What Does Invert Mean?
An invert refers to the lowest point on the inner diameter of the pipe, and is located at the pipe end. It is identified by the pipe bottom elevation and plays an important role in ensuring the proper flow of fluid within the pipe system.
Inverts have to be coordinated with other components of the pipeline to ensure a consistent grade. In sewer pipes, fluid is transported under gravity, and correct slope is essential to allow proper drainage. Inadequate slope can cause deposition of solid particles on the pipe invert leading to blockages.
Trenchless rehabilitation methods such as cured-in-place pipe (CIPP), sliplining and pipe bursting can be used to rectify damaged pipes.
Trenchlesspedia Explains Invert
Depending on pipe thickness, the level of the ground below the pipe bottom may be lower than the invert. Invert level is obtained on subtracting the pipe diameter and wall thickness from the elevation at the crown or top of the pipe.
The reference for an invert level is usually a floor slab above it. Knowing the elevation of the floor slab and the ceiling height, the Invert level can be measured. Knowing the invert level also helps to determine the location of a drop manhole if required. When two sewers connect and the level difference between invert of branch sewer and water line in the main sewer at maximum discharge is more than 0.6 meter, a drop manhole is constructed.
It can have a vertical or near-vertical drop pipe from the sewer at a higher elevation to the one at a lower elevation.