What lines are utilized to determine a machine's elevation and horizontal position?

Benchmarks are critical reference points used in construction and millwright work to establish a consistent elevation and horizontal positioning for machinery. They are typically permanent markers, such as a point on a building or structure, and provide a fixed reference that can be used to ensure that all other elevations are measured relative to this point. By using benchmarks, millwrights can accurately set the height and alignment of machines, ensuring they operate effectively and efficiently.

In practice, benchmarks help mitigate cumulative errors that can occur during the leveling and setting of equipment. When a millwright establishes the position of machinery, all measurements begin from this known point, thus allowing for precise adjustments and alignments. This method is essential for ensuring that machinery operates within the intended specifications and that there is no misalignment that could lead to further operational issues.