[ T = \frac4Z_1Z_2(Z_1+Z_2)^2 ]
For typical steel-elastomer-steel sandwich, ( T \approx 0.01 ) at normal incidence, providing 20 dB reduction. A wave pad acts as a spring-mass system. The mounted equipment (mass ( m )) sits on pads with total stiffness ( k ). The natural frequency ( f_n ) is:
| Material | Density (kg/m³) | Young’s Modulus (MPa) | Max Temp (°C) | Loss Factor @ 100 Hz | Best for | |----------|----------------|----------------------|---------------|----------------------|-----------| | Neoprene | 1200–1500 | 5–20 | 90 | 0.1 | General industrial | | EPDM | 1100–1300 | 3–15 | 120 | 0.12 | Outdoor/weather-resistant | | Silicone | 1100–1800 | 1–10 | 230 | 0.08 | High temp/cleanroom | | Polyurethane | 1100–1250 | 10–50 | 80 | 0.2 | Heavy loads, abrasion |
Vibration isolation begins at ( f > \sqrt2 f_n ). For effective isolation below 50 Hz (common for HVAC or large motors), ( f_n ) must be ≤ 5 Hz, requiring very soft pads. However, static deflection limits apply: ( \delta_static = g / (2\pi f_n)^2 ). For ( f_n = 5 ) Hz, ( \delta \approx 10 ) mm – often impractical. Thus, wave pads are typically tuned for 10–30 Hz isolation, offering a compromise between low-frequency performance and stability. Geometric features (pyramids, channels, or periodic bumps) on the pad’s surface convert longitudinal waves into slower shear waves, increasing path length and viscoelastic loss. The loss factor ( \eta ) (ratio of dissipated to stored energy per cycle) for filled elastomers ranges from 0.05 to 0.3. 3. Materials and Manufacturing Common wave pad materials and their properties:
Wave Pads May 2026
[ T = \frac4Z_1Z_2(Z_1+Z_2)^2 ]
For typical steel-elastomer-steel sandwich, ( T \approx 0.01 ) at normal incidence, providing 20 dB reduction. A wave pad acts as a spring-mass system. The mounted equipment (mass ( m )) sits on pads with total stiffness ( k ). The natural frequency ( f_n ) is: wave pads
| Material | Density (kg/m³) | Young’s Modulus (MPa) | Max Temp (°C) | Loss Factor @ 100 Hz | Best for | |----------|----------------|----------------------|---------------|----------------------|-----------| | Neoprene | 1200–1500 | 5–20 | 90 | 0.1 | General industrial | | EPDM | 1100–1300 | 3–15 | 120 | 0.12 | Outdoor/weather-resistant | | Silicone | 1100–1800 | 1–10 | 230 | 0.08 | High temp/cleanroom | | Polyurethane | 1100–1250 | 10–50 | 80 | 0.2 | Heavy loads, abrasion | The natural frequency ( f_n ) is: |
Vibration isolation begins at ( f > \sqrt2 f_n ). For effective isolation below 50 Hz (common for HVAC or large motors), ( f_n ) must be ≤ 5 Hz, requiring very soft pads. However, static deflection limits apply: ( \delta_static = g / (2\pi f_n)^2 ). For ( f_n = 5 ) Hz, ( \delta \approx 10 ) mm – often impractical. Thus, wave pads are typically tuned for 10–30 Hz isolation, offering a compromise between low-frequency performance and stability. Geometric features (pyramids, channels, or periodic bumps) on the pad’s surface convert longitudinal waves into slower shear waves, increasing path length and viscoelastic loss. The loss factor ( \eta ) (ratio of dissipated to stored energy per cycle) for filled elastomers ranges from 0.05 to 0.3. 3. Materials and Manufacturing Common wave pad materials and their properties: For ( f_n = 5 ) Hz, (