The petroleum industry faces problems in transportation of crude petroleum be-cause of the deposition of paraffins, hydrates and asphaltenes on the insides of thepipeline. These are conventionally removed using either chemical inhibitors or mechani-cal devices, called pigs, which travel through the pipeline and mechanically scrape awaythe deposits. These pigs are propelled by the pipeline product itself and hence travel atthe same velocity as the product. Research has indicated that cleaning would be betterif the pigs are traveling at a relatively constant velocity of around 70% of the productvelocity.This research utilizes the concept of regulating the bypass flow velocity in order tomaintain the pig velocity. The bypass flow is regulated by the control unit based onthe feedback from the turbine flowmeter, which monitors the bypass flow. A motorizedbutterfly valve is used for actually controlling the bypass flow.In addition to cleaning, the proposed pig utilizes on-board electronics like accelerom-eter and pressure transducers to store the data gathered during the pig run. This datacan then be analyzed and the condition of the pipeline predicted.Thus, this research addresses the problem of designing a pig to maintain a constantvelocity in order to achieve better cleaning. It also helps gather elementary data thatcan be used to predict the internal conditions in the pipe.
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