Effectively reducing failures and maintainence time of unit hot runner

   Compared with ordinary hot runners, the unit and integrated hot runner system is more convenient for injection and maintenance or replacement of parts, thus effectively reducing production time and increasing production efficiency.

   Hot runner system has been widely used in injection molding. Because hot runner technology can accelerate the speed of injection molding production, and also improve the quality of products, resulting in greater economic benefits. Nowadays, advanced injection molding technology, such as insert molding, multilayer injection molding and multi-material injection molding, can not be lack of hot runner technology. Large parts, such as automobile bumpers, are restricted by the distance between the molten material and the wall thickness of the parts, as well as the limitation of the weld line. In the production process, hot runner system must be used. Hot runner technology is playing an increasingly important role in the field of injection molding.

   Although the hot runner is part of the injection mold, its task and function are completely different from the mold itself. The hot runner itself is a complete and independent system unit. It requires high precision installation, connection and operation. For this reason, more and more modern advanced hot runner systems are being provided to customers in the form of hot half-die after full installation and commissioning. This method can prevent users from making mistakes in system installation, simplifying system connection and reducing the time to install the system on the die.

1. Advantages of unit hot runner system

   On the unit system, the nozzle and runner plate form a complete and independent "embedded" monolithic unit. The runner on the runner plate is directly and tightly matched with the nozzle, so there will not be a bad flow path between the runner connections. The traditional "casting sleeve" hot runner system is prone to leak between the nozzle and runner plate during thermal expansion. In case of leakage, it is necessary to stop production, clean up and repair and affect production.

   At the center of the injection mold, there are few parts in contact with the template, and the hot runner system parts at the limited contact point are made of bad heat conduction material and do not need the template to clamp the prestress of the hot runner system. Because the contact area between the system and the template is very small, the temperature control of the system is very precise and stable, and the energy consumption is much lower than that of the traditional hot runner system.

   Due to the systematic design of the unit, the hydraulic pipes can be directly installed directly on the hot runner shunting plate. The valve gate in the hydraulic cylinder drive device can also be directly installed on the system, so that the mold does not need another valve controller when working on the injection unit system, making the mold more flexible and convenient. The electrical and hydraulic connection modes in the system can be designed and manufactured according to the special requirements of users.

2. The design of the traditional hot half-die

    The traditional hot half-die is developed on the basis of the hot runner system. Its nozzle is not fixed on the channel plate, but is suspended and attached to the channel plate. This system requires a fixed plate to compress the nozzle and the runner plate together.  

    The average temperature difference between hot runner systems and dies used in most plastics is about 200 ℃, and because of the contact between them, the loss of temperature and energy will be increased, and the flow dead angle of melt flow may occur at the same time at the connection between the channel plate and the nozzle.
    When the hot runner needs maintenance, the traditional hot mold must be completely disassembled. Because the nozzle is not connected to the channel board, the electrical and hydraulic connections must be completely or partially disassembled, and all the components will have to be connected to the original sample when the maintenance is finished. This will take more time than the unit system, and it may duplicate some installation errors.

3. Integrated hot runner system

   The unit system greatly improves the quality and highlights the superiority of maintenance and economy. An integrated hot runner system, which is further developed based on the design of the unit system, embeds all the wires from the heater to the junction box in a specially designed conduit, thus avoiding the phenomenon that the heating lines or thermocouple lines that may occur during the assembly process are jammed or pressed.

The integrated system can also provide users with more benefits. For example:

(1) integrated system can not be removed from the injection molding machine in routine maintenance.

     Although some of the maintenance of the traditional hot half-die can be carried out directly on the injection molding machine, it is only limited to the front end of the nozzle because of the existence of the fixed plate of the nozzle. If you want to repair other parts, you need to expose the system completely, so the hot runner system must be completely discharged from the injection molding machine.