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UNIT CHOICE OF DESIGN
3
Lead-in
1.
Read these sayings about science and engineering. With the person
next to you, exchange comments, and decide together if there is a
connection between the quotations.
‘Engineering is the art of science of making practical.’
Samuel C. Florman
‘A scientist can discover a new star but he cannot make one.
He would have to ask an engineer to do it for him.’
Gordon L. Glegg
2.
You are going to read a text about choice of design. Before reading
discuss with a partner the meaning of the words given in bold. Explain
the meaning of these words and word combinations.
21
3. Now read the text and find answers to the following questions.
What should be taken into account when choosing the parameters of a
A
machine?
B Name some factors which are evaluated when the final machine version is
chosen.
C What should be done to provide subsequent improvements?
CHOICE OF DESIGN
The designer must choose from a wide array of possibilities to create the design
solution that satisfies the objectives of the people who will use the product. Every
aspect of a product, a device, or a construction, represents such choices. When
choosing the parameters of a machine, its basic scheme and type of construction,
attention must be given to the factor determining its economic efficiency, i. e., high
output, low energy consumption, low maintenance and operation expenditures, a
long life. These decisions, then, are the essence of design.
The designer first had to imagine one or more ways to solve the problem before the
product or device could be put on paper or in computer memory. Generally, the final
machine version is chosen from several ones, which have been carefully evaluated
and compared in all respects of constructional advantages, perfection of kinematics
and force schemes, cost of manufacture, cost of labour, reliability of operation, size,
metal content, weight, assembly-disassembly, inspection, setting and adjustment.
It must be clarified to what degree the original design assures further development,
and what subsequent improvements and modifications can be introduced.
Not always, even after the most careful searching, a successful solution is found,
which completely meets the market demands. Exceptional in constructional practice is
a variant which is a success in all respects. The matter is sometimes not in the lack of
inventiveness, but in the conflicting requirements which are imposed. Under such
circumstances it is necessary to find a compromise solution, waiving some
requirements which are not of prime importance in the given conditions of the machine
application. Often a variant is chosen because it has fewer disadvantages in
comparison with others rather than for its merits.
22
Vocabulary
4. Working in pairs read and translate the following words with the same
roots (see Appendix III Word Formation).
use – useful – usage – useless
technical – technician – technique –
technically
fail – failure
correct – correctly – correction
select – selection – selective – selector
part – partly – partial
continue – continuation – continuous
investigate – investigator – investigation
lead – leader – leading – leadership
accept – acceptable – acceptance
inspect – inspector – inspection
5. Form verbs from the following words and give their Russian
equivalents:
different, productivity, rearrangement, decrease, introduction, generator, reduction,
employment, carefully, development, requirement, suitability, perfection, disassembly,
comparison, variant, acceptable, exceptional
6. Can you say what words/ word come(s) next?
a new technological …, new methods of …, modified …, subsequent …, in the
given …, conflicting …, cost of …, reliable …, economic …, low energy …, growth
of …, thermal …, actual working …, production …, mechanical …, branches of …, heat
…, operational …, steel casting …, continuous …, industrial …, careful …, basic …,
technical …
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7. Fill in the gaps with the suitable words below.
solution construction subsequent expenditures
manufacture economic evaluated energy
1 type of _____________ 5 ______________ consumption
2 ___________ efficiency 6 cost of ___________________
3 operation ___________ 7 _______________ improvement
4 carefully ____________ 8 to find a compromise _________
8. Match the following words (1–10) with their Russian equivalents (a–j).
1 efficiency а решение
2 expenditure b поиск
3 assembly с запрос, спрос
4 adjustment d трата, расход
5 output e регулировка
6 search f набросок, эскиз
7 demand g производительность
8 circumstance h сборка
9 sketch i обстоятельство
10 solution j выпуск
Writing
9. Now look at the list of the words and expressions given in this unit.
Imagine that as a specialist in designing you are given a task to
develop a list of the main points which should be considered making
the right choice of design. Which of them are the most important?
Give your reasons (90–120 words).
24
HOW TO WRITE AN ABSTRACT
ABSTRACT – is a shortened version of a paper written for people who may never
read the full version.
Normally appears at the top of the page in front of the actual paper it outlines.
Informs readers as concisely as possible what is in the article so that one can
decide whether to read it in detail.
ABSTRACT OUTLINE
• Introduction
• Main body
Discussing the characteristic feature of the problem
Methods and materials describing equipment, conditions of experiments
Results
Advantages and drawbacks
• Conclusions
any information that is not in the paper
tables and diagrams
citations from other people’s work
TASK PROCEDURE
Read the text
Underline the main ideas
Write out words and phrases for writing an abstract
Write a draft
NOT
!
Checkup
Rewrite the abstract
Don’t forget the keywords!!!
25
10.
Write an abstract of the text ‘Choice of Design’.
ABSTRACT OUTLINE (example)
The present paper is concerned with……………………………….…
It is the purpose of the paper to give …………………………………
One problem considered in…………………………………………….
The other problem considered in this paper………………………….
Problems of this type have been solved by ………………………….
If conditions are favorable………………………………………………
It is not unlikely…………………………………………………………..
According to………………………………………………………………
It must be stressed (emphasized, underlined) that…..………………
The main drawback is the fact that…………………………………….
To overcome these difficulties………………………. was suggested.
The question should be considered from several points of view …..
For a complete explanation ……….. have to be taken into account.
Consequently,…………………………...…………………………….…
The theoretical and experimental results are found to be……………
To understand the………. better it is necessary that ………..…...….
There is a full agreement (correlation) between the results obtained
and ....................................................................................................
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UNIT
COMPOSITION METHODS
4
Lead-in
1. What does this Chinese proverb about learning mean? Do you agree
with it? How do you like to learn?
I hear and I forget,
I see and I remember,
I do and I understand.
2.
Memorize the Russian interpretation of the following words and word
combinations from the text ‘Composition Methods’. You will come
across them while reading the text.
1 to elaborate several versions – разрабатывать несколько вариантов
2 a relative position – взаимное расположение
3 to draw attention from… – отвлекать внимание от…
4 confuse the logical course – запутывать логический ход
5 common-place alternatives – стереотипы
6 be accompanied by calculations – сопровождаться расчетами
7 strength and rigidity – прочность и жесткость
8 key and spline connections – шпоночные и шлицевые соединения
9 diameter of a thread – диаметр резьбы
10 a concentric fitting surface – соосная посадочная поверхность
11 to a larger extent – в большей степени
12 to take into account – брать в расчет
13 adjacent parts – смежные детали
14 drive shaft – ведущий вал
15 corrosion protection – защита от коррозии
16 wear resistance – износостойкость
17 forced conditions – форсированные режимы эксплуатации
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3.
Complete the text ‘Composition methods’ by putting one part of a sentence
(A–H) in each space (1–8).
A.
B.
C.
D.
E.
F.
G.
H.
Generally composition has two stages: (1)………….. At the stage of draft composition the
main arrangements and a general design of the given unit are elaborated (sometimes
several versions). After discussing the draft a working scheme is composed which defines
all feasible versions
draft and operational
selection of rational kinematics
the initial material for further designing
main design components
methods for improving the machine durability
the basis of standard dimensions
maximum unification of standard elements
COMPOSITION METHODS
more accurately the design of the unit and serves as (2) …………..
It is necessary to begin the composition with the solution of the main problems of designing,
i. e., (3) …………… and power schemes, proper sizes and shapes of parts and
determination of the most suitable relative positions. At this stage of designing any attempt
to describe the parts completely is not only useless, but harmful, as it draws attention from
the main problems of composition and confuses the logical course of designing.
Another fundamental rule of composition is parallel development of several design
alternatives, the analysis and selection of the best version. The most dangerous thing
at the above stage is to give in to psychological inertia and choose a common-place
alternative. The designer should analyse carefully (4) ……….. and choose the most
suitable one for the given conditions. This requires a lot of work and the problem is
sometimes solved only after long investigations.
Composition must always be accompanied by calculations. (5)………….. should be
calculated not only for strength but also for rigidity as well.
28
Another crucial point of correct designing implies permanent attention to the problems
p
of manufacture, for instance, a component should be given a technologically rational
shape from the very beginning of designing.
Composition must be carried out on (6)………….. (fitting diameters, the size of key and
spline connections, diameters of threads, etc). This is particularly important when
composing units with several concentric fitting surfaces or with gradation of stepped
parts, as their shape, to a large extent, depends on the gradation of the diameter.
At the same time, (7)………….. should be sought for. The chosen elements for the main parts
and units should be utilized in all the adjacent parts of the design as much as possible.
In the process of composition a designer must take into account all the conditions that
define the machine operability. The systems of lubrication and cooling, convenient
assembly and disassembly, connection of adjacent parts (drive shafts, piping, electric
wires, etc) should be developed. Convenient maintenance, inspection and adjustment
of the mechanism should be provided. The right choice of materials for the main
components, (8)………….. and wear resistance of rubbing surfaces, as well as
methods of corrosion protection should be developed. In addition to all the points
mentioned above, the designer is supposed to investigate and determine the limits of
the machine when it operates under forced conditions.
Vocabulary
4. Read the text again and find the synonyms to the following words.
attentively –
choice –
basic –
to demand –
steps –
possible –
work out –
approximate –
usually –
recisely –
research –
mating parts –
29
5.
Give the Russian equivalents of the following word-combinations. The
text ‘Composition Methods’ will help you. Then use 4–5 expressions
in sentences of your own.
1 a commonplace solution
13 simplicity of maintenance
2 instruments for testing and
measuring
3 be accompanied by
4 reduction in the quality of work
5 improved suitability
6 inspection and adjustment
7 corrosion protection
8 the present-day mechanical
engineering
9 determine the limits
10 the basis of designing
11 the cost of a machine
12 to arrange the parts
6.
Pick out the Russian equivalent from column В (1–14) which is close
14 convenience of assembly
15 to meet the industrial requirements
16 an attractive finish
17 stability of readings
18 engine efficiency
19 technical assignment
20 the required parameters
21 a wide range of operations
22 reliability and durability
23 feasible solutions
24 investigate the object
25 make changes to the draft
26 versatile machines
in meaning to the word in column A (a–n):
A В
1 because of
2 as well as
3 in this way
4 in addition to
5 once
6 by means of
7 not yet
8 although
9 irrespective of
10 as such
11 both . . . and
12 in many respects
13 in particular
14 in general
a пока еще не
b таким образом
c однажды; когда
d также как и
e из-за
f кроме того
g посредством, с помощью
h хотя
i как... так и…
j независимо (от чего-л.)
k по существу; как таковой
l во многих отношениях
m в общем
n в особенности
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