Контрольні завдання

Завдання 1. Назвіть / напишіть якомога більше слів та словосполучень, які називають:

а) процеси обробки;

6) металообробні .верстати;

в) інструменти.

Завдвння2. Назвіть / напишіть якомога більше сполучень із словами:

surface, chip, machining, resistance.

Завдання 3. Назвіть /напишіть якомога більше дієслів, значення яких пов’язане з обробкою матеріалів.

Завдання 4. назвіть / напишіть якомога більше слів з такими

а) суфіксами:

-tion, -еr, -ing, -able (-ible), -аl, -ly;

б) префіксами:

un-, rе-, under-, dis- ;

Завдання 5. Прочитайте та перекладіть на рідну нову такі речення:

1. In general, harder materials require lower cutting speeds for a given tool life and greater power, butt give better surface finish on the work.

2. Metals, having the same hardness but varying microstructure will cause significant differences in toll wear and life.

3. The chips are removed by pressures on the tool face just back of the cutting edge. In small broken, but only slightly distorted particles.

4. The tool scrapes (скребти) over me surface to even it up (зрівнювати), causing tool failure.

5. In ductile metals the chips are removed as continuous ribbons and with a great deal of plastic distortion, producing excessive heat in the shear zone ahead of the cutting edge.

6. This heat causes the tool to fail.

7. The chip is work-hardened and becomes harder than the original metal.

8. For mass production, steels are liven one heat treatment to provide a structure most suitable for rough machining, a second for finish machining, or form machining, and a third to assure the hardness, strength or ductility required for the end product.

9. The machinability of soft metals is improved by cold drawing to reduce ductility.

10. Metals of very high hardness are difficult and expensive to machine even with low speeds.

11. Grinding, machining at high temperatures, electro discharge machining, and ultrasonic machining are often used with hard metals.

12. Some steels that contain maganese and are used for quantity production of pleces that do not require high thermal or mechanical properties can be machined at higher cutting speeds.

13. Lead is sometimes added to steel and brass to make them free-machining.

14. Most special free-cutting steels, brass and aluminum are machined in the cold-drawn state in high-speed automatic screw machines.

Завдання 6. Прочитайте уголос та перекладіть подані нижче тексти:

а ) MACHINING.

Most metals can be machined. Machinability is best for metals that allow easy chip removal with minimum tool wear. Metals that worn harden, are porous or inhomogeneous, or are hard, reduce the life of cutting tools. Al, Mg, Zn and many Cu alloys machine better than free-machining steels such as bills. Be and some Ni and Тi alloys machine about 50% as well as bills steel. Refractory metals are more difficult to machine, often as low as 5-8% of bills.

b ) MOТІОН BETWEEN TOOL AHD WORK.

In power machining operations there must be a relative movement between cutting tool and workplace. During some machining operations the workplace moves; in others only the cutting tool moves; frequently both tool and workplace are in motion. The various machining operations that employ cutting tools use either a rotating or a traversing motion.

In certain cases an operation is accomplished by the motion of the tool on one machine and by motion of the workplace on another machine. An example is a drilling operation performed on a turret lathe; the drill is traversed without rotating, while the workplace revolves. Had the operation been done on a drill press, the workplace would have remained stationary while the drill rotated as a advanced into the work.

Many particular machining operations can be performed on a workplace most easily or most economically by a certain machine tool, although it is frequently possible to perform the operations on more than one type of equipment. Of primary consideration in fitting the job to the machine is the nature of the required operation.

Завдання 7. Прочитайте текст та передайте його зміст рідною новою.

SPEED AND FEED.

Two important considerations are present in the relative movement of the cutting tool and workplace: cutting speed and feed. The cutting speed is the relative surface speed between the work and the tool, cutting speed is commonly given in feet per minute. The feed is the relative amount of motion or travel of the cutting tool into the workplace per revolution, stroke or unit of time.

To obtain high machining efficiency, desired surface-finish, and appreciable tool life, speed and feed must be closely correlated during any machining operation. Many factors affect this relationship, including the type of tool used, its durability, and the rigidity of the machine and tool, as well as the power of, the machine, and the material hardness, and confutation of the workplace. No general rule or equation for the correct feed and speed can

cover all conditions. Some information comes from publications and head books some from, the advice of others, and much from personal experience.

Most manufacturers of machines and cutting tools supply information on recommended feeds and speeds for their particular product. In addition, machine shop handbooks tool used, its durability, and the rigidity of the machine and tool, as well as the power of the machine, and the material hardness, and confiscation of the workplace. No general rule or equation for the correct feed and speed can coverall conditions. Some information comes from publications and head books, some from the advice of others and much from persons: experience.

Most manufactures of machines cutting tools supply information on recommended feeds and speeds for their particular product. In addition, machine shop handbooks (довідник) provide adequate information on feeds and speeds for normal conditions encountered in machining.

Завдання 8. прочитайте текст; користуючись словником випишіть незнайомі слова; зробіть письмовий переклад тексту: