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Файл:Materials Processing Technology Part 2. Coursebook
.pdf
submerged arc
welding
a welding process where the workpieces are joined by
means of electricity
gas tungsten arc
welding
relies on the heat of a flame caused by the reaction
between a fuel gas and oxygen
electric resistance
welding
a fabrication process that joins materials by causing
coalescence. through melting the workpieces and adding
a filler material
plasma arc welding
starts at the left hand side of the joint and progresses
towards the right
productive welding power join similar
advantages
performance lifetime equipment microstructure
joint
cracks energy mechanical automated welds
impact heat
_____3 Complete the text about laser beam welding by choosing a word
from the box.
Laser beam welding is a welding technique used to _______multiple pieces
of metal through the use of a laser. The beam provides a concentrated
______source, which allows for narrow, deep ______ and high _______rates.
The welding process may lead to drastic changes in the ________ with
accompanying effects on the ________ properties and on the performance of the
_______. Laser welded joints may contain defects in the form of _______ in the
narrow weld area. The size and location of such cracks directly affect the joint
__________ and the _________ of a structure. Nevertheless, laser beam
welding has a number of _________ over conventional processes. Despite the
high investment cost of laser welding _________, it is expected that laser beam
welding will have a great _______ on fabrication and manufacturing industries.
Laser beam welding and electron beam welding are quite _______
processes, differing most notably in their source of ________. Both have a very
high _______ density, making deep weld penetration possible. Both processes
are extremely fast, and are easily _________ , making them highly __________.
_____ 4 Use the possibilities of Quizlet to develop and train your vocabulary:
a) on the topic ‘Metalworking processes and tools’ at
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https://quizlet.com/384399422/metalworking-processes-and-tools-flash-
STUDY SKILL Noun Compounds (1)
Noun compounds consist of two or more nouns placed together
to represent specific items or substances. They represent an ultimate
reduction of an adjective clause:
The machinist produced a worm gear. (noun compound) > The
machinist produced a gear shaped like a worm. (reduced adjective
clause)
Engineers installed a water purification system. (noun compound)
>Engineers installed a system for the purification of water.
(reduced adjective clause)
Noun compounds are used frequently in scientific writing
because they express a great deal of information with a few words.
They are like reminders of once-learned definition.
1. test data
a. data from a test
b. a test of current data
2. camera
platform
a. a platform for a camera
b. a camera that sits on a platform
3. glass fiber
a. a kind of glass in the form of fibers
b. b. a kind of fiber made from glass
4. voltage
regulation
a. normal voltage as prescribed by
regulations
b. regulation of voltage
5. radar scan
a. a kind of radar that scans
b. b. a scan performed by radar
6. carrier lipid
a. a lipid that carries peptide units
b. b. a carrier for lipids
7. silicon crystal
a. silicon in the form of a crystal
b. a crystal of silicon
cards/?new
b) on the topic ‘Welding operations’ at
https://quizlet.com/386420794/welding-operations-flash-cards/?new
c) on the topic ‘Laser beam welding’ at
https://quizlet.com/387490439/laser-beam-welding-flash-cards/?new
d) on the topic ‘Metal-joining processes’ at https://quizlet.com/386829955/metaljoining-processes-flash-cards/?new
_____1 Choose the correct definition for the noun compound on the left.
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8. surface metal
a. metal at the surface
b. the surface of a metal
9. process
research
a. research into the nature of a process
b. the process of doing research
10. junction diode
a. a junction where two or more diodes
come together
b. a diode formed from the junction of
p- and n-type semiconductors
STUDY SKILL Noun Compounds (2)
With the exception of the first example, which requires adjectival
modification, noun compounds can be classified in the following
way.
(NOTE that formal definitions can be classified by the kind of
question that the defining adjective clause answers about the word
being defined).
1. Properties (What are its characteristics?): [requires an
adjective structure, e.g. strong wire ]
2. Material (What is it composed of?): copper wire (wire that is
made of copper)
3. Operation (How does it work?): friction brake (a brake that
works by means of friction)
4. Purpose (What does it do?): air filter (a filter for cleaning air)
5. Location (Where is it used/found?): field mouse (a mouse that
lives in fields)
6. Time (When is it used?): night hawk (a hawk that hunts at
night)
7. Shape/form (What does it resemble?): worm gear (a gear that
is shaped like a worm)
8. Inventor/Professional user (Who discovered/uses it?) : Bunsen
burner (a burner that was invented by Robert Bunsen)
______ 2 Classify the following noun compounds according to the list below.
Then define the noun compound in terms of the classification.
1. Properties 5. Location
2. Material 6. Time
3. Operation 7. Shape/form
4. Purpose 8. Inventor/Professional engagement
Example: ---- gear pump
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3. Gear pump: a pump that operates by means of gears
STUDY SKILL Noun Compounds (3)
Longer noun compounds are used in more specialized areas.
They can generally be interpreted by reading the compound in
reverse:
air quality program = a program for maintaining the quality of
the air;
acquired immune deficiency syndrome (AIDS) = a syndrome
based on a deficiency of the immune system that is acquired, not
inherited
Longer noun compounds cannot always be read directly in
reverse because certain words have a particularly close
relationship. These closely related words are not interpreted in
reverse order:
acid nitrate deposition = the deposition of acid nitrates
city water chemical contamination monitoring program =
program for monitoring the chemical contamination of city water
NOTE: In scientific writing, we must be very careful only to use
those noun compounds which are acceptable in scientific
language.
Problems arise if we try to make up new ones, especially if they
contain three or more nouns.
1. ____ long-wire antenna 11. ___ weed killer
2. ____ passenger ship 12. ___ Bernouilli equation
3. ____ computer industry 13. ___ morning sickness
4. ____ furnace gases 14. ___ ceramic insulator
5. ____ steam engine 15. ___ air compressor
6. ____ water table 16. ___ needle-nose pliers
7. ____ annual report 17. ___ gasoline engine
8. ____ manganese nodule 18. ___ vent microbes
9. ____ vacuum cleaner 19. ___ day shift
10. ___ dock crane 20. ___ blood sample
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_____4 Change the words in italics into noun compounds.
STUDY SKILL The passive voice (1)
The passive voice is used when it is not important who or what does
an action. It is formed by the verb to be in the correct tense + the
past participle.
The base metal is cooled to join the work pieces together.
A preliminary analysis was produced.
NOTE An academic text will usually have a mixture of active and
passive sentences.
Example: The vent for air should be open.
Answer: The air vent should be open.
1. Oil from the peel of citrus fruits acts as a pesticide.
2. Neurosurgeons are developing a map of the system of nerves in humans.
3. A soil fumigant made from ethylene dibromide has been recently tested.
4. Researchers have located the site for the binding of RNA.
5. The material for insulation which is made from formaldehyde burned
rapidly, releasing toxic fumes.
6. The facility for electric power which is made of concrete was seriously
damaged by the earthquake.
7. The company announced that it would end its program of research into
superconducting computers.
8. The radiation from microwaves that forms a background resulting from
the “big bang” has been determined to be 3° Kelvin.
9. Some stars fueled by a cycle of thermonuclear burning involving
carbon, nitrogen, and oxygen.
_____ 5 Change the phrases in italics into noun compounds.
A reduction in noise of approximately 6 d8 could be effected by replacing the
existing assembly containing a blower fan with a blower, Model TL-1,
manufactured by Quietaire Corporation of Detroit, and by lining the ducts with
Agrafoam, a new product that performs soundproofing developed by the industry
that makes automobiles in West Germany. A further reduction of 1.5 dB could be
achieved by replacing the tiles on the floor made by vynil with indoor/outdoor
carpet, a practice that has been successful in centers for control of traffic in the air.
DEVELOPING GRAMMAR AND WRITING SKILLS
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_____1 In the following sentences put the verb in brackets in the correct
STUDY SKILL Passive vs. Active voice: Inanimate subjects with active
verbs (2)
Inanimate subjects often occur with active rather than passive verb in
scientific English. In this way fewer words are used to express an idea.
form, active or passive.
1. In open-die forging, a hammer strikes and deforms the workpiece, which ____
(to place) on a stationary anvil.
2. Sheet metal forging processes are those in which force _____ (to apply) to a
piece of sheet metal to modify its geometry.
3. Excess metal ______ (to squeeze) out of the die cavities, forming what is
referred to as the flash.
4. As the current flows between the electrode and the workpiece the tip of the
electrode _______(to melt) and _______(to fall) onto the workpiece.
5. The weld _______(to start) at the left hand side of the joint and _______ (to
progress) toward the right.
6. Roll forming is a metal forming process in which sheet metal _______ (to
shape) through a series of bending operations.
7. Creep extended over a long time finally ______ (to lead) to the rupture of the
material.
8. Deep drawing is a metal forming process in which sheet metal ________ (to
stretch) into the desired shape.
9. Stretch forming ________(to perform) on a stretch press, in which a piece of
sheet metal _______ (to grip) along its edges by gripping jaws.
10. Plasma arc welding ________(to use) a tungsten electrode and plasma gas to
make the arc.
11. A special variable polarity PAW machine ________ (to develop) for welding
aluminum, where the presence of aluminum oxide films ________(to prevent) a
keyhole from being established.
12. The tooling is a stretch form block, which is a solid contoured piece against
which the sheet metal ______ (to press).
13. Under tension, a material usually ________ (to stretch), returning to its
original length if the force does not exceed the material’s elastic limit.
14. Composite materials ________ (to produce) by the hot compaction methods,
which are better in their properties, especially in durability.
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Look at the examples:
a. The colour of the solution is changed by adding acid.
b. With acid, the colour of the solution changes.
c. We change the colour of the solution by means of acid.
d. If we add acid, the colour of the solution changes.
e. Because acid is present, the colour of the solution is changed.
These are all correct sentences in English, but they are wordy and
indirect.
A better way to write the above sentences is:
Acid changes the colour of the solution.
Notice that the subject of the sentence (acid) is not a person but an
agent.
In many languages, it is impossible to use an inanimate subject in this
way.
However, scientific English prefers the use of inanimate subjects and
active voice for clarity and conciseness. Inanimate subjects show a
cause and effect relationship:
Inanimate subject +Active
verb
Cause
Effect
1.Gravity keeps the moon in
its orbit.
2.The clouds are moving to
the east.
3.The carbon14 dating
method determined the age
of the sample.
gravity
(wind, earth
rotation)
C
14
method
moon in orbit
clouds move
age of the
sample
determined
______2 Underline the inanimate subjects and active verbs contained in the
paragraphs below.
1. The outer surfaces of large meteorites melt rapidly. After passing air streams
have swept this liquid rock away, a new cool layer of material is exposed. The
molten liquid creates the blazing trail which is seen from the earth.
2. Although man has climbed the highest mountain and probed the depths of the
ocean, no one has found sufficient evidence to identify the famous Loch Ness
monster in Scotland. However, some researchers believe that the “monster” is
simply pine logs which have fallen into the deep lakes and decayed, producing
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bubbles which are sealed by the pine resin. Eventually, the logs become buoyant,
and they float to the surface.
3. Not only numbers but characters are coded in binary when they are transmitted
to the computer. The machine gives a list of equivalent expressions to represent
these symbols. The central processing unit is designed to recognize these binary
numbers. The programmer, however, must organize and separate the information
the computer needs and the instructions it must execute in order to obtain
accurate results for the program.
_____3 Fill the blanks with an inanimate subject and an active verb derived
from the information in the first sentence.
Example: In orange juice, vitamin C is contained.
Answer: Orange juice contains vitamin C.
1. Because of the El Niño current, many fish were killed.
___________________________________ many fish.
2. In chlorophyll, magnesium is contained.
________________________________ magnesium.
3. With the “big bang” theory, the origin of the universe is described.
________________________________________ the origin of the universe.
4. The patient’s heartbeat was monitored by the machine.
_______________________________________the patient’s heart beat.
5. A gas pipeline connection is made between the oil fields and the seaport.
______________________________________ the oil fields and the seaport.
6. Electrical engineers measure the voltage in a system with a volt meter.
________________________________________ the voltage in a system.
7. The I-beam has a resistance to compression and tension.
_________________________________ compression and tension.
8. The heat of the sun causes ocean water to evaporate, forming clouds.
__________________________________ ocean water, forming clouds.
9. The chain reaction in a nuclear power plant is shown in Figure 1.
______________________________the chain reaction in a nuclear power
plant.
______4 Change the following causes and effects into sentences with
inanimate subjects and active verbs.
Example: catalyst is present → reaction rate increased
Answer: The catalyst increases the reaction rate.
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1. glaciers existed → many valleys were changed from a V-shape to a U-shape.
STUDY SKILL Passive structures with by-agents (3)
Approximately eighty percent of all passive sentences in English do not
include the active subject. In the remaining twenty percent, many active
subjects are included in a by-phrase.
By and the agent or by-agents (the subject of the active sentence) are
omitted because the agent is obvious or not necessary.
Men’s ties are usually made of silk or polyester by manufacturers.
An important reason for using the passive verb form is to keep the topic
noun phrases in the subject position, another form of focus. For
example:
The chemical engineer uses heat exchangers, Venturi meters, and
other
devices to control the temperature and pressure of fluids. → Heat
exchangers
are used (by chemical engineers) to control the temperature of a
fluid.
In other words, the main topic of a paragraph is usually put in the
“strong” subject position.
2. penicillin is effective → dangerous bacteria are destroyed.
3. a seismometer is a machine → it is used to measure earthquakes.
4. welding is used → sometimes metallurgical changes in materials are produced.
5. nitrogen is deficient → leaves become yellowed and plants’ growth is stunted.
6. use fire to polish the sharp edges of a new glass tube
(Fire polishing …) → the edges are softened by this process.
7. a solution is hypertonic → blood cell shrinkage occurs.
8. force acts on a rigid body → a reaction force in the opposite direction is
generated.
______5 Complete the following sentences with the by-agent is necessary.
Example: Poisons are removed from the blood (the liver)
Answer: Poisons are removed from the blood by the liver.
1. Silk is produced. (silk worms)
2. Gunpowder is used in making weapons. (the weapon industry)
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3. The Golden Gate Bridge was built in 1937. (workers)
4. Some animals use trees to build dams. (beavers)
5. Honey is made to feed their young. (bees)
6. In plants, water is absorbed. (the roots)
7. The doctor requested that an x-ray of the patient be taken. (nurse)
8. The structure of the DNA molecule was discovered in 1953. (scientists)
SPEAKING Preparing a presentation
____1 Give a 5-10 minute presentation to the members of your group. Possible
topics are as follows:
a) History of ferrous metallurgy;
b) Sheet forming processes: Sheet metal;
c) Robot welding;
d) Glassblowing and plastic welding.
To find information on the topic “History of ferrous metallurgy”, use the
following website:
- Wikipedia at https://en.wikipedia.org/wiki/Ferrous_metallurgy;
To find information for the presentation on the topic “Sheet metal”, go to the
following website:
- Wikipedia at https://en.wikipedia.org/wiki/Sheet_metal;
To find information for the presentation on the topic “Robot welding”, go to the
following website:
- Howling Pixel at https://howlingpixel.com/i-en/Robot_welding;
- Wikipedia at https://en.wikipedia.org/wiki/Robot_welding.
To find information on the topic “Glassblowing and plastic welding”, use the
following website
- Wikipedia at https://en.wikipedia.org/wiki/Glassblowing
and https://en.wikipedia.org/wiki/Welding#Plastic_welding.
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