6 supports all four relationship types; Finish to Start (FS), Finish to Finish (FF), Start to Finish (SF) and Start to Start (SS). Let’s take a closer look at how easy this feature is to use.
In our example project of pipe inspection and repair, we have just inserted a new activity for the order & delivery of pipe adaptors. There are no relationships assigned to this activity, so we need add some. In this case, we are going to assign a Finish to Start (FS) predecessor and successor relationships to A1080 – Order & Delivery Adapters.
By hovering the cursor at the finish end of the A1050 – Pipe Inspection activity, the cursor will change from the default pointer to a staggered or jagged arrow as shown below in Figure 2.
By left-clicking the mouse we can drag the cursor to the start of A1080 – Order & Delivery Adapters and drop it there when the blue relationship arrow appears, as shown in Figure 3 belo.
A tooltip will enable us to select the type of relationship (in our case FS) that we require before releasing the mouse key.
By continuing the process, we move the cursor to the finish of A1080- and when the jagged cursor appears drag and drop to the start of A1090- Pipe & Adapter Installation.
By quickly recalculating with the F9 function key, the final schedule is displayed below in Figure 4.
The predecessor to A1080 – Order & Delivery Adapters is A1050 – Pipe Inspection and the successor is A1090 – Pipe & Adapter Installation.
Primavera P6 Professional will only allow you to insert one-to-one individual relationships directly onto the Gantt chart, but it does support all four relationship types. These are created as follows:
- FS – Draw from the right edge of the predecessor to left edge of the successor.
- FF – Draw from the right edge of the predecessor to right edge of the successor.
- SF – Draw from left edge of the predecessor to right edge of the successor.
- SS – Draw from the left edge of the predecessor to left edge of the predecessor.
Primavera P6 also allows editing of relationships in the Gantt chart by hovering the cursor over a relationship line until an upward arrow appears. When the ↑ appears if you double left-click, you will bring up the edit relationship dialog. In this dialog, you can delete the relationship, change the type of relationship, or define a lag.
There, I said editing relationships in the Gantt chart was easy!