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Exercise 4.4 Increase Your Vocabulary

 

Give Ukrainian equivalent of the following:

 

1 to constitute core of manufacturing systems.

2 steam engine powered machine tools.

3 jigs and fixtures.

4 to shift from inflexible automation of mass production to flexible automation for batch production.

5 to improve the accuracy of performance.

6 to discharge electric sparks between the tools and the workpiece.

7 computer numerically controlled machine tools.

Exercise 4.5 Develop Your Idea about the Text

Make up a plan of the text.

 

Exercise 4.6 Controlled Practice

 

1 Copy out from the text sentences in Present Perfect Tense. Translate them into Ukrainian.

2 Put the following sentences into Perfect Tenses.

 

a) Undoubtedly by the next decade of this century new modern technologies in automation (to develop).

b) The lecturer said that during the past two decades, unprecedented change (to occur) in the competitive environment of the discrete part of manufacturing industry.

c) Process control (to be) most often associated with the processing industries, such as chemical processing, petroleum refineries, etc.

 

Exercise 4.7 Focus on Translation

 

Translate the following sentences into English.

 

1 .

2 , 䒺 - , .

3 ³, .

4 .

Exercise 4.8 Discussion Point

 

Talk it over.

 

1 Describe the process of development of machine tools.

2 What is the principle of work of machine tools?

Unit 5

Machine Programming

Pre-reading Task

 

Scan the text for answering the following questions:

 

1 Machine programs operate the system without human intervention, do not they?

2 What two basic categories can automation production be classified into?

 

Text

The actions performed by an automated system are determined by a program of instructions. The program operates the system without human intervention, although the automated process or procedure may involve human interaction (e.g., an automated teller machine). The instructions contained in the program specify the details of each action that must be accomplished, the sequence in which the actions must be performed, and variations in the sequence that may be required depending on circumstances.

In the simplest automated systems, the machine actions comprise a well-defined work cycle that is repeated continuously with little or no deviation from cycle to cycle. Many mass production operations fall into this category; examples include automatic screw machine cycles, stamping press operations, plastic molding, and die casting. These processes date back many decades, and the equipment has traditionally been controlled by hardware components such as cams, electromechanical relays, and limit switches. In addition to controlling the equipment, these components and their arrangement served as the program of instructions that regulated the sequence of actions in the work cycle.

Although these devices are often quite adequate for the modest control action requirements of these programs, modern controllers are based on microcomputers. The program of instructions for computer-controlled production equipment has included a variety of media over the years, such as magnetic tape, diskettes, computer memory, and other modern storage technologies.

Computer control provides the opportunity for additional functions to be incorporated in the operation, beyond simply regulating the machine cycle. Some of the additional functions include improving and upgrading the control software, including the addition of control functions not foreseen during initial equipment design; safety monitoring; monitoring of process data such as equipment performance and product quality; diagnostic routines for maintenance and to expedite repairs when equipment breakdowns occur; and a convenient human-machine interface. Modern computer-controlled programmable machines also are capable of higher level functions, such as decision making and process optimization.

The decision-making capability of the system is included in the program in the form of instructions that execute different actions depending on conditions and circumstances. Less than one set of conditions, the system responds one way, but under a different set of conditions, it responds in another way.

Decision making also allows an automated system to cope with unanticipated events in the work cycle, such as a broken tool or a part not positioned correctly in a fixture or other malfunction in the process. Many decision-making situations rely on the ability of the system to use sensors to monitor the process and sense the environment. The sensors indicate the presence of the unexpected event, and the program commands the system to deal with the event in an appropriate manner. This type of decision-making capability is often called error detection and recovery.

Process optimization is another aspect of programming in the operation and control of a production process. Optimization is applicable in situations where there is (1) a well-defined economic performance criterion, such as product cost, production rate, or process yield, and (2) the relationships between the process variables and the performance criterion are known. In these cases, the control program is designed to make adjustments in the process variables that tend to drive the process toward an optimal state.

 

Post-Text Exercises

 

Exercise 5.1 Read and Translate the Text into Ukrainian

Exercise 5.2 Comprehension Check

Answer the following questions:

 

1 What systems is automation concerned with?

2 What is fixed automation? What does it include?

3 What are the examples of fixed automation?

4 What is the major difference between fixed and programmable automation?

5 What features characterize programmable automation?

6 What are the examples of programmable automation?

7 What does the usual production cycle include?

8 What is the theoretical basis for flexible automation?

9 What are the features of flexible automation?

10 How does flexible automation system operate?

11 What are the reasons for automation?

12 What is the purpose of improving some fundamental strategies?

 

Exercise 5.3 Read for Specific Information

Read and translate the statements. Correct the statements if they are wrong.

 

1 The actions performed by an automated system are determined by a program of instructions.

2 In the automated systems, the machine actions comprise a well-defined work cycle that is repeated continuously with much deviation from cycle to cycle.

3 Computer control does not provide the opportunity for additional functions to be incorporated in the operation.

4 Modern computer-controlled programmable machines are not capable of higher level functions, such as decision making and process optimization.

5 Many decision-making situations rely on the ability of the system to use sensors to monitor the process and sense the environment.

 

Exercise 5.4 Increase Your Vocabulary

 

Learn the following words and word combinations.

 

to alter justifiable high demand rates a set of batch changeover high investment general purpose time-consuming step-reprogramming approach interrupt downloading per labor hour substitution insurance demeaning implementation unsafe consistency to achieve gains customer satisfaction by reducing something lead time intangible scrap rate

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