Critical Path Method

This section is devoted to using critical path method (CPM) as a tool for the scheduling and sequencing of work for shutdowns and project work. 

Source Martino, R.L. Plain Talk on Critical Path Method, Chemical Engineering, June 10,1963,... 

Zalokar, F.J. The Critical Path Method-A Presentation and Evaluation, monograph published by General Electric Co., Schenectady, May 18,1964. 

Acronym for Critical Path Method. A network diagramming technique that places emphasis on time, cost, and the completion of events. 

When we undertake to develop a new coal mine, it is common practice to set up a Critical Path Method of controlling the construction during the five to eight years of the development period. Since the number of "activities" amounts to from 500 to 1,000, it is necessary to set the program up on a computer and update it monthly. 

I believe that we now need to expand the Critical Path Method of analysis to cover all the items which are directly and indirectly involved in the expansion of the coal industry to the 1 billion tons per year level. These include the usual ones such as capital, manpower, equipment, and, in addition, the environmental, legislative, political and social items. The latter have become as important as the other more common items. 

When the times for each project task are very firm a special method, the Critical Path Method (CPM), can be used to ask more sophisticated questions about how to shorten the project time. The types of questions that can be asked are what are the benefits to the completion date by adding more manpower to task A or more capital into task B ... 

PERT (Performance Evaluation Review, and Tracking) and CPM (Critical Path Method) charts (flowcharts) show the flow, connectivity, and interdependency of project tasks, activities, and goals. A PERT chart (Figure 27.9) depicts the activities in the order that they will need to be carried out, either in series or in parallel. These charts also identify which activities need to be completed (or initiated) before the next activity, which is dependent on it, can be initiated. 

Credits in bookkeeping, 143-144 Criminal liability, 263 Critical path method (CPM), 18, 407-408 Crushing and grinding equipment, cost of, 562-566... 

Although project management was certainly applied in practice prior to the mid-1950 s, the development of the critical path method and the Project Evaluation and Review Technique (PERT) is considered to be the initiation of the modern practice of project management. The critical path method is a network analysis technique used to predict project duration by analyzing which sequence of activities or path most likely has the least amount of scheduling flexibility or... 

Action systems will tighten up as time compresses. Project management systems such as the Critical Path Method and the Program Evaluation and Review Technique, so successfully used in the Sixties, will find wider application. 

In order to ensure a high grade of expression of the plans, time relations as proposed by Allen (1991) have been used for the phase of plan definition. Logical and time-connected relations between tasks to be planned have to be described within the plan definition phase. Based on 13 Allen time relations, the results of each task are described dependent on the relations to other tasks. Therewith all necessary constraints between related tasks can be represented. This is why TOPP differs from critical path methods. This method only uses the start and the finish to describe time relations. 

Network analysis can be used to describe the complicated precedence relationships between the activities of a large project. The resulting description can be used to determine a timetable for the activities and to predict a completion date for the project. Examples of network planning methods (or project planning methods) are the Critical Path Methods (CPM) and Performance Evaluation and Review Technique (PERT) (Chryssolouris 2006). 

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