министерство образования и науки российской федерации

министерство образования и науки российской федерации
МИНИСТЕРСТВО ОБРАЗОВАНИЯ И НАУКИ РОССИЙСКОЙ ФЕДЕРАЦИИ
Курганский государственный университет
Кафедра иностранных языков технических специальностей
АНГЛИЙСКИЙ ЯЗЫК
Практикум
по развитию навыков чтения и перевода
для студентов 2 курса
технологического факультета специальности
«Оборудование и технология сварочного производства»
Курган 2005
2
Кафедра иностранных языков технических специальностей
Дисциплина: «Английский язык»
Составил: ст. преподаватель Мосталыгина С.Е.
Утвержден на заседании кафедры 25.02.2005г.
Рекомендован методическим советом университета
__________ 2005 г.
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Чтение сокращений, дробей, определительных групп (цепочек)
существительного.
1. Сокращения расшифровываются и переводятся следующим образом
AC
– alternating current
– переменный ток
d
– density
– плотность, удельный вес
DC
– direct current
– постоянный ток
0
– deg. – degree
– градус, степень
ER brazing – electric-resistance brazing – пайка с применением нагрева
пламени
f
– frequency
– частота
fce
– furnace
– печь
fl
– fluid
– жидкий
fpm
– feet per minute
– футов в минуту
ft
– foot
– фут (30,5 см)
GMA
– gas metal-arc welding
– дуговая сварка металлическим
welding
электродом в среде инертного
газа
GTA
– gas tungsten-arc welding – дуговая сварка вольфрамовым
welding
электродом в среде инертного
газа
hr
– hour
– час
ht
– heat
– теплота
i.e.
– id est=that is
– то есть
in
– inch
– дюйм (25,4 мм)
min
– minute
– минута
mp
– melting point
– температура плавления
oc
– oxygen cutting
– кислородная резка
pc
– per cent
– процент
SAW
– submerged-arc welding
– дуговая сварка под флюсом
t
– temperature
– температура
UT
– ultrasonic test
– ультразвуковой контроль
wt
– weight
– вес
TIG
– tungsten-inert-gas arc – дуговая сварка вольфрамовым
welding
welding
электродом в среде инертного
газа
0.1
– zero point one; nought point one; o point one
0.060
– zero point zero six zero; o point o six o
0.006
– o point two oes six
½
– one second; a half; a second
1/3
– one third; a third
3/8
– three eighth
4
2. Расшифруйте, прочитайте и переведите примеры с сокращениями и
дробями:
5 ftm, 8 min, 4 in, 700 deg, 3/5 in, 7 ft, 20 mm, 10 pc, 3 hr, 30% wt.
3. Некоторую трудность представляет перевод определительных групп
(цепочек) существительного, в которых определения, состоящие из одного
слова или группы слов, занимают место перед существительным-ядром.
Перевод рекомендуется начинать с существительного и затем идти
справа налево, задавая вопросы какой? чей? для чего? чего?. Например:
hear source – источник теплоты; joint face – поверхность соединения;
pressure vessel – сосуд, работающий под давлением; gas tungsten-arc
welding – дуговая сварка вольфрамовым электродом в среде инертного
газа
4. Чтобы найти определительную группу, нужно найти ее границы. Левой
границей может служить артикль, местоимение, предлог; правой границей
– сказуемое, причастие I и II, предлог. Например:
1. Inert-gas metal-arc welding is also known as “consumable-electrode inertgas arc welding”.
2. Submerged arc welding is performed with a continuous electrode and a
granular flux composed with or without alloying elements.
3. The lower melting point alloys are known as “soft” solders.
Text 1. WELDING
Чтобы хорошо ориентироваться в тексте и уметь извлекать
необходимую информацию, следует прочитать весь текст, чтобы иметь о
нем общее представление. При этом нужно опираться на такие
сигнализаторы, как заголовки, числовые данные, знакомую лексику,
интернациональные слова. За основу следует взять подлежащее,
сказуемое, дополнение, перевести их и только потом строить схему
изложения, выбирая наиболее важные факты, сокращая или объединяя
отдельные предложения.
1. alloy
2. area
joint area
3. brazing
4. coalescence
5. face
joint face
6. joint
welded joint
7. metal
base metal
– сплав
– место сварки, зона сварки
– пайка, пайка твердым (тугоплавким) припоем
соединение, сращивание
– поверхность шва (соединения)
– соединение, стык, шов
– сварное соединение
- основной метал
5
filler metal
8. to melt
9. point
10. pressure
11. process
welding process
arc-welding process
gas welding process
12. soldering
13. source
heat source
14. weld
15. welding
arc welding
braze welding
explosion welding
forge welding
friction welding
induction welding
resistance welding
ultrasonic welding
- присадочный метал
- плавиться
- точка, конец, острие
- давление, усилие
- сварочный процесс, сварка
- дуговая сварка
- газовая сварка
- пайка, пайка мягким (легкоплавким
- источник теплоты
- сварной шов, сварное соединение
- дуговая сварка
- пайка-сварка
- сварка взрывом
- кузнечная сварка
- сварка трением
- индукционная сварка, сварка индукционным
нагревом
- электрическая контактная сварка
- сварка ультразвуком
Not until comparatively recently was the value of welding as a standard
method of joining metal as well as nonmetal pieces fully appreciated1. It was
during World War I that2 the various welding processes came into their own3
because speed of production in every metal-using and metal-fabricating
industry became a vital factor.
At first welding was limited to small or less important arts. Welding (1940) is
employed for an almost limitless number of application including ships,
structures and trains. The subject of welding may be divided into many
processes.
There are more than 84 distinct welding processes in use today. Most of
them employ one or more of the following principles to produce the welded joint.
The joint faces are progressively melted, causing them to flow together. A
filler metal having the same characteristics as the parts to be joined (base
metal) is commonly, but not always simultaneously melted to fill the joint area.
Various arc and gas welding processes, among others use this principle.
The joint faces are heated to a temperature below their melting point but
sufficiently high (above 8000F)4 to melt a filler metal to fill the joint. The filler
1
was the value of welding … fully appreciated – здесь: нарушение твердого порядок слов с целью выделения
it was … that – эмфатический оборот, эквивалентный русскому «именно»
3
came into their own – получили должное
4
Перевод температуры из градусов шкалы Фаренгейта (F) в градусы шкалы Цельсия (С) рекомендуется считать по
формуле: С=5/9 (F – 32); I0F=5/90 C
2
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metal must be an alloy that will produce coalescence. The coalescence, or
growing together of the parts joined, is the feature that distinguishes welding
from mechanical or adhesive bonding. Brazing and braze welding satisfy these
conditions. Soldering does not and therefore is not considered a welding
process5.
The joint faces are heated to a plastic, semimolten, or molten condition, and
pressure is applied to complete the weld. Forge welding, resistance welding,
and, to some extent, induction welding fall in this category.
Various forms of mechanical energy are used to squeeze, press or rub the
joint faces into an intimate contact that results in a coalescence at the joint. In
ultrasonic welding some pressure is used, but most of the energy comes from
mechanical vibrations at the frequency of ultrasound. Friction welding employs
the heat of friction obtained by rotating one part against the other, under
pressure, until melting begins. In explosion welding there is some relative
motion between the joint faces while under great pressure and, consequently,
heat is generated. In these processes no outside heat source is used.
5. Read the text once more, then check up your understanding of the main idea
of the text. Answer the questions.
1) What distinguishes welding from mechanical or adhesive bonding?
2) What welding processes use the principle of heating the joint faces and
applying pressure?
3) In what processes is no outside heat source used?
6. Повторите Passive Voice. Формула: to be + III форма смыслового
глагола. Составьте предложения по содержанию текста, подбирая
подходящие по смыслу группы слов из 2-4 столбиков. Пассивную
конструкцию рекомендуется переводить неопределенно-личной или
личной форме глагола в действительном залоге, причем подлежащее
пассивно.
1. The value of welding
2. Welding
3.The subject of welding
4. The joint faces
5. A filler metal
6. Soldering
7. Pressure
8. Heat
9. Heat source
5
must be
can be
progressively
may be
is
commonly
(not)
are
fully
was
were
simultaneously
divided (into) …
melted …
employed (for) …
applied …
appreciated …
considered
used
generated
heated
limited
Пайка легкоплавким (мягким) припоем не удовлетворяет этим условиям и поэтому не считается процессом
сварки.
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7. Переведите следующие предложения из текста, обращая внимание на
инфинитив в функции обстоятельства цели. При переводе вставляйте
союз «чтобы».
1. Most of welding processes employ one or more of the following principles
to produce the welded joint.
2. A filler metal having the same characteristics as the base metal is
commonly, but not always simultaneously melted to fill the joint area.
3. The joint faces are heated to a temperature below their melting point but
sufficiently high to melt a filler metal to fill the joint.
4. The joint faces are heated to a plastic, semimolten or molten condition,
and pressure is applied to complete the weld.
Text 2. ELECTRIC ARC WELDING
1.
2.
3.
4.
5.
6.
7.
8.
9.
surface
to invent
owing to
bonding
carbon arc
to bring about
power-engineering
manufacture
maintenance tool
– поверхность
– изобретать
– благодаря
– соединение, связь
– угольная дуга
– осуществлять
– энергетика
– производство
– ремонтный инструмент
Read the text, translate it and answer the questions.
Electric arc welding is a process in which surface to be joined are fused
together by the heat of an electric arc. The electric arc was invented in 1802 by
the famous Russian scientist V.V.Petrov, who demonstrated the possibility of
utilizing its heat for fusing metals. Petrov’s arc began to be practically used for
the welding of metals owing to the outstanding researches of N.N.Benardos and
N.G.Slavjanov. In 1882 Benardos invented a method of bonding and dividing
metals by the direct action of electric arc, i.e. electric arc welding and cutting of
metals by means of a carbon arc. He carried out welding not only with a carbon
electrode but with a metal electrode as well and indirect action of electric arc.
Arc welding, which fifty years ago was a process known to few specialists
has brought about a veritable technical revolution in heavy engineering,
shipbuilding, power-engineering, in fact, in any branch of our national economy.
Arc welding is used today in so many important industries that “if all arc welding
were suddenly stopped, all the industry, transportation and public services
would fall apart”. This is understandable, since welding is used not only for
manufacture of almost everything made of metal, but it is the maintenance tool
which keeps our railroads, steel mills, power plants, air liners and space ships,
motor cars and home appliances.
8
1. What is electric arc welding?
2. When was the electric arc invented?
3. When was a method of bonding and dividing metals invented and by
whom?
4. What electrodes were used in welding?
5. Where is arc welding used nowadays?
Text 3. AUTOGENOUS (GAS) WELDING
1.
2.
3.
4.
5.
6.
autogenous welding
flame
torch
to ignite
mixing chamber
low-pressure torch
7. equal
8. to deliver
9. velocity
10. suction
11. ratio
12. rightward welding
13. leftward welding
14. additive
15. implement
- автогенная газовая сварка
- пламя
- сварочная горелка
- зажигать(ся), воспламенять(ся)
- смесительная камера (газовой горелки)
- горелка низкого давления, инжекторная
горелка
- равный
- доставлять, поставлять
- скорость
- всасывание
- отношение, коэффициент
- сварка правым способом, правая сварка
- левая сварка
- присадка
- инструмент, прибор
Read the text and answer the following questions:
1. What is the source of heat for autogenous welding?
2. What gas is used in autogenous welding?
3. What types of welding torch are mentioned in the text?
4. What is rightward welding?
5. What is gas welding used for?
In autogenous welding the source of heat is the gas flame obtained from a
gas which is often acetylene. Acetylene mixed with oxygen in a torch when
ignited gives a steady flame. The welding torch consists essentially of a gas
mixing chamber and is designed in two types: the low-pressure injector type
and the equal-pressure type. In the injector-type torch the acetylene is delivered
at very low-pressure and the oxygen enters the torch at high pressure and
velocity expanding in the mixing chamber. Then the acetylene is drawn by
auction created in the mixing chamber in a constant ratio to the oxygen.
Autogenous welding is carried out in different ways and methods.
According to the movement of the torch, welding may be divided into rightward
welding and leftward welding. In rightward welding the torch moves ahead of
the additive, and in leftward welding the additive moves in front of the torch.
9
Gas welding may be used for cutting metals and repairing agricultural machines
and implements.
Text 4. ATOMIC-HYDROGEN WELDING
1. atomic-hydrogen welding
2. sheet metal
3. worn surface
4. rod
5. parent metal
6. heat
7. tungsten electrode
8. alternating current
9. to melt
10. to cool
11. to joint
12. to protect
13. the molten metal
14. flux
15. stream of hydrogen
- атомно-водородная сварка
- листовой металл
- изношенная поверхность
- пруток, электродный стержень
- основной (родственный) металл
- тепло
- вольфрамовый электрод
- переменный ток
- плавить(ся)
- охлаждать
- соединять
- защищать
- расплавленный металл
- флюс
- поток водорода
1. Read and retell the text given below.
Atomic-hydrogen welding is an arc welding process in which unusually
clean welds can be obtained. The process is particularly applicable to the
welding of sheet metal, thin and moderate wall tubing, and to repair welding of
the worn surfaces. The process may be used with or without filler rods. An
advantage in repair welding is that sound dense deposits of properties of the
parent metal can be produced with proper selection of filler material.
In the atomic-hydrogen process the heat of an arc is used indirectly as a
source of welding heat. An arc is established between two tungsten electrodes
using alternating current. At the same time, streams of hydrogen gas are
passed along the electrodes, through the arc, and toward the base metal to be
welded. The arc heats the hydrogen to a high temperature, perhaps 9,000° F.
Leaving the arc, the hydrogen strikes the metal to be welded, raising its
temperature and melting it, using the additional heat of combination. At high
temperatures molecules of hydrogen fall apart.
The arc in atomic hydrogen welding heats the metal not only by imparting
its thermal energy, but also by the heat of combination of hydrogen atoms. The
hydrogen also serves as a shielding gas to protect the molten metal from the
atmosphere. The metal being welded is surrounded by hot hydrogen.
2. Make up written translation of the first and the second paragraphes.
10
Text 5. SUBMERGED-ARC WELDING
1. submerged-arc welding
2. consumable electrode
3. powdered flux
4. granulated flux
5. bare electrode
6. feed
7. blanket
the blanket of flux
8. jaw
9. wire
10. hopper
11. to solidify
12. slag
13. to float
- дуговая сварка под флюсом
- плавящийся электрод
- порошкообразный флюс
- гранулированный флюс
- оголенный электрод
- подача;
to feed (fed) – подавать
- поверхностный слой
- флюсовое покрытие
- кулачок
- проволока
- бункер
- затвердевать
- шлак
- плавать, держаться на поверхности
Very early in the progress of electric arc welding, a need was recognized
for some form of protection for the weld metal from the atmosphere. The first
developed methods were coatings applied to the consumable electrodes of
hand welding. After this came various attempts to introduce mechanization to
the welding process. The first powdered fluxes that were developed for
separate introduction into the weld zone, while a base metal material was
continuously and mechanically fed, frequently produced a very vigorous arc
action with sparking and spattering metal.
Bur gradually more satisfactory fluxes, techniques and processes were
developed and one of such welding processes that have come into wide use is
the submerged-arc or submerged-melt process. In this process, a specially
manufactured granulated flux is deposited on the joint to be welded, of sufficient
depth to complete cover the end a bare metallic electrode, shielding the arc
during the welding operation. The entire welding action takes place beneath the
blanket of flux without sparks, smoke, spatter, or flash, and the electrode is fed
by power into the granulated material at an automatically controlled rate,
depending on the required length of arc.
The welding heat for the submerged-arc process is generated by the
passage of an electrical AC or DC current between the end of a bare electrode
wire submerged in a finely granulated flux or slag and the base metal to the
welded.
Operation. A bare electrode wire, coiled on a reel of 60 or 200 lb and in
diameters ranging from 5/64 in to ¼ in, is fed by mechanically powered drive
rolls continuously into the arc. Current is fed to the wire through contact jaws
between which the wire passes. An arc is formed between the electrode and the
work. The arc is completely covered at all times by the flux, which is deposited
continuously, from hopper, around the wire as it is fed to the work. The arc
melts the electrode and the base metal. When the current flows through the
11
circuit, a portion of the granulated flux surrounding the electrode end becomes
molten. This molten blanket of material is very effective in shielding the arc and
the molten metal from the atmosphere. The melted flux adjacent to the arc
floats on the surface of the molten metal and solidifies in the form of slag on the
top of the weld. After the weld is completed, the slag is readily removed from
the weld.
1. Answer the following question.
1) What arc did the first powdered fluxes produce?
2) How is the molten deposit protected in this process?
3) What wire is used in submerged-arc welding?
4) What material is deposited to cover the joint from atmosphere?
5) Are there any sparks, spatter and flash during the welding action?
6) How and where is the welding heat generated?
7) What current is used in submerged-arc welding?
8) How is current fed to the wire?
Additional text
Read the text and tell a few words about the equipment used in submerged-arc
welding, the power sources and advantages of the process.
Equipment
Equipment is available for both fully automatic operation, as well as
semiautomatic operation, wherein wire feed is automatic, but the travel speed
and direction is controlled by hand rather than machine. For manual operation,
which is sometimes done, the electrode wire is fed through a flexible tube by a
wire driving mechanism.
Automatic heads are available for operation with either AC or DC and for
either shop or field operation. The heads can be mounted stationary while the
work is moved in relation to the electrode, or the head can be moved in relation
to the work. Two or more heads can be mounted together to create multiple arc
in tandem, which still further increases the rate of deposition.
Power sources for welding heads include transformers, motorgenerators
and rectifiers.
Since the arc and the weld metal are completely shielded from the air by
the blanket of flux, uniform and high quality welds are produced. In addition,
greater penetration is provided because of the higher concentration of the heat
due to the insulating qualities of the flux. The flux blanket also controls the bead
shape and allows the use of much higher current densities than can be
employed with an open arc. The high currents, of course, lead to deep
penetration of the base metal and fast deposition of electrode wire. Since a
large amount of material is molten in one time, it is essential that the weld be
done in a horizontal or flat position.
12
Text 6. ELECTRODES
1. to bear in mind
2. brittle
3. to prevent
4. to surround
5. bare electrode
6. to encounter
7. powdered flux
8. coated electrode
9. core wire
10. to convey
11. fatigue
12. to facilitate
- помнить
- хрупкий
- предотвращать, препятствовать
- окружать
- электрод без покрытия
- встречаться
- порошкообразный флюс
- покрытый электрод
- электродный стержень, электродная проволока
- передавать
- усталость
- облегчать, способствовать
1. Read the text and find out:
1) в каком абзаце говорится о том, что необходимо сделать для
получения наплавленного металла хорошего качества;
2) в каком абзаце говорится о том, от чего зависит успех сварочной
операции;
3) в каком абзаце говорится об электродах без покрытия.
When considering electrodes it is necessary always to bear in mind the fact
that heated metal combines chemically with oxygen and nitrogen from the
atmosphere, forming oxides and nitrides which result in brittle, poor-quality weld
metal. For this reason it is essential to provide some means of preventing the
atmosphere from reaching the hot weld area. This can be done either by
surrounding the area with an inert gas or by the use of a suitable flux.
Metal-arc welding was originally done with bare electrodes consisting of a
piece of wire or rod of the same composition as the metal to be welded. For the
reason mentioned above, the welds were of poor quality, and thus bare
electrodes are now rarely encountered. Bare wire is used for automatic welding,
but in this case the welded area is protected from the atmosphere by either
powdered flux or an inert gas.
Most modern electrodes are of the coated or covered type, consisting of a
metal core wire surrounded by a thick coating. To a large degree, the success
of the welding operation depends on the composition of the coating, which is
varied to suit different conditions and metals.
An electrode holder is simply a clamping device for holding the electrode,
the welding current being conveyed through the holder to the electrode. The
clamping portion must be so designed as to hold the electrode securely, yet
permit it to be changed quickly and easily. It should be light in weight in order to
reduce fatigue and facilitate ease of handling.
2. Tell a few words about different types of electrodes.
13
Text 7. TIN-LEAD SOLDERS
1. means
2. solder
3. to perform
4. application
5. expensive
6. ordinary
7. constituent
8. weldability
9. reduction
10. price
11. careful
12. tangible
13. saving
14. low-grade alloy
- средство
- припой
- выполнять
- применение
- дорогой
- обычный, простой
- составная часть
- свариваемость
- сокращение, уменьшение
- цена;
cost
- цена, стоимость
- тщательный
- реальный, ощутимый
- экономия
- сплав низкого качества
1. Read and translate the text.
As a practical means of joining, soldering is easy to perform and is widely
used. Solders have found applications from the most expensive electronic
equipment to ordinary car radiators. In these diverse fields, a relatively few
solder alloys are used, based on tin in varying proportions (30 to 63 wt-% is the
tin content range in normal applications).
Tin is essential in the currently used solder alloys, as the constituent that
ensures weldability of the allow relative to the base material. High service
temperatures are common in modern electronic assemblies, with levels around
70oC tolerated by components under continuous work conditions, and even
higher ones over short periods.
These solder alloys are by no means perfect. The price of tin used to be
high until a few years ago, and even after its reduction, it still dictates the end
cost of solder alloys. Several attempts to reduce the tin content have been
made and straight tin-lead solders have very good welding properties.
Careful selection of the right solder for a specific selection can make for
tangible savings, especially with lower-grade alloys, which can be replaced by
the inexpensive alloy, without undesirable consequences.
2. Retell the text according to the plan:
a) The application of solders;
b) The proper selection of solders.
14
Text 8. ELECTRIC SLAG WELDING
1. downhand position
2. repair work
3. building-up
4. worn
5. to cast
6. saving
7. order
8. trend
9. weight
10. waste
11. capacity
12. to expand
13. to impair
- нижнее положение
- ремонт
- монтаж, сборка
- изношенный
- отливать; casting - отливка
- экономия
- порядок
- направление, тенденция
- вес
- потеря, убыток
- мощность, производительность, нагрузка
- расширять(ся)
- ухудшать(ся)
1. Read and translate the text.
Originally, electric slag welding was applied to vertical joints, where they
could not be welded in the downhand position convenient for the are process.
Its efficiency soon made the electric slag process a basic method for welding
heavy sections. Electric slag welding is now employed to make welds in both
production and repair work, for the building-up of worn surfaces and for special
purpose casting.
In some cases welded structures mean a saving of metal. However, the
advantages of electric slag welding are not only of a purely economical order.
Its use has radically changed the trend of development in heavy engineering. In
recent years, the requirements of various industries have been running ahead
of what heavy engineering was able to offer in terms of size and weight of large
machines and structures. In most cases, the size of machine elements is limited
by the maximum weight of molten metal that can be casted. The weight may be
much larger than that of the finished product due to the waste of metal. In turn,
the maximum weight of a casting is limited by the lifting capacity of the cranes
available, the capacity of melting furnaces, and by the fact that the quality of
metal is impaired as size of a casting increases.
The size and weight of machine elements could be increased, if the above
listed production capacities were expanded in proportions. Electric slag welding,
however, offers an entirely different approach.
2. Agree or disagree with the following statements:
a) The advantages of electric slag welding are only of a purely economical
order.
b) Electric slag welding is now employed only for repair work.
c) Its high efficiency soon made the electric slag process a basic method for
welding heavy sections.
d) The quality of metal is impaired as size of a casting reduces.
15
Text 9. SOLDERING
1.
2.
3.
4.
5.
6.
7.
8.
9.
soldering
solder
nonferrous metal
tin
lead
to add
soldering iron
strength
to ensure
- пайка легкоплавким припоем
- припой, мягкий припой
- цветной металл
- олово
- свинец
- добавлять, дополнять
- паяльник
- прочность, сила
- обеспечивать
1. Read and translate the text.
Soldering is a group of metal joining processes wherein the filler metal is a
nonferrous metal or alloy whose melting point is below 700oF. The usual filler
metal is solder, an alloy of tin and lead in various proportions. Small quantities
of certain other metals may be added. Since solder melts at a relatively low
temperature, it is easier to apply than the filler metal in brazing. Ordinary gas
flames and electric resistance-heated soldering irons may be used to supply the
required heat. The fluxes used with soldering include rosin, zinc chloride and
other substances.
Most metals, such as iron, steel, copper and copper alloys can be joined by
soldering. The strength of soldered joints is relatively low and is determined by
the strength of the soldering metal. Soldering is most commonly used to ensure
good electrical contract in joining wires and small parts.
2. Answer the following questions.
1) What is soldering?
2) What fluxes are used in soldering?
3) How is the strength of soldered joint determined?
4) Where does soldering find its application?
Text 10. ELECTRODE HOLDERS
1. a multipurpose tool
2. to hold (held)
3. to remove
4. to insert a fresh electrode
5. copper lug
6. handle
7. in addition to
8. welder
9. to insulate
10. to grip
- многоцелевой инструмент
- держать
- удалять
- вставлять новый электрод
- медное ушко
- рукоятка, ручка
- кроме
- сварщик
- изолировать
- зажимать
16
- тиски
- максимальный срок службы
11. jaw
12. maximum life
The metal-arc electrode holder is in reality a multipurpose tool. Besides
holding the electrode security during welding, it must also be so constructed as
to provide an easy means of removing the burned stub and inserting a fresh
electrode. This electrical contact as is provided at the holder cable connection.
Usually, the cable is connected to a copper lug within the handle by a
mechanical or soldered joint.
There are many requirements for an electrode holder in addition to giving
the welder a convenient means for holding and guiding the electrode. An
important point is that the welding current must be conducted from the cable
connection to the electrode with a minimum of resistance: otherwise there will
be heat, which might make the electrode holder too hot for comfortable use.
An insulated handle will, of course, reduce the heat effect. On some
holders, the entire holder is insulated to reduce the possibilities of electrical
shock during welding.
The electrical contact between the metal-arc electrode and electrode
holder is obtained in one of several ways. The more common method is to grip
the electrode between two jaws by means of pressure exerted by a powerful
spring. In another jaw-type holder, the gripping pressure is provided by a screw
and cam action. A third type of holder eliminates jaws by having the electrode
inserted in a hole, where it is held in place by screw action to insure good
electrical contact.
Some holders are distinctive in character and designed to do a specific job.
Though electrode holders may look different they serve the same purpose.
Tell about: a) the metal-arc electrode as a multipurpose tool;
b) the requirements for an electrode holder.
Text 11. ULTRASONIC TESTING
1.
2.
3.
4.
5.
6.
7.
8.
to detect
flaw
sensitivity
non-destructive testing
semi-skilled
pulse
duration
transducer
9. to impinge
10. scanning
- обнаруживать, выявлять
- трещина, дефект
- чувствительность
- испытание без разрушения образца
- полуквалифицированный
- вибрация, импульс
- продолжительность
- преобразователь, щуп ультразвукового
дефектоскопа
- ударяться, падать
- перемещение щупа при ультразвуковом
контроле
17
1. Read the text and find the answers to the following questions.
1)
2)
3)
4)
В связи с чем упоминается имя инженера Соколова?
В чем заключаются преимущества ультразвукового исследования?
Из чего состоит ультразвуковое оборудование?
Чем
оснащены
новейшие
приборы,
используемые
при
ультразвуковом исследовании?
The Russian engineer Sokolov was the first to have used ultrasonic
vibrations to detect flaws in metals. And indeed, in the last few years, the use of
ultrasonic has grown greatly. This method of welding examination has some
advantages over other forms of examination.
The equipment is easily portable, it is safe to use, there is no radiation
hazard, it has a high sensitivity factor and it is speedy. It is an economical form
of non-destructive testing of welds. It can by used by semi-skilled operators in
its general application.
The ultrasonic equipment consists of a pulse generator which products
ultrasonic pulses of very short duration, usually in a range from 1 to 3 microseconds.
These pulses are sent out from a quartz crystal transducer to the medium
under test. When the beam impinges upon any interface or detect, part of the
energy will be reflected, received by the instrument, recorded and indicated on
the ultrasonic screen. The latest productions of ultrasonic instruments are
equipped with a recording device, a manual scanning is being superseded by
automatic scanning.
Text 12. SAFETY RULES AND PROTECTIVE EQUIPMENT
1. safety
2. hazard
3. cutting
4. fume
5. to subject
6. canvas
7. gloves
8. apron
9. ray
10. burn
11. shield
12. to remove
13. goggles
14. to eliminate
15. to strike
- безопасность
- риск
- резка
- дым
- подвергать
- брезент
- перчатки
- фартук
- луч
- ожог
- защита
- удалять
- очки
- ликвидировать, уничтожать
- зажигать
18
There are hazards in welding and cutting, just as there are hazards in any
industrial operation. It is evident that the welding arc is very hot (temperature of
6,000 deg F.) and therefore it throws off both light and heat. The arc welder and
the flame-cutting operator are exposed to fumes and to intense radiation of heat
and light. In addition, they are subjected to the hazards of burns and electric
shocks. It is necessary that proper protection be used.
Each welder must observe simple safety rules:
1. Whenever a welder is working around an open flame or an arc, he
should wear clothing that will minimize the danger of fires starting. Woolen and
canvas clothing, leather gloves, aprons and jackets can be worn as a protection
from sparks, spatter or slag. Trousers without cuffs are advisable. No part of the
bode must be exposed to arc rays, as they will cause serious burns.
2. To protect the operator’s face and eyes from the direct rays of the arc, it
is essential that a head shield be used. These shields or helmets are generally
constructed of some kind of pressed fibre insulating material, dead black in
colour to reduce reflection. The shield should be light in weight and designed to
insure greatest possible comfort to the welder. Protective shields are provided
with suitable coloured lens absorbing the infrared rays, the ultra violet rays and
most visible rays emanating from the arc. The coloured welding lens should be
protected by any ordinary clear cover glass. Besides, goggles must be worn by
the welder at all times because they are necessary to protect his eyes when
removing slag from welds, either before or after welding.
3. Welding should be performed in separate rooms or in locations where
screening is possible in order to eliminate the danger of eye injuries from
reflected or direct rays of the arc to other workers. Where many welders are
working, the welder should show consideration of his fellow workmen when
striking the arc.
4. Artificial ventilation should be installed to carry off the fumes and to
insure good visibility when welding is done in smaller shops, and other
restricted spaces, particularly inside tanks, boilers, pipe tunnels, etc. Ventilation
is especially necessary if materials bearing zinc, lead or cadmium are to be
welded. In the cases where adequate ventilation system cannot be provided, a
proper type of filter respirator will give the welder adequate protection.
Answer the questions to the text.
1. What hazards is the arc welder exposed to in welding?
2. What can you say about welder’s clothing?
3. How are the welder’s eyes protected from the heat and the rays?
4. Is it dangerous to remove slag without goggles?
5. Where should screening be used?
6. Under what conditions must welding be performed?
7. Where is artificial ventilation especially necessary?
8. What should welders remember when welding?
9. What safety rules should each welder observe?
19
Text 13. SPOT WELDING WITH ROBOTS
1.
2.
3.
4.
5.
6.
7.
8.
spot welding
to perform
to decrease
extra
to sense
appropriate
reliable
accuracy
precision
9. accessory
accessories
10. tip wear
- точечная сварка
- выполнять
- уменьшать(ся)
- дополнительный
- чувствовать, ощущать
- соответствующий, подходящий
- надежный
- точность, правильность
- точность, четкость
- приспособление
- арматура, принадлежности
- износ наконечника
1. Read the text and tell a few words about the advantages of robotic spot
welding systems.
Spot welding is one of the most widely accepted applications for robots.
Robotic spot welding system results in improved quality, increased productivity
and reduced costs. Typically, robots can perform 30 to 60 spot welds per
minute.
Robotic spot welding systems lead to increased productivity and higher
quality welds. So robot users find they can decrease the total number of welds
required on a part because there is no longer a need for those extra welds.
Product quality is the key point.
Robots can be equipped to sense which parts are coming next and
automatically switch to the appropriate program. We need a robot that is highly
reliable, capable of accuracy and precision repeatability and available with
accessories and spot welding programs. Programs can compensate for tip wear
and can adjust the angles of welding tips when necessary. Speed is important
but speed between welds is more important than top speed because it more
directly influences the overall efficiency of the system.
Text 14. UNDERWATER WELDING
1.
2.
3.
4.
5.
6.
7.
8.
underwater welding
to strike an arc
resistance
bubble
weld pool
to cause
circuit
layer
- сварка под водой
- зажигать дугу
- сопротивление
- пузырек
- сварочная ванна
- вызывать
- цепь
- слой
20
9. diving suit
10. D.C. – direct current
11. A.C. – alternating current
12. ductility
- водолазный костюм
- постоянный ток
- переменный ток
- гибкость
What is underwater welding process?
Welding under water may appear to be difficult and hazardous operation,
but as a rule, it is no more difficult than surface welding.
When the welding arc is struck under water, the heat caused by the
electrical resistance between the electrode and the plate causes the water
immediately in the heated area to boil. This forms a bubble of steam across
which the metal arc and the gases can flow to the weld pool. The intense heat
causes some of the steam to dissociate into oxygen and hydrogen: these gases
mix and burn.
Complete insulation of the welding circuit is essential. The electrode
coatings are protected by a layer of max, varnish or cellulose. The layer also
ensures that the coatings do not disintegrate while under water. Such insulation
is also necessary because the diving suit has many exposed metal parts and
the diver in the suit is effectively earthed by the surrounding water.
D.C. welding is employed, as it is safer than A.C. Electrolysis of the water
can occur, with consequent electrolytic attraction to the metal parts of the diving
suit, and to counteract to the negative pole of the supply current. Underwater
welding is restricted to mild steel, but when properly carried out the weld should
have about three-quarters the tensile strength, and at least half the ductility of a
similar surface weld.
Text 15. THE PLASMA ARC CUTTING PROCESS – HOW IT WORKS?
1. plasma cutting
2. cooled nozzle
3. power unit
4. flexible hose
5. pilot arc
6. jet
7. proximity
8. to eject
9. to transfer
10. to insert
11. density
12. performance
- плазменная резка
- охлажденный наконечник
- силовая установка
- гибкий шланг
- вспомогательная дуга
- струя; форсунка
- близость
- выпускать, выбрасывать, извергать
- перемещать, переносить
- вставлять, включать
- плотность
- выполнение
1. Read and translate the text.
21
Plasma cutting is achieved by means of a concentrated electric arc in a
flow of gas. The arc is concentrated by passing it through a cooled nozzle which
makes it smaller in diameter and at the same time increase the voltage per unit
length, so that at a given current the power in the arc is higher than in a “free”
arc.
The practical realization of the process for cutting metals consists of a
power supply unit, a cutting torch containing an electrode and a nozzle
connected to the power unit by a flexible hose/cable set. A pilot arc is struck
between the electrode and the nozzle, giving a jet of conductive ionized gas.
When this is brought into the proximity of the workpiece a main arc transfers to
the workpiece, increasing the power in the arc and rapidly melting the
workpiece, in the path of the arc; the molten metal is ejected at high velocity of
the energy in the arc. The result is high speed cutting with low heat input into
the surrounding metal.
Historically the electrode has been made of tungsten and an inert or nonoxidising gas has been passed between it and the nozzle. It is possible to use
air as plasma gas with a zirconium or hafnium electrode. As these elements
melt at a lower temperature than tungsten they are inserted into copper holders
which are cooled with water. The use of air as the plasma gas increases arc
density and hence cutting performance as well as reducing operating costs
considerably.
2. Answer the following questions.
1) How is plasma cutting achieved?
2) What electrodes are used in plasma cutting?
3. Make up written translation of the second paragraph.
Text 16. THE ELECTRON BEAM WELDING
1. beam
2. stream
3. to carry out
4. contamination
5. chamber
6. device
7. gun
8. means
9. penetration
10. impurity
- луч
- поток
- выполнять
- загрязнение
- камера
- устройство
- ружье
- средство
- проникновение
- примесь
1. Read and translate the text.
The electron beam welding process was developed in recent years.
Introducing the electron beam is one of the most important developments in
22
welding. In this process a stream of electrons bombarding the metal surface
produces heat. The process is carried out in a vacuum and is therefore
extremely useful for welding metals highly sensitive to atmospheric
contaminations.
An electron beam welding machine consists of an electron optical column
and an evacuated chamber with devices for producing a focused beam of
electrons and for holding and moving a workpiece. The electron optical column
consists of four separate sections. The top section is the electron gun used for
producing the beam; in the section below. the beam is focused; the third section
is a microscope. In the bottom section there are means for aligning and
focusing the beam on the workpiece.
Beam of electrons streams on the surface causing melting and forming a
crater at the metal surface. Forming this crater results in very high penetration.
Since metal is melted in vacuum, contamination from the atmosphere does not
occur. The fused zone is more pure than the parent metal since impurities boil
off at the high temperatures. The joints are strong and free from porosity and
slag inclusions.
The electron beam equipment is quite safe for operator. There are three
main advantages of electron beam welding:
1) The process is carried out in vacuum. This is useful when joining those
metals and alloys which are highly sensitive to the effects of small
concentrations of hydrogen, nitrogen, oxygen and other atmospheric
contaminations.
2) Very great heat concentrations are obtained in the weld zone.
3) Great control of the heat input and its precise location is possible.
The main limitation of the process arise the fact that welding is performed
in a vacuum. The size of the workpiece is therefore limited by the size of the
vacuum chamber.
2. Answer the following questions.
1) What welding process is one of the most important developments of
modern science?
2) What does a stream of bombarding electrons produce on the metal
surface?
3) Is the process carried out in the atmosphere?
4) What does an electron beam welding consist of?
5) What are the main advantages of electron beam welding?
Text 17. BRAZING
1.
2.
3.
4.
brazing
nonferrous metal
soldering
carbon steel
- пайка твердым припоем
- цветной металл
- пайка мягким припоем
- углеродистая сталь
23
5.
6.
7.
8.
9.
cast iron
stainless steel
grease
powder
torch
- чугун
- нержавеющая сталь
- смазка
- порошок
- горелка
1. Read and translate the text.
Brazing is a group of metal joining processes wherein the filler metal is a
nonferrous metal or alloy whose melting point is higher than 1000o F., but is
lower than that of the metals or alloys being joined. Brazing, unlike welding,
does not require that the surfaces of the metal be welded; it differs from
soldering in that the latter method uses filler metals which melt below 700o F.
During brazing, the base metal of the two pieces to be joined is not melted:
Some diffusion or alloying of the filler metal with the base metal takes place.
The brazing process is widely used because a great many metals can be
effectively joined in that manner. Simple carbon steels as well as cast iron,
nickel, bronze, stainless steel, high-temperature alloys may be joined by
brazing.
Brazing materials commonly used fall into three broad groups: silver- and
copper-base alloys, nickel-base alloys, and gold-base alloys. The melting points
of these alloys range from 1150o to 2100o F.
The surface to be joined must be free of oxide and grease to obtain a good
bond. It is therefore necessary either to protect the surfaces from the oxidation,
which may occur during heating, or to use a flux which will remove oxide by
chemical means. The flux chosen should be highly fluid at the brazing
temperature, be readily floated to the surface of the brazing metal and, of
course, must react with the metal oxide.
Flux may be applied to the surface being joined before brazing or as a
powder with the brazing metal. After the flux is added, the joint is heated to the
proper brazing temperature. Solid filler metal may be preplaced on the metal
pieces and thus is melted as the metal pieces are heated, or it may be applied
to the metal pieces after brazing temperature is reached.
Heating for brazing may be done by oxyacetylene torch, in a furnace, by
dip technique or by electric means. The latter may be provided by the carbon
arc, electric resistance or induction methods.
2. Answer the following questions.
1) What is brazing?
2) What is the difference between brazing and welding?
3) What metals and alloys may be brazed?
4) What groups do brazing materials fall into?
5) What is the main purpose of using flux in brazing?
6) What requirements must the flux meet?
7) How is heating provided?
24
8) Is it possible to heat metals to be brazed by induction heating?
Text 18. WHY WELDING FUMES NEEDN’T BE A PROBLEM?
1.
2.
3.
4.
5.
6.
7.
8.
fume
unsafe
properly
to install
dust
exhaust system
treated air
to protect
protection
9. to blow away
10. hazard
- дым
- опасный, ненадежный
- правильно, должным образом
- устанавливать, монтировать
- пыль
- система выхлопа (выпуска)
- отработанный воздух
- защищать
- защита
- сдувать
- риск
Text A
There’s no reason today for welding shops to be dirty and unsafe. A
properly designed and installed fume collector means a much cleaner plant and
no health hazard to welders from toxic gases, fumes and dusts. The
advantages of a good fume collection system are evident. If the exhaust system
in a busy welding shop is turned off them the area can be filled up with fumes in
a few minutes. But, when the fume collectors are working properly, there should
be a complete absence of fumes. The treated air being recirculated with more
than 95% efficiency for particles smaller that one micron. Decisions on the type
of protection for the welder should be based on the fume measurements near
the work area and also the composition of the fumes. The welder can protect
himself by positioning himself so that the drafts, natural or inducted are blowing
away from him. He should use a headshield rather than a handshield. The
welder should wear some form of breathing protection.
Text B
1. degrease
2. paint
3. to expose to
4. extraction system
5. to dispose
6. contaminant
7. ducted system
8. to catch
9. to escape
10. hood
11. inlet
- смазка
- краска
- подвергать(ся)
- система вытяжки
- устранять, избавляться, ликвидировать
- примесь, загрязняющее вещество
- вентиляционная система
- ловить, уловить
- избегать
- вытяжной шкаф, кожух, чехол
- впускное отверстие, впуск, ввод
25
The majority of work today is still on steel but there is more on aluminium
and stainless steel which have more harmful fumes. A major hazard is fumes
from degreases or paints. This can be avoided if this work is done in a separate
area. Welding fumes are produced at the source point close to the welder
where he is directly exposed to the highest concentration of fumes.
A local extraction system is essential which safely disposes of the
contaminants through a ducted system before they reach the welder. The
general ventilation system catches the fumes that escape local extraction. This
system also protects other workers in the area and reduces the need for a
supplementary general ventilation system in the plant. There are three main
ways for local extraction of fumes-fixed, portable and integral exhaust.
The most important feature of a local system is that the dust and fumes
should move quickly and completely from the source into the hood inlet. The
hoods are used to control dust and fumes which would not naturally enter the
hood.
Additional texts
Read, translate and make up written translation of the texts.
FLASH WELDING
When the edges to be welded are brought together slowly, with voltage
applied, arcing takes place as first points come in contact. This violent arcing
volatilizes metal and increases the distance between the edges at this point with
the result that the arc moves rapidly to other points of lower resistance. Thus,
the arc flits from point to point, increasing in violence with increasing speed of
approach, until uniform flashing occurs over the entire area when pressure
completes the weld.
SPOT WELDING
Spot welding is accomplished by placing overlapping sheets between two
blunt electrodes and passing a very large current from electrode to electrode
through the sheets. When the adjusting metal surfaces are heated to plasticity,
pressure is applied and the sheets are welded together in a spot approximately
equal in size to the end of electrode. The success of this method has, to a large
extend depended on the development of suitable electrode materials. The
exacting demands require high electrical and heat conductivity, fairly high yield
point at elevated temperatures, a considerable degree of hardness and ability to
withstand fairly high temperatures. Some very fine work in the powder
metallurgy of copper and tungsten has resulted in developing the present day
electrode materials.
26
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сказуемое.
1. The computer-controlled Acu Weld automated welding system can
perform a variety of arc welding processes, including GMA, GTA, plasma arc,
microplasma arc, and plasma transferred arc. This provides the flexibility to
produce both one-of-a-kind weldments and large production runs. Changeover
from one process to another takes only minutes, and may involve only welding
head replacement and uploading of the correct program. Programming is in
familiar welding terms and incorporates graphics, menus, prompts and data
entry error checking.
2. A fully automated system performs electrode tip dressing without
interrupting production. This system maintains accurate and consistent
electrode configuration, lowers costs and reduces weld time, claims the
manufacturer. The process is controlled so that dressing ceases when the
desired tip contour is reached.
3. The Weld Computer programmable control system for resistance welding
machines performs on-line machine diagnostics before, during and after each
weld. According to the company, the adaptive-process system diagnoses the
quality of each weld as it is being formed, compensates for changing process
conditions to control weld formation an a cycle-by-cycle basis, and provides
electronic and hard-copy reports of system performance and weld integrity. The
system features an electronic display and provides measurement of such
variables as current, resistance and thermal expansion.
4. The model 831 fume eliminator from stubs weighs 14 ½ kg, its relatively
light weight, ease of handling and positioning, making it ideal for maintenance
and production welding. This new model incorporates an automatic star/stop,
the unit being switched on by striking the arc and off when the arc is broken.
The stop feature can be delayed by 7-20 sec to ensure complete fume
removal. As the motor runs only while welding is in progress, less energy is
used, the motor life is prolonged and noise is reduced. Another automatic
feature is the “filter” indicator, a lamp indicating when the filter needs replacing
this light being activated by a differential pressure gauge constantly monitoring
the pressure before and after the filter. There is a wide range of nozzles which
fits all models, and activated carbon filters and oil film filters are available.
5. A new flux-cored welding wire that is particularly effective on rusty or oily
surfaces is now available from Liquid Carbonic Inc., Scarborough. Designed for
welding mild steel and medium carbon steel in flat and horizontal positions,
Liquid Carbonic 74 is a highly deoxidizing fluxcored wire. It features a stable rac
under all conditions, resulting in virtually no spatter, and produces a flat weld
appearance with almost no ripple. Fume generation level is also low.
27
New products
1. New electroslag technique
The possibility of using a metal powder cored strip electrode and
consumable guide plates for electroslag welding has been examined. It was
found that this technique was capable of stable operation and could produce full
penetration welds. The weld deposition rate was as high as 38 kg/h or 84 Lb/h.
Increased travel speed and decreased specific heat input showed the promise
of this electroslag variant becoming another accepted means of achieving
satisfactory high speed welding. No signs of hot or cold cracking were observed
and substantial grain refinement occurred in the heat-affected zone.
powder cored strip electrode
cold cracking
grain refinement
- порошковый ленточный электрод
- образование холодных трещин
- измельчение зерна
2. Small tube welding head includes wire feeder
The Model R-1 weld head welds small diameter tubes of 0.5 to 1.5 in OD. It
is designed for orbital GTAW of tubes in situations with tight radial and axial
clearances. The weld head is inserted over the tube to be welded and clamped,
requiring less than 10s. A cold wire feeder allows pipe/tube-to-fitting welds to be
made using standard factory beveled fittings. A mechanical arc control device
maintains constant arc gap control device maintains constant arc length on outof-round pipes. The weld heads can be used with any GTAW power source.
3. Underwater plasma cutting
Among the latest developments announced by the East German Manfred
von Ardenne Research Institute are two new plasma-arc cutting machines for
working in underwater conditions. With this type of underwater cutting the
advantages of fine beam plasma operation are combined with the advantages
of water as a medium, which include the inhibition of harmful contamination,
noise reduction, and lessening of ultraviolet radiation. The system for feeding in
gas has been designed to produce a rotational flow/ This rotational gas flow
keeps back water from the edges being cut, which results in a higher quality.
These new machines can also be used for cutting in air if required.
4. Generator offers a range of welding power
The big blue 251D 250-A welding generator features a 100% duty cycle
alternator design with a welding range of 40 to 400A in five separate ranges for
SMAW. While welding, 3 KW/KVA of auxiliary power is available. A lokva threephase auxiliary power kit is optional. This diesel-powered generator features
direct fuel injection providing improved fuel economy, smooth operation, clean
exhaust and quick starts. Optional wire feeders and guns give the machine
capabilities, for GMAW and FCAW. The generators dimensions are 36 ½ x
24 ½ x 35 ¾ in.
alternator
– генератор переменного тока
28
kit
wire feeder
20A-twenty-amperes
FCAW-Flux-cored arc welding
- комплект, набор инструментов
- механизм подачи проволоки
- 20 ампер
- дуговая сварка трубчатым электродом;
дуговая сварка порошковой проволокой
Grammar Exercises
§1. Повторите Passive Voice.
Формула: to be + III форма смыслового глагола
Пассивную конструкцию рекомендуется переводить неопределенноличной или личной формой глагола в действительном залоге, помня о том,
что подлежащее пассивно.
1) The joint faces are heated to a temperature below their melting point.
2) Coalescense is produced by heating to suitable temperatures with or without
the application of pressure and with or without the use of filler metal. 3) Spot
welding is a process in which two metals are held between electrodes passing a
heavy current through the metal to be welded. 4) Butt welding may be applied
for welding pipes, tubing rods, etc. 5) An additive (присадка) is placed into the
flame of the electrical arc. 6) An additive is a metal which is externally applied
to the place of welding and melted to form a weld together with the material of
the work. 7) Soldering is divided into two classifications: soft and hard. 8) The
intense heat required to reduce metal to a liquid state, is created by an electric
arc. 9) The electrode wire is fed vertically into the slag maintaining the end of
the wire at a constant distance from the molten metal pool. 10) An arc is struck
between two tungsten electrodes, and a stream of hydrogen is projected
between them. 11) Submerged arc welding is performed with a continuous
electrode and a granular flux composed with or without deoxidizers and
alloying elements. 12) In automatic welding the arc is guided mechanically
along the joint.
§ 2. Modal verbs
1) Alloy steel must be made by adding some alloying elements. 2) Special alloy
steels can be used for parts requiring great wear resistance. 3) Some metals
have to be melted at very high temperatures. 4) The filler metal must be an
alloy that will produce coalescense. 5) Since both the oxygen and nitrogen of
the atmosphere react with most common metals at elevated temperatures,
consideration must be given to the effect of these gases in the welded metal.
6) The properties of welded sections may be determined by resorting to the
testing methods applied to metals, for instance, tensile, bend and impact tests.
7) All the commonly used metals, as well as most of the exotic metals can be
welded by one or more processes. 8) The liquid metal has to bridge the gap
29
between the parts. 9) The welder must control arc length. 10) The welder
must wear protective clothing including a helmet fitted with a dark glass filter.
11) The source of energy must provide a range of voltage across the arc from
17, which is the minimum for starting an arc, to approximately 45 volts.
§ 3. Infinitive
Прочитайте и переведите предложения с инфинитивом. Помните, что перед
инфинитивом в функции обстоятельства надо вводить слово «чтобы». А инфинитив в
функции определения переводится придаточным определительным предложением с
оттенком будущности и долженствования.
1) Electric resistance welding is a process consisting of heating metals to be
welded to their plastic temperature and then applying mechanical pressure for
achieving a non-detachable joining of the metals. 2) In butt welding the parts to
be welded are pressed together while heat is generated by passing a heavy
current though the area of the joint. 3) Electric arc welding is a process in which
surfaces to be joined are fused together by the heat of an electric arc. 4) The
metals to have been joined included carbon and alloy steels, stainless steel,
cast iron, copper and copper alloys, nickel, nickel alloys and aluminium alloys.
5) Precise heat control is used to permit effective performance of sequential
brazing or soldering operations. 6) Brazing and soldering involve fusion of
joining alloy between the surface of metal parts to be joined. 7) In soldering
low-melting temperature alloys permit joints of limited strength to be made at
temperature below 800oF. 8) A torch should have been used to heat the hard
solder and object to be brazed. 9) Suitable fluxes prevent oxidation of the
joining alloy and metal surface to be joined. 10) The electro-slag welding can
be used to weld plates of various thickness.
§ 4. Paritciple I and II
1. Переведите предложения. в которых причастие выполняет функцию
обстоятельства. Помните, что причастие
I
в этой функции переводится
деепричастием и часто употребляется после союзов if, when, while.
1) After the source of welding heat has been removed, the liquid solidifies, thus
joining or welding the parts together. 2) The electrode wire is fed vertically into
the slag maintaining the end of the wire at a constant distance from the molten
metal pool. 3) A large current is passed through the joint until it has reached
welding temperature, them pressure is applied, upsetting the joint and
completing the weld. 4) It is necessary, when welding thick materials, to bevel
the edges to be joined so they form a “V”. 5) An arc is established between two
tungsten electrodes using alternating current. 6) Leaving the arc, the hydrogen
strikes the metal to be welded, raising its temperature and melting it, using the
additional heat of combination. 7) A high electric current flowing between the
two lightly touching surfaces results in an extreme localization of heat at these
surfaces.
30
2. Причастие II в функции определения переводится причастием страдательного
залога с суффиксами-окончаниями -нный, -емый, -мый, -тый.
1) The history of electric arc welding begins with experiments conducted on
electric arc during the first half of the 19th century. 2) The arc is formed between
the work to be welded and a metal wire called an electrode. 3) In the process of
shielded inert-gas metal-arc welding action is accomplished by the heat
generated by an electric arc established between a consumable or a nonconsumable electrode and the metal to be welded. 4) Filler metal of desired
composition is automatically fed from a reel. 5) Welding speeds may be high,
ranging from 10 to 14 lb of filler metal deposited per hour. 6) The heat liberated
by the junction raises the temperature of the metal. 7) A covered electrode
consists of a rod of metal covered with material serving electrical and
metallurgical purposes. 8) Cored electrodes consist of a tube formed strip and
filled with slagforming, arc stabilizing and alloying materials.
Definition of welding terms
Arc welding – a non-pressure welding process wherein the welding heat is
obtained from an arc either between the base metal and an
electrode, or between two electrodes.
Atomic-hydrogen welding – an alternating current arc welding process wherein
the welding heat is obtained from an arc between two suitable
electrodes in an atmosphere of hydrogen.
Bare electrode – solid metal electrode with no coating. Base metal or parent
metal. The metal to be welded, or cunt.
Brazing
– a group of welding processes wherein the filler metal is a
nonferrous metal or alloy whose melting point is higher than
1000oF, but is lower than that of the metals or alloys to be
joined.
Covered electrode – a metal electrode which has a relatively thick covering
material serving the dual purpose of stabilizing the arc and
improving the properties of the weld metal.
Deposited metal – metal that has been added by a welding process.
Electrode holder – a device used for mechanically holding the electrode and
conducting current to it.
Electrode tip – a replaceable tip of metal on an electrode having the electrical
and physical characteristics required for spot and projection
welding.
Filler metal
– material to be added in making a weld.
Flux
– a fusible material or gas used to dissolve or prevent the
formation of oxides, or other undesirable inclusions formed in
welding.
Fusion
– the melting together of filler metal and base metal, or of base
metal only, which results in coalescence.
31
Fusion welding – a group of processes in which metals are welded together by
bringing them to the molten state at the surfaces to be joined,
with or without the addition of filler metal, without the application
of mechanical pressure.
Gas welding – a non-pressure welding process wherein the welding heat is
obtained from a gas flame.
Metal arc welding – an arc welding process wherein the electrode supplies the
filler metal in the weld.
Pass
– the weld metal deposited by one general progression along the
axis of a weld.
Pressure welding – a group of welding processes wherein the weld is
consummated by pressure.
Rate of deposition – the weight of weld metal deposited in a unit of time.
Resistance welding – a pressure welding process wherein the heat is obtained
from the resistance to the flow of an electric current.
Spot welding – a welding process wherein the fusion is confined to a relatively
small portion of the arc of the lapped parts to be joined.
Weld
– a localized consolidation of metals by a welding process.
Welded joint – a localized union of two or more parts by welding.
Weldment
– an assembly whose component parts are joined by welding.
Weld metal
– the metal resulting from the fusion of the filler or base metals
or both.
Welding rod
– filler metal, in wire or rod form, used in the gas welding
process and those arc welding processes wherein the electrode
does not furnish the metal.
32
Мосталыгина Светлана Евгеньевна
АНГЛИЙСКИЙ ЯЗЫК
Практикум
по развитию навыков чтения и перевода
для студентов 2 курса
технологического факультета специальности
«Оборудование и технология сварочного производства»
Редактор Н.М. Кокина
Подписано к печати
Бумага тип. № 1
Формат 60х80 1/16
Усл.печ.л. 2
Уч. изд. л. 2
Заказ
Тираж 100
Цена свободная
Издательство Курганского государственного университета
640669, г. Курган, ул. Гоголя, 25
Курганский государственный университет, ризограф
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