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2. Дайте відповідь на запитання:

1. What are important alloying elements?

2. What treatment hardens the gear for longer life?

3. What do broaching machines cut?

4. What machines does tooth generation require?

3. Визначте вірне речення чи невірне згідно змісту тексту.

1. The process begins with forging or casting.

2. The gear blank is first machined normally on a lathe.

3. Slotters have cutting tools that rotate synchronously with gear blank and cut spurs or helical teeth.

4. Heat treatment doesn’t harden the gear for longer life and better performance.

5. Hardened gears are not used in marine, aerospace and automotive industry.

4. Перекладіть наступні речення з англійської мови на українську, звертаючи увагу на вживання інфінітиву.

1. Oil is known to be lighter than water.

2. We heard the channel Tunnel be nearly 52 km long.

3. They are supposed to begin their research in a few days.

4. We know the project of the channel Tunnel to be worked out by researchers of Great Britain,

5. The train is announced to be late an hour and a half.

5. Перекладіть наступні речення з української мови на англійську, звертаючи увагу на зворот there + be.

1. Є  потяг на Одесу, який відходить в десять годин ранку.

2. У цій кімнаті на кожному столі має бути лампа.

3.У вашій статті має бути більше цифр, що ілюструютьрозвиток нашої промисловості.

4. У нашому інституті дуже гарна бібліотека.

5. Нікого не було удома, коли я прийшов.

6. Оберіть вірний варіант.

1. Nobody… thirsty.

a) aren’t b) is

c) are d) isn’t

2. « What happened? »”He…”

a) runned away b) is run away

c) ran away d) run away

3. ”…”,they decided.

a) Let we make tea b) Let is make tea

c) Let’s make tea d) Let’s made tea

4. Mary and Dick… in the sitting –room.

a) was b) wear

c) were d) is

5. The girl…

a) standed up b) stood up

c) up standed d) up stood

7. Утворіть форми Participle I та Participle II від наступних дієслів.

To dig

To do

To draw

To play

To like

ВАРІАНТ 6

1. Прочитайте та перекладіть українською мовою, перепишіть та письмово перекладіть весь текст.

Design for Machining

When choosing the material for a component the designer must consider applicability, cost, availability, machinability, and the amount of machining required. Each of these factors influences the others so that the final optimum choice will be a compromise bet­ween conflicting requirements. The choice will depend on the com­ponent’s function and will be influenced by such factors as strength, resistance to wear, appearance, corrosion resistance, etc. The next step includes consideration of all factors that minimize the final cost of the component: purchase cost, production cost that is non-productive time and actual machining operations. With the exception of workpieces that are partially formed before machining, such as forgings, castings, welded structures, the choice of the shape of the workplace material depends only on availability. Metals are usually sold in plates, sheets, bars, rods, strips or in the tube form. The designer should check up on standard sha­pes and sizes and then design components that require a minimum of machining. Parts that are manufactured from a circular or hexagonal bar or tube are generally produced on machine tools that apply rotary motion of the workplace. The remaining components are manufactured from square or rectangular bars, plates, or sheets by the operations which rely on the tool rotation. In some cases many shapes are difficult or even impossible to produce by conven­tional machining operations. For examples, it is easy to produce a cylindrical hole in a workpiece but to produce a square or irregular -shaped hole of similar size is much more difficult. In ad­dition, some materials are very hard or brittle, or there may be a demand to cut very small parts or fine details.

There are many ways to reduce manufacturing costs and to increase machining productivity. These measures include using:

  • Improved materials, tools and processes.

  • More effective organization of production, material handling, and assembly technologies.

  • Automation wherever it increases efficiency.

Most components must be assembled and the designer should give consideration to the assembly process.

A further requirement is that each operating machined surface on a component should have a corresponding machined surface on the mating component to provide a roper fitting. Incorrect specification of tolerances can make assembly difficult or even impossible.