Precautions for application of hot runner system in Guangdong plastic mould factory

In the design and manufacture of plastic molds, some molds need to use hot runner system. What should be paid attention to when using runner?

Precautions for application of hot runner system in Guangdong plastic mould factory

1. The channel is heated externally and consider removing hot spots from the design (for example, four heaters are placed symmetrically around the flow channel).

2. In order to heat the manifold correctly, use at least 50 watts / cubic inch of steel, and the heaters are evenly distributed on the manifold.

3. Manifold passage shall be at least 0.50 inch (12.7 mm). Large parts and long flow lengths require larger diameters.

4. Each channel shall be designed as streamline without dead corner of material suspension and decomposition. There is a male plug at the corner.

5. In order to maintain temperature consistency, it is recommended to use voltage proportional temperature control.

6. The spout shall be short and straight, more than 6 inches long, and two temperature control areas shall be set.

7. Manifold split joint and blanking nozzle shall be properly insulated from clamping steel plate. There is an air gap of 0.03 inch (0.79 mm) between the two to reduce the metal surface connection, and the gasket is supported with stainless steel or titanium.

8. The injection tube has an external heater that reaches or exceeds the die hole at least.

9. Each injection port has a separate sealing ring controller.

10. The resin melt temperature of manifold and blanking tube is the same as that of tube.

11. Thermal insulation material runner system is not applicable to engineering thermoplastic.

12. For ULTEM resin, the inherent mold area will produce stripes during fabrication, so it is necessary to know what special valve gate hot runner system needs to be used.

Mold temperature control of Guangdong plastic mold factory

In the production process of plastic mold factory, it is very important to properly control the surface temperature of core and cavity. Now let's look at how I controls the temperature of the plastic mold.

In order to independently control half the temperature of the die, a dual zone or a separate controller is usually required. In order to prolong the cycle time and effectively control the component tolerance, unified die temperature control is very important. For large hollow or core, it is generally recommended to keep the temperature difference of steel below 20f (- 7C) and small parts below 5F (- 15C). The more strict the control, the greater the degree of freedom of machining. Cooling channels above 12.7 mm (1 / 2 inch), 38 ~ 50.8 mm (1-1 / 2 inch ~ 2 inch), 1 / 2 inch higher than hollow and core surfaces. The correct temperature adjustment makes the die surface heat evenly. The huge temperature difference on the mold surface leads to different cooling rates, resulting in the injection stress of the product. For the same reason, the temperature difference between the core and cavity usually does not exceed 40F (22c).