What term is used for the lowest interior point within a pipe?

The term used for the lowest interior point within a pipe is "Invert." In the context of piping and drainage systems, the invert refers to the bottom inside surface of the pipe. It is a critical reference point for various calculations, such as determining flow rates and assessing the proper slope for drainage. When engineers and maintenance personnel evaluate a pipeline system, understanding the location of the invert is essential for ensuring effective wastewater flow and preventing issues such as blockages or backup.

The other terms, while related to pipe design, refer to different components or features. For example, the crown denotes the highest point of the inner wall of the pipe, and the springline is the point on the pipe at which the curve of the arch begins. The operating range pertains to the functional capacity or limits of equipment rather than a physical measurement within the pipe itself.