First of all, we will analyze the cooling principle and method of the lower mold temperature machine. Different circulating heat transfer media can be divided into two types: water type mold temperature machine and oil type mold temperature machine. Generally, water type mold temperature machine adopts direct cooling, while oil type mold temperature machine adopts indirect cooling.

Direct cooling is a way used in water-type mold temperature machine equipment. There is no independent heat exchange unit inside the unit. When the cooling function is turned on, the cooling solenoid valve will open to allow cooling water to be directly injected into the pipeline system and discharge a part of Hot water to achieve the purpose of rapid cooling. The advantages of adopting direct cooling method are rapid cooling and relatively low unit cost. Since cooling water directly enters the pipeline, the system temperature can be rapidly reduced to meet the demand of rapid cooling. Its disadvantages are small application range, large impact on cooling capacity, and poor temperature control accuracy. In addition, if the water quality of cooling water source is not treated, it is easy to scale in the pipeline of the system, affecting the heat transfer efficiency in the later period.

Another cooling method is indirect cooling. A plate heat exchanger or an oil cooler is installed inside the mold temperature machine. The heat medium and the cooling water source in the system exchange heat in the heat exchanger, thereby reducing the medium temperature. The advantages of indirect cooling are high temperature control accuracy and strong adaptability, which can be applied to the temperature control of high-temperature oil circulation temperature control machine. Moreover, because the heat transfer medium is cooled first, the cooling impact on the temperature control equipment is relatively small. Of course, its disadvantage is that the cooling speed is relatively slow, and the price is more expensive than the direct cooling method.

If the temperature of the water-type mold temperature machine does not drop, we generally conduct investigation and maintenance from the following aspects:

1. The cooling solenoid valve is damaged

It is necessary to check whether the solenoid valve coil can work normally, and replace it if it is damaged;

2. The panel does not output cooling signal

Check the circuit carefully or use the part replacement method

3. Circuit fault path

The circuit part of the system needs to be checked.

4. The cooling water inlet or outlet pipeline is blocked

Check whether the valve in the cooling water pipeline is fully open, and ensure that the flow and pressure of the cooling water are sufficient

5. The heating contactor is stuck and has been heating

Observe the pull-in state of the contactor and damage the electrical components

6. If the temperature of the oil-type mold temperature controller cannot drop, we need to check whether the cooling plate is changed or the cooling exchanger is blocked in addition to investigating the above several possible causes of failure.