Abnormal Vibration Reason of Jaw Crusher – Popular Science
Introduction
Excessive or abnormal vibration is one of the common warning signs of a jaw crusher. Continuous strong vibration will loosen bolts, accelerate wear of jaw plates and bearings, damage the foundation, and even cause sudden shutdown. Below is a categorized analysis of root causes and simple troubleshooting guidance.
1. Material & Feeding Related Causes
- Overfeeding or uneven feeding: Too much material stuck inside the crushing chamber, or large hard rock hitting the jaw assembly unevenly, generating impact vibration.
- Mixed uncrushable foreign objects: Iron blocks, steel bars, drill bits entering the cavity will produce sharp impact and violent vibration.
- Raw material with excessive sticky wet content: Material clings together, causes material bridging and uneven load.
2. Mechanical Assembly & Component Wear
- Loose fasteners: Foundation anchor bolts, frame connection bolts, toggle plate seat bolts, flywheel and pulley locking screws loose. This is the most frequent cause.
- Worn or damaged parts: Worn toggle plate, broken toggle plate gasket, cracked jaw holder, worn eccentric shaft bushing, bearing clearance out of tolerance.
- Unbalanced rotating parts: Flywheel or driving pulley loss of balance; weight missing after liner replacement, or uneven abrasion on flywheel.
- Eccentric shaft deformation or bent: Long-term overload leads to shaft bending, bringing periodic vibration.
3. Drive System Problems
- Misalignment between motor pulley and crusher pulley: Belt pulleys are not on the same plane, V-belts tension uneven, causing periodic shaking.
- Damaged V-belts: Aging, cracked, inconsistent length, or too tight / too loose belt tension.
- Motor itself abnormal: Motor bearing damage, rotor imbalance, motor fixed bolts loose.
4. Foundation & Installation Issues
- Poor foundation rigidity: Foundation concrete cracks, insufficient thickness, foundation sink unevenly.
- Missing or damaged shock absorption pads: Rubber shock pads under the base aging, broken or missing.
- Level deviation during installation: The crusher is not level when fixed.
5. Lubrication & Operating Condition
- Poor lubrication of eccentric shaft bearing: Insufficient lubricating oil, oil deterioration, oil contains impurities, leads to bearing heating and vibration.
- Long-term operation under overload: Frequent overload crushing makes the whole machine work beyond design load.
Quick Troubleshooting Tips
- Stop the machine immediately once strong abnormal vibration occurs; cut off power before inspection.
- First check all anchor bolts and connecting bolts for looseness.
- Check crushing chamber to rule out tramp metal jamming.
- Observe flywheel and pulley for swing and imbalance, check belt alignment and tension.
- Listen to bearing sound and check temperature to judge bearing health.
- Inspect shock pads and foundation for cracking.
Preventive Summary
Stable vibration within the design range is normal for jaw crushers. Any sudden increase in vibration amplitude must be taken seriously. Regular bolt inspection, standardized feeding, scheduled lubrication and periodic component inspection can effectively avoid long-term abnormal vibration.