The Critical Path – Precedence diagram method
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Transcript of The Critical Path – Precedence diagram method
The Critical Path – Precedence diagram method
Luise LorenzChristina Mohr
Critical Path Method (CPM)Project planning techniqueImportant tool for project
managementFor any project with
interdependent activities
CPM helps you figure out:
how long a complex project will take to complete
which activities are critical◦those needed to be done in time in
order to follow the schedule
The model of CPM1. A list of all activities required to
complete a project
2. The duration of each activity has to be known
3. Analyze the dependencies between the activities
The model of CPMCPM calculates the longest path of
planned activities to the endEarliest and latest date that each
activity can start and finishAvoiding extension of the projectDetermining the ‚critical‘ activitiesActivities which have ‚total float‘
(delayed without making the project longer)
Critical pathSeries of project network activities
which lead to the longest overall duration
Shortest time to complete a projectDelay of critical activity has an impact
on the completion dateShorten the planned critical path by
‚fast tracking‘ (more activities parallel) or ‚crashing the critical path‘ (shortening activities by adding resources)
Precendence diagram method (PDM)
Network diagram uses boxes to represent activities
Connection with arrows to show the dependencies
Early / late start dateEarly / late finish dateDuration
Advantages of PDMFinding the critical pathDefining the amount of time
requiredUsage to crash projectsTo reduce resourcesDefining dependenciesIdentifying lead and lag times
Design I
Operation Description
ES(Earliest Start)
EF(Earliest Finish)
Float
LF(Latest Finish)
LS(Latest Start)
Ref. No.Duration
if the float equals zero it‘s
considered critical
Design II
ES
LF
EF
LS Float
Duration
Operation Description
if the float equals zero it‘s
considered critical
Example
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