13509649021
More than ten years Hot runner product development experience
13509649021
More than ten years Hot runner product development experience
Date：2020-07-02View：9947
Discussion on the application of hot runner temperature control box in the system
1, the temperature control box is the temperature control of the hot runner, so as to better make the hot runner produce benefits.
2. The control principle of the temperature control box can be divided into two types: one is controlled by the temperature change of the object to be cooled, the other is controlled by the temperature change of the object to be cooled, and the other is controlled by the temperature. Controlled by an electronic temperature controller.
3. The temperature controller is divided into mechanical pressure, electronic pressure and vapor pressure.
Mechanical: steam pressure thermostat, liquid expansion thermostat, gas adsorption thermostat, metal expansion thermostat.
The vapor pressure types are divided into gas - fill type, liquid - gas mixture type and liquid - fill type.
Electronic temperature controller (resistance type) is measured by resistance temperature sensing method. Typically, platinum, copper, tungsten, and semiconductor (thermistors, etc.) are used as temperature measuring resistors. Each of these resistors has its own sweet spot.
4. An effective temperature control cabinet can quickly and safely raise the temperature of the entire system to a predetermined point.
There are three ways to do this:
(1) Drive power - this allows the entire system to be heated to a predetermined temperature without having to worry about compensating the larger cold diverter. Smaller injectors will be heated to extend the service life of the heater. The power drive keeps each area under surveillance, slowing the rise of the fast heating zone until the others catch up. This method enables a system composed of different thermal masses to be heated to a predetermined temperature as quickly as possible without extending the heating time of smaller elements.
(2) Wideband control: The controller has a set of parameters and is flexible enough to effectively control the temperature of different mass bodies (i.e., larger diverters and smaller ejectors) without operator input of other parameters. The operator does not have to measure the area accurately according to the quality, thus saving time and reducing the chance of errors.
(3) Temperature-controlled oven baking - as the heater absorbs moisture, short circuit is likely to occur during the start-up process. The voltage and power of the wet heater can be adjusted to disperse water as soon as possible without short-circuiting the heater. If the heater is dry, the controller also knows to electrify the system as soon as possible. However, if there is moisture, the control system will use a step-down power supply for safe, rapid drying, and then gradually revert to the original power at an appropriate rate based on the humidity at the time.
There are two ways to start the heater: voltage scale and time scale. Although the voltage-type and time-type transmit the same power to the heater proportionally, they transmit power in different ways, which will affect the service life of the heater. The time-type ratio transmits power through the pulse mode, shaking the heater at 100% power each time, resulting in increased temperature deviation within the heater element. This will cause the heater elements to age rapidly. On the other hand, the voltage ratio USES smaller energy pulses more frequently, which reduces the heater element's contact with extreme temperatures, reduces thermal shock and thermal fatigue, and thus prolongs the service life of the heater.
