Lesson 10

 Refresh the words in Ex. I (Lesson 9) and get ready to have a dictation.

II. Find the words in the text and translate the word combinations with these words.

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III. Work in pairs. Study the prompts in italics. Think of 2 or 3 sentences using the words from Ex. I applying the rule studied. Discuss

Pic. 16

Pic. 17

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V. Read the text and give the definition of the word “cell”.

CELLS AS

BASIC BUILDING BLOCKS OF FMSs

Сthan an operating group of several machines, perhaps with a material handlingиsystem that will work together but remain an isolated group, and cells that are made up of system-ready machines, specially planned for and intended to be expanded or integrated into a larger system.

The cell has always been considered as the basic building block of an FMS. And although there is a considerable activity in multiple-machine systems, the largest portion of the growth in interest in an FMS today is in

cells. This includes both cells that are never intended to be anything more

The cell has all the elements of a full FMS. Typically, the cell includes many manufacturing components such as two or three machine tools, material handling system, pallet changers, a workpiece store, a conveyor, robot, quality control system, host computer and management in-

growth in both the number of suppliers and users. Their appearance and frequent application closed an important gap between the individual machine tool and the interlinked systems.

For example, the plant has set up two separate flexible machining cells, each of which has its own manufacturing strategy. One cell is made up of three-axis machining centres with a conveyor for pallet transfer. Its application is the machining of highly complex workpieces. For the lower

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quality components flexible transfer line system incorporating 10 threeaxis machining centres has been installed. In both cells minicomputers are responsible for supervisory control and there is full control systems compatibility across the two cells due to the adoption of uniform standards.

Summing it up one must say that current developments and/or trends Сare towards flexible cells and FMS concepts because the main benefits include improved productivity, better quality of product, less operator de-

pendence, more machine uptime during which a module can process parts and the potential for an unmanned third shift. To realize these benefits, however, proper design of the system and proper organization of the work ofиthe whole factory are required.

It should also be stressed that the application of the cell covers a much broader user base than the manufacturing or assembly systems do. The cell concept of an FMS technology has found its way into nearly every sector of manufacturing. A cell offers the best potential for production cost savings in small-batch production. The high level of interest in cell technology comes entirely from the fact that cells are an important form of au-

VII. Find the synonyms (the second column) to the words from the text (the first column). Classify them according to the part of speech: verb, noun, adjective, and adverb. Make up 3 sentences using the words from all the groups and both columns.

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C. Using Lessons 6 – 10, make a crossword puzzle (10 words from Ex. I). Then let your groupmates do it.

TEST YOURSELF

The cell has always been considered as the 1) ___ building block of an FMS. And although there is a considerable activity in multiple-machine systems, the largest portion of the growth in interest in an FMS today is in 2) ___. This includes both cells that are never intended to be anything more than an operating group of several 3) ___, perhaps with a material handling

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4) ___ that will 5) ___ together but 6) ___ an isolated group, and cells that are made up of 7) ___ machines, specially planned for and intended to be 8) ___ or 9) ___ into a larger system.

automatically on more than one 19) ___ which pass through the system along different 20) ___.

It is important to note that one of the 21) ___ of cells is their 22) ___

which means that, if any cell breaks down for any reason, the production planning and control system can 23) ___ and 24) ___ the production. This can only be done if not only the process, but also the routing of the parts

time duringбwhich a module can process parts and the potential for an unmanned third shift. To realize these benefits, however, 32) ___ design of the system and 33) ___ organization of the work of the whole factory are

required.

How many mistakes have you done? What are they?

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II. Find the words in the text andДtranslate the word combinations with these words.

III. Work in pairs. Study the prompts in italicsИpaying attention to the use of the Articles. Think of 2 or 3 statements using the words from Ex. I. and discuss them in your group.

To initiate a particular program, the operator needs only call up the program name.

The features that make CNC the heart of an FMS can also be adopted on other  machines.

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IV. Read the text and label the pictures (pic. 18 – 25).

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adopted on other machines – for example, the CNC is almost the same as a robot controller.

In some installations, a number of CNC machines have been under minicomputer control and generally they are called DNC (direct numerical control) systems. Usually a DNC differs from an FMS in the ancillaries.

СFor example, tools may be supplied on wallets, along conveyors with the workpieces, and be loaded manually. Then, the workpiece is usually set up manually. In other cases, the system is designed to produce a small number of variations in a family of components, such as axles.

There are basically two types of CNC machines – lathes and machiningиcenters. All have similar control units. In a typical CNC lathe, there is a slant-bed with one or two turrets carrying tools for turning, boring, drilling and perhaps even grinding.

The movement of the tools both towards the spindle and towards the headstock canбbe controlled at various speed, while the spindle speed also can be varied infinitely. Then each tool can be used as required, all these functions being controlled automatically according to a present program.

As a general rule, in a FMS there are two common types of machining centres, those Аwith vertical and those with horizontal spindles. The horizontal types are mostly used owing to their greater flexibility.

The table carrying the workpiece can move horizontally in two planes, x and y, and it can also index around. Then, the spindle can be moved vertically. Thus, the workpieceДcan be indexed around 90° so that four faces can be machined at one setting. However, some machines either have a right angle attachment or have a special head design for machining the top face. On a vertical spindle, the table can be moved in the x and y planes, while the spindle can move vertically.

As with lathes, so with machining centres,Иthe spindle and table speeds can be varied infinitely, but, of course, to enable the machine to mill, drill, bore and tap, many different tools are needed. Therefore, a tool magazine is mounted on the side of the machine. The magazine is circular or rectangular, and it is indexed round so that the tool needed for the next operation can be moved in advance close to the loading station this device being called an automatic tool changer (ATC). Between the loading station and spindle there is a gripper which can pick up the tool from the spindle chuck – in some cases while the spindle is still rotating – remove it and place it in the magazine. Then it picks up the new tool and inserts it in the machine.

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It is worthy of note that the most important features of CNC machines are the servo-motors, which can be controlled so that theу can rotate at any speed.

Next, with electronic controllers, it became practical to put a series of steps in sequence and initiate those steps automatically.

СIt should be noted that large memory is needed so that many programs can be stored, and more complex programs be used. Most of the new CNC machines take advantage of the large memory to include standard programs for such operations as drilling and deep drilling carried out in stages.

V.иComplete the sentences.

1. A process computer gives the signal to …

2. Direct numerical control systems are often called … 3. A DNC differsбfrom an FMS in …

4. The two types of CNC machines are …

5. In a FMS there are two common types of machining centers … 6. The magazine is …

7. A gripper is used toА…

8. Most CNC machines need large memory as …

VI. Summarize the text. Read the tips in Home task 5.

VII*. Would you like to work withДsuch a CNC machine (pic. 26)?

Why? What could you do with its help? И

Pic. 26

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VIII. A. Watch video #5 (14:00) about CNC Machining to make up a list of special terms (10 as minimum) and give their definitions in English. Then play with your partner a game “hangman”. The winner is the person with the maximum of guessed words.

СB. Watch video #5 again and make up as many questions (general and special) as you can (6 as minimum). Ask and answer the questions of your groupmates. Choose the most interesting and unpredictable questions and answers.

C. Divide this video into smaller sequences (about 1 minute), choose one and try to learn it by heart. Act out an episode, copy the rhythm,

A.Memorize the words from Ex. I and be ready to do a dictation.

B.Write an abstract to the text “CNC machines and their control”.

Mind the structure:

1.Reason for writing: What is the importance of the research? Why would a reader be interested in the larger work?

2.Problem: What problem does this work attempt to solve? What is the scope of the project? What is the main argument, thesis or claim?

3.Methodology: An abstract of a scientific work may include specificД

models or approaches used in the larger study.ИOther abstracts may describe the types of evidence used in the research.

4.Results: An abstract of a scientific work may include specific data that indicates the results of the project. Other abstracts may discuss the findings in a more general way.

5.Implications: How does this work add to the body of knowledge on the topic? Are there any practical or theoretical applications from your findings or implications for future research?

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C. CNC machines have some problems. Go to the forum of practical machinists http://www.practicalmachinist.com/vb/cncmachining/?s=bb168ee26baebbee4376864e7534aebb and find the problems they discuss.

key feature of a computer 2) ___ control (CNC) machine is that several

Therefore, to initiate a particular sequence or program, the operator needs

steps can be carried out in 3) ___ without manual labour, and a number of differentиseries of machining operations can be stored in the 4) ____.

only 5) the program name or number, while a series of different

workpieces can be machined without 6) ____ to set the machine up or install new tools.бIt should be noted that the signal to initiate a program can

come equally from a process computer controlling a whole 7) ___. However, the features that make CNC the heart of an FMS can also be adopted on other machines – for example, the CNC is almost the same as a 8) ___ controller.

In some installations, a number of CNC machines have been under 9)

___ control and generally they are called DNC (10) numerical control)

19) ___ types are mostly used owing to their greater flexibility.

It is worthy of note that the most important features of CNC machines are the 20) ___, which can be controlled so that theу can 21) ___ at any speed.

It should be noted that 22) ___ memory is needed so that many programs can be stored, and more 23) ___ programs be used. Most of the new CNC machines take advantage of the 24) ___ memory to include standard

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