Other features that an MFL tool can identify
Although primarily used to detect corrosion, MFL tools can also be used to detect features that they were not originally designed to identify. When an MFL tool encounters a geometric deformity such as a dent, wrinkle or buckle, a very distinct signal is created due to the plastic deformation of the pipe wall.
Nondestructive testing
Nondestructive testing (also called NDT, nondestructive evaluation, NDE, and nondestructive inspection, NDI) is testing that does not destroy the test object. NDE is vital for constructing and maintaining all types of components and structures. To detect different defects such as cracking and corrosion, there are different methods of testing available, such as X-ray (where cracks show up on the film) and ultrasound (where cracks show up as an echo blip on the screen). While destructive testing usually provides a more reliable assessment of the state of the test object, destruction of the test object usually makes this type of test more costly to the test object's owner than nondestructive testing. Destructive testing is also inappropriate in many circumstances, such as forensic investigation. That there is a tradeoff between the cost of the test and its reliability favors a strategy in which most test objects are inspected nondestructively; destructive testing is performed on a sampling of test objects that is drawn randomly for the purpose of characterizing the testing reliability of the nondestructive test.
| active corrosion | активная коррозия |
| bell hole | углубление в траншее трубопровод (позволяющее вести сварку по всей окружности шва двух спущенных в траншею примыкающих секций) |
| branch connection | патрубок |
| buried conditions | подземные условия |
| cathodic protection | катодная защита |
| coating | покрытие |
| corrosion pit | коррозионная язва; точечная коррозия |
| defect assessment | оценка дефекта |
| defect identification | выявление дефекта |
| delamination | расслаивание; расслоение |
| girth weld | кольцевой сварной шов |
| intelligent pig | скребок для автоматизированной чистки |
| laser profilometer | лазерный профилометр |
| magnetic flux leakage | рассеяние магнитного потока |
| operating conditions | условия эксплуатации |
| pigging | чистка трубопровода скребками |
| pinpoint | выявлть |
| pipeline inspection | технический осмотр |
| pitting corrosion | питтинг, питтинговая коррозия |
| profile gauge | резьбовое лекало |
| survey | обследование |
| thickness gauge | толщиномер |
| wall loss | потери мощности вследствие поверхностных токов |
| wall thickness | толщина стенки |
| weld | сварной шов |
| yield strength | условный предел текучести |
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Oil refinery
An oil refinery is an industrial process plant where crude oil is processed and refined into more useful petroleum products, such as gasoline, diesel fuel, asphalt base, heating oil, kerosene, and liquefied petroleum gas. Oil refineries are typically large sprawling industrial complexes with extensive piping running throughout, carrying streams of fluids between large chemical processing units.
Crude oil is separated into fractions by fractional distillation. The fractionating column is cooler at the top than at the bottom because the fractions at the top have lower boiling points than the fractions at the bottom. The heavier fractions that emerge from the bottom of the fractionating column are often broken up (cracked) to make more useful products. All of the fractions are subsequently routed to other refining units for further processing.
Raw oil or unprocessed ("crude") oil is not useful in the form it comes in out of the ground. Although "light, sweet" (low viscosity, low sulfur) oil has been used directly as a burner fuel for steam vessel propulsion, the lighter elements form explosive vapors in the fuel tanks and so it is quite dangerous, especially so in warships. For this and many other uses, the oil needs to be separated into parts and refined before use in fuels and lubricants, and before some of the byproducts could be used in petrochemical processes to form materials such as plastics, and foams. Petroleum fossil fuels are used in ship, automobile and aircraft engines. These different hydrocarbons have different boiling points, which means they can be separated by distillation. Since the lighter liquid elements are in great demand for use in internal combustion engines, a modern refinery will convert heavy hydrocarbons and lighter gaseous elements into these higher value products using complex and energy intensive processes.
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Oil can be used in so many various ways because it contains hydrocarbons of varying molecular masses, forms and lengths such as paraffins, aromatics, naphthenes (or cycloalkanes), alkenes, dienes, and alkynes. Hydrocarbons are molecules of varying length and complexity made of only hydrogen and carbon atoms. Their various structures give them their differing properties and thereby uses. The trick in the oil refinement process is separating and purifying these.
Once separated and purified of any contaminants and impurities, the fuel or lubricant can be sold without any further processing. Smaller molecules such as isobutane and propylene or butylenes can be recombined to meet specific octane requirements of fuels by processes such as alkylation or less commonly, dimerization. Octane grade of gasoline can also be improved by catalytic reforming, which strips hydrogen out of hydrocarbons to produce aromatics, which have much higher octane ratings. Intermediate products such as gasoils can even be reprocessed to break heavy, long-chained oil into a lighter short-chained one, by various forms of cracking such as Fluid Catalytic Cracking, Thermal Cracking, and Hydrocracking. The final step in gasoline production is the blending of fuels with different octane ratings, vapor pressures, and other properties to meet product specifications.
Oil refineries are large scale plants, processing from about a hundred thousand to several hundred thousand barrels of crude oil per day. Because of the high capacity, many of the units are operated continuously (as opposed to processing in batches) at steady state or approximately steady state for long periods of time (months to years).
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