- •Unit 3 turning and turning machines (lathes)
- •1. Read and memorize the following words and word-combinations:
- •Types of lathes
- •1. Give the main points of the text, answering the following questions:
- •2. Choose synonyms out of the following list:
- •3. Fill in the blanks with the suitable words from the text. The words are given below.
- •4. Perform the following tasks, basing of the text.
- •5. Characterize lathes according to the following plan:
- •Text 2 Engine Lathe
- •1. Give the main points of the text, answering the following questions:
- •2. Using the text, give derivatives from the following words and translate them into Russian:
- •3. Replace Russian words and word combinations by the corresponding English equivalents:
- •4. Make up questions to which the italicized words are answers:
- •5. Make up a summary of the text. Text 3
- •Vertical Eight - Spindle Semiautomatics
- •5. Give a brief summary of the text.
- •1. Answer the following questions, using the information from the text:
- •2. Translate the following groups of words, paying attention to the meaning of suffixed:
- •3. Fill in the blanks with the preposition: for, of, in, with, by, out, from, to.
- •4. Find the English equivalents for the following:
- •5. Supply the missing word:
- •Upright Drill Presses
- •1. Underline the suffixes in the following words and state what part of speech they belong to:
- •3. Translate the following sentences observing different meanings of the italicized words and word combinations:
- •4. Guess the meaning:
- •5. Describe the function and characteristics of the principal units of an upright drill press, using the active vocabulary of the text:
- •6. Try to translate the text without using the dictionary:
- •Radial Drills
- •1. Find in the text:
- •2. Find English equivalents:
- •3. Make sentences out of the two parts:
- •4. Translate the following in writing.
- •5. Make a brief summary of the text.
- •Unit 5 grinding and grinding machines
- •Purpose and Field of Application of Grinding Machines
- •Text 2 Cylindrical Grinding Machines
- •6. Summarize the text. Text 3
- •Internal Grinding Machines
- •1. Name the main points of the text answering the following questions:
- •2. Fill in the blanks using the words below:
- •3. Find in the text English equivalents for the following words and word combinations:
- •4. Using the text supply
- •5. Summarize the text.
3. Fill in the blanks with the preposition: for, of, in, with, by, out, from, to.
Drilling machines are designed ... producing trough and blind holes ... solid materials.
Employing special tools drilling machines can be used to cut ... large holes ... sheet metal ... trepanning.
The distance ... the spindle centre ... the face ... the column is one ... the principal dimensions ... a drilling machine.
Holes can be machined ... twist or core drills.
The drilling capacity ... 50 to 60 kg per sq mm is considered to be the main dimension ... a drilling machine.
4. Find the English equivalents for the following:
Станок для глубокого сверления, вертикально-сверлильный станок, радиально-сверлильный станок, тонколистовой метал, цековка, метчик, развертка, сталь средней твердости, лицевая сторона стойки, механический цех, сборочный цех, ремонтный цех, инструментальный цех, сервисная служба, передний конец шпинделя, сельскохозяйственное оборудование, заготовка
5. Supply the missing word:
In drilling h... in metal, different t... can be employed.
Threads are cut with t....
T... and b... holes can be produced in solid material.
Rough holes are made in the b... by drilling.
Drilling machines find application in machine, assembly and repair s...
T ext 2
Upright Drill Presses
The primary cutting motion of these machines is the rotation of the spindle which holds the cutting tool, while the feed motion is the axial motion of the spindle.
The workpiece is placed on the work table or directly on the base. The axis of the hole to be machined is aligned with the spindle axis by moving the workpiece along the table or base.
The principal units of an upright drill press are: column, base, speed gearbox, spindle, feed gearbox and feed mechanism and work table.
The column is a hollow box-shape casting which is mounted rigidly on the base and carries all other principal units. Vertical ways are provided on the front face of the column for the sliding spindle head and the table. The electric control devices and the spindle counterweight are housed in the cavity of the column.
The base is the footing on which the whole machine is supported. In the medium- and heavy-duty drill pressed, heavy workpieces are placed on the top surface of the base. The cavities of the base serve as a reservoir for the cutting fluid.
The speed gearbox usually consists of sliding gears which are engaged in various combinations to obtain different spindle speeds. The spindles of modern drill pressed run at 6 to 12 different speeds.
The spindle has a spline shank which fits the spline hole in the hollow shaft of the speed gearbox and rotates together with this shaft. At the same time the spindle can travel in the axial direction to provide the feed motion. The cutting tool is held at the lower and of this attachment.
The feed mechanism in upright drill pressed provides for power and hand feeds of the spindle. When power feeds are engaged, a clutch links the output shaft of the feed gearbox to the spindle quill. When manual feed is engaged, rotation is transmitted directly from the handwheel or pilot wheel to the pinion which meshes with the rack of the spindle quill. The mechanism is equipped with a device for automatically disengaging power feed when the preset depth of machining is reached. The table of the drill press is the unit on which the workpiece is clamped. It can usually be adjusted vertically along the column and can be swung out of the ways in machines with a round column to enable heavy work to be placed directly on the base. The table is mounted on the column way (box column), on the column itself (round column), or it is of box shape and is mounted on the base.
Special program-controlled tables are available for drilling a series of holes in a workpiece without resorting to a jig. First the coordinate dimensions of the holes are set up and then the table and the saddle are automatically positioned for each hole in a definite sequence. This procedure is repeated for each workpiece of the lot.
EXERCISES