How to debug the hot runner system after installation?

The debugging after the installation of the hot runner system is a key step to ensure its normal operation. The following is a detailed debugging process:

1、 Check before startup

Before debugging, it is necessary to conduct a comprehensive inspection of the entire system. Confirm whether all connection parts, such as the connection between the hot runner plate and the splitter plate, and the connection between the nozzle and the mold cavity, are firm to prevent plastic leakage. At the same time, check whether the wiring connection between the heating element and the temperature sensing element is correct, which is the basis for ensuring accurate temperature control. In addition, it is necessary to check whether the cooling system around the hot runner system is working properly, as cooling is crucial for maintaining the overall temperature balance of the mold.

2、 Temperature adjustment

Initial warming up

Turn on the heating device and slowly raise the temperature of the hot runner system to the set temperature. This heating process should be gradual to avoid excessive thermal stress caused by rapid heating, which can damage the hot runner system. Generally speaking, it is more appropriate to control the heating rate at 1-2 ℃/min.

At the same time, closely monitor the data feedback from the temperature sensor to ensure that the temperature in each heating area can rise uniformly and remain stable after reaching the set temperature.

Temperature balance adjustment

Due to varying heat losses in different parts of the hot runner system, uneven temperature may occur. Balance the temperature by adjusting the heating power or optimizing the insulation measures of the hot runner system. For example, if the temperature of a nozzle is always lower than other parts, the heating power of that area can be appropriately increased until the temperature deviation of each nozzle and flow channel is controlled within the allowable range, usually less than ± 5 ℃.

3、 Injection molding debugging

Trial injection molding

After stable temperature adjustment, proceed with trial injection molding. Select appropriate plastic raw materials and set the injection parameters of the injection molding machine to lower values, such as lower injection pressure, injection speed, and shorter holding time. This is to preliminarily observe the flow of plastic in the hot runner system, in order to avoid overflow or other molding defects caused by excessively high parameters.

Observe the flow of plastic from the nozzle to determine if it is smooth. If there is poor flow or blockage of plastic, it is necessary to check whether there is any blockage in the nozzle or whether the temperature is too low, which may cause the plastic to solidify.

parameter optimization 

Based on the results of the trial injection molding, gradually adjust the injection molding parameters. Increase injection pressure and speed, extend holding time, etc., until satisfactory injection molded products are obtained. During this process, attention should be paid to observing the appearance quality of the product, such as whether there are defects such as burrs, shrinkage, and weld marks. If these problems occur, it is necessary to adjust the parameters or inspect the relevant components of the hot runner system in a targeted manner.

By following the detailed debugging steps above, the hot runner system can be optimized to ensure the quality and efficiency of injection molding.