Quick Reference Guide to Common Failures of Jack Shock-Absorbing Rubber Blocks
Jack shock-absorbing rubber blocks are critical components for cushioning, vibration reduction, and load distribution. However, improper use, environmental exposure, or material degradation can lead to a variety of common failures. This quick reference guide summarizes typical issues, their causes, and preventive measures to facilitate rapid troubleshooting.
1. Hardening or Loss of Elasticity
Symptoms: Rubber feels stiff, less compressible, or brittle.
Causes: Thermal aging, UV or ozone exposure, prolonged high temperatures, or chemical attack.
Prevention: Use temperature- and UV-resistant materials, store blocks in a cool, dark environment, and avoid chemical contact.
2. Cracking and Surface Splitting
Symptoms: Visible cracks, often radial or tortoise-shell patterns.
Causes: Fatigue from repeated cyclic loading, low-temperature brittleness, or over-curing during vulcanization.
Prevention: Select proper hardness, avoid overloading, use low-temperature-resistant rubbers, and inspect regularly.
3. Swelling or Softening
Symptoms: Bulging, reduced load-bearing capacity, and softer surface.
Causes: Contact with incompatible oils, fuels, solvents, or other chemicals.
Prevention: Choose chemically compatible materials (e.g., NBR for oil resistance) and isolate rubber blocks from harmful substances.
4. Delamination or Detachment
Symptoms: Rubber block separates from bonded metal plate or shifts during use.
Causes: Poor adhesion during manufacturing, incorrect bonding techniques, or mechanical overload.
Prevention: Follow manufacturer bonding guidelines, use appropriate adhesives, and avoid excessive loading.
5. Deformation or Bulging
Symptoms: Visible distortion, permanent compression, or uneven surfaces.
Causes: Overloading, incorrect hardness selection, or prolonged static stress.
Prevention: Match hardness and dimensions to load requirements, avoid exceeding rated capacities, and monitor stress distribution.
6. Unusual Noise During Operation
Symptoms: Squeaking, popping, or other abnormal sounds.
Causes: Hardening, misalignment, insufficient lubrication in contacting surfaces, or trapped air pockets.
Prevention: Ensure proper installation, maintain lubrication if required, and replace aged or damaged blocks.
7. Accelerated Fatigue or Shortened Service Life
Symptoms: Premature wear, cracking, or permanent deformation under normal usage.
Causes: Material aging, environmental stressors, overloading, or poor design.
Prevention: Select appropriate materials, protect from environmental factors, distribute load evenly, and conduct regular inspections.
Conclusion
By understanding the common failure modes of jack shock-absorbing rubber blocks—such as hardening, cracking, swelling, delamination, deformation, noise, and fatigue—operators can implement preventive measures including proper material selection, correct installation, environmental protection, and regular maintenance. Quick detection and timely intervention help maintain operational safety and extend service life.
References
Gent, A. N. Engineering with Rubber: How to Design Rubber Components. Hanser Publishers, 2012.
ASTM D573 – Standard Test Method for Rubber—Deterioration in an Air Oven.
Lake, G. J. “Fatigue and Fracture of Elastomers.” Rubber Chemistry and Technology, 2000.
ISO 7619-1 – Rubber, Vulcanized or Thermoplastic — Determination of Indentation Hardness.
ISO 2230 – Rubber Products—Guidelines for Storage.
