Английский язык в сфере машиностроения. Учебное пособие для студентов направления подготовки бакалавров 15.03.01-Машиностроение

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3.These drawings and their explanations are given to illustrate the principlesinvolved.

4.Different kinds of instruments are used to measure holes of considerable depth.

5.82millimetre is a measure of length.

6.Steel plates usually vary by sixteenths of an inch.

7.Bydividing the load required to break the specimen by its area, the ultimate tensile strength of material is obtained.

8.By accuracy of form ismeant not only the exact duplication of irregular profiles, but also the accuracy of form embodied in squares, true cylinders, cones, etc.

T EXT B: «MEASURING TOOLS»

When accurate measurement of the part is required, the vernier calipers, micrometers and slide gauges are used. When it is not so important to have an accurate measurement of the part, metal rules, inside calipers and outside calipers will do.

Steel rulesserve for determining the length and sometimes the depth of the part to be measured. Steel rules are graduated in millimetres, but in the USA and England they are graduated in thirty-seconds and sixtyfourths of an inch.

The outsidecalipersare the simplest instruments for measuring external diameters of the part. The outside caliper consists essentially of two curved legs.

The insidecalipersare used for determining the internaldiameters of the part. Its construction is almost similar to that of the outside calipers. Sometimes the outside calipers maybe used for measuring internal diameters of the part. The outside and insidecaliper measurements may be read by placing the legs of the calipers on a ruleand placing one leg and the end of the rule against a flat surface.

Verniercaliperscan be used for measuring both external and internal sizes of a part. By using vernier calipers measurements up to .001" may be determined. Vernier calipers consist of a primary steel scale and four jaws. The frame may be clamped on the scale in any position by means of an adjustingscrew.

The micrometeris an instrument for precise measurement of length and thickness of a part to one ten-thousandth of an inch. The principle of operation is similar to that of vernier calipers. A graduated thimbleserves as the primary scale. The scale on the barrel of the micrometer is used for" the vernierreading. The part to be measured is

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placed between the anviland micrometer screw, which is called a «movable spindle». By rotating the thimble, the spindle is removed or approached to the anvil. By rotating the ratchetthimblethe spindle is moved and thus the part is pressed to the anvil. Thereupon the rotation of the ratchet thimble is discontinued, the micrometer opening is fixed by the locknutand the reading is taken. The micrometer reading is the sum total of the barrel divisions, the thimble divisions with respect to the axial line on the barrel, and the vernier reading.

Adialindicator.The dial indicator is a gaugewith a graduated dial and an indicatorpointerconnected to a testpointby a system of levers. Any movement of the test point is magnified by the indicator pointer. The dial indicator is used to check the shape of a part, the precision of its machining, as well as for checking the accuracy of cuttingmachines.

Thread plug gauges or internal gauges, being of "go" and "no- go" type, are generally used for testing threadsor tapped holes.

Depthgaugesare used for measuring the depth of grooves and holes. Their principle of operation is similar to that of vernier calipers. A primary scale sliding in a frame may be locked in any position by a screw. The depth of a groove or a hole is measured by means of the primary scale and a vernier. Conical surfaces are measured with control gauges.

A universal angle gaugeis for measuring internal and external angles. The universal angle gauge consists of a base with a primary scale attached to the base.

A quadrantwith a vernier may be moved along the arc of the base. A triangle may be attached to the quadrant by means of a holder. In its turn a detachablerule is attached to the triangle. The triangle and the detachable rule can be moved along the face of the quadrant. Angles can be measured within the range of 0° to 320° by means of the universal angle gauge.

VOCABULARY:

accurate – меткий, точный, sliding – скользя правильный steelruler – стальная линейка scale – шкала, масштаб

primary – основной, первоначальный clamp – зажим(ать)

curvedlegs – изогнутые ножки attach – приспосабливать

jaw – губка, щека, кулачок(патрона) recess – углубление

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adjustingscrew – регулирующий винт precise – точный

depthrod – глубинный стержень barrel – вал, барабан verniercalipers – штангенциркуль anvil – наковальня с нониусом thimble – ковш; барабан микрометра rotate – вращать

reading – показание прибора locknut – контргайка

movablespindle – двигающийся шпиндель holder – держатель

ratchetthimble – трещетка; маховоймеханизм triangle – треугольник

arc – дуга

axialline – осевая линия withrespectto – к, в отношении testpoint – контрольная точка gauge – калибр; шаблон; измерять

indicatorpointer – стрелка индикатора lever(s) – рычаг, рукоятка, балансир magnify – увеличивать

precision – высокоточный прецизионный cuttingmachines – режущие машины threadpluggauges – резьбовой калибр thread – винтовая резьба, нарезка taphole(s) – гаечное отверстие

universalanglegauge – универсальный угловой калибр (шаблон) base – основание, исходный пункт

quadrant – дуга, квадрант, большой трензель detachable – съемный

EXERCISES:

1. Answer the following questions:

1.What is a micrometer?

2.What is the function of the graduated thimble of the micrometer?

3.What is the scale on the micrometer barrel used for?

4.Where is the part placed for measurement?

5.How is the part pressed to the anvil and how is the micrometer reading

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taken?

2. Translate the following words and word combinations:

vernier calipers, to be used, to measure, external and internal sizes, a part, to consist of, steel scale, four jaws, two jaws, to be attached, the frame, to slide, the scale, the first two jaws, to be used, measuring external surfaces, the other two jaws, measuring internal surfaces, the depth, to be measured, a spindle

TEXT C:«CONTROL SYSTEM ARCHITECTURE»

Control of complex systems is usually based on a hierarchical structure. This structure deals with the organization of the tasks necessary for FMS operation and how these different tasks are related. The tasks are arranged in the hierarchy on the basis of their function or their role in system operation. The differences between various types of FMS are the way the tasks are related to the system resources and the way they are divided or combined in sets of control programs.

A characteristic feature of this structure is that each level of the hierarchy must be able to function independently of levels above it. In other words, failure at the top does not cause stoppage of activities below; higher levels are intended to support lower level functions.

The functions which arc performed at the plant-wide level are as

follows:

-Plant-wide MRP (material requirement planning); -Plant-wide production plans;

-Plant-wide data-base management and information system These plant-wide functions will typically set overall targets and production goals for a long-term period. This information will usually reside in a mainframecomputer and will serve as inputs to the three levels

of operations described.

FMS Level-1

Operations include the following operational areas:

-Strategic decision-making for the FMS;

-Evaluating FMS performances;

-Ancillary support for FMS operation.

All the activities at this level will be supported by software on a mainframe computer. In some modifications a visible alternative is to have a separate medium-sized computer for these activities, which can be considered a Decision Support System (DSS) computer.

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FMS Level-2

Operations include decisions typically made by the FMS line supervisor, over a period of several days or weeks. The main tasks to be performed at this level are:

-Dividing overall production targets into batches of parts;

-Within each batch, assigning system resources1 in a manner which maximizes resource utilization, i.e. balancing workloads;

-Responding to changes in upper-level production plans с material availability.

All software decision aids typically reside on the FMS computer, or if this not feasible, then on a DSS computer.

FMS Level-3

Operations deal with the real-time operation of the FMS. The functional areas involved are:

-Work-order scheduling and dispatching (which part to introduce next into the FMS, and when);

-Movement of workpieces and material handling system (which machine to send this workpiece to next, which cart to sent to pick up this workpiece, etc.);

-Data distribution; -Tool management;

-System monitoring and diagnostics;

-Reacting to disruptions (failures if one or more system components, sudden changes in production requirements).

During normal system operation, most of these decisions are made by software in the FMS computer and/or MHS computer. However, when failure of a machine occurs, the FMS supervisor will usually take charge of the decision making. The FMS supervisor's task can be considerably simplified by employing various software decision aids which typically should reside on the FMS computer to enable rapid implementation of the changed decisions, but in some systems the architecture could involve use of separate DSS computer as described previously.

VOCABULARY:

hierarchical- иерархический relate– связывать

arrange– располагать resources– ресурсы combine– комбинировать

in other words – другимисловами

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target-цель

reside– располагать(ся) mainframecomputer–универсальный компьютер inputs– входные

evaluatе– оценивать ancillary – вспомогательный decision– решение

takecharge– взять на себя ответственность involve – включать

disruption-сбой, прерывание

1.When designing an FMS, the basic problem is to create cells from which the system is to be constructed.

2.Flexible manufacturing systems (FMSs) represent a new strategy to increase labour productivity.

3.The FMS is known to provide a direct hardware/software solution to many economic and technical problems.

4.The cart is considered to be a very simple and safe material handling device.

5.Fixtures are used to hold a part.

6.The part is found to be a workpiece processed by a flexible manufacturing system.

7.The FMS is designed to machine more than one part number at low to medium volume levels

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Содержание

Предисловие………………………..………………………………………4

Unit 1……………………………………..…….…………………………...5 Unit 2…………………………………………..…………………………..13 Unit 3………………………………………………..……….……..……...22 Unit 4……………………………………...…………….....…..…………..31 Unit 5………………………...……………………………….…..………..42 Unit 6…………...……………………………………………….......……..50 Unit 7...…………………………………………………...………………..59 Unit 8...………………………………………………………...…………..66 Unit 9…...…………………………………………………..……...............74 Unit 10……………...………………………………………..………….....80

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АНГЛИЙСКИЙ ЯЗЫК

В СФЕРЕ МАШИНОСТРОЕНИЯ

Учебное пособие для студентов направления подготовки бакалавров

15.03.01-Машиностроение

Могутова Оксана Александровна

Отпечатано в Белгородском государственном технологическом университете

308012, г. Белгород, ул. Костюкова, 4