Process Flow chart symbols
In a Process flow chart symbols represent different items in a process or operation. There are many variants to the symbols and specific symbols can be included in some charts to specify special steps in certain processes. The general symbol shapes for a process flow diagram are the following:
Square: This symbolizes a process step where there is actual work being done, or value add activities to raw materials or work in progress. Process steps should be split up into taks and not be too general as there is the possibility of missing important sub steps or waiting/idle times which are a form of waste.
Inverted triangle: This sybolizes an inventory hold, warehouse or work in progress inventory bin/warehouse. This is where material accumulates before being put through the next process step. It is important to identify these stores as they contribute to working capital requirements, inventory costs and can highlight other problems in the system.
Square with one rounded side: This symbol represents a delay in the system, downtime or waiting period where items have to wait on a process to finish or a certain waiting period required as part of the process. These waiting periods must be carefully measured and recorded.
Diamond: This symbol represents a decision point in the process, where there is a check, outcome or decision that has to be made like a quality check.
Arrow: An arrow indicates process, material or work in progress flow through the process.
The symbols most commonly used to construct a process flow chart can be seen below:
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