Decanter Centrifuge Differential, Centrifuge Drive

Centrifuge Differential Overview

The decanter centrifuge differential is an important part of the decanter centrifuge transmission system. Its main function is to realize the differential movement between the drum and the screw to achieve the effect of solid-liquid separation.

 

The Role Of The Differential

 

The main function of the differential is to make the spiral and the drum produce a constant differential speed, which is the key to achieve solid-liquid separation

In the horizontal screw centrifuge, the drum and the spiral rotate at a certain differential speed in the same direction at high speed. The material is continuously introduced into the inner cylinder of the feeding spiral from the feed pipe and enters the drum after acceleration. Under the action of the centrifugal field, the heavier solid phase is deposited on the drum wall to form a sediment layer, while the clarified liquid forms an inner liquid ring. The spiral pusher rotates at a speed slightly lower than that of the drum, continuously pushing the solid phase sediment deposited on the drum wall to the slag discharge port, while the clarified liquid flows out from the liquid phase end, thereby achieving solid-liquid separation.

 

Differential Types

 

Cycloidal differential:

• Compact structure and easy installation.
• However, the output torque is small, and it has limitations if it is applied in areas that require large thrust (such as steel waste slag, coal mine sewage, etc.).

Planetary differential:

• Relatively large structure, torque output is competitive.
• However, when applied to centrifuges, the installation size is limited and the performance of the whole machine may be compromised.

Hydraulic differential:

• It is a variable displacement radial piston motor that generates differential speed through a hydraulic system.
• It can achieve stepless speed change in a wide range, greatly improving the application range of the centrifuge.
• The hydraulic differential can output even more torque than the planetary differential in the same application range, but the imported hydraulic differential is expensive, which increases the manufacturing cost of the decanter centrifuge.

 

Causes And Solutions For Differential Damage

 

Cause of damage:

• Poor lubrication: Insufficient lubricating oil, unqualified oil quality or oil circuit blockage will cause increased wear of components such as differential gear pairs and bearings.
• Overload operation: Material concentration is too high, viscosity is too high or contains a lot of impurities, which will cause the drum and screw to overload, thus accelerating the damage of the differential.
• Improper operation: Quick starting, emergency stopping or frequent adjustment of differential ratio may cause impact and damage to the differential.
• Insufficient maintenance: Failure to replace severely worn gear pairs and bearings in a timely manner will lead to reduced performance or even damage to the differential.

Solution:

• Check the lubrication system regularly to ensure that there is sufficient lubricating oil and the oil quality is qualified.
• Control material concentration and viscosity to avoid overload operation.
• Start, stop, adjust and other operations strictly in accordance with the operating procedures.
• Regularly perform maintenance and service on the differential and replace severely worn parts in a timely manner.

 

How The Differential Works

 

The working principle of the differential is mainly to use the kinetic energy generated by the high-speed rotation of the motor to work. In the horizontal screw centrifuge, the motor transmits power to the differential through the input shaft, and the differential distributes the power to the bowl and the screw through the gear pair, so that the two rotate in different directions at the same speed, thus producing a differential effect. This differential motion enables the screw pusher to continuously and stably push the solid phase sediment deposited on the wall of the bowl to the slag discharge port, while the clarified liquid flows out from the liquid end.