The work breakdown structure essentially is a decomposition of the work to be completed by the project team in order to successfully accomplish the project objectives and deliverables. It’s a very practical tool to visualise the work that needs to be done, however that is about all it’s useful for. The information provided by the work breakdown structure is not enough to allow the project team to identify any milestones or points of significance in the project. At this stage each element of the project has only been
identified, none of them have been time scheduled, cost estimated or placed in a definitive chronological order, making it difficult to identify any significant milestones. Network scheduling refers to the graphical representation of activities that define the sequence of work in a project. It is an important tool used to visualise the chronological order of activities needed to be completed in order to meet the project deliverables and objectives. The project team decided to use Microsoft project to develop the network schedule for the conveyer belt project.
However before a network schedule could be produced it was necessary to enter some important information into Microsoft project. Firstly the work calendar had to be customised. It was necessary to ensure that work was only completed from Monday to Friday during an 8 hour work day and that all relevant public holidays which would affect work were accounted for. Below in Figure 1 is the work calendar in Microsoft project. Following this the project team could enter the estimated duration of each work package and place them in chronological order.
With the conveyer belt project set to begin on the 4th of January 2010, Microsoft project estimated the project would be complete on the 2nd of February 2012 and would take a total of 530 days to finish. On the following page in Figure 2 is a gant chart produced by Microsoft project which illustrates the schedule of each activity in the project. It is quite clear that the network of the project isn’t very sensitive. Both the gant chart on the previous page and the network diagram at the end of this section show a clear critical path in red.
Although there are some activities with only a few days slack, namely the assembly of preproduction models which only has 5 days slack, the remaining activities in the project not on the critical path have 30 or more days slack. If some of the activities were to delay it isn’t very likely that a lot of critical paths would develop since majority of the activities have a reasonable amount of slack. Utilities documentation is easily the most flexible of the activities since it has the largest amount of slack adding up to 115 days.
Now that the project team had successfully developed a valid network schedule it is more convenient to identify significant milestones in the project. Besides the start and end dates, 4th January 2010 and 2nd February 2012 respectively, the project team was able to identify two other milestones listed below: •Integration First Phase and •System Hard/Software Test The first phase of integration was identified as a milestone since its start date is heavily reliant on so many other activities.
Before integration first phase can even begin, six other activities preceding it must also be completed. In addition to this integration first phase is on the critical path, meaning if there were to be any delays which affected the start date of this activity then there would be a delay in the entire project. In contrary to this the system hard/software test was determined to be a significant milestone because it had so many activities reliant on its successful completion.
Four other activities could not start until the system hard/software tests were completed. Similarly to integration first phase, the system hard/software tests also fall on the critical path, thus if there any delays on this activity it will delay the overall project and delay the start of other activities. Whilst creating the network schedule for the conveyer belt project we have been able to produce two useful graphical representation of the project schedule. Both a gant chart and a network diagram have been included in the report.
Both are extremely useful tools to visualise how the project and its activities are scheduled but both are also inherently different. The Gantt chart is more useful in representing the timing of various tasks which are required to successfully complete the project where as the network diagram is more useful in identifying the various tasks of the project and ordering them in their chronological order. Both charts have their own advantages and disadvantages respectively. Below in Table 1 is a summary of both network schedules advantages and disadvantages.