What Is a Centrifugal Separator?

Centrifugal separator is a machine that uses centrifugation to separate components of liquid and solid particles or liquid and liquid mixtures. It is also called a centrifuge.

Industrial centrifugal separators can be divided into

In ancient China, people tied one end of a clay pot with one end of a rope, held the other end of the rope, and rotated the pot to generate centrifugal force to squeeze out the juice of berries in the pot.

Centrifugal separators have a cylinder, called a rotating drum, which rotates at high speed about its axis, which is usually driven by a motor. After the suspension (or emulsion) is added to the drum, it is rapidly driven to rotate at the same speed as the drum, and the components are separated and discharged separately under the action of centrifugal force. Generally, the higher the drum speed, the better the separation effect.

The working principle of centrifugal separator is

Transmission part wear is a common problem in centrifugal separators, and the number is large and the damage is frequent, including

(1) Eliminate the imbalance of empty drums. For a new centrifuge drum, the balance is adjusted by mounting the drum on a balance mandrel. Generally, it must be placed on a dynamic balancer for balance correction. When the drum is mounted on the actual shaft, its balance accuracy will be significantly reduced, because the matching conditions and concentricity between the drum and the balance mandrel and between the drum and the actual shaft are different. About 60% of the vibration of the rotating equipment is caused by the imbalance of the rotor. Doing maneuvering balance on site is the most effective way to eliminate the vibration caused by the imbalance of the empty drum.

(2) Isolate vibration. After adopting the countermeasures to eliminate the imbalance of the air drum, the vibration has been reduced, but the static force during discharging cannot be eliminated by the above method. Taking effective vibration isolation measures can achieve the purpose of reducing the vibration transmitted through the foundation. Vibration isolators are a technical method often used by small and medium-sized rotary separation machinery when installing and damping equipment, and are generally divided into two types: active vibration isolation and passive vibration isolation. According to the theory of vibration isolation, the machine can be regarded as an ideal mass. The vibration isolator is composed of a massless spring and an ideal viscous resistor in parallel. The foundation is absolutely rigid. To produce the vibration isolation effect, only the natural frequency of the excitation frequency is required to be greater than 2 times. Because it is assumed that there is a large distance from the actual situation, the higher the excitation frequency, the larger the difference will be, and it is difficult to obtain a vibration isolation of more than 20db for a single stage vibration isolation. Even with a small damping, the isolation effect can only stay at a certain level. In the range. Therefore, anti-analysis method can be used for vibration isolation research.
(3) Alleviate uneven cloth and sudden increase of excitation force vibration. The random vibration caused by the uneven excitation of the cloth and the sudden increase of the excitation force during discharging can be solved by two measures, such as a dynamic shock absorber and automatic balance. The dynamic shock absorber can transfer the vibration energy to the shock absorber, thereby greatly reducing the vibration of the whole machine and the foundation. However, the dynamic shock absorber cannot fundamentally eliminate the vibration source, and the periodic force on the bearing has not been reduced. Automatic balancing is to set a balancing device on the drum, and it can quickly feedback the vibration signal generated by uneven cloth or sudden force to the control mechanism before generating a damping force equal to or opposite to the unbalanced centrifugal inertial force. In the go, fundamentally eliminate the source of vibration. ^[2]