In engineering drawings, what does a 'center line' represent?

A center line in engineering drawings primarily serves as a guide that indicates symmetry. It helps identify the middle point of a component or system, which is essential for ensuring that parts are symmetrical and aligned correctly during manufacturing and assembly processes. This representation is crucial for parts that require balance or symmetrical features, such as circular components, where the center line runs through the axis of symmetry. By establishing symmetry, the center line aids in the precise placement and fitting of components, thereby maintaining the integrity of the design.

In engineering practice, while other lines like hidden lines indicate features not visible in the current view and guideline lines assist in assembly placements, the center line distinctly emphasizes the aspect of symmetry. Artistic renditions, on the other hand, are typically not represented by center lines as they focus more on aesthetics than functional engineering principles. Thus, the representation of a center line as a means of indicating symmetry is essential in creating effective and accurate engineering drawings.