Гричин С.В., Ульянова О.В. - Английский язык для инженеров сварочного производства (1044906), страница 19
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During heavy service, dothis monthly.Answer the following questions.1. What should be inspected daily by a welding operator to avoid electricshock?1042. What should be cleaned/ changed/ replaced while maintaining wire feeder?3. Why shouldn’t you touch the electrode wire when the welding powersource is on?4. Why shouldn’t cylinders be stored or used in a horizontal position?5. Should you try to repair a faulty regulator yourself?6. What are booths and partitions used for?7. What shouldn’t a welder store in his pockets?11Summarize the information of the text using the following incompletesentences as a plan.1.
To avoid electrical shocks a welder should/shouldn’t… (inspect, repair,etc.)2. The following things should be remembered when inspecting andmaintaining wire feeder … .3. To use and store electrodes safely, one should/shouldn’t … .4. Gas cylinders should be stored in the following way: … .5. If the regulator is faulty, you can observe the following: … .6. Safe welding environment is obtained by … .7.
Welding operators should be dressed in … .8. To keep welding equipment running for decades, operator should do someoperations on a regular basis, such as … .Revision12Describe in detail the welding procedure which you are mostexperienced in. Follow the plan.ØØØØØthe task to dothe equipment requiredwork stagessafety measuresquality control105PART 7.
ADVANCED TECHNOLOGIESAND THE FUTURE OF WELDINGLead-in1Read the two opinions about the future of welding and say which oneyou support.The future looks promising forwelding. It remains and willcontinue to be a productive,cost-effective manufacturingmethod.As far as design will be more andmore efficient there will be noneed in joining parts by means ofwelding and it will see decline inuse.Reading 12You will read the text “The past, present and future of aerospace joinprocesses”. Before you read suggest your answers to the following questions.1. Why can welding be necessary on board of a spaceship?2. What kinds of welding methods, in your opinion, are good for use inspace?3.
Why is welding in space such a difficult task?3Read the text again and say what events relate to:Ø the pastØ the presentØ the futureFill the table. Some examples are given.The pastThe presentverifying the possibility testing in a flyingof thermal-cutting and laboratorywelding in space106The futurecompletely new methodsof nondestructive testingand diagnosing weldedstructuresSpace-Age Welding:The Past, Present and Future of Aerospace Join ProcessesBy B.E. PatonApril 10, 2003On Oct. 16, 1969, astronauts performed the world's first welding andcutting experiment in a depressurized compartment. In flight aboard theSoyuz 6 spaceship, they tested three welding processes with a semiautomaticVulkan unit (see Figure below): consumable electrode arc in vacuum, lowpressure plasma, and electron beam welding. They studied how to weldaluminum and titanium alloys and stainless steel.
They verified thepossibility of thermal-cutting these materials andinvestigated the behavior of molten metal and featuresof its solidification.This experiment convinced experts that theycould use automatic welding to produce permanent,tight joints in space. They expanded this work with aseries of investigations conducted under short-timemicrogravity conditions in flying laboratories andspace simulation test chambers. In 1973 NASAexperts conducted a flight experiment with electronbeam cutting, brazing, and welding in the Skylaborbital station.Space welding technologies have advanced since then.
In-space repairand construction of space facilities and their equipment and instrumentationwere defined in the 1980s. Another major area identified was producingadvanced materials in space with new or improved properties using differentheat sources.Over the years scientists and specialists had to address construction ofvarious experimental space vehicles, namely, orbital and interplanetarystations, radio telescopes, antennas, reflecting shields, and helio powergeneration systems - in outer space.In addition to the original problems of assembly and erection in outerspace, as well as their view of how long these vehicles would be used andincreases in the vehicles' weight and dimensions, specialists focused moreattention on preventive maintenance and repairs.Initial Welding ExperimentsThe first welding experiments conducted in space demonstrated thatarc welding processes, which were widely accepted on earth and at first were107promising, had unfavorable characteristics in space, such as unstable, weaklyconstricted arc discharge; unstable globular transfer; and increased weldporosity.During experimental retrofitting in simulation facilities-chiefly inspace simulation chambers placed in flying laboratories-the difficultiesrelated to these characteristics were successfully resolved.
Specializedwelding equipment and techniques also were developed for this purpose, andthe required welding consumables often were selected from those used in theaerospace industry.However, it was clear to space system developers that almost allmaintenance and repair of long-term flying vehicles - for which neither thescope of work needed nor the components to be repaired and restored areknown in advance-had to be performed manually with only partialmechanization. This increased specialists' interest in studying the possibilityof manual welding in space, which led them to consider which of the existingwelding processes to use.Welding processes such as electron beam, consumable andnonconsumable electrode arc in vacuum, flash-butt, hollow cathode, andhelio welding were tested in vacuum chambers and in flying laboratories atdifferent stages of experimental studies in the 1970s and 1980s.Technology and material versatility and minimal power consumptionultimately were deciding factors that led them to choose the electron beamprocess.
This process allowedtechnicians to perform operationsthat could be required to produce apermanent joint in open space:heating, brazing, welding, cutting,and coating deposition.But selecting this processdidn't solve all the problems. Asinvestigationsprogressed,thenumber of problems, technical andpsychological,increased.Anopinion existed that this process, which involves high-accelerating voltage,the possibility of X-ray radiation from the weld pool, and manipulation of asharply focused electron beam, couldn't be done manually.A series of experiments in a ground-based, manned space simulationchamber enabled the engineers to solve the key technological and hardwareissues and develop a flight sample of an onboard electron beam hand tool.
In1984 and 1986 this tool was successfully tried out on the outer surface of theSalyut 7 orbital complex (see Figure above).108Based on new engineering systems that corrected technical parametersand suppositions from the test engineers and crews during experiments in theSalyut station, engineers developed a new electron beam hand tool in the1990s. The tool passed lengthy testing at NASA's Marshall Space FlightCenter and Johnson Space Center. During testing in a flying laboratory and atzero buoyancy, as well as in a manned space simulation test chamber inRussia, the developers were able to solve almost all the technical andprocedural problems with the tool.Further Aerospace Welding ExplorationAlmost 40 years' experience of technology developments and theirapplication leads to the conclusion that in this new century, major,complicated space work will have to be addressed.
Welding technologies willbe of tremendous importance.Such technologies are partially in place, butfurther space exploration will require developingnew welding, cutting, brazing, and coatingprocesses. New exotic materials will be introducedin the new century, and their processing andjoining will require completely new technologies.A number of space operations can be performed remotely, using robotsand manipulators.Welding in space might become widely accepted only if completely newmethods of nondestructive testing and diagnosing welded structures can bedeveloped.
This can be supported by data banks that allow automaticselection of the process and computer simulation.Laser applications in space, including such hybrid processes as laser-plasmaand laser-arc welding, offer promise, especially diode lasers. Friction weldingand resistance seam-roller welding also are of interest.Advanced space systems will continue to be developed both on theground and in orbit. New welding and related processes and technologies willhave an important role in those developments.B.E. Paton is director of the E.O.
Paton Electric Welding Institute,Kiev, Ukraine.The E.O. Paton Electric Welding Institute is amultidisciplinary research institute that realizes fundamental and appliedresearch works and develops technologies, materials, equipment and controlsystems, rational welded structures and weldments, and methods andequipment for diagnostics and nondestructive quality control. Paton also ispresident of the National Academy of Sciences of Ukraine.109Vocabularyinstrumentationreflecting shieldpreventive maintenancearc dischargeglobularretrofittingdeposition5оснащение инструментами, приборами,аппаратурой,комплектинструментов,аппаратураотражающий экранпрофилактическое обслуживаниедуговой электрический разрядшаровидный, сферический, сфероидальный,шарообразныйподгонка, настройкаосаждениеSay if the following is true or false.1. The world's first welding and cutting experiment was carried out in theouter space.2.
Thermal-cutting of aluminium, titanium alloys and stainless steel isimpossible in space.3. Only automatic welding is of importance for aerospace.4. A flight sample of an onboard electron beam hand tool was produced as aresult of series of experiments.5. Space welding is used for maintenance and repair purposes.6Translate the following sentences into English.1.
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