Гурова Г.Г., Николаева Н.С. - Обучение разговорной речи и чтению литературы на английском языке по специальности Сварка (1058938), страница 3
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width;d)is basically a root face of zero thickness.4. A groove isa) an opening or space provided under the edges of the metal partsto be welded;b) an opening or space provided between the edges of the metalparts to be welded;c) an opening or space provided between the edges of the metal partsto be cut;d) an opening or space provided between the surface of the metalparts to be welded.5. The bevel angle is the angle formeda) between the weld reinforcement and a plane perpendicular to thesurface of the member;b) between the prepared edge of a member and a plane perpendicularto the surface of the member;c) between the prepared edge of a member and a plane parallel tothe surface of the member;d) between the prepared edge of a member and a plane perpendicularto the centre line of the root cross section.6.
What is a groove angle? It isa) the angle between the surface of the member and the plane perpendicular to the edge of it;b) the prepared edge of a member and a plane perpendicular to thesurface of the member;c) the partial angle of the groove between the parts to be joined;15d) the total angle of the groove between the parts to be joined.7. What is not necessary to consider to determine the bevel angle,groove angle and root opening for a joint?a) the type of joint to be made;b) the thickness of the weld material;c) the weld reinforcement;d) the welding process to be used.8. Weld reinforcement is a term used to describea) weld metal in excess of the metal necessary to fill a joint;b) the filler metal used to make up a weld;c) the molten metal necessary to fill a joint.1.18.
Scan the text and fill in the left part of the table using theinformation from the text. Find the information in the Internet and yourtextbooks to fill in the right part.TermDefinition in EnglishTranslationDefinition in Russian1.19. Before reading the text “Heat-affected Zone” try to answer thefollowing questions.1. What in your opinion influences the heat-affected zone?2.
What are the characteristics of the process of shielded metal arcwelding?3. What are the characteristics of the process of gas metal arc welding?4. What are the characteristics of the process of submerged arc welding?5. What are the characteristics of the process of gas tungsten arcwelding?6. How do these characteristics influence the heat-affected zone?1.20. Read the text “Heat-affected Zone” paying attention to the active terminological vocabulary to check if your predictions were correct.Heat-affected ZoneThe zone of interest for the welder is the heat-affected zone. Thiszone includes that portion of the base metal that has not been melted;16however, the structural or mechanical properties of the metal have beenaltered by the welding heat. Because the mechanical properties of thebase metal are affected by the welding heat, it is important that youlearn techniques to control the heat input.
One technique often used tominimize heat input is the intermittent weld. In the picture you can seethe HAZ of a pipe weld, with the blue area being the metal most affectedby the heat.Zones in a weld. The effects of welding on the material surroundingthe weld can be detrimental — depending on the materials used and theheat input of the welding process used, the HAZ can be of varying sizeand strength. The thermal diffusivity of the base material plays a largerole — if the diffusivity is high, the material cooling rate is high and theHAZ is relatively small. Conversely, a low diffusivity leads to slowercooling and a larger HAZ.
The amount of heat injected by the weldingprocess plays an important role as well, as processes like oxyacetylenewelding have an unconcentrated heat input and increase the size of theHAZ. Processes like laser beam welding give a highly concentrated, limited amount of heat, resulting in a small HAZ. Arc welding falls betweenthese two extremes, with the individual processes varying somewhat inheat input. To calculate the heat input for arc welding procedures, thefollowing formula can be used: V · I · 60 × Efficiency,Q=S · 1000where Q = heat input (kJ/mm), V = voltage (V), I = current (A) andS = welding speed (mm/min).
The efficiency is dependent on the welding process used, with shielded metal arc welding having a value of170.75, gas metal arc welding and submerged arc welding, 0.9, and gastungsten arc welding, 0.8.From http://en.wikipedia.org/wiki/Welding#_note-27#_note-271.21. Vocabulary to the text “Heat-affected Zone”. Try tomemorizethe following words and word combinations:1) a heat-affected zone — зона термического влияния;2) to alter [ O:lt@], v — меняться;3) heat input — ввод тепла;4) an intermittent weld — прерывистый шов;5) to surround, v — окружать;6) detrimental [ detrı ment(@)l], adj — вредный, пагубный;7) thermal diffusivity — теплопроводность, коэффициент теплопроводности;8) conversely [ konv3:slı], adv — обратно, противоположно, наоборот;9) to result in, v — привести к...;10) voltage [ vltıÃ], n — электрическое напряжение;11) current [ kr(@)nt], n — электрический ток;12) a value [ vælju:], n — значение.Word Study1.22.
Read the words correctly. Consult the dictionary if necessary.To minimize, procedure, formula, technique, to vary, diffusivity, toinject, voltage.1.23. Translate the following sentences into Russian paying attentionto the underlined words.1. One technique often used to minimize heat input is the intermittentweld. 2. The effects of welding on the material surrounding the weld canbe detrimental—depending on the materials used and the heat input of thewelding process used. 3. The welder must also carefully add filler metalat the proper times doing manual GTAW. 4. Gas tungsten arc weldingis a process used to produce high-quality welds in virtually all weldablemetals.
5. Having initiated the arc between the welding electrode andthe base metal, the welder controls correct arc length. 6. The electrodeson small spot welders, used to weld thin materials, may be air-cooled.7. The welding machine electrodes are flat plates called platens. 8. This18causes the materials being joined to vibrate at a corresponding rate. 9. Acoupling system transmits the mechanical vibration to the welding tipand thus into the metals being joined. 10.
The pressure used is lessand the welding time is shorter, than those used in resistance welding.11. Aluminum welded by the cold welding has a tensile strength of upto 152 MPa.1.24. Translate the following sentences into Russian paying attentionto the underlined words.1. In the picture you can see the HAZ of a pipe weld, with theblue area being the metal most affected by the heat. 2.
Arc weldingfalls between these two extremes, with the individual processes varyingsomewhat in heat input. 3. The efficiency is dependent on the weldingprocess used, with shielded metal arc welding having a value of 0.75.4. Double-V preparation joints are characterized by the two pieces ofmaterial, each tapering to a single centre point at one-half their height.5. This type of joint having some applications in platework, it is morefrequently used in sheet metal work. 6. The HAZ includes the portionof the base metal that has not been melted, the structural or mechanicalproperties of the metal having been altered by the welding heat.
7. Thediffusivity being high, the material cooling rate is high and the HAZ isrelatively small. 8. Many variations of joints being used, the parts ofthe joint are described by standard terms. 9. The heat of the electric arcbeing controlled by the current setting and by the arc length, electrodediameter and flux material will determine the type (ac or dc) and amountof welding current required. 10. With the tungsten electrode being notconsumed, it does not melt and enter the weld.1.25. Match the two halves of the sentence fragments to make logical statements.1.26.
Translate the following text from Russian into English.Правильная разделка кромок свариваемых деталей обеспечиваеткачественный и полный провар. В тексте были приведены наиболеечасто применяемые формы разделки кромок листов для полученияодностороннего шва. Сочетание минимального зазора между наклонными кромками свариваемых листов и угла между этими двумянаклонными кромками должно выбираться таким образом, чтобы191. The heat-affected zone includes that portion of the basemetala) it is important that you learntechniques to control the heatinput2. Because the mechanical properties of the base metal areaffected by the welding heatb) the material cooling rate ishigh and the HAZ is relativelysmall3.
One technique often used tominimize heat inputc) that has not been melted4. The HAZ can be of varyingsize and strengthd) resulting in a small HAZ5. If the diffusivity is highe) depending on the materialsused and the heat input of thewelding process used6. Processes like laser beamwelding give a highly concentrated, limited amount of heatf) with gas metal arc welding andsubmerged arc welding having avalue of 0.97.
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