Home > News > Content
The Problem That The Mold Temperature Machine Should Pay Attention To When Controlling The Temperature Of The Injection Mold
Dec 08, 2018

Core Tips: 1. The configuration of the Suzhou mold temperature machine and the configuration of the mold temperature machine should be comprehensively determined according to the processed materials, the weight of the mold, the required warm-up time and the productivity kg/h. When using heat transfer oil, operate

         1. The configuration of the Suzhou mold temperature machine and the configuration of the mold temperature machine should be comprehensively determined according to the processed materials, the weight of the mold, the required warm-up time and the productivity kg/h. When using heat transfer oil, the operator must comply with such safety regulations: Do not place the mold temperature machine close to the heat source furnace; the joint uses a taper leak proof and a hose or tube with temperature and pressure resistance; periodic inspection Temperature control circuit mold temperature machine, joints and molds have leaks, function is normal; regular replacement of heat transfer oil; synthetic oil should be used, good thermal stability, small tendency to coking. In the use of the mold temperature machine, it is extremely important to select a suitable heat transfer fluid. Water is used as a heat transfer fluid. It is economical, clean and easy to use. Once the temperature control circuit leaks like a hose coupling, the water flowing out can be directly discharged to the sewer. However, water as a heat transfer fluid also has disadvantages: water has a low boiling point; depending on the composition of the water, corrosion and scaling may occur, causing an increase in pressure loss and a decrease in heat exchange efficiency between the mold and the fluid, and the like. When using water as a heat transfer fluid, the following precautions should be considered: pre-treatment of the temperature control circuit with an anti-corrosion agent; use of a filter before the water inlet; regular cleaning of the water temperature machine and mold with a descaling agent. There is no disadvantage of using water when using heat transfer oil. The boiling point of oil is high, they can be used for temperatures higher than 300 ° C or higher, but the heat transfer coefficient of heat transfer oil is only 1/3 of water, so the oil temperature machine has no extensive use of water temperature in injection molding.

 

   2. The type of Shanghai mold temperature machine is divided according to the heat transfer fluid (water or heat transfer oil) used. The water-use mold temperature machine usually has a maximum outlet temperature of 95 °C. Use oil-operated mold temperature machine for working temperature ≥150 °C. Usually, the mold temperature machine with open water tank heating is suitable for water temperature or oil temperature machine, and the maximum outlet temperature is 90 ° C to 150 ° C. The main feature of this mold temperature machine is simple design and economical price. On the basis of this machine, a high-temperature water temperature machine is used, which allows an outlet temperature of 160 ° C or higher. Since the temperature is higher than 90 ° C, the thermal conductivity of water is higher than that of the same temperature. A lot better, so this machine has outstanding high temperature working ability. In addition to the second, there is a forced flow mold temperature machine. For safety reasons, this mold temperature machine is designed to operate at a temperature above 150 ° C, using heat transfer oil. In order to prevent overheating of the oil in the mold warmer heater, the machine uses a forced flow pumping system, and the heater consists of a number of tubes stacked with finned heating elements for diversion.

   3. Pre-conditions for effective control of mold temperature The temperature control system consists of three parts: mold, injection mold temperature machine and heat transfer fluid. In order to ensure that heat can be added to the mold or removed, the various parts of the system must meet the following conditions: First, inside the mold, the surface area of the cooling passage must be large enough, and the diameter of the flow path should match the pump capacity (pump pressure). The temperature distribution in the cavity has a large influence on the deformation and internal pressure of the part. Properly setting the cooling channel reduces the internal pressure and improves the quality of the molded part. It also reduces cycle times and reduces product costs. Secondly, the mold temperature machine must be able to keep the temperature of the heat transfer fluid constant within the range of 1 ° C - 3 ° C, depending on the quality requirements of the injection molded parts. The third is that the heat transfer fluid must have good heat transfer capacity, and most importantly, it must be able to introduce or export a large amount of heat in a short time. From a thermodynamic point of view, water is significantly better than oil.

   4. The injection mold temperature machine is composed of a water tank, a heating and cooling system, a power transmission system, a liquid level control system, a temperature sensor, an injection port and the like. Typically, the pump in the power transmission system causes the hot fluid to reach the mold from the tank with the built-in heater and cooler, and then from the mold back to the tank; the temperature sensor measures the temperature of the hot fluid and transmits the data to the control section. Controller; the controller adjusts the temperature of the hot fluid to indirectly adjust the temperature of the mold. If the mold temperature is in production and the temperature of the mold exceeds the set value of the controller, the controller opens the solenoid valve to open the inlet pipe until the temperature of the hot liquid, that is, the temperature of the mold returns to the set value. If the mold temperature is lower than the set value, the controller of the mold temperature machine turns on the heater.