If the AC contactor operates for a long time and operates too frequently, its main contact will be burnt, damaged, or loose. Regular maintenance is particularly important. The electromagnetic coil of its AC contactor, which is connected to the power supply for a long time, can also cause heating, deterioration, noise, etc., and needs to be replaced frequently.
The heating cylinder operates for a long time and has a certain application period. But the common fault is a short circuit fault in the power transmission line, which burns out the magnetic connector or heating cylinder terminal. Short circuit faults in the power supply are often caused by human error, such as pulling the machine, leaking glue during injection molding, and loose nodes. Therefore, when disassembling and replacing the heating cylinder, it is necessary to install it firmly, wiring is reliable, and the wiring of the heating cylinder terminal should be tightened first, and then connected to the power plug. After a few hours of operation, the heating cylinder is usually subjected to another torque to prevent node loosening caused by thermal expansion and contraction.
The temperature controller is the key to the heating power circuit. Its accuracy immediately endangers the quality of injection molded products, especially in plastics with accurate temperature regulations, otherwise the rubber material will burn, fade, or be scalded. The temperature control instrument collects the temperature signal of the heating cylinder and compares it with the set temperature signal. Based on the temperature control instrument, it controls whether it is heating up or insulation.
Thermocouples are temperature sensing magnetic components that should be installed reliably, inserted into the temperature measurement hole appropriately, and the thermocouple guide wire connection should be sturdy and reliable. In the general application process, there is a certain deviation in the temperature control meter, which can be used to accurately measure the strength and verify the temperature control accuracy. Common rubber materials can also be applied with a deviation of ± 10 ℃.
The most common malfunction of a temperature controller is ineffective control, and the key is that the relay contacts inside the meter are burnt or calcined, resulting in ineffective temperature control and inaccurate temperature control. The scope of deviation can be caused by faults in the power switch of the dial, or by the impact on the characteristics of the integrated circuit chip inside the thermometer. It can also be caused by faults in internal power circuits such as voltage regulator diodes, resistors, precision resistors, etc. The broken head of the temperature gauge also makes it uncontrollable.
Overhaul the heating power supply circuit, which can be manually inspected from the power supply section to the heating cylinder section. Accurately measure and calibrate the power supply circuit to identify the fault point and electronic components, then disassemble and replace the damaged electronic components, and finally adjust the effectiveness. When disassembling and replacing electronic devices, attention should be paid to the model specifications, shape, specifications, and main parameters, especially when measuring the range of thermocouples, the output power of the heating cylinder, and its serial installation. The nozzle heating cylinder should be minimized from damage caused by adhesive leakage.
