5. Use the words with the same root in situations.

case – casing, join – joint, design – designing – designed – designer, prevent – preventive – prevention.

6. Group the synonyms and use them in situations.

run, act, result, made of, apply, link, casing, fast, use, stiff, fasten, carry, consist of, join, quick, solid, couple, rigid, composed of, operate, attach, cause, bear, make, follow, rapid, housing, utilize, cover, connect.

7. Complete the words with the negative prefixes: semi-, dis-, un-, de-, in-, mis-, over.

1. There are permanent and ____-permanent joints. What has the form of a ____-circule? 2. Overloaded machine component may be ____ -formed.

3. ____-connectable joints are widely used. 4. ____-use of a machine part will result in its breaking. 5. There is nothing ____-usual in mechanics. 6. Machine components will be ____-shaped if they do not resist stresses. 7. What ____-directional quantities do you know? 8.____ -allignment may occur. 9.____ -running clutches may be of a jaw type.

8. Transform the subbordinate clauses into the Absolute Nominal Participle Construction.

Model 1.The assembling finished, the conveyer was put into operation. Model 2. We discussed our problems, the computer working.

1. As the problem had been solved, the engineers began a new

experiment. 2. When the plan had been discussed, the meeting was over. 3. Since this law had been discovered, there are a lot of new possibilities. 4.After the engineer had come, the experiment began. 5. Because the strain of the body exceedes a certain value, the body does not recover completely. 6. A body is under hydrostatic stress, so the pressure upon it on all sides is the same. 7. When a body is under tensile stress, the forces acting upon it tend to increase its length. 8. An external force is acting, and the body changes its state of rest to a state of motion. 9. The elastic properties of various materials are different, but the ratio of stress to strain is always the same for a given material within the elastic limit. 10. When the destorting force is removed, elastic bodies exhibit the property of recovering to their original state.

9. Discuss the advantages and disadvantages of different types of couplings.

Text 2

1. Scan the text to receive information. Clutches a clutch permits easy and quick connection and disconnection of two

shafts. Factors which must be taken into consideration in deciding what type of clutch is to be used are: torque, rotation, speed, available space and frequency of operation. The object of friction clutches is to con­nect a stationary machine part to a rotating part, to bring it up to speed and to transmit the required power with a minimum of slippage.A clutch is also used instead of a key to connect the shaft with a revolving part, such as a

pulley or a gear. Friction pitches may be divided into two main groups

according to the direction of the acting force: axial clutches and radial

clutches.

Fig. 17. a clutch.

Classification of Clutches. Friction clutches may be divided into two main groups according to the direction of the acting force: axial

clutches and radial ones.

Axial clutches are those which have the contact pressure applied in the direction parallel to the axis of rotation. Axial clut­ches, in turn, can be subdivided into: a) cone clutches, b) disc clutches and c) combined cone and disc clutches. In radial clutches the contact pressure is applied

upon a rim in a radial direction. These clutches may be subdivided into band clutches and block clutches, also into ex­ternal, internal and combined internal and external clutches.

Vocabulary

transmit torque передавати обертальний момент

rotate, revolve обертатися

frequency частота

friction clutch фрикційна муфта

slippage ковзання

2. Ask questions on the text.

3. Explain the use of different types of clutches.

4. Translate the folowing text into English.

Муфта

Муфта (від нім. Muffe) в тех­ніці — пристрій, що постійно або тимчасово з'єднує між собою вали, труби, сталеві кабелі чи ін. циліндричні деталі (вироби); передає обертовий рух і обертальні момен­ти з одного вала на інший або з вала на вільно розміщену на ньо­му деталь (напр., зубчасте колесо). До того ж, така муфта компенсує невеликі монтажні відхилення, роз'­єднує вали, запобігає виходу з ла­ду машини в аварійному режимі тощо. Розрізняють муфта жорсткі некомпенсуючі, або глухі— з жорстким з'єднанням дета­лей; жорсткі

компенсуючі (напр., деякі зубчасті) — з невеликим взаємним зміщенням з'єднуваних деталей; жорсткі рухомі (напр., кулачково-дискові) — зі

значним взаємним зміщенням з'єднуваних деталей; пружні, що

зменшують коливання і динамічні навантажен­ня (деякі — з незначним

зміщен­ням з'єднуваних деталей). Є муфти керовані, або зчіпні (напр., фрик­ційні — з використанням тертя) — зі з'єднанням і роз'єднанням дета­лей під час дії машини; самоке-ровані, або автоматичні, кінце­ві, стопорні та ін.