Brittleness of Pads in Low-Temperature Environments
Pads used in jacks and lifting equipment are typically made from rubber, polyurethane, or elastomeric materials. Exposure to low temperatures can significantly alter their mechanical properties, leading to brittleness and reduced performance.
1. Causes of Pad Brittleness in Low Temperatures
Material Hardening: Elastomers and polyurethane stiffen at low temperatures, losing flexibility.
Glass Transition: Some polymers reach their glass transition temperature (Tg) in cold conditions, becoming brittle and prone to cracking.
Environmental Stress: Combined effects of low temperature and load can accelerate micro-crack formation.
Aging: Long-term exposure to low temperatures can exacerbate natural aging and embrittlement.
Inadequate Material Selection: Pads not specifically formulated for low-temperature use are more susceptible to brittleness.
2. Effects of Brittleness
Cracking and Fracture: Brittle pads are more likely to crack or chip under load.
Reduced Load Distribution: Loss of elasticity compromises the pad’s ability to evenly distribute weight, increasing stress on the jack and load.
Slippage and Instability: Stiff, brittle pads may slip on the contact surface, reducing operational safety.
Shortened Service Life: Repeated loading in low temperatures accelerates wear and structural damage.
3. Preventive Measures
Use Low-Temperature-Resistant Materials: Select pads made from elastomers or polyurethane compounds rated for cold environments.
Avoid Sudden Impact Loads: Apply loads gradually to reduce stress on stiffened pads.
Regular Inspection: Check for signs of hardening, cracks, or brittleness and replace pads when necessary.
Proper Storage: Store pads in controlled environments before use to minimize pre-exposure to extreme cold.
Surface Protection: Apply coatings or lubricants compatible with low temperatures to reduce friction and stress.
4. Conclusion
Low-temperature environments can cause pads to become brittle due to material hardening, glass transition, and environmental stress. Selecting appropriate materials, controlling load application, and regular inspection are essential to maintaining pad performance and operational safety in cold conditions.
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 D746 – Standard Test Method for Brittleness Temperature of Plastics and Elastomers by Impact.
ISO 2921 – Rubber, Vulcanized or Thermoplastic — Determination of Temperature-Rebound Resilience.
ASTM D2240 – Standard Test Method for Rubber Property—Durometer Hardness.
