What is the Common rotor imbalance problem in laboratory centrifuges?

- Dec 12, 2018-

Generally, the centrifuges equipped in the laboratory are divided into two types: high-speed centrifuges and low-speed centrifuges. As the core working part of the centrifuge, the rotor body often encounters the problem of rotational imbalance. The following is followed by the Xiangzhi centrifuge to understand the cause of centrifugation. Common factors for unbalanced operation.

The first is a high-speed centrifuge. The high-speed centrifuge uses a variable frequency motor with a speed higher than 10,000 rpm. The second is a low-speed centrifuge that uses a brushless motor. The maintenance speed is generally less than 10,000 rpm. The premise that a centrifuge can normally operate at a high speed is that the rotor body must be balanced and rotated in the centrifugal chamber. The reasons for the unbalanced rotation of the rotor body are as follows:

1. The working sample is not weighed as required. (In principle, the weight difference of each sample should be less than 1 gram.) The weight difference is beyond the allowable range of the machine. This will cause the center of gravity of the rotor body to be displaced, deviating from the central axis and causing unbalanced vibration. .

2. The sample to be centrifuged is not symmetrically placed in the center, causing severe vibration, causing the drive shaft to be skewed, causing irreversible balance damage. In this case, the manufacturer should be contacted to replace the corresponding parts after sale.

3. The residual sample in the centrifugal cavity of the high-speed centrifuge rotor body, or the separation of corrosive substances, causes chemical corrosion of the rotor body and changes the chemical structure and weight of the material of the rotor body. This weight difference is often neglected, but it is ubiquitous, so operators need to develop good habits, strictly follow the instructions for use, do not violate the rules, clean up the stains after use, keep the centrifuge cavity clean and dry, avoid The machine is subject to corrosion damage.

4. The centrifuge is not placed horizontally or displaced during operation to cause the support feet to be unbalanced. At this point, stop the machine from the new position to the horizontal position before using it.