When using mold heating tubes, mold design needs to consider multiple special requirements to ensure that the heating tubes can work effectively and safely, while ensuring the overall performance of the mold.
1、 Design of installation holes for heating tubes
Firstly, the dimensional accuracy of the installation holes for the heating tube. The outer diameter of the heating tube needs to be closely matched with the installation hole. Generally speaking, the diameter of the installation hole should be slightly larger than the outer diameter of the heating tube by 0.1-0.3mm. This can ensure the smooth installation of the heating tube and reduce heat loss. For example, for a heating tube with an outer diameter of 16mm, the installation hole diameter can be designed to be 16.1-16.3mm.
The depth of the installation hole is also crucial. It should be able to fully accommodate the heating tube and reserve a certain amount of space for installing the sealing device. If the installation hole depth is not sufficient, the heating tube may not be fully inserted, resulting in some of the tube body being exposed outside the mold, which not only affects the heating effect but also poses a safety hazard.
2、 Heating tube layout design
The layout of heating tubes inside the mold should be uniform. This is to ensure uniform heating of the mold and avoid local overheating or excessive temperature gradients. For example, for flat molds, heating tubes can be arranged in an equidistant and parallel manner; For molds with complex shapes, it is necessary to determine the optimal heating tube layout through simulation analysis software based on the geometric shape and thermal conductivity characteristics of the mold.
At the same time, the spacing between heating tubes should be considered. Too small spacing can lead to excessive heat concentration, which may damage the heating tube and mold; If the spacing is too large, it will cause insufficient heating in certain areas of the mold. The general spacing should be determined based on the power of the heating tube and the thermal conductivity of the mold material, usually between 2-5 times the outer diameter of the heating tube.
3、 Die material selection and heat conduction characteristics
The thermal conductivity of mold materials is an important factor that cannot be ignored in mold design. If the thermal conductivity is low, it will affect the heating efficiency of the heating tube and prolong the heating time. For example, in some injection molds that require high heating speed, materials with high thermal conductivity such as aluminum alloy are chosen. At the same time, the mold material should also have good high temperature resistance to withstand the high temperature generated by the heating tube heating for a long time.
4、 Sealing and insulation design
Due to the high temperature generated during the operation of the heating tube, the mold needs to have a good sealing design to prevent heat loss and leakage of liquids and gases. High temperature resistant sealing materials such as silicone gaskets should be used at the contact area between the heating tube and the installation hole.
In addition, the insulation design of the heating tube also needs to be considered for the mold. Ensure sufficient insulation distance between the heating tube and other metal parts of the mold to avoid short circuits and ensure the safe operation of the heating tube and mold. In short, considering these special requirements during mold design is crucial for the effective use of mold heating tubes.
