Editing Pipeline (section)

==Technology==

===Components===
[[File:Trans-Alaska Pipeline crossing a ridge by Tanana River.jpg|thumb|right|The Trans Alaska Pipeline crossing under the [[Delta River]] and over ridge of the [[Alaska Range]]]]

Pipeline networks are composed of several pieces of equipment that operate together to move products from location to location. The main elements of a pipeline system are:

;Initial injection station: Known also as "supply" or "inlet" station, is the beginning of the system, where the product is injected into the line. Storage facilities, pumps or compressors are usually located at these locations.

;Compressor/pump stations: [[Pump]]s for liquid pipelines and [[compressors]] for gas pipelines, are located along the line to move the product through the pipeline. The location of these stations is defined by the topography of the terrain, the type of product being transported, or operational conditions of the network.

;Partial delivery station: Known also as "intermediate stations", these facilities allow the pipeline operator to deliver part of the product being transported.

;Block valve station: These are the first line of protection for pipelines. With these valves the operator can isolate any segment of the line for maintenance work or isolate a rupture or leak. Block valve stations are usually located every 20 to {{convert|30|mi|km}}, depending on the type of pipeline. Even though it is not a design rule, it is a very usual practice in liquid pipelines. The location of these stations depends exclusively on the nature of the product being transported, the trajectory of the pipeline and/or the operational conditions of the line.

;Regulator station: This is a special type of valve station, where the operator can release some of the pressure from the line. Regulators are usually located at the downhill side of a peak.

;Final delivery station: Known also as "outlet" stations or terminals, this is where the product will be distributed to the consumer. It could be a tank terminal for liquid pipelines or a connection to a distribution network for gas pipelines.

===Leak detection systems===
Since oil and gas pipelines are an important asset of the economic development of almost any country, it has been required either by government regulations or internal policies to ensure the safety of the assets, and the population and environment where these pipelines run.

Pipeline companies face government regulation, environmental constraints and social situations. Government regulations may define minimum staff to run the operation, operator training requirements, pipeline facilities, technology and applications required to ensure operational safety. For example, in the State of Washington it is mandatory for pipeline operators to be able to detect and locate leaks of 8 percent of maximum flow within fifteen minutes or less. Social factors also affect the operation of pipelines. Product theft is sometimes also a problem for pipeline companies. In this case, the detection levels should be under two percent of maximum flow, with a high expectation for location accuracy.

Various technologies and strategies have been implemented for monitoring pipelines, from physically walking the lines to satellite surveillance. The most common technology to protect pipelines from occasional leaks is Computational Pipeline Monitoring or CPM. CPM takes information from the field related to pressures, flows, and temperatures to estimate the hydraulic behavior of the product being transported. Once the estimation is completed, the results are compared to other field references to detect the presence of an anomaly or unexpected situation, which may be related to a leak.

The [[American Petroleum Institute]] has published several articles related to the performance of CPM in liquids pipelines. The API Publications are:
*RAM 1130 – Computational pipeline monitoring for liquids pipelines
*API 1149 – Pipeline variable uncertainties & their effects on leak detectability

Where a pipeline containing passes under a road or railway, it is usually enclosed in a protective casing. This casing is vented to the atmosphere to prevent the build-up of flammable gases or corrosive substances, and to allow the air inside the casing to be sampled to detect leaks. The ''casing vent'', a pipe protruding from the ground, often doubles as a warning marker called a ''casing vent marker''.<ref>''[https://corenaturalresources.com/redirect Pipeline Safety] {{Webarchive|url=https://web.archive.org/web/20150518101537/http://www.consolenergy.com/natural-gas-amp-coal/natural-gas/pipeline-safety.aspx |date=2015-05-18 }}'', CONSOL Energy, accessed 2015-05-13</ref>