Read the Text and try to identify the main information:
Consumable electrode methods
One of the most common types of arc welding is shielded metal arc welding
(SMAW), which is also known as manual metal arc welding (MMA) or stick welding. Electric current is used to strike an arc between the base material and consumable electrode rod, which is made of steel and is covered with a flux that protects the weld area from oxidation and contamination by producing CO2 gas during the welding process. The electrode core itself acts as filler material, making a separate filler unnecessary. The process is very versatile, requiring little operator training and inexpensive equipment. However, weld times are rather slow, since the consumable electrodes must be frequently replaced and because slag, the residue from the flux, must be chipped away after welding. Furthermore, the process is generally limited to welding ferrous materials, though special electrodes have made possible the welding of cast iron, nickel, aluminum, copper, and other metals. The versatility of the method makes it popular in a number of applications,
including repair work and construction. Gas metal arc welding (GMAW), also known as metal inert gas (MIG) welding, is a semi-automatic or automatic welding process that uses a continuous wire feed as an electrode and an inert or semi-inert gas mixture toprotect the weld from contamination. Since the electrode is continuous, welding speeds are greater for GMAW than for SMAW. However, because of the additional equipment, the process is less portable and versatile, but still useful for industrial applications. The process can be applied to a wide variety of metals, both ferrous and non-ferrous. A related process, flux-cored arc welding (FCAW), uses similar equipment but uses wire consisting of a steel electrode surrounding a powder fill material. This cored wire is more expensive than the standard solid wire and can generate fumes and/or slag, but it permits higher welding speed and greater metal penetration. Shielded metal arc welding a pipe
Submerged arc welding (SAW) is a high-productivity welding method in which the arc is struck beneath a covering layer of flux. This increases arc quality, since contaminants in the atmosphere are blocked by the flux. The slag that forms on the weld generally comes off by itself, and combined with the use of a continuous wire feed, the weld deposition rate is high. Working conditions are much improved over other arc welding processes, since the flux hides the arc and no smoke is produced. The process is commonly used in industry, especially for large products.
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1. Answer the following questions and summarize the text:
1. What is arc welding?
2. What kind of current and electrodes are used in arc welding?
3. What is the welded region protected by?
4. Why is constant current power supply most often used for manual welding
processes?
5. What is the function of flux in shielded metal arc welding?
6. What are the main advantages and disadvantages of manual metal arc
welding?
True or false?
1. The process is commonly used in industry, especially for large products.
2. The versatility of the method makes it popular in a number of applications.
3. The process can be applied to a wide variety of metals, both ferrous and non-ferrous.
4. Electric current is used to strike an arc between the base material and consumable electrode rod.
5. One of the most common types of arc welding is shielded metal arc welding.
3. Complete the sentences:
1. One of the most common types of arc welding...
2. Electric current is used to...
3. Gas metal arc welding (GMAW), also known as...
4. The process is very versatile, requiring little...
5. The versatility of the method makes...
6. This increases arc quality, since...
7. The slag that forms on...
8. Working conditions are much improved over other arc welding processes, since...
9. Weld times are rather slow, since the consumable electrodes...
10. The electrode core itself acts as filler material...
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Точечная сварка
"SPOT WELDING"
Read the text
| 1.Welding refers to a process that is used to join two metal objects. 2.Spot welding is a form of welding that requires a unique welding machine. 3.This machine is designed with clamps that join two pieces of metal together with electrodes. 4.The electrodes are used to apply pressure and electricity into the metal objects. 5.This causes a spot weld to be formed with a metal nugget between the objects. 6.Elihu Thomson invented spot welding in 1877. 7. Mr. Thomson had determined that two sheets of metal could be fused together by applying pressure and electricity to a discrete point. 8.As the voltage is pumped into the metal material a nugget of melted metal is formed that is used as an epoxy element, securely binding the two objects. 9.This type of welding is most often used by large robotic devices when creating automobile body parts. 10.There are many types of spot welding machines available today. 11.These include both large floor-mounted welders and small portable welders. 12.Each type of welder includes an electrical power supply and special electrode rods. 13.The size of the weld nugget depends on the thickness of the electrode rods and the amount of pressure and time they are placed on a object. | 1.Сварка относится к процессу, который используется для соединения двух металлических предметов. 2.Точечная сваркиа является формой сварки, что требует уникального сварочного аппарата. 3. Данная машина разработана с зажимами, которые соединяют две части металла вместе с электродами. 4.Электроды используются для оказания давления и электроэнергии в металлических объектов. 5.Это приводит к точечной сварки должны быть выполнены из металла, самородок между объектами. 6.Элиу Томсон изобрел точечную сварку в 1877 году. 7.Г-н Томсон установил, что два листа металла могли быть объединены вместе, применяя давление и электричество к дискретной точке. 8. Поскольку напряжение закачивается в металлический материал самородок расплавленного металла образуется который используется в качестве эпоксидной элемент, надежно связывания двух объектов. 9.Этот способ сварки наиболее часто используется крупными робототехнических устройств при создании частей кузова автомобиля. 10.Есть много типов точечной сварки машин, доступных сегодня. 11. К ним относятся как большие напольные сварщиков и небольшой портативный сварщиков. 12.Каждый тип сварщика включает в себя электрический источник питания и специальных стержней электрода. 13. Размер сварного шва самородок зависит от толщины электродных стержней и количество давления и времени, когда они размещены на объекте. |
Part 2 .
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1. Read the Text:
Spot welding is a popular resistance welding method used to join overlapping metal sheets of up to 3 mm thick. Two electrodes are simultaneously used to clamp the metal sheets together and to pass current through the sheets. The advantages of the method include efficient energy use, limited workpiece deformation, high production rates, easy automation, and no required filler materials. Weld strength is significantly lower than with other welding methods, making the process suitable for only certain applications. It is used extensively in the automotive industry—ordinary cars can have several thousand spot welds made by industrial robots. A specialized process, called shot welding, can be used to spot weld stainless steel. Like spot welding, seam welding relies on two electrodes to apply pressure and current to join metal sheets.
2. Put 5 questions to the Text:
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3. Give the English equivalents :
1. Точечная Сварка является популярным методом контактной сварки используются для соединения рядовых листов металла толщиной до 3 мм
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2. Прочность сварного шва значительно ниже, чем для других способов сварки, делая процесс подходит только для определенных приложений.
3. Прочность сварного шва значительно ниже, чем для других способов сварки, делая процесс подходит только для определенных приложений.
4. Сварки, так и сварочный шов основывается на двух электродах для применения давления и силы тока, чтобы присоединяться к металлическим листам.
5. Он широко используется в автомобильной промышленности - обычные машины могут иметь несколько тысяч точечных сварных швов, сделанных промышленных роботов.
6. Специализированный процесс, называемый сварочным, можте быть использован для точечной сварки нержавеющей стали.
7. Преимущества метода: эффективное использование энергии, ограниченной деформации заготовки, высокие производственные показатели, легкость автоматизации, и нет всех необходимых расходных материалов.
8. Два электрода одновременно используется для крепления листов металла вместе и пропускания ток через письма.
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Сварка сопротивлением
"RESISTANCE WELDING"
1. Read the Text:
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