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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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programs for such operations as drilling and deep drilling carried out in stages.

How many mistakes have you done? What are they?

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 concerning the Gerund and Participle I. Think of 2 or 3 sentences using the words from Ex. I.

V. Read the text and find the description to the picture above.

WORKPIECE TRANSFER TECHNOLOGY

Pallet is a device which serves as a standardized conveyance for the part in FMS; it may be an integral part of a cart.

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To turn a machining cell into FMS with low manning, mechanical handling devices are needed. Since the workpieces at machining centres are usually large and heavy, some form of pallet changing and handling is necessary. The machines are equipped with either a multi-station pallet carrier or an APC (automatic pallet changer). Many APCs are separate

Сunits, controlled by the CNC, but handling should be quicker and simpler with an integrated design.

The APC is available in many types ( pic. 27). These types are used depending on the requirements of machining centres (MCs) and other ma-

chines.

Robot type is used as an automatic workpiece changer (AWC), and supplies workpieces on a compact loop conveyor and uses a robot to load and unload the workpieces. It is known to be widely used for compact ma-

chining centres and NC lathes.

и Dual бtype is a simple APC which incorporates only a load-

ing/unloading device in pallets. Various types are available in small to large sizes. It is used as a transfer unit for the unmanned trailer.

Shuttle type. The dual type APC is shuttled in parallel to the X axis or У axis of the machiningАcentre. Pallets are changed at one place.

Turn type. This APC changes pallets by loading/unloading of pallets and turn operation. This type is believed to be convenient because workpiece can be set up at a predetermined place.

Rotary type is generally used as a loop APC or pallet magazine with four or more pallets. It is incorporated with a loading/unloading device at the

Square type is a sequential typeДwhich loads and unloads pallets at two places of X axis of the machining centre, i.e. loads from A and unloads from B. It performs loading/unloading and travel by combination of transfer bar and conveyor.

longitudinal centre portion, and can be connected with a maximum of two machining centres. It is often connected with a setup station for effective

workpiece setup. И

Index type. It is the turn type APC equipped with a predetermined angle indexing function and provided with a pallet stand in the periphery.

Separate type is connected with a pallet stand which is equipped with a loading/unloading device in the extended direction of both ends of the X axis of the MC table, a large-sized type being used for vertical boring machines. In this case, the shuttle type APC may sometimes be set on the extension side of the X axis.

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