Correct feeding operation points of jaw crusher

Standard feeding is the core premise to stabilize output, reduce cavity blockage, lower abnormal wear of jaw plates, toggle plates and bearings, and avoid overload shutdown. Improper feeding is one of the top causes of frequent crusher failures.

1. Feed material requirements

Strictly control feed size: The maximum lump size shall not exceed 80% of the feed opening width. Oversized stones easily lead to jamming and unilateral overload.
Remove tramp iron and uncrushable objects: Install magnetic separator or iron remover on the feeding belt. Iron blocks, drill bits, steel scraps must be intercepted in advance to prevent toggle plate breakage.
Control material humidity and viscosity: Wet, sticky clay-rich materials are prone to packing inside the crushing chamber. Reduce feeding volume properly when moisture is high.
No mixed fine powder excess: Too much fine powder in raw ore will reduce crushing efficiency and cause material sliding, affecting nip effect.

2. Feeding position and distribution

Central feeding: Materials should fall to the middle of the feed opening, avoid one-sided feeding. Unilateral feeding creates eccentric load, accelerates jaw plate uneven wear and imposes extra lateral force on toggle plate.
Do not stack materials above the fixed jaw or movable jaw side alone.
Keep material spread evenly across the crushing width as much as possible.

3. Feeding speed and feeding volume control

Feed continuously and uniformly, not intermittently or surgingly. Sudden surge feeding causes instant overload and triggers protective shutdown.
Do not overfill the crushing cavity. The material pile shall not be higher than the jaw guard plate. Overfilling will block material discharge and raise crushing resistance.
Match feeding rate with the crusher’s actual handling capacity and downstream conveyor speed. Adjust feeder frequency in time when discharge condition changes.
Do not run the jaw crusher with empty cavity for a long time, and avoid sudden full load feeding from idle state.

4. Feeder & chute management

Keep the feeding chute unobstructed, regularly clean sticky buildup on chute walls.
Check the vibrating feeder or belt feeder for stable operation; fix feeder deviation in time.
The drop height of material should be reasonably controlled. Excessive drop impact brings shock load to the crusher and causes loose bolts.
Wear liners on the impact position of the chute to reduce impact damage.

5. Operation sequence & cooperation rules

Start the jaw crusher first, wait until the machine reaches stable rated speed, then start feeding equipment.
Stop feeding first before shutting down the crusher. Only stop the main machine after all materials inside the cavity are completely discharged. Never shut down with full cavity.
Observe current, vibration and discharge status during feeding. If current surges sharply or abnormal noise appears, stop feeding immediately for inspection.

6. Special condition handling

When blockage occurs: Stop feeding first, cut off power, then clean the blocked materials. Do not poke materials with heavy tools while the machine is running.
After toggle plate replacement or maintenance: Feed with small load first, run for a period of time and check operation status before restoring normal feeding capacity.
When discharge opening is adjusted: Re-match the feeding volume accordingly. Smaller discharge setting needs lower feeding rate.

7. Daily inspection items related to feeding

Regularly check the wear of feed hopper, chute lining and jaw guard.
Check whether the iron removal device works normally.
Confirm that the feeding alarm, current interlock protection function is available.

Summary

The key principles of jaw crusher feeding: proper lump size, central even feeding, continuous stable quantity, no tramp iron, stop feeding before shutdown. Good feeding operation can greatly cut down failures such as toggle plate fracture, cavity blockage, uneven jaw plate wear and overload trip.