如何计算Critical Speed

learn.whatIsHeading

Critical speed is the rotational speed at which a rotating shaft reaches natural frequency resonance. Operating above or below critical speed is essential.

公式

Calculate: N_crit = (60 × √(g × δ)) / (π × √(W/g))

W: W value — Variable used in the calculation

分步指南

1Calculate: N_crit = (60 × √(g × δ)) / (π × √(W/g))
2Or use stiffness and inertia: ω_n = √(k/I)
3Operating speed should be <70% or >130% of critical

例题解析

输入

Shaft natural frequency 3000 rpm

结果

Operating range <2100 rpm or >3900 rpm safe

Avoid 2100-3900 band

常见错误注意事项

✕Operating continuously near critical speed
✕Under-estimating critical speed (causes resonance)

常见问题

What happens at critical speed?

Resonance causes excessive vibration, noise, and potential failure from fatigue.

Can you operate near critical speed briefly?

Yes, passing through critical speed quickly during startup/shutdown is acceptable.

准备好计算了吗？尝试免费的 Critical Speed 计算器

自己尝试一下 →