The centers of holes, weld plugs, and round parts are shown on prints using ______ lines

The centers of holes, weld plugs, and round parts are shown on prints using center lines. These lines are specifically designed to indicate the location of the center of circular or symmetrical features, which is crucial for accurately positioning and aligning components in manufacturing and fabrication processes.

Center lines are typically represented as alternating long and short dashed lines, which distinguishes them from other types of lines, such as hidden or dimension lines. Their unique style helps prevent confusion regarding the feature they indicate and clearly shows the center of the object for further dimensions or to demonstrate symmetry. This clarity is essential for proper machining, welding, and assembly of components.