Figure. Horizontal Milling Machine

1— base;2 —column;3— overarm;4 —mandrel support;5 —spindle;

6—table; 7— saddle;8—feed shaft;9—knee;10 —table traversing screw

The strict distinction between the operations ofdrilling and boring is that the firstinitiates a hole, while the secondenlarges one already existing. Reaming is the operation enlarging a machined hole toaccurate size with asmooth finish. The sawing of materials is an important operation too.

Broaching is a machining method in which one or more cutters (broaches) with aseries of teeth arepushed orpulled across asurface to machine that part to the desiredshape. The broach has a number of successive teeth of increasing size which cut in a fixed path. Grinding is the only method of cutting such materials ashardened steel. Grinding is performedwith a rotating abrasivewheel. Cylindrical,internal, surface and centreless grinders are common types.

Exercise 1.1. Find the Russian equivalents for the following word combinations:

the machining of metals; lie at the basis; are reflected developments; abrasive materials; the strict distinction; enlarging a hole; to accurate

size; the sawing of materials; a machining method; with a series of teeth; are pulled across a surface; the desired shape; to machine a part; a hardened steel; an abrasive wheel; tool steel.

лежат в основе; метод обработки; тянутся через поверхность; отражены достижения; абразивное колесо; пиление материалов; с серией зубьев; желаемая форма; закаленная сталь; инструмен­тальная сталь; обрабатывать деталь; до точного размера; увеличи­вающее отверстие; точное отличие; обработка металлов; шлифу­ющие материалы.

Exercise 1.2. Answer the questions:

1. What is the machining of metals?

2. What machining operations do you know?

3. What lies at the basis of all modern industrial production?

4. What are the main hard materials used in machining as cutting tools?

5. What is the difference between drilling and boring?

6. What is reaming?

7. What is broaching?

8. What is grinding used for?

9. What is grinding performed with?

Exercise 1.3. Complete the sentences choosing one of the appropriate variants:

1. The machining processes have been developed since the development of...

2. Diamonds, carbon, tool steel, high-speed steel, stellite carbides, and abrasive materials are...

3. The strict distinction between the operations of... is that the first initiates a hole.

4. Broaching is a ... in which cutters are pushed or pulled across a ... to machine the workpiece to the desired shape.

5. Grinding is performed with а...

6. Machining operations ... of all modern industrial production.

7. ... is the operation which enlarges a hole to accurate size with a smooth finish.

machining method ... surface; the steam engine; lie at the basis;

reaming; drilling and boring; hard materials; rotating abrasive wheel.

Exercise 1.4. Translate into English:

1. В процессе обработки металлов удаляется стружка с детали.

2. Обработка металлов лежит в основе производства.

3. В проектировании машин отражаются все достижения ма­шиностроения.

4. Отличие между сверлением и расточкой состоит в том, что при сверлении отверстие просверливается, а затем увели­чивается при помощи расточки.

5. Развертывание увеличивает отверстие до нужного размера.

6. Протяжка придает детали необходимую форму.

7. Шлифовка выполняется при помощи вращения абразив­ного колеса.

11. Text В TRANSMISSION MACHINE PARTS

Memorize the pronunciation of the following words:

shaft [fa:f t] —вал,ствол

coupling [' kApliij] —муфта,сцепление

permanent ['рэ: msnantj —постоянный

clutch [klAtJ] —защелка,муфтаповорота

to engage [in' geid3] —зацеплять

power [' раиэ] — мощность, сила, энергия

to intersect [, inta'sekt] —пересекаться,скрещиваться

angle [' asngl] — угол

driving [' draiviijJ — проходка, передача

to rotate [rou' teit] — вращаться

stationary [' steifnari] — неподвижный, стационарный friction [' f rikjh] — трение

slippage [' slipid3| — проскальзывание, буксование

spur [spa: ] — шпора

gear [gia] — шестерня, редуктор

helix ['hi : liks] — спираль, винтообразная линия

skew [skju:] — скошенный

wheel [wi: 1] — колесо

fluctuation [, flAktju'ei/n] — колебание, отклонение flywheel [' flaiwi : 1] — маховое колесо, маховик to smooth [smu: 3] — делать ровным (гладким), шлифовать cam [ksem] — кулачок, копир

reciprocating [ri' siprakeitiij] — возвратно-поступательный oscillation [,osi'leifn] — качание, колебание, вибрация crank [' krseqk] — кривошип, коленчатый рычаг torque [to: k] — скручивающее устройство

Word combinations for connected reading:

are referred to (as) — называют

gives rise to — создает, вызывает

jaw clutch — кулачковая муфта

plate clutch — дисковая муфта

spur gear — дисковое колесо

helical gear — геликоидальное зубчатое колесо

herringbone gear — шевронное зубчатое колесо

bevel gear — коническое зубчатое колесо

worm gear — червячная передача

crown wheel — храповое колесо

TEXT

It is often necessary to join sections of long transmission shafts withcouplings. These couplings are also required to connect the shaft of driving machine to a separately built driven unit.

Permanent couplingsare referred to simply as couplings, whileclutches may be readilyengaged or disengaged. Universal joints permit the positive transmission ofpower between shaftsintersecting at a comparatively largeangle. When thedriving machine or machine member must rotate continuously and thedriven member must be arranged torotate or remainstationary as desired, a clutch must be used. There are many types of clutches. The simplest clutch is thejaw clutch. It is widely used in automobile transmission. Other types of clutches are:plate friction clutches, cone clutches, and automatic clutch couplings.

Gears are employed to obtain positive driving action without slippage. There are many types of gears.Spur gears are most commonly used to connect parralel shafts and make them rotate in opposite directions.Helical gears differ from spur gears in that their teeth are of helical or screw form. Theherringbone gear is equivalent to two helical gears, one having a right-hand and other a left-handhelix. Spiral gears are cylindrical gears with helical teeth. They are used to connectskew shafts. Terms used with gear teeth are shown in figure.

Crown wheels, bevel gears, andworm gears must also be mentioned. The worm gears are used to connect skew shafts. Theflywheel is

Circular thicknesi 9

Figure. Terms Used with Gear Teeth

Outside or odstndum txrcb

Pitch / clnle—y/X

Sase circle'

employed to smooth out the speedfluctuations. The eccentric and thecam serve to produce some form ofreciprocating oroscillating motion. Thecrank mechanism is employed to change the reciprocating motion to the rotary one, whichgives rise to torque.

Exercise 1.1. Find the Russian equivalents for the following word combinations:

to join shafts with couplings; joints permit; at a comparatively large angle; to remain stationary; to obtain the driving without slippage; to connect parallel shafts; to rotate in opposite directions; differ from spur gears; teeth are of helical or screw form; to smooth out the speed fluctuations; reciprocating and oscillating motion; is employed to change.

достичь передачи без проскальзывания; свести на нет колеба­ния скорости; соединить валы с помощью сцепления; стыки по­зволяют; соединить параллельные валы; вращаться в противопо­ложных направлениях; под сравнительно большим углом; зубья гелиоцентрической или винтовой формы; применяется, чтобы из­менить; отличаются от цилиндрических колес; возвратно-посту­пательное и колебательное движение; оставаться неподвижной.

Exercise 1.2. Answer the questions:

1. What is the basic difference between couplings and clutches?

2. What types of gears do you know?

3. What is the function of gears?

4. What purpose is the flywheel used for?

5. What is the function of the crank mechanism?

Exercise 1.3. Find the true statements from the text:

1. Permanent couplings are referred to as clutches;

2. It is necessary to join sections of long transmission shafts with clutches;

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3. The simplest clutch is the plate clutch;

4. Gears are used to obtain positive driving action without slippage;

5. Helical gears are used to connect parralel shafts;

6. The herringbone gear is opposite to two helical gears;

7. Helical gears differ from spur gears in that teeth are of skew form;

8. Spiral gears are used to join bevel gears;

9. The cam serves to produce some form of reciprocating or oscillating motion.

Exercise 1.4. Complete the statements using the appropriate word combinations:

The couplings are required to connect... to a separately built driven unit.

When the driving machine must rotate continuously and the driven member must be arranged to ... as desired, a ... must be used.

Gears are employed ... positive driving action without slippage. The flywheel is employed ... the speed fluctuations.

The worm gears are used to connect...

to smooth out; skew shafts; the shaft of driving machine; to obtain; rotate or remain stationary ... clutch.

Exercise 1.5. Translate into English:

Необходимо соединить валы длинной передачи при помощи сцепления.

Муфта поворота используется для непрерывного вращения детали.

Кулачковая муфта используется в автомобильной трансмиссии.

Цилиндрические колеса используются для вращения парал­лельных валов в противоположных направлениях.

Геликоидальное зубчатое колесо отличается от цилиндричес­кого колеса по форме зубьев.

Червячная передача соединяет скошенные валы.

Шевронное зубчатое колесо равно по функциям двум гели­коидальным.

Коленчатый рычаг преобразовывает поступательное движе­ние во вращательное.

12. Text В MACHINE PART FASTENING

Memorize the pronunciation of the following words:

to fasten [' f a: sn] — прикреплять

welding ['weldiij] — сварка

riveting ['rivitirj] — заклепка

thread [Gred] — резьба

joints [d30int] — соединение, стык

bolting (' boultit}] — скрепление болтами

keying [' ki : ii]| — шпонка

to assemble [э' sembl] — собирать

member [' memba] — деталь, элемент конструкции

permanent [' рэ: manant | — постоянный

destruction [dis'trAkJn] — разрушение, уничтожение

to insert [in' sa: t] — вставлять

to punch [' pAntJ] — пробивать отверстие, штамповать отверстие

hole [houl] — отверстие

soldering [' soldarir)] — мягкая пайка

brazing [ 'breizii]] — твердая пайка

fit [fit] — посадка

pressure [ 'prejaj — давление, напряжение fusion ['fju-.зэп] — плавкий, плавление screw [skru: ] — винт

unit [' ju:nit] — единица, агрегат, установка shipping ['Jipii]] — погрузка, перевозка pitch [pitj] — шаг (резьбы); угол наклона lead [li: d] — ход, шаг (винта) diameter [dai'semita] — диаметр

designate ['dezigneit] — характеризовать; определять through [9ru: ] — через, сквозь nut [nAt] — гайка, муфта

accessible [eek'sesobl] — доступный, податливый flange [f leind3] — гребень, фланец cap fkasp] — колпак, верхушка

mating ['meitiq] — сопряженный, парный (о детали)

loose [lu: z] — свободный, холостой

washer ['wo/э] — шайба, прокладка

pin [pin] — шпилька, штифт, чета

locking ['lokig] — блокировка

knuckle ['плк1] — шарнир, цапфа, коготь

rod [rod] — прут, палка

flexibility [' fleksa'biliti] — гибкость

Word combinations for connected reading:

minor diameter — внутренний диаметр locking device — блокирующее устройство fight fit — неподвижная посадка

TEXT

Some forms of fastening, such aswelding, riveting, directthreaded joints, bolting orkeying, must be used inassembling the individualmembers to form a complete machine or structure.

Riveting makes a permanent joint that cannot be disassembled withoutdestruction of the rivets. In making up this joint, the rivet isinserted in apunched or drilledhole and the second head is formed by a rivet set, air hammers, and air- or hydraulic-pressure machines. Welding,soldering, brazing and fightfits belong to permanent joints. Welding is the method of joining metals bypressure, after heating them to a plastic or semimolten state, or of joining metals byfusion alone.

Threaded bolts and screws are used to hold together machine parts that must be readily disassembled, and parts of large machines that must be built in smallunits for ease in manufacturing, assembling orshipping. The forms of common screw threads are shown in the figure.

The following data of every screw are very important: the pitch, thelead, majordiameter (nominal diameter), and minor diameter (root diameter). A thread may be a left-hand or a right-hand one. Bolt sizes aredesignated by the outside diameter of the thread and by the length under the head.Through bolts are used where both the head andnut can be madeaccessible by the use offlange connections.Cap screws have no nuts; the screw passes through a clearance hole in one member and threads into themating member. To prevent nuts from workingloose, specialwashers, pins, and nuts are used aslocking devices.

Knuckle joints are used to connect tworods or bars when a small amount offlexibility or movement is necessary.

Exercise 1.1. Find the Russian equivalents for the following word combinations:

in assembling the individual members; without destruction of the rivets; is inserted in a drilled hole; joining metals by pressure; are designated by the outside diameter of the thread; use of flange connections.

без разрушения заклепок; использование гребневых соеди­нений; характеризуются внешним диаметром резьбы; в сборке отдельных деталей; вставляется в просверленное отверстие; со­единение металлов под давлением.

Exercise 1.2. Answer the questions:

1. What forms of fastening can for the assembling of a machine or structure be used?

2. What can you say about riveting?

3. What kinds of welding do you know?

4. When are bolts and screws used to?

5. What are the most important data of every day screw?

6. What are bolt sizes designed by?

7. When are knuckle joints used?

Exercise 1.3. Find the wrong statements and correct them:

1. Some forms of fastening are used in disassembling the individual members.

2. Riveting needs in destruction of the rivets.

3. Soldering is the method of joining metals by pressure.

4. Knuckle joints are used to connect two rods or bars.

5. Bolt sizes are designated by the inside thread.

6. The screw passes through a hole in one member and threads into the mating member.

7. In making up the joint, the rivet is retrieved from a drilled hole.

Exercise 1.4. Translate into English:

1. Постоянный стык делается с помощью клепки.

2. Крепления используются в сборке отдельных деталей.

3. Винт проходит сквозь отверстие в детали.

4. Гайки используются как блокирующие устройства.

5. Болты с резьбой и винты используются для соединения деталей.

6. Бруски соединяются шарнирными стыками.

7. Сварка соединяет металлы посредством плавки.

12. Text В

BEARINGS