1. Sandvik Construction A world leader in Construction Module 2b
How machinery factors affecting crusher performance
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2. Safety first Safety is our top priority Protective Equipment
Emergency Number
Emergency Exit
Assembly Point
Alarm 2
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3. Crushing concepts Machinery factors What are we about to examine
The major machinery influences on crusher performance, which are
setting
throw
chamber volume
speed
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4. Crushing concepts Machinery factors Control features
Jaws
Cone
HSI
VSI
Chamber
Limited by plate profile
Various & many
Limited by position of curtains and setting on bottom curtain.
Different depth rotors
Throw
Limited X
Speed
Yes
Setting
Other
Nip Angle
Automation
Bi-Flow operation
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5. Crushing concepts Machinery factors Jaw crushers Control features
Nip Angle
Width
Gape
Flywheel speed
What features can be changed?
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Features of the Jaw Crusher this relates to all Jaw Crushers
Nip Angle this is important with regards to the flow of material when crushing because if the nip angle is wrong then material will bounce back up rather than be crushed
Gape and Width are impotant with regards to the top size of material that we can accept

6. Crushing concepts Machinery factors Jaw crushers Control features
What machine factors can be used to adjust the performance of a jaw crusher?
Closed side setting (C.S.S.)
Jaw plate tooth profiles
Speed
Stroke
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7. Crushing concepts Machinery factors Jaw crushers Manual setting adjustment
Manual shim-type setting regulation
Hydraulically assisted shim-type setting regulation
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8. Crushing concepts Machinery factors Jaw crushers Hydraulic wedge setting adjustment
Hydraulic Setting Wedge System = =
The setting is adjusted with the help of wedges. Adjustment is carried out “automatically” simply at the push of a button.
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Hydraulic Setting Regulation Wedge systems is available on the QJ330, although there is a wedge system available on all of the Mid Range mobiles for setting regulations.
The depth of the Jaw box is important with regards to mobiles.
You need to be careful on the depth because we want to make the mobile until as low in height as possible for transport but the bigger depth of Jaw Box the better the material reduction due to the fact that the material spends longer in the crushing chamber.

9. Crushing concepts Machinery factors Jaw crushers Jaw tooth profiles
Coarse Corrugated (CC)
Sharp Teeth (ST)
Heavy duty (HD)
Designed to give high performance and low operating costs
All jaw plates are reversible
Wide Teeth (WT)
Corrugated (C)
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10. Crushing concepts Machinery factors Jaw crushers Speed
The number of compression and the distance material will fall is determined by the speed. We will examine this later in this module relative to cone crushers
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11. Crushing concepts Machinery factors Jaw crushers Throw Toggle plate angle
Steeper angle resulting in larger horizontal movement
Gap through which the material passes
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12. Crushing concepts Machinery factors Jaw crushers Throw Toggle plate angle
Adjustable stroke by changing the position of the toggle block holder.
Dry rolling toggle (low maintenance)
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13. Crushing concepts Machinery factors Cone crushers Chambers
All other parts in the crusher are ”only” there to hold the chamber in place or to create movement of the mantle.
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14. Crushing concepts Machinery factors Cone crushers Why so many chambers?
All crushing starts
with the chamber!
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15. Crushing concepts Machinery factors Cone crushers Why so many chambers
Which loaded EC chamber will produce the best performance
Should both feeds be fed to the same chamber?
Consider volumetric capacity
Consider mechanical advantage
Consider wear profiles
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16. Each eccentric revolution means a crushing stage
Crushing concepts Machinery factors Cone crushers Speed
Eccentric throw m mg N mN
Travel
length
Each eccentric revolution means a crushing stage
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Eccentric speed rpm
H2800=395
H3800=360
H4800=320
H6800=290
H7800=280
H8800=230

17. Crushing concepts Machinery factors Cone crushers Speed
There are a number of steps as material passes through the chamber
When the falling stone is caught, it is trapped and to some degree pushed upwards.
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18. Crushing concepts Machinery factors Cone crushers Speed
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19. Crushing concepts Machinery factors Cone crushers Speed v Capacity
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20. Crushing concepts Machinery factors Cone crushers Speed Practice proves theory
Point go remember
Higher speed: Lower throughput Finer product Improved product quality.
Lower speed: Higher throughput Coarser product Poorer product quality.
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21. Crushing concepts Machinery factors Cone crushers CSS Consequence map
C.S.S. reduction
Smaller volume in the crushing chamber
Higher pressure
Lower capacity
Risk of packing
Improved shape
More power
Higher energy consumption
Finer product
Higher net capacity
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22. Crushing concepts Machinery factors Cone crushers Motion pattern
OSS CSS OSS
Concave
CSS followed 1800 later by OSS
Mantle
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23. Crushing concepts Machinery factors Cone crushers Throw Altering the eccentric throw
Eccentricity
Eccentricity
Mainshaft
Eccentric bush
Eccentric
Increasing the eccentric throw-more energy to the material-more capacity-more nett product
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24. Crushing concepts Machinery factors Cone crushers Increased throw Larger avarage volume
Eccentric throw
Increased average chamber volume
Small throw
Large throw
Increased throw resulting in increased chamber volume results in
higher capacity
more stones in the chamber to compress
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25. Crushing concepts Machinery factors Cone crushers Throw alteration Consequence map
Throw increased
More crushing
stone-against-stone
Packing risk
Higher capacity
More power needed
Higher power
consumption
Improved shape
Higher net capacity
Larger
average setting
Higher flow
Higher torque
Increased
compression
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26. Crushing concepts Machinery factors Cone crushers Larger throw larger crushing force
F1+F2 F3 a
Reaction Force F1
Hydroset pressure
p is proportional to Crushing Force F
Reaction Force F2
Area of Piston: A
Reaction Force F3
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27. Crushing concepts Machinery factors Cone crushers Relationship between power & pressure
Max permitted
Packing
Fine crushing
Hydraulic pressure
Coarse crushing
Power
Max permitted
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28. Crushing concepts Machinery factors Cone crushers Take home message
Best results are achieved when the optimum chamber is fitted to the crusher.
The optimum throw has a major influence on obtaining best results
1&2 are volumetric issues and may well determine the utilisation of the crusher --- remember all crushers work best when continuously choke fed
The crusher setting has an effect on both volume and reduction.
Is the feed condition correct—have you removed the risk of packing
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29. Crushing concepts Machinery factors Cone crushers Summary
The work done in a crusher is affected by
Machinery factors such as
setting
throw
chamber volume
speed
Work done(energy)=volume x toughness x reduction ratio
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30. Crushing concepts Machinery factors Cone crushers Summary Work done
Machinery factors such as
setting
throw
chamber volume
speed
Material factors such as
toughness.
feed size---product size.
particle size distribution and specific gravity---bulk density---volume crushed.
feed shape---moisture---clay content--- flowability.
Work done(energy)=volume x toughness x reduction ratio
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31. Crushing concepts Machinery factors Take home message
All crushers have a volumetric and a mechanical limit
Toughness of material, feed material particle size analysis, volume and reduction ratio all play their part in the ability of the crusher to perform the duty over an acceptable lifecycle.
If any combination of these factors overstress the mechanical capability of the crusher (demands too much energy from the motor) it will be necessary to reduce the influence of another.
Eg. The demand for greater throughput at the expense of reduction.
Work done(energy)=volume x toughness x reduction ratio
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32. Sandvik Construction A world leader in Construction