The design and selection of stirring device are closely integrated with the purpose of stirring operation. Different mixing processes need to be realized by different mixing devices. In the design and selection, we should first determine the mixer type, motor power and mixing speed according to the purpose and requirements of the mixing operation, and then select the reducer, frame, mixing shaft, shaft seal and other components. Total specific steps and methods are as follows.

1. In accordance with the process conditions, mixing purposes and requirements, select the agitator type. When selecting the agitator type, fully grasp the power characteristics of the agitator and the causal relationship between the flow state generated by the agitator in the mixing process and various mixing purposes.

2. In accordance with the determined agitator type and the flow state generated by the agitator in the mixing process, the process control requirements on mixing and blending time, settling speed and dispersion, determine the motor power, mixing speed and agitator diameter through experimental means and computer simulation design.

3. In accordance with the motor power, stirring speed and process conditions, select and determine the reducer model from the reducer selection table. If the reducer is selected according to the actual working torque, the actual working torque should be less than the allowable torque of the reducer.

4. Select the frame and coupling of the same type and specification as d according to the output shaft head d of the reducer and the support method of the mixing shaft system.

5. Select the shaft seal type according to the size of the agitating head do of the frame, installation space, working pressure and working temperature.

6. According to the installation form and structural requirements, design and select the structure type of mixing shaft, and check its strength and rigidity.

If the design is based on rigid shaft, n/nk≤0.7 under the condition of meeting strength.

If the design is based on flexible shaft, n/nk>=1.3 under the condition of meeting the strength.

7. According to the nominal heart DN of the frame, the type of shaft and pressure level of the mixing shaft, choose the installation bottom cover, flange base or flange

8. According to the support and vibration resistance conditions, determine whether to configure auxiliary support.