Lubricating oils
At one time the suitability of petroleum fractions for use as lubricants depended entirely on the crude oils from which they were derived. Those from Pennsylvania crude, which were largely paraffinic in nature, were recognized as having superior properties. But, with the advent of solvent extraction and hydrocracking, the choice of raw materials has been considerably extended. Viscosity is the basic property by which lubricating oils are classified. The requirements vary from very thin oil needed for the high-speed spindles of textile machinery to the viscous, tacky materials applied to open gears or wire ropes. Between these extremes is a wide range of products with special characteristics. Automotive oils represent the largest segment in the market. In the US, specifications for these products are defined by the Society of Automotive Engineers (SAE), which issues viscosity ratings with numbers that range from 5 to 50. In the United Kingdom, standards are set by the Institute of Petroleum, which conducts tests that are virtually identical to those of the SAE. When ordinary mineral oils having satisfactory lubricity at low temperatures are used over an extended temperature range, excessive thinning occurs, and the lubricating properties are found to be inadequate at higher temperatures. To correct this, multigrade oils have been developed using long-chain polymers. Such an oil performs well under cold starting conditions in winter (hence the W designation) yet will lubricate under high-temperature running conditions in the summer as well. Other additives that improve the performance of lubricating oils are antioxidants and detergents, which maintain engine cleanliness and keep fine carbon particles suspended in the circulating oil. Gear oils and greases In gear lubrication the oil separates metal surfaces, reducing friction and wear. Extreme pressures develop in some gears, notably those in the rear axles of cars, and special additives must be employed to prevent the seizing of the metal surfaces. These oils contain sulfur compounds that form a resistant film on the surfaces, preventing actual metal-to-metal contact. Greases are lubricating oils to which thickening agents are added. Soaps of aluminum, Calcium, lithium, and sodium are commonly used, while non-soap thickeners such as carbon, silica, and polyethylene also are employed for special purposes. Other petroleum products Highly purified naphthas are used for solvents in paints, cosmetics, commercial dry cleaning, and industrial product manufacture. Petroleum waxes are employed in paper manufacture and foodstuffs. Asphaltic bitumen is widely used for the construction of roads and airfields. Specialized applications of bitumen also include the manufacture of roofing felts, waterproof papers, pipeline coatings, and electrical insulation. Carbon black is manufactured by decomposing liquid hydrocarbon fractions. It is compounded with rubber in tire manufacture and is a constituent of printing inks and lacquers. Exercise 37. Match there words with their definitions 1. kerosene – a. the white, grey or black gas that is produced by burning something 2. residue – b. a thick substance made of oils or fats, used for making things such as candles for polishing things 3. friction – c. in natural condition 4. wear – d. a type of oil that is burned for heat and light 5. odour – e. a very small piece of something 6. power plant – f. damage caused when something is used over a long period 7. crude – g. a thick oily substance that is put on the moving parts of something to make it run smoothly 8. fuel – h. a substance that remains after something else has disappeared or being removed 9. grease – i. equipment in a car or other vehicle that turns power from the engine into movement 10. particle – j. a substance which can be burned to produce heat or power 11. gear – k. a liquid or power containing soap, used for washing clothes, machines 12. smoke – l. when one surface rubs against another 13. wax – m. a smell, especially an unpleasant one 14. detergent – n. a building where electricity is made Exercise 38. Fill in the gaps using the list of words or word combinations below.
1.... is still used throughout the world in cooking and space heating and is the fuel for modern.... 2.... must burn cleanly and remain fluid and free from... particles at the low temperatures. 3. The principal end use of gas oil is as... for powering automobile, truck, bus, and railway engines. 4. Furnace oil consists of... from crude oil refining. 5. In order to reduce air pollution, most industrialized countries restrict the... content of fuel oils. 6.... is the basic property by which lubricating oils are classified. 7. Other additives that improve the performance of lubricating oils are... and detergents. 8. In gear... the oil separates metal surfaces, reducing... and wear. 9.... are lubricating oils to which thickening agents are added.
Exercise 39. Complete the following sentences. 1. Kerosene is still used extensively throughout the world in.... 2. When burned as a domestic fuel, kerosene must produce a flame free of.... 3. The principal end use of gas oil is as diesel fuel for powering.... 4. Furnace oil consists largely of.... 5. Residual fuels may contain large quantities of.... 6. Viscosity is the basic property by which.... 7. Greases are lubricating oils to which.... 8. In gear lubrication the oil separates....
Exercise 40. Decide whether the following statements are true (T) or false (F) in relation to the information in the text. If you think a statement is false, change it to make it true. 1. __Kerosene is still used extensively as an illuminant. 2. __All kerosene fuels must satisfy minimum flash point specifications (49° C) to limit fire hazard in storage and handling 3. __ Furnace oil consists mainly of residues from crude oil refining. 4. __ Fuel oils are used for powering automobile, truck, bus and railway engines. 5. __ In order to reduce air pollution, many countries reduce the sulfur content of fuel oils. 6. __Nowadays the suitability of petroleum fractions for use as lubricants depends on the crude oils from which they are derived. 7 __ Gear oils separate metal surfaces and reduce friction and wear.
Exercise 41. Answer the following questions. 1. How is kerosene used nowadays? 2. Kerosene must produce a flame free of smoke and odour, must not it? 3. What characteristics must jet fuel have? 4. What is the principal end use of gas oil? 5. What is the best diesel fuel made of? 6. What engines can tolerate even heavy diesel oils? 7. Why are the more viscous marine diesel oils heated? 8. What can you tell about the standards for diesel fuel quality? 9. Does furnace oil consist of residues from crude oil refining? 10. What may residual fuels contain? 11. What is done to reduce air pollution? 12. How do requirements for viscosity vary? 13. What can you tell about automotive oils? 14. How do lubricating properties depend on temperature? 15. What quality of lubricating oils maintains engine cleanliness? 16. What are greases? Exercise 42. Circle the correct verb form to fill in the gaps in the sentences. 1. Standard laboratory procedures... these properties by burning the oil in special lamps. a) tests b) test c) are testing 2. Detonation... to harmful knocking in a gasoline engine. a) leads b) is leading c) lead 3. Oils... to permit easy pumping. a) heat b) are heated c) is heated 4. Most industrialized countries now... the sulfur content of fuel oils. a) is restricting b) restricted c) restrict
Exercise 43. Rewrite the following sentences in Passive Voice. 1. Straight-chain hydrocarbons make the best diesel fuel. 2. We use kerosene extensively throughout the world in cooking and space heating. 3. We heat the more viscous marine diesel oils to permit easy pumping. 4. Industrialized countries restrict the sulfur content of fuel oils. 5. The Society of Automotive Engineers defined specifications for automobile oils. 6. In gear lubrication the oil separates metal surfaces. 7. We employ non-soap thickeners for special purposes.
Exercise 44. Indicate the suffixes in the following nouns. Write down the verbs from which they are formed and translate them. The first one has been done for you. Model: pollu tion (забруднення) – to pollute (забруднювати) Lubrication, lubricant, requirement, contaminant, performance, location, compression, combustion. Exercise 45. Form the plural from of the following nouns. Property, procedure, fuel, particle, country, oil, condition, surface, grease, purpose, thickener.
Exercise 46. Put special questions to the underlined words. 1. Kerosene is used in cooking and space heating. 2. In gears lubrication the oil separates metal surfaces. 3. Residual fuels may contain large quantities of heavy metals. 4. Kerosene must produce a flame free of smoke and odour. 5. Automotive oils represent the largest segment in the market.
Exercise 47. Choose the correct word to complete each sentence. Define their part of speech. You can change the words slightly. lubrication – lubricant – lubricating – lubricate 1. Such an oil... under high-temperature running conditions in the summer. 2. Earlier the suitability of petroleum fractions for use as... depended entirely on the crude oil. 3. Greases are... oils to which thickening agents are added. 4. The purpose of engine... is to prevent metal-to-metal contact between parts. viscous – viscosity 1.... is the basic property by which lubricating oils are classified. 2. More marine diesel oils are heated to permit easy pumping and to give the correct... at the fuel injectors for good combustion. contaminant – contamination – to contaminate 1. Chemical waste had... the water supply. 2. Such... are not easily removed and usually lead to lower market prices for fuel oils. 3. In order to reduce... many countries restrict the sulfur content of fuel oils.
Exercise 48. Look back in the text and find words that have a similar meaning to: up-to-date (adj.) smell (n) danger (n) contamination (n) to divide (v) to lower (v) remainder (n) Exercise 49. Use the information in the text to complete the dialogue in your own words. A: What oil products do you know? B:.... A: Where is kerosene used nowadays? B:.... A: What are the main characteristics of kerosene? B:.... A:...? B: Diesel fuel is used for powering automobile, truck, bus and railway engines. A:...? B: It starts to burn at several locations within the cylinder after the fuel is injected. A: What is the purpose of oil in gear lubrication? B:.... A:...? B: These oils contain sulfur compounds. A:...? B: Greases are lubricating oils to which thickening agents are added.
Exercise 50. Translate into English. 1. Гас все ще широко використовується при приготуванні їжі, і є основним паливом для сучасних реактивних двигунів. 2. Реактивні палива повинні згоряти чисто і залишати рідину без часточок воску при низьких температурах. 3. Військові реактивні палива спеціального призначення мають навіть більше суворих вимог. 4. Паливне масло складається з великої кількості залишків від очищення нафти.
Exercise 51. Translate the text in a written form and put 5 questions to it.
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