About Soft bearing balancing Machine and Hard bearing balancing Machine

Hard Bearing Balancing Machines

1. Design Features

Hard bearing balancing machines fall into the pre-resonance category. These machines boast extremely rigid supports, which have resonant frequencies significantly higher than the maximum rotor speeds. This design ensures operation outside the resonance zone, enhancing precision.

The supports, typically robust plates with strategically placed slots or cuts, introduce areas of controlled flexibility. This feature allows for subtle deformations under the forces exerted by an imbalanced rotor, essential for accurate balancing.

2. Operating Principle

The procedure for using a hard bearing balancing machine involves several key steps:

• Rotor Installation: Securely mount the rotor on the hard bearings.
• Spin-Up: Accelerate the rotor to the required rotational speed.
• Force Transmission: The rotor’s imbalance forces transmit through the bearings to the machine’s supports.
• Minute Deformation: The outer parts of the supports undergo cyclical deformations relative to their static inner areas, typically very minimal.

To measure these minute deformations, the machines utilize:

• Force sensors (piezoelectric): These measure the force exerted on the supports.
• Non-contact displacement vibration sensors: These track the minuscule movements within the support structures for utmost precision.

The machine’s advanced measurement and computation system processes these sensor signals, accurately identifying the imbalance’s magnitude and angular position, and calculating the appropriate correction weights.

3. Advantages of Hard Bearing Machines

Hard bearing machines excel in versatility, capable of precisely balancing rotors of various sizes and weights. They perform high-accuracy balancing at low speeds, often between 200-500 RPM, which can mirror the rotor’s operational conditions, thus ensuring superior accuracy.

4. Disadvantages of Hard Bearing Machines

The sophistication required for rigid supports and precision sensors makes these machines more complex than their resonance-based counterparts, leading to higher costs.

5. When to Choose Hard Bearing Machines

Opt for a hard bearing machine when balancing a diverse array of rotors, requiring the highest accuracy, or when low-speed balancing aligns with the rotor’s operational speeds.

Soft Bearing Balancing Machines

Design and Principle of Operation

Soft bearing balancing machines are categorized as resonance-type due to their flexible supports, designed with resonant frequencies much lower than the rotor speeds. This design allows the supports to vibrate in response to imbalance forces, with strategically placed vibration sensors capturing the amplitude and phase of these vibrations.

The machine’s system analyzes this data to pinpoint the imbalance and strategize the necessary corrections.

Advantages and Disadvantages of Soft Bearing Machines

While simpler and more cost-effective, soft bearing machines are particularly sensitive to imbalances, making them suitable for lighter rotors. However, they are not ideal for very heavy rotors or for operating at or near critical speeds.

Expanding Your Knowledge

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