Spring buffer device maintenance skills for jaw crusher

The spring buffer (spring safety device) is an important protective component of the jaw crusher. It works with the toggle plate to prevent damage to the main machine when non-crushable foreign matter enters the crushing chamber. Proper maintenance can guarantee safety response and extend spring service life.

1. Pre-operation Daily Inspection

Check the overall appearance of the spring group: Confirm no broken spring, serious crack, permanent deformation, corrosion or rust peeling.
Inspect spring preload: Check whether the spring seats, tie rods and nuts are in place. No loose nuts, offset springs or tilted spring seats are allowed.
Check clearance: Ensure there is no serious friction between the spring and the tie rod, spring housing or adjacent structural parts.
Check dust and mud buildup: Clean stone powder, slurry and debris stuck on the spring surface. Hard deposits will cause uneven stress and early breakage.

2. Regular Inspection & Adjustment

Preload adjustment The pre-tightening force of the spring must follow the equipment manual. Too tight will lose overload protection function; too loose will cause frequent jumping of the spring seat, impact vibration and fatigue fracture. Adjust the lock nut symmetrically, keep the compression length of each spring consistent.
Dimensional check (periodic) Measure the free length of springs. If the free length is shorter than the allowable limit due to fatigue compression, replace the whole set of springs. Do not replace only one single spring in the group.
Alignment check Check the tie rod straightness. Bent tie rods will lead to uneven spring force and unilateral overload. Straighten or replace bent tie rods in time.

3. Lubrication & Anti-corrosion Maintenance

Apply anti-rust grease on the spring surface, tie rod thread and spring seat contact surface regularly. Avoid thick hard lubricant that traps dust.
After washing the crusher, drain accumulated water around the spring buffer area. Long-term moisture will accelerate spring corrosion and fatigue.
For standby spare springs, store them in dry environment with anti-rust oil, avoid stacking and extrusion deformation.

4. Abnormal Phenomenon & Troubleshooting

Continuous spring bouncing, loud impact sound: Spring preload insufficient, or toggle plate/seating damaged, foreign matter repeatedly squeezing the buffer assembly. Stop the machine for inspection.
Spring breaks frequently: Uneven preload, material oversize, frequent iron entering crushing chamber, spring material defect, or long-term corrosion fatigue.
Nut loosens repeatedly: Locking washer damaged, thread worn, vibration exceeds standard. Replace locking parts and retighten symmetrically.

5. Replacement Key Points

Lock the equipment and cut off power before disassembly. Remove materials inside crushing cavity.
Release spring preload slowly and symmetrically. Do not loosen one side nut all at once to avoid sudden ejection of components.
Use matched springs with the same model, material, free length and elastic parameter. Mixed use of different springs is forbidden.
After replacement, adjust preload to the specified value, fasten lock nuts and install lock washers. Run no-load test and check for abnormal bouncing.

6. Important Forbidden Items

❌ Do not increase spring preload blindly to eliminate vibration. It will disable the safety protection function. ❌ Do not weld damaged springs or pad steel plates to compensate for spring fatigue. ❌ Do not run the crusher with missing springs or broken springs. ❌ Donot knock the spring directly with heavy hammer during adjustment.

7. Periodic Maintenance Cycle Reference

Daily: Visual inspection, surface cleaning
Weekly: Check nut tightness, spring seat alignment
Monthly: Measure spring free length, re-coat anti-rust grease
Quarterly: Full disassembly inspection of buffer assembly, check tie rod and spring seat wear