Λύσεις — Κεφάλαιο 6: Machine Tools (σελ. 127-158) – VOCATIONAL LANGUAGE LEARNING COURSEBOOK FOR MECHANICAL ENGINEERING TECHNICIANS Β ΕΠΑΛ

VOCATIONAL LANGUAGE LEARNING COURSEBOOK FOR MECHANICAL ENGINEERING TECHNICIANS Β ΕΠΑΛ VOCATIONAL LANGUAGE LEARNING COURSEBOOK FOR MECHANICAL ENGINEERING TECHNICIANS Β ΕΠΑΛ – ΛΥΣΕΙΣ – ΑΠΑΝΤΗΣΕΙΣ Ασκήσεων Σχολικού Βιβλίου Λύσεις — Κεφάλαιο 6: Machine Tools (σελ. 127-158) – VOCATIONAL LANGUAGE LEARNING COURSEBOOK FOR MECHANICAL ENGINEERING TECHNICIANS Β ΕΠΑΛ

Λύσεις — Κεφάλαιο 6: Machine Tools

Ενδεικτικές λύσεις των 45 κλειστών ασκήσεων της ενότητας (σελ. 127-158): ιστορική εξέλιξη εργαλειομηχανών, προϊόντα/λειτουργίες κοπής, ο τόρνος και τα μέρη του, NC/CNC εργαλειομηχανές (MCU, θέσεις κοπής, workholding/tooling/monitoring devices).

Εργαλεία ανά εποχή και ιστορική σειρά (σελ. 127)

Ερώτηση: 1. A. Match the tools with the age they belong to. Tools: 1. Machine tools, 2. Tools made of iron, 3. Tools made of stone, 4. NC/CNC machine tools, 5. Tools made of steel, 6. Tools made of bronze. Ages: a) Stone age, b) Computer age, c) Bronze age, d) Machine age, e) Iron age, f) Steel age. B. Use the spaces provided to number the ages according to their historical order.

Απάντηση:

A. 1-d (Machine tools → Machine age), 2-e (Tools made of iron → Iron age), 3-a (Tools made of stone → Stone age), 4-b (NC/CNC machine tools → Computer age), 5-f (Tools made of steel → Steel age), 6-c (Tools made of bronze → Bronze age).
B. Ιστορική σειρά: 1. Stone age, 2. Bronze age, 3. Iron age, 4. Steel age, 5. Machine age, 6. Computer age.

Σύνοψη: (ενδεικτική) Κάθε εργαλείο αντιστοιχίζεται στη σωστή εποχή· η ιστορική σειρά είναι: λίθος → χαλκός → σίδηρος → χάλυβας → εργαλειομηχανές → υπολογιστής.

Διάγραμμα τύπων εργαλειομηχανών (σελ. 128)

Ερώτηση: 2. Complete the diagram with the types of machine tools mentioned in the text. MACHINE TOOLS: Manually operated — NC/CNC.

Απάντηση:

Manually operated: mechanical saws, drills, planes, lathes, grinding machines, milling machines (vertical/horizontal), broachers.
NC/CNC: NC and CNC cutting machines — milling machines, single-spindle drilling machines, lathes, turning (and chucking) centres, machining centres.

Σύνοψη: (ενδεικτική) Το διάγραμμα «MACHINE TOOLS» χωρίζεται σε δύο κλάδους: Manually operated (πριόνια, δράπανα, πλάνες, τόρνοι, μηχανές λείανσης/φρεζαρίσματος, broachers) και NC/CNC (machining/turning centres, CNC φρέζες/δράπανα/τόρνοι).

Σωστή επιλογή για εργαλειομηχανές (σελ. 128)

Ερώτηση: 3. Tick the correct alternative. 1. All machine tools, either manually operated or computer controlled are: a) forging machines, b) cutting machines, c) forming machines. 2. «NC and CNC machine tools are capable of machining to very close tolerances» means that: a) they reduce production costs, b) their products are made very quickly, c) their products are characterized by high precision/accuracy.

Απάντηση:

1-b: όλες οι εργαλειομηχανές είναι cutting machines (μηχανές κοπής).
2-c: «machining to very close tolerances» σημαίνει ότι τα προϊόντα τους χαρακτηρίζονται από υψηλή ακρίβεια.

Σύνοψη: (ενδεικτική) Οι σωστές απαντήσεις είναι 1-b (cutting machines) και 2-c (high precision/accuracy).

Αγγλικοί όροι εργαλειομηχανών (σελ. 128)

Ερώτηση: 4. Write the English equivalent term for the machine tools below. 1. μηχανοκίνητο δράπανο, 2. μηχανή αυλακώσεως, 3. μηχανοκίνητο πριόνι, 4. τόρνος, 5. εργαλειομηχανή πολλαπλών κατεργασιών για αντικείμενα εκ περιστροφής/τόρνος πολλαπλών κατεργασιών, 6. κατακόρυφη φρέζα, 7. μηχάνημα λειάνσεως-ακονίσματος, 8. πλάνη, 9. οριζόντια φρέζα, 10. εργαλειομηχανή πολλαπλών κατεργασιών για πρισματικά αντικείμενα.

Απάντηση:

1. μηχανοκίνητο δράπανο = drilling machine (drill).
1. μηχανή αυλακώσεως = broacher (broaching machine).
1. μηχανοκίνητο πριόνι = mechanical saw.
1. τόρνος = lathe.
1. τόρνος πολλαπλών κατεργασιών (για αντικείμενα εκ περιστροφής) = turning (and chucking) centre.
1. κατακόρυφη φρέζα = vertical milling machine.
1. μηχάνημα λειάνσεως-ακονίσματος = grinding machine.
1. πλάνη = plane (planer).
1. οριζόντια φρέζα = horizontal milling machine.
1. εργαλειομηχανή πολλαπλών κατεργασιών για πρισματικά αντικείμενα = machining centre.

Σύνοψη: (ενδεικτική) Κάθε ελληνικός όρος αντιστοιχίζεται στον αγγλικό όρο του κειμένου (σελ. 126-127), όπως παραπάνω.

Ερωτήσεις κατανόησης — εξέλιξη εργαλειομηχανών (σελ. 129)

Ερώτηση: 5. Answer the questions. 1. Has the development of hand and machine tools affected our lives? How? 2. What led man to the invention of machine tools? 3. What are the advantages of NC and CNC machine tools compared to the conventional ones?

Απάντηση:

1. Yes — man has improved his standards of living and increased his productivity thanks to the development of tools and machines.
1. His attempt to achieve higher precision and improved production rates led him to manufacture machine tools.
1. NC/CNC machine tools enable industry to produce metal parts with greater accuracy, efficiency, reliability, speed and closer tolerances than conventional (manually operated) machines.

Σύνοψη: (ενδεικτική) Οι τρεις απαντήσεις προκύπτουν αυτούσιες από το εισαγωγικό κείμενο «From Stone Tools to CNC» (σελ. 126-127).

Ομαδοποίηση συνωνύμων (σελ. 129)

Ερώτηση: 6. Make groups of words similar in meaning. Word bank: advance, make, period, effort, fabricate, discover, lately, ability, improve, age, precision, progress, create, invent, try, time, manufacture, develop, standard, design, attempt, epoch, produce, accuracy, efficiency, degree, construct, correctness, rate, skill, exactness, proportion, recently, effectiveness. Headings: progress, produce, rate, efficiency, accuracy, age, invent, attempt, recently.

Απάντηση:

progress: advance, improve, develop.
produce: make, fabricate, manufacture, construct, create.
rate: degree, proportion, standard.
efficiency: effectiveness, ability, skill.
accuracy: precision, correctness, exactness.
age: period, time, epoch.
invent: create, design, discover.
attempt: effort, try.
recently: lately.

Σύνοψη: (ενδεικτική) Οι λέξεις ομαδοποιούνται κάτω από τη συνώνυμη επικεφαλίδα τους, όπως παραπάνω.

Προϊόντα εργαλειομηχανών (σελ. 130)

Ερώτηση: 1. A lot of the most widely used metal parts are manufactured on machine tools. Tick those of the items below that are products of such machines. 1. Spring, 2. Curved part, 3. Fitting (angle), 4. Nut, 5. Bush, 6. Bolt, 7. Angular plate, 8. Washer, 9. Tin rivet, 10. Gear, 11. Shaft, 12. Threaded part, 13. Screw, 14. Nail, 15. Angular part.

Απάντηση:

Τυπικά προϊόντα εργαλειομηχανών (τόρνος/φρέζα/δράπανο): Nut (4), Bolt (6), Gear (10), Shaft (11), Threaded part (12), Screw (13), Bush (5) — κατασκευάζονται με τόρνευση/φρεζάρισμα/διάτρηση.
ΔΕΝ είναι τυπικά προϊόντα εργαλειομηχανών (κατασκευάζονται συνήθως με τύπωση/κάμψη λαμαρίνας, όχι κοπή σε εργαλειομηχανή): Spring (1, τυλίσσεται), Curved part/Angular plate/Angular part (2,7,15, κάμπτονται), Washer (8, τύπωση), Tin rivet (9, τύπωση), Fitting/angle (3, μπορεί να είναι χυτό ή λαμαρίνας), Nail (14, τύπωση).

Σύνοψη: (ενδεικτική) Κυρίως προϊόντα εργαλειομηχανών: nut, bolt, gear, shaft, threaded part, screw, bush — τεμάχια που παράγονται με τόρνευση, φρεζάρισμα ή διάτρηση, όχι με κάμψη ή τύπωση λαμαρίνας.

Κριτήρια αξιολόγησης:

Πρόσεξε: spring, washer, nail, tin rivet παράγονται συνήθως με άλλες μεθόδους (τύπωση, τύλιξη), όχι σε εργαλειομηχανή κοπής.

Ελληνικός όρος για κάθε λειτουργία εργαλειομηχανής (σελ. 131)

Ερώτηση: 2. A. Write the equivalent Greek term for each operation. 1. Broaching, 2. Planing, 3. Cutting a slot, 4. Facing, 5. Milling, 6. Grinding, 7. Reaming, 8. Drilling, 9. Threading, 10. Boring, 11. Turning, 12. Cutting/turning a taper.

Απάντηση:

1. Broaching = αυλάκωση (με μηχανή αυλακώσεως).
1. Planing = πλάνισμα.
1. Cutting a slot = διάνοιξη αύλακος/σχισμής.
1. Facing = μετωπική τόρνευση.
1. Milling = φρεζάρισμα.
1. Grinding = λείανση.
1. Reaming = γλύφανση.
1. Drilling = τρυπάνισμα/διάτρηση.
1. Threading = κοχλιοτόμηση.
1. Boring = διαμήκης εσωτερική διάνοιξη.
1. Turning = διαμήκης εξωτερική τόρνευση.
1. Cutting/turning a taper = κωνικό τορνάρισμα.

Σύνοψη: (ενδεικτική) Κάθε λειτουργία αποδίδεται στον ελληνικό τεχνικό όρο που χρησιμοποιεί και το σταυρόλεξο της σελ. 134 (π.χ. reaming = γλύφανση, broaching = αυλάκωση, boring = διαμήκης εσωτερική διάνοιξη).

Κριτήρια αξιολόγησης:

Η «γλύφανση» είναι το reaming (γλύφανο = reamer), όχι το grinding· το grinding είναι «λείανση».

Πρόταση περιγραφής λειτουργίας εργαλειομηχανής (σελ. 132)

Ερώτηση: B. Say how each operation is performed, e.g. Broaching can be carried out / performed / done with / on a broacher.

Απάντηση:

Planing can be performed on a plane (planer).
Cutting a slot can be done with a milling machine or a shaper.
Facing can be carried out on a lathe.
Milling can be done on a milling machine.
Grinding can be performed with/on a grinder.
Reaming can be carried out with a reamer.
Drilling can be done with/on a drilling machine.
Threading can be performed with a tap and die, or on a lathe.
Boring can be carried out on a lathe or a boring machine.
Turning can be performed on a lathe.
Cutting/turning a taper can be done on a lathe.

Σύνοψη: (ενδεικτική) Κάθε λειτουργία περιγράφεται με το μοτίβο «... can be carried out/performed/done with/on ...», όπως στο παράδειγμα του βιβλίου.

Ποια εργαλειομηχανή περιγράφεται (σελ. 133)

Ερώτηση: 4. Which machine tools are described below? 1. A is one of the most productive machine tools. It is very efficient in producing round parts, but it can also produce square, hexagonal and irregular ones. It can perform many operations including facing, cutting off, turning tapered sections, cutting threads, drilling, boring, reaming and also filing and polishing. 2. The is one of the most versatile machine tools used to cut straight, angular or irregular surfaces, slots, grooves and gear teeth. 3. A is used to cut off amounts of metal from the surface of a workpiece by moving the cutting tool forward and backward. 4. The is a machine tool used to cut holes in metal pieces.

Απάντηση:

1. lathe (τόρνος) — παραγωγικότερη εργαλειομηχανή, στρογγυλά/τετράγωνα/εξαγωνικά/ακανόνιστα τεμάχια.
1. milling machine (φρέζα) — ευθείες/γωνιακές/ακανόνιστες επιφάνειες, αυλακώσεις, δόντια γραναζιών.
1. plane (πλάνη) — αφαίρεση μετάλλου από την επιφάνεια με εμπρός-πίσω κίνηση του κοπτικού εργαλείου.
1. drilling machine (δράπανο) — κοπή οπών.

Σύνοψη: (ενδεικτική) Οι τέσσερις εργαλειομηχανές είναι: 1. lathe, 2. milling machine, 3. plane, 4. drilling machine.

Πίνακας: εξάρτημα, λειτουργίες, εργαλειομηχανή (σελ. 133)

Ερώτηση: 5. In the table below, write the main operations performed and the machine tools used to produce the following parts: 1. bolts, 2. shafts, 3. gears, 4. nuts, 5. bushes.

Απάντηση:

1. bolts: cutting off, turning, threading — on a lathe.
1. shafts: turning, facing — on a lathe.
1. gears: milling (cutting gear teeth) — on a milling machine.
1. nuts: turning, drilling, threading — on a lathe/drilling machine.
1. bushes: turning, boring — on a lathe.

Σύνοψη: (ενδεικτική) Κάθε τεμάχιο αντιστοιχίζεται στις κύριες λειτουργίες κατασκευής του και στην εργαλειομηχανή που χρησιμοποιείται, όπως παραπάνω.

Αναγνώριση λειτουργίας από ορισμό (σελ. 133)

Ερώτηση: 6. Identify the operation described. 1. is the operation performed to cut a hole of a standard diameter in a metal piece. 2. is used for producing angular or curved cuts, single or double slots in the external surface of a workpiece. 3. is the operation of removing an amount of metal from the end (face) of a workpiece to shape it. 4. is carried out with a rotating wheel, to finish a produced part and make its surface smooth. 5. is the operation of enlarging a previously cut hole to the desired accurate size. 6. is the operation of removing an amount of metal from the upper surface of a metal piece with a cutting tool which moves forward and backward. 7. is the operation performed with a special cutting tool on a cylindrical workpiece to produce threaded parts. 8. is the operation of accurately sizing and producing a good surface finish in the inside of a hole previously drilled or bored. 9. ___ is used for producing complicated internal shapes, cutting slots, etc.

Απάντηση:

1. Drilling.
1. Milling.
1. Facing.
1. Grinding.
1. Boring.
1. Planing.
1. Threading.
1. Reaming.
1. Broaching.

Σύνοψη: (ενδεικτική) Κάθε ορισμός αντιστοιχίζεται στη σωστή λειτουργία: drilling, milling, facing, grinding, boring, planing, threading, reaming, broaching.

Κριτήρια αξιολόγησης:

Boring μεγαλώνει μια ήδη ανοιγμένη οπή στο επιθυμητό μέγεθος (5)· reaming δίνει ακριβές μέγεθος και καλό φινίρισμα σε οπή που έχει ήδη ανοιχτεί με drilling ή boring (8).

Crossword — ελληνικοί όροι λειτουργιών εργαλειομηχανών (σελ. 134)

Ερώτηση: 7. Crossword puzzle. Across: 1. Γλύφανση, 2. Αυλάκωση, 3. Τρυπάνισμα, 4. Διαμήκης εξωτερική τόρνευση, 5. Πλάνισμα, 6. Διάνοιξη αύλακος/σχισμής. Down: 1. Κωνικό τορνάρισμα, 2. Φρεζάρισμα, 3. Διαμήκης εσωτερική διάνοιξη, 4. Κοχλιοτόμηση, 5. Λείανση, 6. Μετωπική τόρνευση.

Απάντηση:

Across: 1. Γλύφανση = REAMING, 2. Αυλάκωση = BROACHING, 3. Τρυπάνισμα = DRILLING, 4. Διαμήκης εξωτερική τόρνευση = TURNING, 5. Πλάνισμα = PLANING, 6. Διάνοιξη αύλακος/σχισμής = CUTTING A SLOT.
Down: 1. Κωνικό τορνάρισμα = CUTTING A TAPER, 2. Φρεζάρισμα = MILLING, 3. Διαμήκης εσωτερική διάνοιξη = BORING, 4. Κοχλιοτόμηση = THREADING, 5. Λείανση = GRINDING, 6. Μετωπική τόρνευση = FACING.

Σύνοψη: (ενδεικτική) Οι 12 όροι είναι οι 12 λειτουργίες της Άσκησης 2Α: reaming, broaching, drilling, turning, planing, cutting a slot (Across)· cutting a taper, milling, boring, threading, grinding, facing (Down).

Κριτήρια αξιολόγησης:

Στο πλέγμα οι όροι πολλών λέξεων (CUTTING A SLOT, CUTTING A TAPER) χωρίζονται με μαύρα τετράγωνα.

Μέρη του τόρνου και ελληνικός όρος (σελ. 136)

Ερώτηση: 1. Make a list of the parts of the lathe above and then, write the equivalent Greek term for each one. 1. e.g. motor = (ηλεκτρο)κινητήρας.

Απάντηση:

motor = (ηλεκτρο)κινητήρας.
headstock = κεφαλή τόρνου.
headstock spindle = άξονας κεφαλής.
live centre = ζωντανό κέντρο.
dead centre = νεκρό κέντρο.
toolholder = εργαλειοφορέας.
slides = οδηγοί ολίσθησης.
tailstock = κεντροφόρος/νεκρή κεφαλή.
feed lever = μοχλός πρόωσης.
lathe bed = κρεβάτι τόρνου.
handwheel = χειροτροχός.

Σύνοψη: (ενδεικτική) Κάθε εξάρτημα του τόρνου (σελ. 136) αποδίδεται στον ελληνικό του όρο, όπως παραπάνω.

Χαρακτηριστικά μερών του τόρνου (σελ. 137)

Ερώτηση: 3. Write the characteristics of the parts of the lathe as presented in the manual. 1. Headstock of design of design 2. Tailstock made of 3. Bed of 4. Handwheel

Απάντηση:

1. Headstock of compact design, of vibration free design.
1. Tailstock vibration free, made of high quality grey cast iron, easily clamped in any position.
1. Bed of high grade cast iron.
1. Handwheel with accurately adjustable scale rings.

Σύνοψη: (ενδεικτική) Τα χαρακτηριστικά κάθε εξαρτήματος προκύπτουν αυτούσια από τις λεζάντες του διαγράμματος (σελ. 136), όπως παραπάνω.

Φράσεις-ορισμοί στα χαρακτηριστικά του τόρνου (σελ. 137)

Ερώτηση: 4. Find words or phrases in the characteristics of the lathe's parts which mean: 1. A design/construction that consists of parts firmly joined, fitted, or fastened: 2. Rapid and continuous movement to and from tremble: 3. An accessory in the form of a circle that can be accurately set to different positions or sizes: 4. A part that is easily put or fastened in various positions firmly and tightly: 5. These parts are made of a high quality metal and are having high standards: 6. It is specially constructed so that it doesn't shake when the machine is in operation:

Απάντηση:

1. compact (design).
1. vibration (τρέμουλο/δόνηση).
1. (accurately adjustable) scale rings.
1. easily clamped in any position.
1. high grade cast iron / high quality grey cast iron.
1. vibration free.

Σύνοψη: (ενδεικτική) Κάθε ορισμός αντιστοιχίζεται στη λέξη/φράση των χαρακτηριστικών του τόρνου (σελ. 136), όπως παραπάνω.

Αναγνώριση εξαρτήματος τόρνου από περιγραφή (σελ. 138)

Ερώτηση: 5. Identify the part of the lathe described. 1. The is the part of the lathe on which the cutting tools are fastened. 2. The two metal rods on which the toolholder and the tailstock move are the . 3. The is the part of the lathe where the workpieces are fastened. Its spindle turns rotating the piece to be cut. 4. The is an electrical machine used to rotate the spindle which holds the metal pieces to be machined. 5. The supports the other end of the long cylindrical pieces fastened on the live centre. 6. The controls the amount that the cutting tool advances into a workpiece, that is, the amount of metal removed from it. 7. By turning the ___, the tailstock moves on the slides.

Απάντηση:

1. toolholder.
1. slides.
1. headstock.
1. motor.
1. tailstock.
1. feed lever.
1. handwheel.

Σύνοψη: (ενδεικτική) Κάθε περιγραφή αντιστοιχίζεται στο σωστό εξάρτημα του τόρνου: toolholder, slides, headstock, motor, tailstock, feed lever, handwheel.

Προτάσεις για τον τόρνο (αντιστοίχιση) (σελ. 138)

Ερώτηση: 6. Make meaningful sentences by matching their parts. 1. Machinists, mechanics and other technicians need a lathe 2. Using a lathe we can make 3. The handwheel is equipped with 4. A good lathe is the most important factor 5. What matters in a lathe is 6. The bed and tailstock of the lathe in the picture 7. Its tailstock and headstock 8. Machine tools produce parts — a. for the shape, size and precision of the work produced on it. b. are made of high quality cast iron. c. faster, more accurately and at a lower cost than hand tools. d. bolts, shafts, nuts, bushes, threaded parts, etc. e. the quality of its parts. f. for turning, facing, boring, reaming and threading metal parts. g. are designed to absorb vibration. h. accurately adjustable scale rings.

Απάντηση:

1-f: ...need a lathe for turning, facing, boring, reaming and threading metal parts.
2-d: Using a lathe we can make bolts, shafts, nuts, bushes, threaded parts, etc.
3-h: The handwheel is equipped with accurately adjustable scale rings.
4-a: A good lathe is the most important factor for the shape, size and precision of the work produced on it.
5-e: What matters in a lathe is the quality of its parts.
6-b: The bed and tailstock of the lathe in the picture are made of high quality cast iron.
7-g: Its tailstock and headstock are designed to absorb vibration.
8-c: Machine tools produce parts faster, more accurately and at a lower cost than hand tools.

Σύνοψη: (ενδεικτική) Πλήρης αντιστοίχιση 1-8 → a-h με ολοκληρωμένες προτάσεις, όπως παραπάνω.

ACTIVE — PASSIVE VOICE (τόρνος και εργαλειομηχανές) (σελ. 139)

Ερώτηση: 7. ACTIVE – PASSIVE VOICE. Decide if the sentences below should be in the active or in the passive voice and form the verbs in parentheses in the appropriate active or passive tense. 1. The cutting tools (fasten) on the toolholder of the lathe. 2. The tailstock and the toolholder of the lathe (move) on the slides. 3. The cutting tools used on machine tools (make) of steel. 4. The tool has become dull, so it must (sharpen) . 5. Before starting welding you must (choose) the appropriate electrode for the job. 6. In the future, thanks to the new developments in computer technology, most factories (control) by computers. 7. By fixing another wheel, grinders can also (do) polishing and buffing. 8. The metal construction (fix) in place with bolts and nuts only five minutes ago. 9. When everybody had finished, the teacher (check) all the metal parts produced by the students on the milling machine. 10. He (use) a grinder to sharpen the chisel. 11. CNC machine tools widely (accept) all over the world and soon (replace) conventional machines due to their accuracy, versatility and productivity. 12. The surfaces of the metal pieces to be joined should (clean) ___ with a sandpaper or sandcloth.

Απάντηση:

1. are fastened (passive).
1. move (active).
1. are made (passive).
1. be sharpened (passive).
1. choose (active).
1. will be controlled (passive).
1. do (active).
1. was fixed (passive).
1. checked (active).
1. used (active).
1. are widely accepted / have been widely accepted ... will soon replace (passive ... active).
1. be cleaned (passive).

Σύνοψη: (ενδεικτική) Κάθε ρήμα μπαίνει στη σωστή ενεργητική ή παθητική φωνή/χρόνο, όπως παραπάνω, ανάλογα με το αν το υποκείμενο ενεργεί ή δέχεται την ενέργεια.

Κρυμμένες λέξεις — μέρη του τόρνου (word search) (σελ. 139)

Ερώτηση: 8. Find nine parts of the lathe hidden horizontally, vertically or diagonally in this word square.

Απάντηση:

Τα 9 κρυμμένα εξαρτήματα στο πλέγμα των γραμμάτων είναι:
1. TAILSTOCK — οριζόντια, 1η γραμμή.
1. HEADSTOCK — διαγώνια, από την αρχή της 2ης γραμμής προς τα κάτω δεξιά.
1. MOTOR — οριζόντια, 3η γραμμή.
1. HANDWHEEL — οριζόντια, 4η γραμμή.
1. SPINDLE — κάθετα, 1η στήλη (από την 5η γραμμή).
1. SLIDES — κάθετα, 5η στήλη (από την 6η γραμμή).
1. TOOLHOLDER — κάθετα, 10η στήλη (από την 1η γραμμή).
1. FEED LEVER — κάθετα, τελευταία στήλη (γραμμένο «FEEDLEVER»).
1. LATHE BED — οριζόντια, 10η γραμμή (γραμμένο «LATHEBED»).

Σύνοψη: (ενδεικτική) Τα 9 κρυμμένα εξαρτήματα είναι ακριβώς τα 9 εξαρτήματα του τόρνου που παρουσιάζονται στο διάγραμμα της σελ. 136: tailstock, headstock, motor, handwheel, spindle, slides, toolholder, feed lever, lathe bed.

Εισαγωγικές ερωτήσεις — NC και CNC (σελ. 140)

Ερώτηση: Introduction. Read the text that follows and answer the questions. 1. Which characteristics of NC machine tools have brought tremendous changes in the metal working industry? 2. When was NC first introduced? 3. What is NC? 4. What are the applications of NC and CNC?

Απάντηση:

1. Their accuracy, reliability, productivity and repeatability have brought such tremendous changes that we can speak of a second industrial revolution.
1. NC was first introduced in the mid 50's.
1. NC is a means of guiding machine tools through various motions automatically, without human assistance.
1. Besides machine tools, NC and CNC are used on welding machines and inspection systems, and in most manufacturing and assembly processes.

Σύνοψη: (ενδεικτική) Οι τέσσερις απαντήσεις προκύπτουν αυτούσιες από την εισαγωγική παράγραφο της σελ. 140.

Σημασία λέξεων με έντονη γραφή (bold) (σελ. 141)

Ερώτηση: What do the bold-typed words or phrases mean? Tick the correct answer. 1. NC and CNC machine tools have been widely accepted thanks to their productivity... □ a) to produce precise parts Their ability □ b) to opeate automatically □ c) to produce a large number of parts in a short time 2. NC and CNC machine tools have been widely accepted thanks to their repeatability... □ a) to produce large numbers of identical parts (=similar parts at the same degree of accuracy) Their ability □ b) to receive a large number of instructions □ c) to display the dimensions of the machined parts on a screen 3. NC is now used to inspection systems... □ a) speeding up Systems □ b) programming the operation of the machine □ c) supervising 4. NC is now used in assembly processes... a) processes of disconnecting parts b) procedures carried out to put parts together (e.g. of a machine) c) operations of checking the production

Απάντηση:

1-c: productivity = their ability to produce a large number of parts in a short time.
2-a: repeatability = their ability to produce large numbers of identical parts.
3-c: inspection systems = systems supervising (the production).
4-b: assembly processes = procedures carried out to put parts together.

Σύνοψη: (ενδεικτική) Οι σωστές σημασίες είναι: productivity=1c, repeatability=2a, inspection=3c, assembly=4b.

Αντιστοίχιση παραγράφων-ερωτήσεων και απαντήσεις — η λειτουργία του NC/CNC (σελ. 141)

Ερώτηση: PRE-READING TASKS. 1. Familiarize yourself with the questions below. Then, go through the paragraphs about NC and CNC machine tools that follow and find which paragraph includes the answer to each question. Questions: 1. What is the function of the MCU in a CNC machine tool? 2. What potentials have the developments in the automatically controlled machines and the advances in computer technology opened to industry? 3. What is NC? 4. How are machine tools guided to find the cutting points? 2. After you have matched paragraphs with questions, read the paragraphs carefully and answer the questions.

Απάντηση:

Αντιστοίχιση ερώτησης → παραγράφου: Q1 (function of MCU) → παράγραφος 2. Q2 (potentials opened to industry) → παράγραφος 4. Q3 (what is NC) → παράγραφος 1. Q4 (how machine tools are guided to cutting points) → παράγραφος 3.
Πλήρεις απαντήσεις: 1. (παρ. 2) The MCU converts the coded instructions of the part program into a series of pulses of electric current which control the machine's motors and servomechanisms in order to produce the designed metal parts. 2. (παρ. 4) The developments have made it possible to program and control the operations of a complete manufacturing plant by a computer communication network (CAM), making the automated and unattended factory a reality; this will further increase productivity and improve the quality of products (the second industrial revolution). 3. (παρ. 1) NC is the operation of a machine by a series of coded instructions that consist of numbers, letters of the alphabet and symbols listed in a logical order. 4. (παρ. 3) The positions of the cutting points are given to the NC machine tool in two systems: the incremental (each position given from the previous cutting point) and the absolute (all positions given from a zero reference point).

Σύνοψη: (ενδεικτική) Η αντιστοίχιση ερώτησης-παραγράφου είναι: ερώτηση 1→παρ. 2, ερώτηση 2→παρ. 4, ερώτηση 3→παρ. 1, ερώτηση 4→παρ. 3· οι πλήρεις απαντήσεις δίνονται παραπάνω με τη σειρά των ερωτήσεων.

Τίτλοι στις παραγράφους του κειμένου NC/CNC (σελ. 144)

Ερώτηση: 1. Give headings to the paragraphs of the text. Write them in the spaces provided over each paragraph.

Απάντηση:

Παράγραφος 1: What is NC/CNC (the part program).
Παράγραφος 2: The function of the MCU.
Παράγραφος 3: Positioning systems (incremental and absolute).
Παράγραφος 4: The potential of CAM and the automated factory.

Σύνοψη: (ενδεικτική) Κάθε παράγραφος παίρνει έναν σύντομο ενδεικτικό τίτλο, όπως παραπάνω, ανάλογα με το κύριο θέμα της.

Ελληνικά δάνεια στην αγγλική γλώσσα (σελ. 144)

Ερώτηση: 2. Greek words in the English language. Many English words have derived from the Greek language. Are there any in the above text? Find them. e.g. series = σειρά/ακολουθία.

Απάντηση:

Λέξεις ελληνικής προέλευσης στο κείμενο (σελ. 142-143), εκτός από το παράδειγμα series = σειρά/ακολουθία:
alphabet = αλφάβητο· symbols = σύμβολα· logical = λογικός· program = πρόγραμμα.
machine = μηχανή· servomechanisms = (σερβο)μηχανισμοί· system(s) = σύστημα.
electric = ηλεκτρικός (< ήλεκτρον)· technology = τεχνολογία· automatically / automated = αυτόματα / αυτοματοποιημένος (< αυτόματος).

Σύνοψη: (ενδεικτική) Ελληνικής προέλευσης λέξεις του κειμένου: alphabet, symbols, logical, program, machine, (servo)mechanisms, system(s), electric, technology, automatically/automated.

Κριτήρια αξιολόγησης:

Λέξεις όπως computer, industry, potential, numerical, positions είναι λατινικής προέλευσης· δεν ανήκουν στη λίστα.

Φράσεις-ορισμοί μέσα στο κείμενο NC/CNC (σελ. 144)

Ερώτηση: 3. Find the terms or phrases used in the text to express the following: 1st paragraph a) A number of instructions arranged in a certain order. They are used to express information in a form that a computer can understand: b) The places where the machine tool must cut the metal to construct the designed metal part: c) The program which is created in a computer and gives the NC/CNC machine tool the necessary instructions that will control it to produce the designed metal part: d) The activity of putting data into a computer and giving it the appropriate instructions that will enable it to solve problems, provide us with information, drawings, etc.: e) A computer which is included in the MCU as part of it: f) A system of instructions which is put / inserted in the part of the computer where information is stored: g) Any revisions of the part program can be put in the computer's memory and kept there until they are needed: 2nd paragraph Temporary increases in the level of electric current: 3rd paragraph a) Method of finding the exact point at which a cutting operation is to be performed by a machine tool on a metal part: b) A mistake made at the positioning of a cutting point will continue to exist to all the cutting points that follow, which will all be at the wrong location: c) A fixed location on a metal part from which we measure all the dimensions in order to find the cutting points (when using the absolute positioning system): 4th paragraph a) Machine tools that operate controlled by a computer program, not by people: b) The great progress made in computer technology has created new possibilities for industry to become more effective, productive and successful in the future: c) A number of computers that are connected and operate together as a system: d) The process of using computers in industry to control the operation of the machines that manufacture the products: e) A large industrial plant which operates controlled by a system of computers. Because of that, only few workers are needed in the manufacturing process: f) This will result in producing more products than before and of a better quality: g) Such important changes / advances have occurred in industry, that the manufacturing processes have changed completely:

Απάντηση:

1st παράγραφος: a) coded instructions. b) cutting points. c) the part program. d) data processing. e) a computer (built in the MCU). f) program (loaded into the CNC computer's memory). g) can be stored for future use.
2nd παράγραφος: pulses (of electric current).
3rd παράγραφος: a) positioning system. b) it will be carried over to all the cutting locations after this point. c) a zero reference point.
4th παράγραφος: a) automatically controlled machines. b) tremendous advances (in computer technology have opened new potentials to industry). c) a computer communication network. d) CAM (Computer Assisted Manufacturing). e) the automated and unattended factory. f) increase productivity and improve the quality of products. g) the second industrial revolution.

Σύνοψη: (ενδεικτική) Κάθε ορισμός/περιγραφή αντιστοιχίζεται στον όρο/φράση του κειμένου NC/CNC (σελ. 142-143), όπως παραπάνω.

Ερωτήσεις κατανόησης — λειτουργία NC/CNC (σελ. 145)

Ερώτηση: 4. Answer the questions. 1. What does the part program consist of? 2. What sort of information is given to the NC/CNC machine by the coded instructions of the part program? 3. What makes the control unit of a CNC machine «think»? 4. Is it possible to revise the part program for future use? 5. What does the MCU of a CNC machine tool include? 6. What were the first machine control units like? 7. Which positioning system is better? Why? 8. What is the effect of the new technological developments on industry?

Απάντηση:

1. It consists of coded instructions made up of numbers, letters and symbols, listed in a logical order.
1. Information about the dimensions, shapes, sizes of products, the positions of the cutting points and the operations/motions the machine will perform.
1. The program loaded into the CNC computer's memory makes the control unit «think».
1. Yes — any revisions can be made at the machine and stored for future use.
1. It includes a computer, a monitor and a keyboard (the computer is either built in the MCU or connected to it).
1. They were bulky vacuum tube units.
1. The absolute system is better, because an error in one position is not carried over to the next positions (unlike in the incremental system).
1. They have opened new potentials to industry, making the automated, unattended factory a reality and increasing productivity/quality (the «second industrial revolution»).

Σύνοψη: (ενδεικτική) Οι οκτώ απαντήσεις προκύπτουν αυτούσιες από το τετρα-παραγραφικό κείμενο «THE FUNCTION OF NC AND CNC» (σελ. 142-143).

Αντιστοίχιση λέξεων με ορισμούς (σελ. 146)

Ερώτηση: 5. Match words with definitions. a) able to change easily and adapt to different conditions b) a number of things or events that come one after the other 1. unattended 2. bulky c) large and heavy, difficult to move or deal with 3. improve d) a characteristic that makes something less useful or 4. flexible successful than other things 5. disadvantage e) to make something greater in number, level or amount 6. potential f) not being watched or looked after 7. increase 8. series g) the necessary abilities or qualities to become successful or useful in the future h) to make something better

Απάντηση:

1-f (unattended: not being watched or looked after).
2-c (bulky: large and heavy, difficult to move).
3-h (improve: to make something better).
4-a (flexible: able to change easily and adapt).
5-d (disadvantage: a characteristic that makes something less useful).
6-g (potential: necessary abilities/qualities to become successful in the future).
7-e (increase: to make something greater in number/level/amount).
8-b (series: a number of things that come one after the other).

Σύνοψη: (ενδεικτική) Πλήρης αντιστοίχιση 1-8 → a-h, όπως παραπάνω.

Ζεύγη συνωνύμων (NC/CNC λεξιλόγιο) (σελ. 146)

Ερώτηση: 6. Make pairs of synonyms, by matching the words in column A with those in column B. A: motion, plant, information, total, revision, error, reality, advance, potential. B: progress, data, change, movement, possibility, whole, mistake, factory, fact.

Απάντηση:

motion — movement.
plant — factory.
information — data.
total — whole.
revision — change.
error — mistake.
reality — fact.
advance — progress.
potential — possibility.

Σύνοψη: (ενδεικτική) Τα εννέα ζεύγη συνωνύμων είναι: motion/movement, plant/factory, information/data, total/whole, revision/change, error/mistake, reality/fact, advance/progress, potential/possibility.

Ταξινόμηση λέξεων σε κατηγορίες (NC/CNC) (σελ. 146)

Ερώτηση: 7. Arrange the words below under the appropriate column. Words: productivity, absolute, motors, reliability, incremental, servomechanisms, repeatability, accuracy, controls, flexibility, machine control unit. Columns: Properties of NC/CNC machine tools, Parts of machine tools, Positioning systems.

Απάντηση:

Properties of NC/CNC machine tools: productivity, reliability, repeatability, accuracy, flexibility.
Parts of machine tools: motors, servomechanisms, controls, machine control unit.
Positioning systems: absolute, incremental.

Σύνοψη: (ενδεικτική) Οι λέξεις κατατάσσονται στις τρεις στήλες όπως παραπάνω.

Εισαγωγικές ερωτήσεις — χαρακτηριστικά NC/CNC (σελ. 147)

Ερώτηση: Introduction. Do you know the answer to these questions? If not, read the text that follows and find out. 1. Why do NC/CNC machine tools represent a large investment for any industry? 2. What has made NC/CNC machines so widely accepted throughout the world? 3. Which feature makes these machines able to perform a great variety of machining operations in only one set up?

Απάντηση:

1. Because they help improve productivity and reduce manufacturing costs, so industry invests heavily in them to gain a bigger share of the market.
1. Their accuracy and ability to use up to six axes of motion, which lets them perform a great variety of operations and produce complex cuts impossible on conventional machines.
1. Their ability to use up to six axes of motion (mainly turning and machining centres) makes them able to machine all sides of a workpiece in only one set up.

Σύνοψη: (ενδεικτική) Οι τρεις απαντήσεις προκύπτουν αυτούσιες από την εισαγωγική παράγραφο (σελ. 147).

Εξαγωγή σημασίας άγνωστων λέξεων — επενδύσεις/κόστος (σελ. 148)

Ερώτηση: Deducing the meaning of unknown words. Go through the text to identify the words or phrases defined below. 1. : to have the plan or intention; to want and try to do something. 2. : to attract more customers, sell more products and thus make a bigger profit. 3. : money spent on buying equipment which is considered useful and profitable as it can increase productivity and improve the quality of products. 4. : the loading and fastening of a workpiece on a machine tool. 5. : to make something as little as possible; to reduce it to the smallest possible amount; to minimize it. 6. : useless pieces of metal which remain after the machining of a workpiece; chip; waste.

Απάντηση:

1. aim (industry always aims at producing better products).
1. gain a bigger share of the market.
1. investment.
1. set up (setup).
1. eliminate.
1. scrap.

Σύνοψη: (ενδεικτική) Οι έξι ορισμοί αντιστοιχίζονται στις λέξεις/φράσεις: aim, gain a bigger share of the market, investment, set up, eliminate, scrap.

Αντιστοίχιση χαρακτηριστικών CNC με επεξηγήσεις (σελ. 148)

Ερώτηση: The Most Important Features of CNC Machines. What do you think they refer to? Match them with the explanations below. 1. Tooling systems, 2. Workholding devices, 3. Chip removal, 4. Machine operation monitoring systems, 5. Loading and unloading of workpieces — matched with a-e.

Απάντηση:

1-c (Tooling systems: devices/systems to remove a tool and insert a new one for the next operation).
2-a (Workholding devices: devices to put and hold workpieces securely on the machine table).
3-d (Chip removal: devices to remove scrap from the machine).
4-e (Monitoring systems: systems that check the operation of the machine and/or the produced parts).
5-b (Loading/unloading: devices to load workpieces and remove finished parts).

Σύνοψη: (ενδεικτική) Πλήρης αντιστοίχιση 1-5 → a-e, όπως παραπάνω.

Τίτλοι στις θεματικές ενότητες (workholding, loading, chip removal, tooling, monitoring) (σελ. 149)

Ερώτηση: Read the text, check your answers to the previous task and give titles to the thematic areas the text is divided into. Write the titles in the spaces provided.

Απάντηση:

Θεματική ενότητα 1 (σελ. 149): Workholding devices (jigs, fixtures, chucks).
Θεματική ενότητα 2 (σελ. 150): Loading and unloading of workpieces (pallets, robot loaders, bar feeders).
Θεματική ενότητα 3 (σελ. 151): Chip removal (chip conveyor).
Θεματική ενότητα 4 (σελ. 151-152): Tooling systems (tool-storage magazines, automatic tool changers, revolving turrets).
Θεματική ενότητα 5 (σελ. 152-153): Machine operation monitoring systems (tool monitoring, in-progress gauging).

Σύνοψη: (ενδεικτική) Οι πέντε θεματικές ενότητες του κειμένου (σελ. 149-153) αντιστοιχούν στα πέντε χαρακτηριστικά της προηγούμενης άσκησης, με τους τίτλους όπως παραπάνω.

Ελληνικοί όροι για workholding/loading/chip removal/tooling (σελ. 153)

Ερώτηση: EXERCISES 1. Deducing the meaning of unknown words. A. Find the English equivalent to the following Greek terms. 1st thematic area 1. (ιδιο)συσκευές για πρόσδεση των προς κατεργασία κομματιών στις εργαλειομηχανές ψηφιακού ελέγχου: 2. κομμάτια για κατεργασία: 3. τζόγος, λάσκο, παίξιμο: 4. σφιγκτήρας, τσοκ (τόρνου, δράπανου): 5. μεγάλη ποικιλία/ευρεία γκάμα: 6. συσκευές πρόσδεσης αντικειμένων για κατεργασία: 7. τράπεζα εργαλειομηχανής: 2nd thematic area 1. συσκευή όπου στερεώνονται τα προς κατεργασία αντικείμενα που τοποθετούνται στην τράπεζα της εργαλειομηχανής και απομακρύνονται απ’ αυτήν με αυτόματο μηχανισμό / παλέτα: 2. απομάκρυνση κατεργασμένου κομματιού από την εργαλειομηχανή: 3. φόρτωση κομματιού για επεξεργασία σε εργαλειομηχανή: 3rd thematic area 1. νεκρός χρόνος: 2. συσκευή απομάκρυνσης και μεταφοράς απόβλητου /γρεζιών: 3. ανακύκλωση: 4th thematic area 1. κοπτικά εργαλεία: 2. βάρδια: 3. μηχανισμός/συσκευή τοποθέτησης εργαλείων / εργαλειοφορείο CNC εργαλειομηχανής: 4. περιστρεφόμενο, κυκλικού σχήματος εργαλειοφορείο/ρεβόλβερ/μύλος/τουρέλα: 5. μηχανισμός ή εξάρτημα εναλλαγής εργαλείων: 5th thematic area 1. σύστημα ελέγχου εργαλείων: 2. φθαρμένο, αμβλυμένο εργαλείο: 3. αντισταθμίζω: 4. σύστημα ελέγχου εργαλείων και κομματιών στη διάρκεια της κατεργασίας: 5. ανάπτυξη θερμότητας: 6. ψυκτική ουσία / ψυκτικό (υγρό): 7. κόστος κατασκευής:

Απάντηση:

1η θεματική: 1. jigs and fixtures, 2. workpieces, 3. chatter, 4. chuck, 5. a wide range / a great variety, 6. workholding devices, 7. (machine) table.
2η θεματική: 1. pallet, 2. unloading, 3. loading.
3η θεματική: 1. non-machining time, 2. chip / swarf conveyor, 3. recycling.
4η θεματική: 1. cutting tools, 2. shift, 3. tool-storage magazine, 4. revolving turret, 5. tool changer.
5η θεματική: 1. tool monitoring system, 2. worn / dull tool, 3. to compensate (for), 4. in-progress gauging system, 5. thermal growth, 6. coolant, 7. manufacturing cost(s).

Σύνοψη: (ενδεικτική) Κάθε ελληνικός τεχνικός όρος αντιστοιχίζεται στον αγγλικό όρο των πέντε θεματικών ενοτήτων (σελ. 149-153), όπως παραπάνω.

Φράσεις-ορισμοί στο κείμενο (workholding/loading/chip removal/tooling/monitoring) (σελ. 154)

Ερώτηση: B. Look through the text to find the words or phrases defined below. 1st thematic area: 1. to put something in a particular place, 2. to reduce something to the lowest possible level, 3. power or forces exercised on an object to hold it tightly, 4. to have the ability to deal with something successfully. 2nd thematic area: 1. to make less, 2. finished part, 3. a number of items one can choose from. 3rd thematic area: 1. to take something away from a place, 2. large boxes used for storing or transporting things. 4th thematic area: 1. to succeed in doing something, 2. at the same time. 5th thematic area: 1. happening while the machine is in operation, 2. to regularly check a process, 3. the process of looking carefully at every part of an object to check that it is all right, 4. new things or methods of doing something, 5. to give care to/deal with something.

Απάντηση:

1η θεματική: 1. locate, 2. eliminate, 3. gripping forces, 4. handle.
2η θεματική: 1. reduce, 2. machined part, 3. (a number of) options.
3η θεματική: 1. remove, 2. containers.
4η θεματική: 1. achieve, 2. simultaneously.
5η θεματική: 1. in-progress, 2. monitor, 3. inspection, 4. innovations, 5. attend (to).

Σύνοψη: (ενδεικτική) Κάθε ορισμός αντιστοιχίζεται στη λέξη/φράση του κειμένου, όπως παραπάνω.

Αναγνώριση συσκευής συγκράτησης/φόρτωσης (σελ. 155)

Ερώτηση: 2. Identify the workholding device described. Devices: 1. Parts catcher 2. Parts loader/unloader 3. Robot loader 4. Bar feeder — a) It places individual workpieces into the machine and removes the finished parts from it. b) It is capable of handling long bars, thus eliminating the loading of individual parts. c) It catches the finished parts and removes them from the machine. d) It communicates with the MCU and is capable of doing a variety of different operations, such as loading/un-loading parts, removing workpieces from pallets conveying parts to gauging stations or storage places, changing chuck jaws, etc.

Απάντηση:

a-2 (Parts loader/unloader: places workpieces and removes finished parts).
b-4 (Bar feeder: handles long bars, eliminates individual loading).
c-1 (Parts catcher: catches finished parts and removes them).
d-3 (Robot loader: communicates with the MCU, performs varied operations).

Σύνοψη: (ενδεικτική) Αντιστοίχιση: a-Parts loader/unloader, b-Bar feeder, c-Parts catcher, d-Robot loader.

Ταξινόμηση συσκευών/συστημάτων CNC μηχανών (σελ. 155)

Ερώτηση: 3. Classify the devices or systems used in CNC machines in categories as follows: a) Workholding devices, b) Workpieces loaders/unloaders, c) Chip removing devices, d) Tool-storage devices, e) Tool-changing devices, f) Monitoring systems.

Απάντηση:

a) Workholding devices: jigs, fixtures, chucks.
b) Workpieces loaders/unloaders: pallets/pallet changers, robot loaders, bar feeders, parts loaders/unloaders, parts catchers.
c) Chip removing devices: chip (swarf) conveyor.
d) Tool-storage devices: tool-storage magazines (chain conveyors, revolving turrets).
e) Tool-changing devices: automatic tool changers/robots.
f) Monitoring systems: tool monitoring system, in-progress gauging system.

Σύνοψη: (ενδεικτική) Οι συσκευές/συστήματα του κειμένου (σελ. 149-153) κατατάσσονται στις έξι κατηγορίες όπως παραπάνω.

Σωστό ή Λάθος — χαρακτηριστικά CNC μηχανών (σελ. 156)

Ερώτηση: 4. Are the sentences below true or false? 1. Machining centres can operate on up to 6 axes of motion, so they can perform complex operations on a workpiece in only one setup. 2. The new jigs and fixtures are more complicated and demand more storage space. 3. The design of the new workholding devices reduces loading and unloading time. 4. Robots can load workpieces and change tools and chuck jaws, and they can also perform some machining operations. 5. To remove a tool and insert a new one in the spindle, a tool changer needs no more than 4 seconds. 6. A large tool-storage magazine can take up to 120 tools, while a revolving turret up to 18. 7. The two independently operating turrets of a turning centre can machine the inside and outside surface of a workpiece simultaneously. 8. Part catchers belong to the tool-changing devices. 9. Tool-monitoring systems can control the flow of coolant and inspect the cutting tools and machined parts in the machine. 10. More than one CNC machine tools can be attended to by only one operator.

Απάντηση:

1. True — machining/turning centres use up to 6 axes, performing complex operations in one setup.
1. False — the new jigs/fixtures are simpler and reduce storage space.
1. True — the new workholding devices make loading/unloading easier and quicker.
1. False — robots load/unload workpieces, remove workpieces from pallets, convey parts, change tools and chuck jaws, but they do not perform machining operations.
1. False — a tool changer needs less than 6 seconds, not 4.
1. True — a tool-storage magazine can store up to 120 tools, a revolving turret up to 16-18.
1. True — the two turrets can machine the same workpiece simultaneously on both diameters/sides.
1. False — part catchers belong to the loading/unloading (workpiece-handling) devices, not tool-changing.
1. False — it is the in-progress gauging system (not the tool monitoring system) that controls the flow of coolant and makes possible the inspection of machined parts in the machine.
1. True — thanks to the innovations, one operator can attend to more than one machine.

Σύνοψη: (ενδεικτική) True: 1, 3, 6, 7, 10. False: 2, 4, 5, 8, 9 — διορθώνονται όπως παραπάνω με βάση το κείμενο (σελ. 147-153).

Χαρακτηριστικά NC/CNC ανά κριτήριο (σελ. 156)

Ερώτηση: 5. Write the features of NC/CNC machine tools which: a) increase machine utilisation time, b) reduce storage-space requirements, c) provide better tool and machine protection, d) increase the accuracy of the machined parts: e.g. the use of computers to produce the part program, e) reduce production costs.

Απάντηση:

a) Chip conveyors, automatic tool changers and pallet-changing systems reduce non-machining/downtime and so increase machine utilisation time.
b) The new, simpler jigs and fixtures reduce the storage space and cost required for their design and manufacture.
c) Tool monitoring and in-progress gauging systems detect worn/broken tools and provide better tool and machine protection.
d) The use of computers to produce the part program; the absolute positioning system; in-progress gauging systems that compensate for tool wear or thermal growth.
e) Reduced operator attendance (one operator for more than one machine), faster tool/workpiece changing, and fewer jigs/fixtures needed — all reduce manufacturing costs.

Σύνοψη: (ενδεικτική) Κάθε κριτήριο αντιστοιχίζεται στα σχετικά χαρακτηριστικά NC/CNC του κειμένου (σελ. 147-153), όπως παραπάνω.

Ερωτήσεις κατανόησης — workholding/loading/monitoring (σελ. 157)

Ερώτηση: 6. Answer the questions. 1. What are the advantages of the CNC workholding devices? 2. How is the loading and unloading of large workpieces achieved? 3. What is usually used to load/unload small-size workpieces? 4. Do the new tool-storage and tool-changing devices save time and increase productivity? Why? 5. Which is the most common tool-storage device used in turning and chucking centres? 6. What must be done to compensate for the dullness of a cutting tool? 7. Why do in-progress gauging systems reduce inspection time? 8. Why does the demand for reduced operator attendance decrease production costs?

Απάντηση:

1. They reduce storage space/cost, locate workpieces more accurately, hold them more securely (eliminating chatter), and make loading/unloading easier and faster.
1. Large pieces are fastened on pallets which are automatically loaded/unloaded from the machine table via a pallet-changing system.
1. Robot loaders.
1. Yes — because tools are inserted into the spindle quickly and accurately (in less than 6 seconds), saving time and increasing productivity.
1. The revolving turret (multi-tool revolving turret).
1. The system automatically reduces the speed or feed of the cutting tool.
1. Because they make it possible to inspect machined parts while they are still in the machine, between operations, instead of removing them for separate inspection.
1. Because one operator can attend to more than one machine, so fewer operators are needed, reducing labour costs.

Σύνοψη: (ενδεικτική) Οι οκτώ απαντήσεις προκύπτουν αυτούσιες από το κείμενο «Features of NC/CNC Machines» (σελ. 147-153).

Συγκριτικός βαθμός επιθέτων/επιρρημάτων (πλεονεκτήματα CNC) (σελ. 157)

Ερώτηση: 7. Write the comparative degree of the adjectives or adverbs in parentheses to state the advantages of CNC machine tools over the conventional ones. 1. Cutting tools can be replaced (quickly) . 2. Even small parts can be produced (good, rapidly and economically) , and . 3. Tooling and inspection costs are (low) . 4. Tool monitoring systems guarantee (long) tool life. 5. In CNC machine tools, (much) time is spent on machining the part and (little) on loading and unloading workpieces, changing tools and making trial cuts. 6. Complex forms can be machined (easily and accurately) and . 7. CNC machine tools are (flexible, versatile) and than the conventional ones. 8. Because of the simplicity of the new workholding devices (few) jigs, fixtures or chucks are required. 9. CNC machine tools guarantee (high) production rates. 10. A metal parts producing industry which uses CNC machine tools efficiently can gain a (big) ___ share of the market.

Απάντηση:

1. more quickly.
1. better, more rapidly and more economically.
1. lower.
1. longer.
1. more ... less.
1. more easily and more accurately.
1. more flexible and more versatile.
1. fewer.
1. higher.
1. bigger.

Σύνοψη: (ενδεικτική) Κάθε επίθετο/επίρρημα μπαίνει στον συγκριτικό βαθμό, όπως παραπάνω.

Odd-one-out (λεξιλόγιο NC/CNC) (σελ. 158)

Ερώτηση: 8. Odd-one out. 1. revolve, rotate, turn, recycle. 2. additional, flexible, versatile, adjustable. 3. reduce, eliminate, increase, minimize. 4. monitor, identify, inspect, check. 5. proceed, achieve, fulfill, succeed. 6. option, collection, choice, preference.

Απάντηση:

1. recycle (τα άλλα τρία σημαίνουν «περιστρέφομαι»).
1. additional (τα άλλα τρία σημαίνουν «προσαρμόσιμος/ευέλικτος»).
1. increase (τα άλλα τρία σημαίνουν «μειώνω/εξαλείφω»).
1. identify (τα άλλα τρία σημαίνουν «παρακολουθώ/ελέγχω»).
1. proceed (τα άλλα τρία σημαίνουν «πετυχαίνω/ολοκληρώνω»).
1. collection (τα άλλα τρία σημαίνουν «επιλογή»).

Σύνοψη: (ενδεικτική) Η λέξη που δεν ταιριάζει σε κάθε ομάδα (το νόημά της διαφέρει από τις άλλες τρεις) είναι, όπως παραπάνω: recycle, additional, increase, identify, proceed, collection.

Συνώνυμα και αντώνυμα (λεξιλόγιο NC/CNC) (σελ. 158)

Ερώτηση: 9. Make pairs of: A. Synonyms: require, aim, rapid, reduce, eliminate, complex, characteristic, expensive, equip, locate, force, worn / supply, dull, complicated, power, costly, demand, intend, place, minimize, decrease, feature, quick. B. Antonyms: easy, rapid, conventional, reduce, simple, remove, same, dull / slow, different, complicated, modern, place, sharp, increase, difficult.

Απάντηση:

A. Synonyms: require—demand, aim—intend, rapid—quick, reduce—decrease, eliminate—minimize, complex—complicated, characteristic—feature, expensive—costly, equip—supply, locate—place, force—power, worn—dull.
B. Antonyms: easy—difficult, rapid—slow, conventional—modern, reduce—increase, simple—complicated, remove—place, same—different, dull—sharp.

Σύνοψη: (ενδεικτική) Τα ζεύγη συνωνύμων (Α) και αντωνύμων (Β) σχηματίζονται όπως παραπάνω, με βάση το λεξιλόγιο της ενότητας.

Κριτήρια αξιολόγησης:

Το «remove» ανήκει μόνο στα αντώνυμα (remove — place)· στα συνώνυμα το eliminate ζευγαρώνει με το minimize και το reduce με το decrease.

Σύνδεση αιτίας-αποτελέσματος (CNC πλεονεκτήματα) (σελ. 158)

Ερώτηση: 10. EXPRESSING CAUSE/REASON → RESULT/CONSEQUENCE. Join the sentences to express cause/reason → result/consequence. 1. More operations can be performed on a workpiece in only one setup. CNC machine tools have greatly increased production rates. 2. Machining centres can use up to 6 axes of motion. They can produce more complex forms. 3. CNC machine tools can automatically select speed and feed. They guarantee longer life of the cutting tools. 4. NC machines are characterized by accuracy and flexibility. They reduce the amount of scrap. 5. CNC machines use chip conveyors. They don't have to stop operating to remove chips. 6. The two turrets can machine a part simultaneously. Production time is greatly reduced. 7. The new tool-changing devices can change a tool in less than 6 sec. Non-productive time has been drastically decreased. 8. The new jigs and fixtures hold the workpieces more securely. The quality of the produced parts has been improved. 9. CNC machine tools operate automatically. Fewer operators are needed to attend their performance. 10. The new chucks provide higher gripping forces and accuracy. Turning centres can meet the demand for heavier metal removal rates and higher spindle speeds.

Απάντηση:

1. Because more operations can be performed on a workpiece in only one setup, CNC machine tools have greatly increased production rates.
1. Since machining centres can use up to 6 axes of motion, they can produce more complex forms.
1. As CNC machine tools can automatically select speed and feed, they guarantee longer life of the cutting tools.
1. NC machines are characterized by accuracy and flexibility, so they reduce the amount of scrap.
1. CNC machines use chip conveyors, so they don't have to stop operating to remove chips.
1. Because the two turrets can machine a part simultaneously, production time is greatly reduced.
1. Since the new tool-changing devices can change a tool in less than 6 sec, non-productive time has been drastically decreased.
1. As the new jigs and fixtures hold the workpieces more securely, the quality of the produced parts has been improved.
1. Because CNC machine tools operate automatically, fewer operators are needed to attend their performance.
1. Since the new chucks provide higher gripping forces and accuracy, turning centres can meet the demand for heavier metal removal rates and higher spindle speeds.

Σύνοψη: (ενδεικτική) Κάθε ζεύγος προτάσεων ενώνεται με σύνδεσμο αιτίας (because/since/as) ή αποτελέσματος (so), όπως παραπάνω.

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VOCATIONAL LANGUAGE LEARNING COURSEBOOK FOR MECHANICAL ENGINEERING TECHNICIANS Β ΕΠΑΛ

Λύσεις — Κεφάλαιο 6: Machine Tools (σελ. 127-158) – VOCATIONAL LANGUAGE LEARNING COURSEBOOK FOR MECHANICAL ENGINEERING TECHNICIANS Β ΕΠΑΛ