See Article History Alternative Titles: It is the first process that most ores undergo after mining in order to provide a more concentrated material for the procedures of extractive metallurgy. The primary operations are comminution and concentration, but there are other important operations in a modern mineral processing plant, including sampling and analysis and dewatering. All these operations are discussed in this article.
The Work Index of the ore CWi F80 feed size Required reduction ratio A jaw crusher size is obtained by looking at its feed opening gape and length. Proper selection of the jaws.
Sufficient feeder capacity and width. Adequate crusher discharge area. Discharge conveyor sized to convey maximum crusher capacity. A spring loaded tension rod keeps the toggle in its seats.
For major crusher closed-side setting adjustment, the length of the front toggle is changed. The jaw crusher discharge opening is the distance from the valley between corrugations on one jaw to the top of the mating corrugation on the other jaw.
The crusher discharge opening governs the size of finished material produced by the crusher. Measure distance at bottom of jaws at the point of the crushing cycle when bottom of jaws are closest together. Turn flywheel so that counter weights are parallel with movable jaw. Adjusting the discharge side opening: Loosen nuts 4 before making adjustment.
Loosen tension if crusher is to be adjusted for finer crushing. Crusher must be adjusted when empty and stopped. Never close crusher discharge opening to less than minimum opening.
Closing crusher opening to less than recommended will reduce capacity of crusher and cause premature failure of shaft and bearing assembly. To compensate for wear on toggle plate, toggle seat, pitman toggle seat and jaws additional shims must be inserted to maintain the same crusher opening.
The setting adjustment system is designed to compensate for jaw plate wear and to change the CSS closed side setting of the jaw crusher.
The setting adjustment system is built into the back frame end. A toggle plate is fitted between an upper toggle seat and a lower toggle seat. Behind the toggle seat holder, two hydraulic cylinders can push the setting wedges inwards to decrease the discharge setting.
The moving jaw is pushed closer to the stationary jaw and when the gap between the two jaws decreases only smaller fragments of processed material are allowed to pass through.
If the hydraulic cylinders move outwards, the gap increases and larger fragments of processed material can pass through. The setting adjustment system is kept in place by a retraction arrangement with a hydraulic cylinder. Here also the toggle is keep in place by a compression spring.
Large CSS adjustments are made to the jaw crusher by modifying the length of the toggle. Again, shims allow for minor gap adjustments as they are inserted between the mainframe and the toggle block.
By design, tramp metal will shear and break the toggle to protect the machine. Sizing Jaw Crushers is done considering the maximum rock-lump or large stone expected to be crushed and also includes the TPH tonnage rate needing to be crushed.
In large open-pit mines the excavator too often dictated the max feed size of rocks going to the crusher. It will be seen that the pitman is suspended from an eccentric on the flywheel shaft and consequently moves up and down as the latter revolves, forcing the toggle plates outwards at each revolution.
The seating of the rear toggle plate is fixed to the crusher frame ; the bottom of the swing jaw is therefore pushed forward each time the pitman rises, a tension rod fitted with a spring being used to bring it back as the pitman falls. Thus at each revolution of the flywheel the movable jaw crushes any lump of ore once against the stationary jaw allowing it to fall as it swings back on the return half-stroke, until eventually the pieces have been broken small enough to drop out.
It follows that the size to which the ore is crushed. The jaw crusher is not so efficient a machine as the gyratory crusher described in the next paragraph, the chief reason for this being that its crushing action is confined to the forward stroke of the jaw only, whereas the gyratory crusher does useful work during the whole of its revolution.
In addition, the jaw crusher cannot be choke-fed, as can the other machine, with the result that it is difficult to keep it working at its full capacity— that is, at maximum efficiency.
Tables 5 and 6 give particulars of different sizes of jaw crushers. The capacity figures are based on ore weighing lb. Capacities are based on material weighing lb. They both have the same crushing speed, to R. They both break the ore by compression force.Mineral processing: Mineral processing, art of treating crude ores and mineral products in order to separate the valuable minerals from the waste rock, or gangue.
It is the first process that most ores undergo after mining in order to provide a more concentrated material for the procedures of . If the jaw crusher product increases in size, the cone crusher may become overloaded. Similarly, if the cone crusher product increases in size, the circulating load around the cone crusher will increase, consequently, increasing the load on the cone crusher and decreasing throughput.
Recently an overseas operator with more than 4 years experience was killed when a heavy jaw crusher liner plate dislodged as he was attempting to secure it. This type of accident calls attention to the need to have safe maintenance procedures for all tasks. The Right Jaw Crusher Running Procedures.
Topics: Mineral, Crusher Pages: 1 ( words) Published: August 14, Jaw crusher is a kind of stone crusher which is also rock crusher. As the name implies, crusher is used for crushing all kinds of minerals and rocks with compressive strength.
jaw crusher is not only able to be used together. HSE - Quarries - Safe operation and use of mobile jaw crushers. Oct 11, Guidance on the safe operation and use of mobile jaw crushers.
This should detail the procedures to follow in the event of a crusher stalling. Which Crusher is Right for Me. Let one of our crushing pros help you determine the best Eagle Crusher for your needs. Learn More. Products. Discover why Eagle Crusher is the one for you. Learn More. Jaw Crushers and Plants Jaw Crushers and Plants Hammermills Hammermills Impactor Track Units.