What are the differences in shock absorption performance between rubber casters of different hardness?

Relationship between Rubber Caster Hardness and Shock Absorption Performance

The shock absorption performance of rubber casters is primarily determined by Shore A hardness. Hardness modulates vibration transmission intensity by affecting elastic deformation, energy absorption, and rebound resilience.

Low Hardness (50A-65A): Ultimate Shock Absorption

Features: Flexible molecular chains allow for significant compression deformation of 30%-50%, effectively absorbing energy through physical cushioning, and achieving a vibration transmission rate of <20%.

Effects: Excellent filtering of low-frequency vibrations (<10Hz), reducing vibration amplitude by 60%-70%, and achieving low noise levels (≤50dB).

Limitations: Weak load capacity (≤150kg per wheel), prone to permanent deformation, and poor wear resistance.

Applications: Light loads such as precision instruments and fragile items.

Medium Hardness (65A-80A): Balances shock absorption and durability.

Features: Deformation range of 15%-30%, balancing elastic cushioning and shape recovery, with a vibration transmissibility of 30%-50%. Excellent fatigue resistance.

Effects: Effectively filters both low- and medium-frequency vibrations, reducing vibration amplitude by 40%-50%, with moderate noise levels (55-65 decibels).

Advantages: Increased load capacity (150-300 kg per wheel), superior wear resistance to low-hardness versions.

Applications: General medium-load applications, mixed indoor and outdoor flooring.

High Hardness (80A-95A): Emphasizes support.

Features: Strong molecular chain rigidity, deformation range of only 5%-15%, primarily transmitting vibrations through the wheel body, with a transmissibility of >60%.

Effects: Weak shock absorption, only reducing vibration amplitude by 10%-30%, with noticeable noise levels (65-75 decibels), and a tendency to transmit high-frequency vibrations.

Limitations: Poor shock absorption performance.

Applicable: Heavy loads (300-500kg per wheel), rough-surface industrial applications, where shock absorption is less important.

Key Principles:

Shock absorption performance decreases linearly with increasing hardness: Low hardness achieves ultimate shock absorption through "large deformation energy absorption"; medium hardness offers balanced performance; high hardness sacrifices shock absorption in exchange for high load capacity and wear resistance.

Temperature Effect: Low temperatures harden low-hardness rubber, reducing shock absorption; high temperatures soften high-hardness rubber (slightly improving shock absorption in the short term, but susceptible to long-term aging).

Rubber Type: At the same hardness, natural rubber offers slightly better shock absorption but poorer weather resistance; EPDM offers superior outdoor stability.

Choice Key: A trade-off must be made between shock absorption, durability, and load capacity, finding the optimal balance based on vibration intensity, equipment sensitivity, and load requirements.