Study the key words to the crossword from Unit III

Noun Verb Adjective Adverbial Modifier

property vary alloying with iron content

steel depend upon chemical at high temperature

solution contain solid normally

carbon produce high by cooling

resistance have rapid in plants

Additional Activities: Miscellaneous

18. Engineer tested. Do you believe …

1) that compressed air generated from rotary screw compressors and proper clean air treatment is up to 10,000 times cleaner than the air webreathe?

2) that air volume increases (expands) as temperature increases?

3) that compressed air is the fourth utility in an industrial plant, after electricity, gas and water?

19. Study the compressor refrigerator schematic, operation and construction. Discuss the information in dialogues. How do you see the compressor refrigerator in the future?

Evaporator – испаритель, motor – двигатель/мотор, condenser (cooler) – конденсатор, compressor – компрессор, cooling fin- охлаждающее ребро

The most common refrigeration unit is the compressor type.

• A compressor, which is found at the base of the fridge, contains a gas refrigerant. A refrigerant is a liquid that can evaporate at very low temperatures. 'Freon 12' and liquid ammonia are examples of refrigerants that have been used in refrigerators. A small motor attached to the compressor forces the gaseous refrigerant into the condenser.

• The condenser cools and condenses the gas refrigerant back into a liquid. A condenser is visible on the outside of the back of a refrigerator, attached to which are a number of cooling fms, which help to cool the refrigerant by conducting heat away from the condenser.

• The refrigerant, which is now in a liquid state, passes into the evaporator, the coldest part of the fridge. Here the refrigerant evaporates by drawing heat from the fridge cabinet. In this way, the cabinet is cooled.

• The gaseous refrigerant is then pumped back to the compressor, where the cycle will begin again.

• A thermostat is fitted, which disconnects the electricity when the cabinet is cool enough and restarts the motor when temperatures rise.

Дата добавления: 2014-12-26