What is a balancing platform?

A balancing platform is a simple structure mounted on springs that supports a rotor for field balancing by allowing free vibration response at operating speed. Its natural frequency is tuned well below the rotor's operating speed.

Why must the platform natural frequency be below operating speed?

The platform natural frequency must be well below operating speed to ensure the system operates in the isolation region, above resonance. At a frequency ratio of 3, transmissibility drops to about 12.5%.

How to choose the number of springs for a balancing platform?

Common configurations: 4 springs for rectangular platforms, 2 for small rotors, 3 for triangular platforms, 6-8 for large heavy rotors. All springs must have equal stiffness.

What materials are best for building a balancing platform?

Welded steel frame or plate (10-20 mm thick) is most common. Aluminum for smaller rotors. Platform mass is typically 10-25% of rotor mass.

Can I use rubber mounts instead of springs?

Yes, but rubber mounts have higher damping and variable stiffness. Coil springs are preferred for their consistent, well-defined stiffness and low damping.

免費工程工具

動平衡平台設計計算器

為現場轉子動平衡設計動平衡平台（軟支撐）。計算所需的彈簧剛性、自然頻率、靜態撓度及傳遞率。

軟支撐設計傳遞率 2–8 個彈簧

轉子質量 (kg)

平台質量 (kg) — 約為轉子的 20%

運轉速度 (RPM)

彈簧數量

頻率比目標值

快速預設

結果

每根彈簧所需剛性

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總剛性 (k_total)

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平台自然頻率 (f_n)

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靜態撓度 (δ_static)

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傳遞率

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頻率比 (f_op / f_n)

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總質量

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平台自然頻率

平台質量-彈簧系統的自然頻率：

其中 m_總 = m_轉子 + m_platform 與 k_總 為所有彈簧的組合剛性 (N/m)。

每根彈簧所需剛性

其中 n 為彈簧數量，而 f_target = RPM/60 × 比率（例如 ×1/3）。

傳遞率

運轉速度下的無阻尼傳遞率：

為獲得良好的動平衡條件，T 應小於 15%。頻率比為 3 時，T ≈ 12.5%。

靜態撓度

實務範例

範例 — 80 kg 轉子於 1800 RPM

已知： m_轉子 = 80 kg, m_platform = 15 kg, 1800 RPM, 4 個彈簧, 比率 1/3

m_總 = 95 kg, f_op = 30 Hz, f_target = 10 Hz

k_總 = 95 × (2π×10)² = 375,055 N/m = 375.1 N/mm

k_每根彈簧 = 375.1 / 4 = 93.8 N/mm

δ_靜態 = 95×9.81 / 375,055 × 1000 = 2.49 mm

T = 1/(3²−1) = 12.5%

⚠️ 注意： 確保所有彈簧剛性相等且負荷居中。撓度不均會導致傾斜，進而扭曲動平衡校正過程中的振動讀數。