At present, the common mixer upstream system in China mainly has two types of structures:stereoscopic and negative pressure mixer upstream systems. The stereoscopic upstream system is widely used in China for various mixer models and all rubber products. The negative pressure mixer upstream system is used only for recent years and it mainly works with small mixers and kneaders. The composition of the two structures of mixer upstream systems are as below:

I. Composition of Stereoscopic Mixer Upstream System

1. Carbon black pneumatic conveying;

2. Carbon black (fillers) storage, automatic weighing and feeding;

3. Oil storage, automatic weighing and feeding;

4. Polymer weighing and automatic feeding;

5. Mixer dust collection;

6. Control system.

II. Composition of Negative Pressure Mixer Upstream System

1. Carbon black (fillers) unpacking and conveying;

2. Carbon black (fillers) conveying pipe;

3. Carbon black (fillers) weighing unit and feeding;

4. Oil, polymer, dust collection and control system, the same as the stereoscopic upstream system.