Definition - What does Trunk Line mean?
A Trunk Line is a pipeline which is used to transport crude oil and natural gas across countries or within states. These pipelines are the set of large diameter carbon steel pipelines which carry the petroleum products across countries or borders. Trunk Pipelines are broadly classified into two types:
- Interstate Pipelines – These trunk lines transfer petroleum (Crude oil, Natural gas and Products) across country borders. They also called Cross country pipelines.
- Intrastate Pipelines - These trunk lines transfer petroleum (Crude oil, Natural gas and Products) across various states in a country.
Petropedia explains Trunk Line
Pipelines are one of the safest and most effective way of transporting crude oil, natural gas and petroleum products between border sharing nations and states. The industry jargon for pipelines vary with respect to the oil and gas sectors viz upstream, midstream and downstream.
In the upstream side of oil and gas industry, the pipelines which carry crude oil and natural gas from the wellhead to the processing plants are called gathering systems. These are small diameter pipelines. Once crude oil and natural gas are processed and impurities are removed, they are sent to trade in the market of the countries or states which need them via trunk pipelines (intrastate as well as interstate pipelines). The crude oil is transported to the respective countries or the state refineries for further processing via large diameter trunk pipelines. Once the Petroleum products are produced, they are further transported to various demand centers within the country either by intrastate pipelines, rail or road network. To carry the products further to the customers, small diameter pipelines called spur lines are connected to the trunk lines which carry the products further to the densely populated demographic regions.
The trunk pipelines are large diameter carbon steel pipelines with diameters ranging from 20 inches to 48 inches or more and cover more than 2000 km distances.
The diagram below represents the flow of hydrocarbons from upstream to midstream to downstream and the notations of pipelines.