This is a story about welding materials and equipment.
1. Read and translate the text.
1. Welding current is conducted from the source of power to the arc by an insulated copper or aluminum cable. A very flexible cable is used between the electrode 
holder and the welding machine. This cable is designed for welding service.
For grounding the welding circuit, a less flexible, but equally wear resistant cable is used. The size of the cables used in welding depends upon the type of the material to be welded and the distance of the source of power.
2. The electrode is an important component of the electric circuit. We know electrodes to be divided into consumable and non-consumable electrodes. Tungsten and carbon electrodes are non-consumable. In the case of carbon and tungsten arc welding a filler metal may be fed from aside to supply an additional metal to the molten pool. As for the consumable electrodes, they are produced in the form of metal rod or wire, and for this reason provide a filler metal.
3. All the consumable electrodes are divided into bare and coated electrodes. An important advantage of arc welding is in the protection that a special mineral flux composition provides for the molten deposit. It is know that metal electrodes for the covered with flux coatings produce stronger welded joints as compared with those made with bare electrodes.
4. As it was mentioned, the electrodes are held in a special device-an electrode holder. The electrode holder is a clamping device for holding the electrode and is provided with an insulated handle for the operation’s hand. It should be mechanically strong, light in weight and hold the electrode firmly in position during welding.
5. We know that the arc is very hot and therefore it throws off both light and heat. To protect the operator’s face and eyes from the direct rays of the arc it is necessary to use a face shield or helmet. These shield or helmets are produced of pressed insulating material black in colour. The shield should be light in weight and comfortable to the welder. Shields are provided with special welding coloured lens absorbing the infrared rays, special goggles are used by welder’s assistants, foremen, inspectors and others working near the welder.
6. In addition to the equipment and materials described above, there should be available steel brushes for cleaning welds, tools for removing scale and slag from the surface of the weld and other shop equipment. Of course, in any welding shop you may find the equipment for welding inspection.
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Vocabulary
Insulate – изолировать
Flexible – гибкий
Wear resistant – износостойкий
Consume – тратить, расходовать
Consumable electrode – плавящийся электрод
Composition – смесь, состав
Impurity – примесь
Float – плавить на поверхности
Eliminate – устранять, предотвращать
Handle – рукоятка
Shield – щиток (сварочный)
Helmet – шлем
Coloured – цветной
2. Match the title to each paragraph.
1. Electrode flux coating.
2. Electrode and their types.
3. Cables and their features.
4. Other welding equipment.
5. Protection of welder’s face and eyes.
6. Electrode holders.
3. Answer the questions
1. What of electrodes are applied in welding?
2. How is a filler metal provided?
3. What is the difference between the two of cables?
4. What will you say about the electrode holder?
5. How are the welder’s face and eyes protected from welding rays?
6. Say a few words about welding helmet.
Find the words
Insulateflexiblewearresistantimpurityfloathandlehelmetcoloured
The welding technique.
Read and translate the text.
If you want to join two metals by arc welding you should know the welding technique, i.e. the technological process of welding.
To begin welding it is necessary to strike an arc. The electrode held in a holder is brought in contact with the metal surface, withdrawn (separated) and held as so to create and maintain an arc. Since the space between the electrode and the base metal has highest resistance in the circuit, a tremendous amount of heat is developed by the electric arc at this point.
Intense heating results in melting the workpiece metal and forming a small molten metal pool or crater. The depth of the crater indicates the amount of penetration or depth of fusion.
Since the electrode is also melted by the heat of the electric arc, the electrode metal is deposited in a molten pool on the base metal. In this case the electrode metal served both electrical pole and the filler metal. As we see, the metal electrode supplies additional metal to the base metal, but in the case of carbon or tungsten arc, filler metal rod may be used, it being usually fed from aside.
After an electric arc has struck, it is maintained by a uniform continuous movement of the electrode toward the work to compensate for that portion of the electrode which has been melted and deposited in the weld. At the same time, the arc should be advanced at a uniform speed along the line of welding, i.e. the weld groove.
As for the metal in the crater, it is agitated and mixes the molten electrode metal with the base metal, forming a strong weld joint. After the weld is completed it is necessary to clean and inspect it.
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Vocabulary
Technique – техника, методика
Bring (brought) – подводить, подносить
Withdraw – отводить
Depth (deep) – глубина
Serve – служить
From aside – со стороны
Feed – подавать, подача
Uniform – равномерный
Advance – продвигаться
Clean – чистый, очищать
Groove – канавка, разделка
Maintain – поддерживать Molten weld pool cварочная ванна.
1. Answer the questions.
1. What welding is described in the text?
2. What electrode do we use in the process?
3. How many electrodes are applied in this method?
4. When is the arc created?
5. Is any gas used in this welding?
Find in the text.
1. Маленькая сварочная ванна 2. Равномерная скорость
3. Прочное сварное соединение 4. Присадочный металл
5. Плавление детали металла
Welding & Machine Trades .
1. Read and translate the text.
Welding is a skill used by many trades: sheet metal workers, ironworkers, diesel mechanics, boilermakers, carpenters, marine construction, steamfitters, glaziers, repair and maintenancepersonnel in applications ranging from the home hobbyist to heavy fabrication of bridges, ships and many other projects. A variety of welding processes are used to join units of metal. As a welder, you may work for shipyards, manufacturers, contractors, federal, state, county, and city governments, firms requiring maintenance mechanics, and repair shops. Welding, while very physically demanding, can be very rewarding for those who enjoy working with their hands. Welders need good eyesight, manual dexterity and hand-eye coordination. They should also be able to concentrate for long periods of time on very detailed work, as well as be in good enough physical shape to bend and stoop, often holding awkward positions for long periods of time. Welders work in a variety of environments, both indoors and out, using heat to melt and fuse separate pieces of metal together. Training and skill levels can vary, with a few weeks of school or on-the-job training for the lowest level job and several years of school and experience for the more skilled welding positions. Skilled welders often select and set up the welding equipment, execute the weld, and then examine the welds in order to make sure they meet the appropriate specifications. They may also be trained to work in a variety of materials, such as plastic, titanium or aluminum. Those with less training perform more routine tasks, such as the welds on jobs that have already been laid out, and are not able to work with as many different materials. While the need for welders as a whole should continue to grow about as fast as average, according the U.S. Bureau of Labor Statistics, the demand for low-skilled welders should decrease dramatically, as many companies 8 move towards automation. However, this will be partially balanced out by the fact that the demand for machine setters, operators and tenders should increase. And more skilled welders on construction projects and equipment repair should not be affected, as most of these jobs cannot be easily automated. Because of the increased need for highly skilled welders, those with formal training will have a much better chance of getting the position they desire. For those considering to prepare themselves to a meaningful welding-career, there are many options available. There are also different professional specialties and levels, that should be understood to make an informed choice. Some of these are: welder, welding machine operator, welding technician, welding schedule developer, welding procedure writer, testing laboratory technician, welding non destructive testing inspector, welding supervisor, welding instructor, welding engineer.
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2. Make a list of all the words in the text indicating:
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a) welding professions and levels: welder, welding machine operator, …
b) trades where welding skill is used: …
c) places/fields a welder can work at (in): …
d) personal qualities a welder should have:
Answer the questions.
1. What are the trades where welding skills are used? 2. Where can welders work? 3. What personal characteristics should welders have? 4. How does the environment in which welders work vary? 5. What does it take to be s low-skilled/skilled welder? 6. What are welders able to do in terms of complexity of tasks and variety of materials? 7. What are the job opportunities for low-skilled/skilled welders for the nearest future as specified by the U.S. Bureau of Labor Statistics? 8. What are the advantages of having formal training for making a welding career? 9. As you see, welding includes various professional specialties and levels. What is yours?
4. Translate the following sentences from Russian into English:
1. Сфера применения сварки охватывает большое количество областей промышленности. 2. Профессия сварщика требует физической выносливости из-за частой необходимости работы в нестационарных условиях. 3. Для того чтобы стать квалифицированным сварщиком, необходима длительная теоретическая подготовка и практический опыт работы. 4.Квалифицированный сварщик должен сам уметь подбирать необходимое сварочное оборудование, материалы и технику сварки. 5. Чем выше квалификация сварщика, тем больше количество материалов, с которыми он может работать, и разнообразнее виды выполняемых работ. 6. В настоящее время имеются большие возможности для освоения профессии сварщика.
Welding Skills
1. Read and translate the text.
A Welder permanently joins pieces of metal with metal filler, using heat and/or pressure. Welders join parts being manufactured, they build structures and repair broken or cracked parts, according to specifications. Job Related Skills, Interests and Values
• using and maintaining tools, material handling equipment and welding equipment;
• reading and interpreting blueprints;
• acquiring thorough knowledge of arc, gas and resistance welding theory;
• laying out, cutting and forming metals to specifications;
• preparing the work site;
• fitting sub-assemblies and assemblies together and preparing assemblies for welding;
• welding using shielded metal arc welding, gas metal arc welding, gas tungsten arc welding, flux core or metal core arc welding, submerged arc welding and plasma arc welding processes;
• carrying out special processes such as welding studs and brazing;
• ensuring quality of product/process before, during and after welding;
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