What is a main pipe for pipelines?

In devices that operate in parallel, two or more in number (such as boilers in power plants), the branch pipes of each device are combined into one main pipe; this main pipe is referred to as a header (such as a steam header or a feedwater header).

It is the main pipeline for the materials, with other pipelines branching off from it. When this pipeline is cut off, all other branch pipes also lose supply.

The main pipe is the primary pipeline, corresponding to the branch pipes. For example, in factory design, to facilitate chemical addition and ensure water quality, there is usually only one centralized water supply point, even though there are multiple water usage points within the factory. At this stage, a main pipe is first designed, following a simple and straight route that passes near each water usage point; at locations close to each such point, thinner branch pipes are drawn off from the main pipe and connected near those points. Each water usage point is connected in parallel to the main pipe. The advantage of doing this is that it facilitates pipeline planning, saves on piping materials, and reduces pressure losses in the pipelines. It is possible to cut off all water supply points on the main pipe, as well as to cut off a single water supply point on a branch pipe.

Main pipeline, a term commonly used in steam pipelines