What Are The Parts Of Jaw Crushers?

Jaw crushers are essential machines in mining, quarrying, and recycling, designed to break down large rocks into smaller, manageable pieces. Understanding their key components helps in maintenance, troubleshooting, and efficient operation. Below are the main parts of a jaw crusher and their roles:

1. Fixed Jaw Plate (Stationary Die)

Function: Acts as the anvil, providing a rigid surface against which the rock is crushed.
Material: Made of high manganese steel or other wear-resistant alloys.
Maintenance: Needs periodic replacement due to abrasion.

2. Movable Jaw Plate (Swing Jaw Die)

Function: Moves in an elliptical motion, pressing material against the fixed jaw for crushing.
Design: Often has replaceable teeth or liners to extend lifespan.
Adjustment: Can be reversed or rotated to even out wear.

3. Pitman (Eccentric Shaft Assembly)

Function: Transmits power from the motor to the movable jaw, creating the crushing action.
Components:
Eccentric shaft – Generates the elliptical motion.
Bearings – Support the shaft and reduce friction.
Maintenance: Requires regular lubrication to prevent overheating.

4. Toggle Plate (Safety Plate)

Function:
Acts as a safety mechanism—breaks if uncrushable material enters, protecting other components.
Helps adjust the crusher’s discharge opening.
Material: Typically made of cast iron or steel.

5. Flywheel

Function:
Stores energy to ensure smooth operation and reduce power fluctuations.
Balances the crusher’s motion for consistent crushing force.
Design: Heavy-duty cast iron or steel wheel.

6. Cheek Plates (Side Liners)

Function: Protect the crusher’s frame from wear caused by rock abrasion.
Material: Often made of AR (abrasion-resistant) steel.

7. Adjustment System (Wedge or Hydraulic)
Function: Controls the size of the output material by adjusting the gap between the jaws.
Types:
Mechanical wedges – Manual adjustment.
Hydraulic systems – Allows quick adjustments without stopping the crusher.

8. Frame (Crusher Body)
Function: Provides structural support for all components.
Material: Heavy-duty steel construction for durability.

9. Discharge Opening (CSS – Closed Side Setting)
Function: Determines the final crushed product size.
Adjustment: Modified via the toggle system or hydraulic controls.

10. Motor & Drive System
Function: Powers the eccentric shaft via belts, gears, or direct drive.
Maintenance: Check belts for wear and proper tensioning.

How These Parts Work Together
1.The motor drives the eccentric shaft via the flywheel, moving the swing jaw.
2.Rock enters the crushing chamber and is compressed between the fixed and movable jaw plates.
3.Crushed material exits through the discharge opening, controlled by the toggle plate or hydraulic adjustment.
4.Cheek plates protect the frame, while the toggle plate acts as a fail-safe.

Maintenance Tips for Longevity
✔ Inspect jaw plates regularly for wear and replace as needed.
✔ Lubricate bearings and eccentric shaft to prevent overheating.
✔ Check toggle plates for cracks or deformation.
✔ Monitor discharge settings to ensure consistent product size.
✔ Clean the crushing chamber to avoid material buildup.

Understanding the parts of a jaw crusher helps operators maintain efficiency, reduce downtime, and extend the machine’s lifespan. Regular inspections and timely replacements of wear parts (like jaw plates and toggle systems) are crucial for optimal performance.