In traditional molds, cooling waterways generate an internal network through cross-boreholes and adjust the flow rate and direction through an internal fluid plug.The application of metal 3D printing technology in mold cooling waterway manufacturing has broken through the limitation of cross drilling on cooling waterway design.Now, mold design companies can design shaped waterways that are closer to mold cooling surfaces, with smooth corners, faster flow rates, and higher cooling efficiency.
1. Diameter of waterway
Conventional cooling waterways, typically 7/16 inches in diameter, are made by drilling holes.If the diameter of the cooling water channel is too large, it may cause the water channel to be difficult to reach the surface of the mold and avoid the mold parts.If the diameter is too small, bit drift may occur during water processing.Although the additive manufacturing technique avoids some of the limitations of the drilling method, it is still necessary to reduce the uncertainty of the technique by setting the diameter within the range of commonly used and proven dimensions when designing waterways.
2. Cross sectional area
When the cooling waterway is processed by drilling, the cross-sectional area of the waterway remains unchanged.Although it is possible to create a water channel with many different shapes through 3D printing technology, the cross-sectional area of the water channel should be kept constant when designing the 3D printing shaped cooling water channel, so as to ensure the constant volume of cooling liquid passing through the water channel.
3. Distance from the mold surface
For the distance between the cooling waterway and the surface of the mold, there is no fixed provision. For example, some enterprises retain the distance exactly equal to the distance of the waterway diameter in the design, while some retain the distance twice of the waterway diameter.
For most form-dependent cooling waterways, the distance from the mold surface depends on the geometry of the part.In the design of the distance from the surface of the mold, there is a principle to be observed, so that the shape of the waterway and the mold surface always keep the same distance, so as to achieve a uniform cooling effect.
4. Length of cooling waterways
Drill bit drift or damage may occur if debris generated during drilling is not drained during drilling of cooling waterways.In such cases, cooling waterways are chosen to be as short as possible.
Although 3D printing technology can be used to manufacture the shaped cooling water channels without any problems such as tool damage, it is still not recommended to design the water channels too long.This is because cooling water can flow in and out more quickly in shorter cooling waterways, making heat distribution more even.
5. Another rule of cross-sectional area
Because several short cooling waterways can cool more uniformly, some of them are designed according to the idea of capillary, that is, a large cooling waterway is divided into several small and short waterways, and then merged into a large cooling waterway.In this case, the total cross-sectional area of a number of small waterways should be equal to the cross-sectional area of the inlet and outlet of a large waterway to ensure uniform water flow and further reduce the risk of warpage.
6. Rotating structure
The water amount in the mold cooling water channel is the factor that affects the mold cooling time. The greater the water amount is, the shorter the cooling cycle time is.Another factor is water turbulence.Although the inner surface of the 3D printed cooling waterways is not polished, more turbulence can be generated if the rotating structure is added to the design.
The above design rules are not all the rules that need to be paid attention to for the success of 3D printing of shaped cooling waterways.Mold manufacturing users should have a systematic understanding of injection mold manufacturing when designing 3D printing and shaped cooling water channels.There are many valuable experiences in the traditional design principles of mold cooling waterways, which are the basis for the effective design of 3D printing shaped cooling waterways.
Source: Future Works