The hottest frequency converter helps plastic mach

Frequency converter helps plastic machinery save energy

due to the wide application of plastic products in industrial and agricultural production, plastic machinery has become an important industry in the machinery industry where Xinda signed a contract of 2.5 billion and invested 300000 tons in the manufacturing of biological composites and additives. After the application of frequency conversion and speed regulation technology, plastic machinery can save electric energy (about% can be saved) and reduce the impact on electricity, so as to achieve green use. The high-energy ion beam 3D intelligent spray welding equipment and cermet products of Zhongwu Hongyu, a subsidiary of the electric control company, have been implemented and utilized in batches, and can also improve product quality and output wear resistance

there are many kinds of plastic machinery, including plastic calender, plastic film blowing machine, plastic film bag sealing and cutting machine, injection molding machine, plastic trunking machine, plastic gusset machine, plastic pipe extruder, film extruder, molding machine, plastic coating compound machine, wire drawing machine, kneading machine, plastic granulator, auxiliary machinery (blower, liquid feeding, mixing, mixing), etc. Among the above-mentioned plastic machines, except for the four roll calender, which requires high synchronization accuracy, the rest are very common production machines. The requirements for the drag system are basically the same

1. The speed can be adjusted smoothly within a certain range to facilitate the production of different varieties of products

2. Start and brake smoothly. Plastic machinery is generally a constant torque load. When starting at low speed, there must be a certain torque to make the machinery start smoothly

3. Stable performance and reliable operation. In order to ensure the quality of plastic products, the work of the drag system must be very stable

take the variable frequency control system of the film blowing machine as an example to make a brief introduction:

the variable frequency speed regulation drive system of the film blowing machine includes two parts: one is the variable frequency governor of the extrusion main motor, and the other is the variable frequency governor of the traction motor. Their control is very simple. The speed of the motor can be adjusted through the keyboard on the panel or an external given potentiometer. The function preset of the frequency converter is mainly in the following aspects:

1. Frequency setting: it can be given by keyboard or external potentiometer

2. Upper and lower limit frequencies: the upper limit frequency should generally be slightly higher than the rated frequency, and the lower limit frequency is usually set to 3Hz

3. Inching frequency: generally, it can be preset to 8Hz

4. Acceleration and deceleration time: since plastic machinery does not need to be started and braked frequently, there is no strict requirement for acceleration and deceleration. The basic principle is not to exceed the rated current, but for the sealing and cutting machine, it should be preset as short as possible

5. Torque compensation: since plastic machinery has low requirements for hardness and dynamic response of mechanical characteristics, v/f control mode can be adopted

6. Presetting of DC braking function: general plastic machinery does not need to preset DC to integrate into local cooperation and win-win; Control the braking function of refining capacity, but for the sealing and cutting machine, in order to reduce the deceleration time, it is appropriate to preset DC braking