4. Answer the questions to the text:

1. What is a crusher?

2. Where are crushers primarily used?

3. What types of crushers do you know?

4. What is crushing?

5. What kind of crushers is most reliable in use?

6. What is the difference between the crushers and the mill?

7. What is crusher classification based on?

5. Match the words to make up possible word combinations:

1) crushing	a) material	1)
2) rock	b) mix	2)
3) raw	c) surface	3)
4) solid	d) production	4)
5) rotating	e) chamber	5)
6) higher	f) crusher	6)
7) metal	g) dust	7)
8) cone	h) speed	8)

6. Try to put these words in the right order and make a sentence:

1. A crusher is / to reduce / smaller rocks / a machine designed / into / large rocks.

2. Crushers are / material / particle size / used / to reduce.

3. Foreign objects / a crusher / can cause / damage to /extensive /.

4. Each crusher is /with /raw material /a certain maximum size of / designed to work.

5. The raw material / delivered to /by dump trucks /usually / is / the primary crusher's hopper.

6. Each crusher / of raw material / to work / a certain maximum size / is designed / with /.

7. Crushers / which / are machines / to break or compress / materials / use a metal surface /.

7. Say if the statement is true or false. If the statement is false give the correct answer:

1) A crusher is a machine designed to reduce large rocks into smaller rocks.
2) For the most part advances in crusher design have moved rapidly.
3) Crushers are used to reduce particle size enough so that the material can be processed into finer particles in a grinder.
4) Crushing stages are followed by milling stages if the materials need to be further reduced.
5). Foreign objects can cause extensive damage to a crusher.
6) The raw material is usually delivered to the secondary crusher's hopper by dump trucks.
7) Jaw crushers have remained virtually unchanged for seventy years.

8. Read the following text. Retell it to a partner:

Hydraulic Cone Crusher

HP Series of highly efficient Hydraulic Cone Crusher is a world-level cone crusher introduced with the up-to-the-minute technology of Germany. The cone crusher not only improves the production capacity and crushing efficiency, but also widens applying area, hardness range of materials from limestone to basalt. It has a great crushing performance in the work of medium-size crushing, fine crushing and super fine crushing.

The crusher is the improved type of spring cone crusher and can be used to replace ordinary hydraulic cone crusher in the field of mining and construction. It is the most ideal equipment for large stone crushing factory and mining industry.

The performance of ordinary hydraulic cone crusher acts as the reference for the performance of HP series of cone crusher. As a composing unit of the production line, its performance can be influenced by other units like feeder, belt conveyor, vibrating screen, motor, transmission part and hopper, etc.