Frequent Abnormal Noise from Jack Buffer Blocks: Causes and Mitigation Measures
Jack buffer blocks are designed to absorb shock, reduce vibration, and ensure stable contact between the jack and the load. Frequent abnormal noise during lifting operations is an indication of underlying mechanical, material, or installation issues. If not addressed in time, such noise may precede performance degradation or safety risks.
1. Insufficient Damping Performance
When the rubber material loses elasticity due to aging, excessive compression set, or inappropriate hardness selection, its ability to absorb vibration decreases. As a result, impact energy is transmitted directly between the jack and the load, producing knocking or creaking noises.
2. Relative Sliding at Contact Interfaces
Abnormal noise often arises from micro-slippage between the buffer block and the jack head or load surface. Low surface friction, contamination by oil or dust, or uneven contact pressure can cause intermittent stick-slip motion, generating squeaking sounds.
3. Loose or Debonded Rubber Blocks
Partial debonding or inadequate mechanical fixation allows slight movement of the rubber block under load. This relative movement leads to repeated friction or impact between the rubber and metal surfaces, producing rattling or clicking noises.
4. Excessive Load or Impact Loading
Operating the jack beyond its rated capacity increases compressive stress and deformation of the buffer block. Sudden load changes or impact forces amplify internal friction and structural response, often resulting in sharp or repeated abnormal sounds.
5. Uneven Load Distribution
Misalignment between the jack, buffer block, and load causes localized stress concentration. Uneven compression leads to differential deformation and internal rubbing, which may generate creaking or popping noises during lifting.
6. Environmental and Surface Factors
Temperature fluctuations can change rubber stiffness, increasing noise at low temperatures due to hardening. Additionally, corrosion, rough metal surfaces, or debris at the contact interface can contribute to friction-induced noise.
Preventive and Corrective Measures
To reduce abnormal noise, buffer blocks should be made from rubber materials with appropriate hardness and damping characteristics, and aging or permanently deformed blocks should be replaced promptly. Ensuring proper bonding or mechanical fixation, maintaining clean and dry contact surfaces, and avoiding overloading are critical. Correct jack alignment and smooth load application further minimize vibration and noise.
Conclusion
Frequent abnormal noise from jack buffer blocks is mainly caused by reduced damping capacity, interface slippage, loosening or debonding, excessive or uneven loading, and environmental effects. Through proper material selection, optimized installation, controlled operation, and regular maintenance, noise issues can be effectively mitigated while improving safety and service reliability.
References
Gent, A. N. Engineering with Rubber: How to Design Rubber Components. Hanser Publishers, 2012.
Lake, G. J. “Fatigue and Fracture of Elastomers.” Rubber Chemistry and Technology, 2000.
ASTM D395 – Standard Test Methods for Rubber Property—Compression Set.
ISO 10846 – Acoustics and Vibration — Laboratory Measurement of Vibration Isolation Properties of Resilient Materials.
