Е. С. Закирова, П. А. Красавин Английский язык для технических вузов


Exercise 24. Ask questions and use the words in italics in your answers. The



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Exercise 24. Ask questions and use the words in italics in your answers. The 
words in brackets will help you.
1. A metal workpiece is placed 
in a die
(where). 2. Heated liquid material 
is usually poured 
into a mold
(where). 3. Dies must be 
precisely 
designed (how). 
4. Dies should withstand
 tremendous forces and pressure
(what). 5. 
In the end of 
the operation
the flash is removed (when).
Exercise 25. Read the following dialogue, sum up the information and act out a 
similar dialogue.
FORGING
A.: Do you know what forging is?
B.: Sure. Forging is one of the oldest known metalworking processes. Tradi-
tionally, many metal tools were made by heating iron bars in a fire called a 
forge, and then they were worked or shaped by hammering it.
A.: Absolutely. Forging was performed by a smith using hammer and anvil. 
It is still in use though nowadays it is done either with modern presses or 
with hammers powered by compressed air, electricity, hydraulics or steam.
B.: I agree with you. Forging has lived over centuries to become a facility with 
engineered processes, production equipment, raw materials and products 
to meet the demands of modern industry.
A.: I wonder if there really exist ‘cold’, ‘warm’ or ‘hot’ forging. 
B.: You see, some metals may be forged cold, but iron and steel are almost 
always hot forged.
A.: Are there any advantages of ‘hot’ forging?
B.: Hot forging prevents the work hardening that would result from cold forg-
ing, which would increase the difficulty of performing secondary machin-
ing operations on the piece. Are you aware of the fact that forged parts 
usually require further processing to achieve a finished part?
A.: Yes, I am. But I know that work hardening may be desirable in some cir-
cumstances.
B.: Then other method of hardening the piece is used, such as heat treating
which is generally more economical and more controllable. 
A.: So, I see, engineers have to choose the type of forging to serve the given 
purpose.


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