http://en.wikipedia.org/wiki/Pigging#Intelligent_pigging
Pigging in the maintenance of pipelines refers to the practice of using pipeline inspection gauges or 'pigs' to perform various operations on a pipeline without stopping the flow of the product in the pipeline. These operations include but are not limited to cleaning and inspecting of the pipeline.
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Intelligent pigging
Modern intelligent pigs are highly sophisticated instruments that vary in technology and complexity by the intended use and by manufacturer. An intelligent pig, or smart pig, is basically a computer that collects various forms of data during the trip through the pipeline.
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Etymology
Pigs get their name from the squealing sound they make while traveling through a pipeline.[1] (Disputed: 'PIG' is an acronym or backronym derived from the initial letters of the term 'Pipeline Inspection Gauge' or possibly 'Pipeline Inspection Gizmo' or 'Pipeline Internal Geometry' or 'Pipeline Inspection Gadget')

http://www.srbijagas.com/?q=vesti/17_02_2010/generalno_obave...
Konsultantske usluge: Analiza inteligentnog kracovanja radi analize i preporuka za vršenje radova na održavanju gasovoda i opremljenosti sistema u pogledu sigurnosti; Podrška Jedinici za sprovođenje projekta uključujući nabavku; Bazni projekat za objekat podzemnog skladišta gasa; studija izvodljivosti za skladište/projekat/pripremu tenderske dokumentacije; studija izvodljivosti za interkonekciju; Analiza strateškog planiranja razvoja Srbijagasa; i Tehnički monitoring zajmodavca

Consultancy services: PIG survey fitness for purpose study; PIU support including procurement; Basic design for the underground gas storage facility; feasibility study for storage/design/preparation of tender documents; feasibility study for interconnection; Integrated Strategic Expansion plan study for Srbjiagas; and a Lenders Technical Monitor

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Note added at 3 hrs (2010-11-26 12:20:50 GMT)
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http://www.energogas.net/usluge/Komercijalni katalog GasTeh....
Tip 318: Kuglasta slavina čistačka
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pig valve

http://www.girardind.com/products.cfm?cat=3
The Argus Pig Valve is considered one of the best pigging valves available utilized extensively on oil pipelines and gas flow pipelines around the world. This is an excellent alternative to the conventional pigging method and provides safe, operator friendly pig launching and receiving.

http://www.rgf.bg.ac.rs/predmet/RO/VII semestar/Eksploatacij...
Pražnjenje i čišćenje cevovoda
- u kutiju se postavi odgovarajući čistač (kracer) i pomoćnim alatom se gurne napred mimo priključka 6 i prve rasteretne slavine;
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Molim vas pogledajte sliku 5.28
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Osetljivost sistema kracovanja je naročito zbog toga što se izvodi u pogonskim uslovima, a da se komfor krajnjih korisnika ne poremeti. O kracovanju se obaveštavaju krajnji korisnici zbog pripravnosti za eventualni nenamerni zastoj u isporuci.