Vocabulary development: word building prefix re-

Префикс re- образует новые слова со значением «вновь», «заново», «пере»: remodeling – переоборудование. Слова с префиксом re- означают переделку или повторность действия: to reconsider – рассмотреть заново, пересмотреть.

Grammar study: modal function of the verb “to have”

Глагол «to have» может выполнять модальную функцию. Он является заменителем модального глагола «must» и переводится на русский язык как «должен», «обязан». Глагол to have в модальной функции употребляется с последующим инфинитивом:

Sample: To meet the demands for improving production, engineers have to search new technologies. – Чтобы удовлетворять требованиям улучшающегося производства, инженеры должны искать новые технологии.

Text

Read the text telling about improved automatic tool grinding

Unattended Tool Grinding

The combination of a loading robot and a CNC tool-and-cutter grinding machine allows unattended resharpening of endmills. Tool-resharpening shops not only have to produce CNC-quality tools that perform as well or better than new tools. To optimize the use of a CNC grinding machine, these shops must consider incorporating automatic tool loading and resharpening to complete jobs unattended during night shifts and weekends.

For tool-grinding shops, the greatest obstacle to unattended machining is the need to change parameters from tool to tool. Endmills come in a wide range of geometries, including number of flutes, left- or right-hand spirals, hook and clearance angles, and are made from various materials, such as carbide, HSS and cermet. They also have varying amounts of wear and nicks on their cutting edges.

Some customers may want their endmills reground completely (flute, diameter, and end). Others may request that only certain parameters be reconditioned (diameter, configurations and chamfers). Therefore, resharpening these endmills manually can be extremely time-consuming and labour-intensive. For a shop to grind tools profitably, it must automate the process.

A shop looking to upgrade its machinery and improve its productivity may consider investing in a 5-axis tool-and-cutter grinding machine with a 3-axis automatic tool loader and intelligent software. A machine capable of unattended resharpening should be equipped with a stationary dividing head and a double-end spindle to accept a maximum of six different grinding wheels.

With a CNC that incorporates digital AC drives and an integrated PC, the grinder can offer different options for sending or receiving data. The operator can communicate with the machine through a modem, printer port, or network. As operators load a pallet with endmills for an unattended shift, they must select tools with some features in common. The endmills have to be sorted and grouped by their shaft diameters since the installed collet or toolholder only allows a certain diameter tolerance. Besides, the two spindle ends do not have to be fitted with two wheels of different materials, each demanding its own schedule of maintenance and dressing.

For each tool, the operator must enter the pallet ID (inside diameter) number, row, column, tool type, special tool features (i.e. corner radius), number of teeth, end configuration, tool diameter and length, grinding length, and the amount of stock. The selected grinding operation (i.e. fluting, gashing, end grinding, or OD (outside diameter) grinding) can be activated when the corresponding tool features in the spreadsheet file are loaded into the PC.

A 3-D (3-dimensional) electronic probing system is used to determine the location of features on each tool once it is loaded into the grinder. It takes about an hour to complete programming for 80 endmills of different styles. Once the data are uploaded, the operator can set up the grinding machine for unattended operation.

Exercise 1. Translate the derivative words with the prefix re- and pre- :

resharpening, regrounding, reground, reconditioned, pre-assigned, precaution, to restrain.

Exercise 2. Translate the sentences with the verb «to have» in modal function:

1. Tool-resharpening shops have to produce high-quality tools.

2. The endmills have to be sorted and grouped by their shaft diameters.

3. The two spindle ends do not have to be fitted with two wheels of different materials.

4. For each tool, the operator has to enter the pallet with all necessary data.

5. Some endmills have to be reground completely, the others partially.

6. Tool-resharpening shops have to consider automatic tool loading to complete jobs unattended.

Exercise 3. Find in the text corresponding English sentences to the Russian ones:

1. Цехи перезаточки инструмента должны производить инструменты, соответствующие качеству компьютерных станков.

2. Для автономной работы в ночные смены должна соблюдаться автоматическая загрузка инструмента.

3. Сочетание загрузочных роботов и ЧПУ станков позволяет автономную перезаточку фрез.

4. Главной трудностью автономной обработки является смена параметров каждого инструмента.

5. Торцевые фрезы имеют различные геометрические показатели и сделаны из разных материалов.

6. Некоторые заказчики хотят переточить фрезы полностью, другие – только изменить некоторые параметры.

7. Делается также и ручная перезаточка фрез, но она является трудоемкой.

8. Для повышения продуктивности требуются многоосевые обрабатывающие станки и хорошее программное обеспечение.

9. Для автономной перезаточки станки должны быть оборудованы соответствующими устройствами.

10. Для загрузки в стеллаж оператор должен сортировать фрезы по параметрам.

11. На загрузку данных о фрезах требуется около часа.

Speaking:

Exercise 4. Give the summary of the text using key vocabulary and tell about:

1. what is unattended grinding;

2. what is the aim of applying this technology;

3. what does resharpening mills include;

4. the difficulties in this job;

5. the role of operator in this process.

Checklist for Section XI:

1. What is the meaning of the verb «to have» in the modal function?

2. What is the role of the prefix «re-» in word formation?

3. What is unattended tool grinding?

4. How is it necessary to organize the job to apply this technology?

Appendix I

Additional texts

Text I

Read the text telling about the emergence of machine-tools and their role in machinery:

to craft		мастерить, изготавливать
barrier	[′bærɪə]	барьер, преграда, препятствие
to dissolve		растворять(ся), исчезать
to spawn	[spɔ:n]	порождать, плодить (размножаться)
plan surface		плоская поверхность
surface plate		рихтовальная плита
marking compound		маркировочный состав
hand scraper		ручной скребок
successor	[sək′sesə]	преемник, наследник
to encourage	[ɪn′kʌrɪdʒ]	побуждать, поощрять, способствовать
to gain		получать
adverse		неблагоприятный
electrodischarge		электроразряд