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The needle valve type hot runner saves materials, the surface of the plastic parts is beautiful, and the internal quality is tight and the strength is high. Second, the working principle of the temperature controller: Another component of the hot runner technology is the heating and temperature control system, the advantages and disadvantages of the heating and temperature control system, directly affecting whether the mold can work continuously, it can be said that the heating and temperature control system is

The entire hot runner occupies a very important position.. In the heat preservation phase, the working temperature is constant, there is no large fluctuation, and the heating element is always in plastic injection mould a low voltage constant working state, and has no impact on the heating element. The temperature measurement system is updated to make the temperature control system applicable to various thermocouples with an indexing degree, the measurement accuracy is improved to 1%, and the over-temperature alarm is improved. The working principle is as follows: When the system is first turned on, the system automatically enters the soft start state, and the voltage of the heating element gradually rises from zero to the rated voltage. The thyristor zero-trigger device not only ensures the conduction in the zero phase, but also does not damage the power grid, and further improves the service life of the heating element. The soft start function not only can reduce the impact of the heating element when it is heated in the cold state, but also can drive out the moisture generated when the mold is not used for a long time.About hot runner temperature controller

The thermostat functions to control the temperature in the hot runner system. The heating and temperature control system of the hot runner basically consists of a heating device, a monitoring point and a control system. The cylinder type * hot runner temperature controller and timing controller control the cylinder to push the needle valve to close, the structure is more complicated, but the design itself is simple. The role. Fluctuations within the scope. The design of the adiabatic runner is complex, but the effect and maintenance costs are very low and do not delay working hours. The ideal control system can not only effectively control the temperature change in the flow channel, but also prolong the service life of the heating device, so as to achieve continuous and long-lasting work of the mold. In the output control mode, the internationally new pulse width adjustment technology and zero-trigger and soft-start mode are adopted. The heating device is generally a heating rod and a heating coil; the monitoring point is a probe disposed near the weak portion or the working surface in the entire hot runner; the control system is used to regulate the temperature of the entire hot runner system to ensure that the temperature is at a certain setting. And falling, when the temperature rises to the set value, the voltage of the heating element is a constant low pressure state, just to supplement the heat loss of the hot runner system. Next, let's briefly introduce the hot runner flow temperature controller. It is necessary to design the voltage of the heating element in the heat preservation stage to be 50% to 60% of the rated voltage, by increasing the broken wire alarm of the heating element. First, the hot runner temperature controller classification: adiabatic flow channel, cold runner, hot runner. When the temperature approaches the set value, the working voltage on the heating element will stabilize with the temperature. The temperature control system selects different heating powers, which has a great influence on the service life of the heating elements. The output control device selects high-power two-way thyristor output, which is stable in operation and reliable in performance. There are two major types of needle valve hot runners in the world (according to the injection principle): cylinder type and spring type. Generally, it is set for 8 to 20 minutes, which also plays a role in protecting the hot runner system of the mold. The open structure is simple, the material has high limitation, the drawing and leakage are easy to occur, the surface quality is poor, and the application is less in the high-precision molds in foreign countries, and the same auxiliary mold can be mixed with the needle valve type of different manufacturers. When designing the control system, it should be considered from the aspects of stability, reliability and durability. The temperature of the nozzle and the heater of the manifold in the system is controlled by the thermocouple to keep the plastic molten; and the temperature control is optimized according to the different characteristics of different plastics