Task 9. Use the words in the box to complete the text. Use each word only once.
Welded load wheel chain also has 3 times as much 1)________ absorption capability as a wire 2)_______ of equal static tensile strength. As a result, wire rope of equal impact 3)_________ costs much more than load wheel chain. Since average wire rope life in a hoist is only about 5 percent of the life of 4)________, overall economics are greatly in favor of chain for hoisting purposes. Another widespread use of 5)________ link chain is in conveyor applications where high loads and moderate speeds are encountered. As contrasted to link-wheel chain used in hoists, 6)_______ chain requires a longer pitch. The longer-pitch chain, in addition to being more economical, accommodates the use of shackle connectors between sections of the chain to which flight bars are attached.
Wire rope used for suspending loads is usually required to be as flexible as possible to minimize the 7)_________ of the drums or sheaves involved. Thus, a rope having six strands of 19 wires each on a hemp core is used. Extra pliable ropes made with strands of 37 wires each or eight strands of 19 wires each on a hemp core are also available but are much less 8)__________ because of the finer individual wires used. Hoisting ropes are constructed with the relative twist of the wires in the strands the reverse of the twist of the strands about the core.
Task 10. Make sentences about the materials with ‘can …, but …, can’t’, or ‘can … and … can’. The first one is done for you.
1) (bend/metal/wood) You can bend metal, but you can’t bend wood.
Task 11. A lecturer is showing a DVD of a test. Complete the description. The first one is done for you.
Hello. Now we can watch the DVD of a car crash. Here they (1) are testing(test) the material for the seatbelt. The human dummy (2) _______ (sit) in the test car. This dummy weighs 90 kilos. Here the technician (3) ______ (tighten) the nylon seatbelt around the dummy. Now the technician (4) ______ (start) the engine of the radio-controlled car.
Look at the crash in slo-mo (slow motion). The car (5) ______ (run) into the concrete block at 40 kph. The body of the dummy (6) ______ (stretch) the nylon seatbelt. And see, the dummy (7) ________ (touch) the airbag. Look carefully. Is the dummy’s face (8) _______ (strike) the front window? No, it isn’t. there is no contact with the front window.
Task 12. Underline the two correct adjectives for each material. The first one is done for you.
1) A ceramic cup is flexible/heat-resistant and hard/soft.
2) A concrete floor is rigid/flexible and brittle/tough.
3) A rubber tire is rigid/flexible and weak/strong.
4) A fiberglass window frame is heat-resistant/soft and rigid/flexible.
5) A nylon rope is rigid/flexible and strong/weak.
6) The graphite in the middle of a pencil is light/heavy and hard/soft.
7) A polycarbonate road sign is rigid/flexible and strong/weak.
8) A polystyrene coffee cup is brittle/tough and heavy/light.
Task 14. Write a short report (80-100 words) about natural materials. How do engineered materials differ from natural materials? Use the following pictures.
Task 15. Watch the video file “What Is Material Handling. Try to explain what is material handling? This video, produced by the Material Handling Industry of America and the Material Handling Equipment Distributors Association, which Fred Hill is a proud member of, does a great job of explaining exactly what material handling is and how it touches every industry and plays a pivotal role in day-to-day life.
UNIT 2. GEAR AND GEARING (Part 1)
Task 1. What is the role of gears in modern world? What types of gear can you name?
Task 2. Label the gear components on the diagram below. Use the words in the box.
Task 3. Watch the video and try to explain the main principles of a system of gears. Discuss this process with your groupmates.
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