It is baby care production for our France two shot moulding ltd in Lyon. The hard plastic part is medical grade PP and colored section are the medical grade TPE material. The production need a lot of testing included the olive oil contact testing, the aging testing and medical grade sterilization with packing. Asia Billion are the subcontractor for this project from final design , molding making , mass production to final delivery production.
Project details as below :
two shot moulding ltd
Core surface finish:
|high polihsing & texture|
Cavity surface finish:
High polishing & texture
No of Cavities:
Type of gating:
Lead time for T1:
Mold base steel:
Total Mold Price Totally:
1） Two shot moulding ltd for medical and food production
2) Crazy surface finishing requirements and flash control
3) Customized different color for soft TPE material
4) Special testing such as olive oil testing and sterilization testing with medical grade
Asia Billion Advantages for this project:
1） 20% lower price than your current suppliers
2) Difficult design and structure which made by Asia Billion from customer side sketch drawings
3) Interchangeable core and cavity for different version and productions
Asia Billion 2 shots over mold Process showing:
Asia Billion 2 shots over mold Engineering and Project Capacity:
2 shots over mold Workshop Overview:
Packing and Logistics:
The basic principles of 2 shot injection over mould design ( part two)
16. If it is a two-shot mould , it is a straight barrel, a 90-degree barrel shot, no need to rotate, only one core, soft and hard glue separation method by row seal gum.
17. The two shapes of the cavity are different, forming one product separately. The core's two shapes are the same.
18. After the front and back molds of the mold are rotated 180° from the center, they must be matched. This check must be done during design.
19. Pay attention to the position of the ejector pin with a minimum spacing of 210mm. Large molds must properly increase the number of jack holes. Moreover, since the thimble attached to the injection molding machine itself is not long enough, it is necessary to design a long ejector pin in our mold, and the thimble grows about 150 mm from the base of the mold base.
20. Two positioning rings must be designed on the back plate.
21. The total thickness of the front mold panel plus the a board shall not be less than 170 mm. Please carefully review other reference data for this type of injection molding machine, for example, maximum die thickness, minimum die thickness, and top hole spacing.
22. The depth of the front sprue should not exceed 65mm. The interval from the top of the upper side (large nozzle) sprue to the center of the mold is not less than 150 mm.
23. When designing the cavity of the second injection molding, in order to prevent the cavity from inserting (or rubbing) the glue position of the product that was formed for the first time, a partial avoidance can be designed. However, it is necessary to carefully consider the strength of each sealant position, that is, in the injection molding, whether there will be deformation of the plastic under the large injection pressure, which may lead to the possibility of the second injection.
24. When molding, the first injection molded product can be slightly larger in size so that it can be pressed tighter with another cavity during the second molding to reach the sealant.
25. Before the a and b plates are closed, pay attention to whether the front mold slider or lifter will first reset and crush the product. Therefore, it is necessary to make the method to clamp the a and b plates first, then the slider or lifet of the front die. Talent reset.
26. The transport of the two cavity and core is as full as possible and balanced.
27. 99% of the cases are the hard rubber part of the first injection molding product, and the soft rubber part of the re-injection product. Because the soft rubber is easy to deform.
28. Pay attention to whether the plastic activity will be impulsive in the second injection molding, and the plasticity will be deformed. If you have this possibility, you must improve the method.
29. Two-color molds must be carefully selected for the gate location. It is best to choose a latent glue in one product so that the product and runner can be cut off automatically. Three-plate molds or hot runner molds can be considered when latent feed cannot be used. If the material is a point gate, do a wave, to avoid hitting the secondary material due to one entry residue.
30. Two-color injection molds often use rotary injection molds. The punch/die at two positions of the rotary injection mold requires uniform size and precision, and works well with the die/emboss. When the ejection mechanism on the two-color injection molding machine cannot be utilized, a hydraulic ejection and release mechanism must be provided on the rotary table.
31. Two-color mold injection molding usually uses the same plastic of different colors, or two different plastic raw materials. At this time, it is necessary to consider the interface effect, shrinkage difference, processing parameters and other aspects of the two materials.
Two-color injection molding products are generally made of hard plastics such as abs and pc, and tpe soft plastics. Due to the cost or application, it is necessary to fully consider the two materials that may be used without good adhesion and fusion. Mold treatment at the joint (generally there will be a phenomenon of embossing the road or need to be used to seal the groove) and the thickness of the material and so on! In order to make the two plastics "sticky" tighter, we must think about the "between the materials" Viscosity and the roughness of the mold surface. Two-color injection molding has a special tpu material; the smoother the mold appearance, the more tightly they stick.
32. In general, the shrinkage rate of a two-color mold depends on the primary material. Because the primary material has already supported the contours of the plastic product, the secondary material does not shrink more. As for how to determine the primary and secondary materials, there are many factors to consider, such as the fluidity of the raw materials, the shape of the plastic products, and so on.
33. Pay attention to the positioning of the front and rear molds; all the insertion and the slope of the broken surface should be as large as possible, and should be 0.1mm or more.
34. ABS/PC, ABS/PC ABS, ABS/PMMA two-shot injection moulding, you need to first injection high temperature pc, pc abs or pmma. In the case of a transparent face shell mold, most of the flip mold structures are used.
35. Transparent large two-color injection molding is a place to pay attention to structural design:
a. The reservation of the gate location must be agreed in advance with the mold factory;
b. The thickness of the material is recommended to be transparent 0.8mm or more, non-transparent 0.7mm or more, non-transparent as far as possible to use light color, when there is a led light, pay attention to shading;
c. The width of the parting surface of the transparent part and the hole are the same, the width is recommended to be 0.5mm, the surface is smooth, avoiding the side view, can pass through far, unsightly, and minimize the hole;
d. The thickness of the non-transparent parts is limited, and the structure of the upper ribs and the like is as far as possible between 0.5 and 0.6 mm to avoid shrinkage;
e. For the current time, it is not recommended to do two-color injection molding with main lens. The cost of mold and product is too high. There are quite a lot of requirements for the equipment and technical level of the mold manufacturer. If you do, you need to give the whole solution a detailed solution for the whole process. For evaluation, the intermediate links need to be reviewed;
f. For large-area two-color injection molded parts, two key tests are drop and thermal shock. In both tests, the transparent and non-transparent parts are easily disengaged. Hot and cold shock -40 -65, time 48 hours.
g. The structure on the two-color parts should be as simple as possible, and the complex parts should be made above the matching parts. The width of the ribs of the non-transparent parts should be 0.5-0.6 as much as possible to avoid shrinkage.
Asia Billion can help you for your two shot moulding tooling project from intial design , design improvement , prototype making , mold fabrication, 2k injection moulding and final approved production with testind and packing . let us know free for your ideals to realize your production with competitive advantages for marketing damanding.