In rotational systems, peripheral velocity (also known as tangential or linear velocity at the rim of a rotating body) plays a key role in determining the power transmitted. Mathematically: P=F⋅v

Where:

• P = Power
• F = Force (typically tangential)
• v = Peripheral velocity

Since force is related to torque (T=F⋅r), we also get: P=T⋅ω=F⋅r⋅ω=F⋅v

Thus, increasing peripheral velocity enables higher power transmission, provided that the force remains constant. This is why higher-speed drives can theoretically transmit more power, but only up to a limit.

🌀 Centrifugal Force: The Speed Barrier

As speed increases, rotating components experience centrifugal force: F_c = m⋅r⋅ω²

Where:

• Fc​ = Centrifugal force
• m = Mass of the rotating object
• r = Radius
• ω = Angular velocity

In belt drives, this force acts outwardly on the belt, increasing the overall tension in the system. However, it does not contribute to useful power transmission—instead, it:

• Increases bearing load
• Reduces effective tight-side tension
• Decreases power transmission efficiency
• Can cause belt slippage or failure at very high speeds

🏗️ Increased Belt Load & Reduced Tension

The combined effect of centrifugal force and high-speed operation leads to a paradox:

• The total belt tension increases due to centrifugal effects
• But the useful (tight-side minus slack-side) tension decreases

This results in diminished drive capacity. For flat belts, this phenomenon is more pronounced, hence why their safe peripheral velocity is limited to around 25 m/s (standard) or 50 m/s (high-performance materials).

🔗 Limiting Factors for Chain Drives

Chain drives, unlike belts, offer positive engagement between the driving and driven sprockets. However, at high speeds they are limited by:

1. Centrifugal Force on Links
   • Causes increased tension in the chain spans
   • Induces fatigue and stretch over time
2. Impact Loading (Knocking)
   • When links mesh with sprocket teeth, especially at higher speeds, they experience shock loads due to:
     • Poor alignment
     • Chain wear
     • Slack in the system
3. Vibration and Noise
   • Chain drives become significantly louder at high speeds

As a result, the recommended peripheral velocity is limited to about 25–30 m/s, beyond which operational issues outweigh benefits.

⚙️ Precision in Gear Teeth Cutting at High Speed

In gear drives, power is transmitted through meshing teeth, which require very high precision, especially at high speeds. The problems with poorly manufactured gear teeth at high speed include:

• Increased dynamic loading
  • Inaccuracies cause misalignment and interference, leading to fluctuating loads
• Gear tooth wear and breakage
• Noise and vibration
  • These are amplified with speed, reducing system life

To mitigate these issues:

• Use high-precision manufacturing (e.g., hobbing, grinding)
• Employ profile correction (tip relief)
• Ensure balanced shafts and minimal backlash