Гричин С.В., Ульянова О.В. - Английский язык для инженеров сварочного производства, страница 8

узкое кольцо (зазор и т. п.)сварочная горелка (для автоматической сварки –головка)основной металлзерноосаждениеостаточное напряжение435Find the English equivalents for the following words and wordcombinations.Pасплавленный металл, необходимый размер, не нагретый металл,механическиесвойства,максимумтемпературы,защищатьповерхности,быстроеохлаждение,осуществлятьконтроль,препятствовать окислению, вступать в химическую реакцию,термообработка, бомбардировка электронами, зона термического[теплового] воздействия, общая потребляемая энергия.6Complete the following sentences.1.

A characteristic feature of fusion welding is:a) molten metalb) low-voltage dischargec) inert atmosphere2. Furnace heating is usually employed ina) friction joining b) diffusion bondingc) ultrasonic joining3. The consumable electrode is madea) negative b) positive c) neither4. Total energy input in all welding processes isa) is greater than required to produce a jointb) is smaller than requiredto produce a joint c) equals to required to produce a joint5. Reactions of most metals with the atmosphere or other nearby metals can1) improve the properties of a welded joint b) make the properties of awelded joint worsec) never influence the properties of a welded joint6.

The most common gas used in gas-shielded metal-arc and gas-shieldedtungsten-arc welding isa) argonb) oxygen c) carbon dioxide7. If not controlled, residual stress results ina) precipitation processes in welded structures,b) freezing of the weldmetal c) bowing or distortion of the weldment.7Say if the following sentences are true or false.1. There is always a welding pool in solid-phase welding processes.2. Total energy input in all welding processes is greater than needed toproduce a weld.3. Reactions of metals with the atmosphere or other nearby metals arefavorable to the properties of a welded joint.4. Fluxes and inert atmospheres play a protective role and prevent oxidation.5. The heat-affected zone is a region with unaltered properties.6.

Residual stress is present in all welded structures.44Writing8Write a short report on the subject below.Function of Fluxes and Inert Atmosphere in WeldingReading and speaking9Study the Master Chart of the Principal Welding Processes (Chart1) and complete the sentences.1. The two basic welding processes are ... .2. The fusion processes consist of … .3.

Among these, arc welding can be accomplished …4. Arc welding with consumable electrodes includes the following types… .5. Carbon arc welding, atomic hydrogen welding, inert gas tungsten arcwelding refer to … .10Describe the classification of pressure processes. Use the verbs in boldfrom the previous exercise.4546Reading 211You will read the text Alternative Types of Welding.

Before you readsuggest your answers to the following questions.1. What is the difference between the principle (“traditional”) and alternativetypes of welding?2. Why are traditional welding processes not sufficient?12Match welding types (1-6) with their description (A-F). Then read thetext and check your answers.1. Cold welding2. Friction welding3. Laser welding4.

Diffusion bonding5. Ultrasonic welding6. Explosive weldingA. Light energy is used to weld parts together.B. The weld is formed at the expense of the appliedpressure at a high temperature for a long period oftime.C. Vibration is used to generate heat necessary toproduce a weld. eD. The heat to accomplish the joint is generated byrotation.E. The most important factor to accomplish the weldis pressure. No heat is applied.F. Rapid plastic deformation of the welded materialsis caused by detonation.Alternative Types of WeldingCold weldingCold welding, the joining of materials without the use of heat, can beaccomplished simply by pressing them together.

Surfaces have to be wellprepared, and pressure sufficient to produce 35 to 90 percent deformation atthe joint is necessary, depending on the material. Lapped joints in sheets andcold-butt welding of wires constitute the major applications of thistechnique. Pressure can be applied by punch presses, rolling stands, orpneumatic tooling.

Pressures of 1,400,000 to 2,800,000 kilopascals (200,000to 400,000 pounds per square inch) are needed to produce a joint inaluminum; almost all other metals need higher pressures.47Friction weldingIn friction welding two work pieces are brought together under loadwith one part rapidly revolving. Frictional heat is developed at the interfaceuntil the material becomes plastic, at which time the rotation is stopped andthe load is increased to consolidate the joint. A strong joint results with theplastic deformation, and in this sense the process may be considered avariation of pressure welding.

The process is self-regulating, for, as thetemperature at the joint rises, the friction coefficient is reduced andoverheating cannot occur. The machines are almost like lathes in appearance.Speed, force, and time are the main variables. The process has beenautomated for the production of axle casings in the automotive industry.Laser weldingLaser welding is accomplished when the light energy emitted from alaser source focused upon a work-piece to fuse materials together. Thelimited availability of lasers of sufficient power for most welding purposeshas so far restricted its use in this area. Another difficulty is that the speedand the thickness that can be welded are controlled not so much by power butby the thermal conductivity of the metals and by the avoidance of metalvaporization at the surface.

Particular applications of the process with verythin materials up to 0.5 mm (0.02 inch) have, however, been very successful.The process is useful in the joining of miniaturized electrical circuitry.Diffusion bondingThis type of bonding relies on the effect of applied pressure at anelevated temperature for an appreciable period of time. Generally, thepressure applied must be less than that necessary to cause 5 percentdeformation so that the process can be applied to finished machine parts. Theprocess has been used most extensively in the aerospace industries for joiningmaterials and shapes that otherwise could not be made—for example,multiple-finned channels and honeycomb construction. Steel can bediffusion bonded at above 1,000 ° C (1,800 ° F) in a few minutes.Ultrasonic weldingUltrasonic joining is achieved by clamping the two pieces to be weldedbetween an anvil and a vibrating probe or sonotrode.

The vibration raises thetemperature at the interface and produces the weld. The main variables arethe clamping force, power input, and welding time. A weld can be made in0.005 second on thin wires and up to 1 second with material 1.3 mm (0.05inch) thick. Spot welds and continuous seam welds are made with good48reliability. Applications include extensive use on lead bonding to integratedcircuitry, transistor canning, and aluminum can bodies.Explosive weldingExplosive welding takes place when two plates are impacted togetherunder an explosive force at high velocity. The lower plate is laid on a firmsurface, such as a heavier steel plate. The upper plate is placed carefully at anangle of approximately 5° to the lower plate with a sheet of explosivematerial on top.

The charge is detonated from the hinge of the two plates, anda weld takes place in microseconds by very rapid plastic deformation of thematerial at the interface. A completed weld has the appearance of waves atthe joint caused by a jetting action of metal between the plates.Vocabularycold weldinglapped jointsdiffusion bondingultrasonic weldingexplosive weldingbuttanvilhoneycombfinfinishedintegrated circuitrypneumatic toolingpunch presses13холодная сварка (в вакууме)соединение внахлесткудиффузное соединениеультразвуковая сваркасварка взрывомстыкнаковальняпористыйребро, пластинаготовый, обработанныйинтегральная схемотехникапневматический инструментпресс-штампFill in the blanks with the right words (namely, types of welding).1. …welding is successfully used in manufacture of small elements ofelectric circuits.2.

Heat is not used in … welding.3. … is widely used in aerospace industries.4. Vibration is used in …welding.5. Plastic deformation is the basic principle in … welding.6. … welding is impossible without pressure and high temperature.7. In … welding one of the parts being welded revolves.4914Translate the following sentences into Russian.1.При холодной сварке поверхности должны быть тщательноподготовлены.2. Скорость и толщина свариваемых деталей зависит не столько отмощности лазера, сколько от теплопроводности металла.3. Этот вид сварки наиболее широко используется в авиакосмическойпромышленности.4. Холодная сварка – это сварка без использования тепловой энергии,когда две свариваемые поверхности, обладающие высокойпластичностью, с силой прижимают друг к другу.5.

Использование точечной и шовной сварки позволяет получатьсварные соединения высокой прочности.6. Основными переменными величинами при этом виде сварки являетсяподводимое тепло, время сварки и сила сжатия.7. Фрикционным разогревом добиваются пластичности материала,затем вращение цапфы останавливают и увеличивают давление дляобеспечения сваривания поверхностей.8. Сварной шов имеет чешуйчатый вид, что является результатомобдува струей сжатого воздуха.Speaking15Choose an alternative welding method for the following applications.Explain your choice.ØØØØto join some electrical wires to form a circuita transistor canparts of a plane which have honeycomb constructionto join two aluminum sheets laid one onto anotherRevision16In each line of words (1-4) find the odd one out.

Explain your choice.1234low-voltage, gas flame, direct current, dischargegas welding, arc welding, … termit welding, resistance weldingfriction, torch, flux, filler materialfusion, filler, heat-affected, unaffected50PART 4. ARC AND GAS WELDING IN DETAILLead-in1Remember the definition and description of arc welding from theprevious part. What, in your opinion, makes arc welding one of the two mainwelding processes so widely applied in modern industry?Reading 12Study the ways of compression of information in Appendix 3.

ReadRussian texts(A-D) below and say what type of compression they are.AВ тексте описываются 2 основных метода сварки неплавящимсяэлектродом: дуговая сварка вольфрамовым электродом в защитном газе,отличающаяся стабильностью дуги и, таким образом, обеспечивающаявозможность сварки тонких листов металла, и плазменная сварка, болеескоростная и применяющаяся для сварки материалов большей толщины.Приводятся типичные сферы применения данных разновидностейсварки.BВ тексте описывается возможное вредное влияние сварки наздоровье человека. Отмечается, что снижение влияния вредныхфакторов при сварке достигается благодаря применению специальнойэкипировки и других средств защиты. Особое внимание уделяетсяпредотвращению вредного воздействия на человеческий организмвыделяемых газов. Отмечается высокий риск возникновения пожаравследствие использования легковоспламеняющихся материалов икислорода.CВ тексте приводятся сведения о применяемых в электродуговойсварке различных видaх электропитания.