The main difference between Double and Single Toggle Jaw Crusher is the location of the eccentric shaft. In double toggle machines, the eccentric shaft is located behind the swing jaw, and the swing jaw is pivoted separately from another shaft. On the other hand, the swing jaw of single toggle jaw crusher is pivoted directly on the eccentric shaft. This helps the single toggle crusher achieve a more aggressive crushing stroke, and hence the apparent popularity.
That said, Double Toggle Jaw Crushers have been hugely successful in the past. They offer a better operational economy as compared to Single Toggle Jaw Crushers. The jaw plate consumption is less by almost 4 times and the percentage of fines generated is also smaller.
Double toggle jaw crushers, however, are heavier and require much larger headroom than single toggle machines. They therefore are generally unsuitable for mobile operations. To add to that, they accept smaller feed size and have a much lower throughput. They are also prone to choking and bridging while crushing. In contrast, single toggle jaw crushers have fewer moving parts and aggressive crushing strokes. Being technologically superior, they have mostly replaced the double toggle jaw crushers.
DOUBLE TOGGLE JAW CRUSHER
In a Double Toggle Jaw Crusher the eccentric shaft is located behind the swinging jaw. This protects the eccentric shaft and bearings from the shock loading. Two toggle plates from either side of the pitman are respectively connected to the back of the crusher and the swing jaw.
As the eccentric shaft rotates, reciprocation of the pitman causes to and fro swinging door motion of the moving jaw. This creates a powerful compression in the crushing chamber. Thus a double toggle jaw crusher is more effective for crushing very strong abrasive rocks. Since there is no other plane of motion, there is lesser wear and tear of the jaw plate but also lesser throughput.
SINGLE TOGGLE JAW CRUSHER
Single toggle jaw crusher is a modern design which is lighter, has greater throughput and is less expensive than a double toggle jaw crusher. The eccentric shaft in this design acts as the pivot as well as the actuator for the reciprocation. The toggle plate directly connects the back of the crusher to the swinging jaw.
The single toggle jaw crusher has fewer bearings and shafts as compared to a double toggle jaw crusher. It has more planes of movement of the swinging jaw (Hinge door movement plus vertical up and down movement) which leads to higher throughput. On the downside, it produces more fines, and has a higher jaw plate consumption.
|SINGLE TOGGLE JAW CRUSHER||DOUBLE TOGGLE JAW CRUSHER|
|Uses one toggle plate.||Uses two toggle plates.|
|Less expensive||More expensive|
|Lesser number of parts||More number of parts|
|Higher throughput||Lower throughput|
|Crushing stroke has vertical movement along with to and fro motion||To and fro swinging door motion of the crushing stroke|
|More wear and tear of jaw plates||Less wear and tear of jaw plates|