We produce mainly include these two types, independent development design products and OEM products.
Plastic product design and development
According to the demand of market, we continuously develop structural members that meet the requirements of international consumers. As customers enhance the requirement of world plastic production, the competition in the injection molded plastic market is getting more and more intense. Therefore, we can learn that there should be unique features of our consumer plastic products to attract our clients. Certainly, the structural component our engineer design should be special in terms of appearance, structure and function. When you cooperate with our injection molding engineer, they provide professional knowledge and considerable service. What’s more, as a engineering products company, we try our best to help you reduce thermoforming cost. Then it can create the biggest profits for your company.
Originally, OEM means that the customer provides all technical data and drawings. At the same time, plastic parts manufacturers are only responsible for plastic parts production. In fact, OEM we now mention also includes that the customer requests for appearance and function. And we China plastic products manufacturers go on injection molding part design and global plastic production according to their requirements. When it comes to OEM products, we always design and produce structural members by following the customer’s requirements.
Only under the circumstance that customers’ requirements is not reasonable, we will conduct further plastic product design and development. Of course, before all of that, we should negotiate with our customers and get their permission. The signal that the entire development process of OEM products is complete is not as same as that of ODM products. It’s that we get the final confirmation of customers and we make sure our company can provide.
1. Plastic products
When the engineer designs plastic part, we think that he should try to be successful once. As we all know, it’s easy to reduce the material and difficult to add materials while repairing molding products. Therefore, we can keep a certain amount of space between the plastic parts in advance for some places, where it’s difficult to guarantee.
1.1 Introduction of commonly used plastics
Commonly used plastics mainly include many different types. For example, poly plastic products, polyethylene plastic products, PVC plastic products, PET plastic products, and POM, AS, PC, PMMA, PS, HIPS, ABS plastic products. Among all of them, commonly used transparent plastics include PC, PMMA, PS, and AS. In general, we can always see plastic enclosure for high end electronic products, which is ABS+PC. The display screen is usually PC. However, while using PMMA, we need to harden the surface of plastic parts. In daily life, there are many uses of plastic enclosures for middle and low grade electronic products, which are HIPS and ABS. And since HIPS has better anti-aging performance, there is a trend that HIPS will gradually replace ABS plastic products.
1.2 Introduction of common surface handle
Common surface handle methods of plastic injection molding process include electroplating, spraying, screen printing and pad printing. Materials of ABS, HIPS and PC have good surface handling effect. However, the surface handling performance of PP material is poor. In general, we will do the preprocessing for PP material. In recent years, many other surface handle methods during plastic parts manufacturing process have developed.
For example, in mold decoration(IMD), in mold label(IML), and HALF MIRROR manufacturing technology.Differences between IMD and IML:
The base material of IDM membrane is mostly PET of high stripping performance. And the base material of IDM membrane is mainly PC.
During the injection molding process of IMD, there is a combination of resin and the ink on the membrane. However, during the plastic injection molding process of IML, we lay the whole membrane on the resin.
The machine automatically locates the position and delivers through IMD. And we use manual operation and manually position by IML.
2. Plastic component design
We are China plastic products manufacturers. As we all know, we should be really careful during the plastic product design. If there is any mistake during the design of plastic parts, it is likely that the injection molding die will be scrapped. In general, when we start injection mold design, we hope that the appearance of finished injection molding products can be beautiful and flow. What’s more, the curved surface is smooth and natural, which accords with human body engineering.
The plastic enclosure for electronic products we usually use in real life is mainly composed of upper case and lower case. In theory, the shape of the upper shell and the lower shell can coincide. But in fact, the dimension of the upper shell and the lower shell of the custom plastic parts are usually not consistent. Because there are some impact of the plastic products manufacturing accuracy and injection molding parameter of the custom soft plastic molds.
There are mainly two kinds of situation of dimension inconsistencies of China plastic products. Including surface scratch(the face shell is larger than the back shell) and bottom blowing(the back shell is larger than the face shell). In fact, when there is no guarantee of the difference, we should try our best to make the face shell of company products be larger than the bottom shell.
2.1 precision plastic products
As plastic products manufacturers all know, the characteristic of thermoforming plastic is that it expands when heated and shrinks when cooled. Of course, the volume of thermoformed plastic will reduce after the pressurization. During the plastic injection molding process, firstly, we inject the molten plastic into mold cavity. Then, after the filling, the temperature goes down, and the molten plastic parts become solid. At this time, the plastic part shrink when we take it out of the thermoforming die. And we call this shrink to die shrinkage.
Generally speaking, since there are more keyholes of the upper plastic shell, its amount of molding shrinkage is larger. And we choose thermoforming material with higher shrinkage for the upper shell, it’s usually 0.5%. The molding shrinkage of the lower plastic shell is relatively small. Therefore, we choose thermoforming materials with lower shrinkage for it, which is usually 0.4%. That’s all to say, the shrinkage of the surface plastic case is generally 0.1% greater than that of the bottom plastic case.
2.2 Parts design for assembly
It refers to the assembly size design between different plastic parts with assembly relations. For us plastic products company, we mainly need to pay attention to clearance fit and tolerance control of these different plastic parts for one plastic product.
2.3 Seam allowance
It refers to fitting between the upper shell and the lower shell of thermoforming products. Generally, there should be 0.05mm-0.1mm space for the nominal dimension of the injection mold design. And there should be a slope of 1.5-2°for the fitting surface of plastic product. At the end, we have set chamfering or rounded corners to facilitate the loading of the small plastic products. Through the cooperation of rounded corner of the upper and lower shell, we should make the inner angel R bigger. Then it can increase the clearance between rounded corners of composite plastic products and prevent the interference.
2.4 Snap fit
We always use snap fit to attach flexible plastic products. Including polyethylene plastic products, PVC plastic products, ABS plastic products, PET plastic products and so on. Generally speaking, when considering the amount and position of the snap fit, we should start from the overall appearance and dimension of applied plastic products. And our customers always require that the snap fit amount of prime plastic products is average and its location is balanced.
The snap fit of quality plastic products which we set on the corner should close to the corner as much as possible. Because it can make sure that there is a better combination at the corner of custom made plastic parts. What’s more, it can prevent the seam problem from the plastic product design and development, which is easy to happen at the turning point. Also, we should preserve the space when it comes to the plastic part design considerations. And it’s also pretty important to consider whether there is enough routine of the lateral axis when we start the injection molding design.
2.5 Screw stud
Plastic parts manufacturers usually use self-tapping screw for injection molded parts, which diameter is 2-3mm. And for different injection molding materials, their screw stud dimension are different. In general, the d value of injection molding materials which are soft and have better toughness is small. On the contrary, the d value will be larger.
2.6 Plastic injection mold design of structure
In terms of basic thickness design of plastic parts, it’s not appropriate to be too thin. Otherwise, the intensity of injection moulding products is not enough. Therefore, it easily leads to emergence of problems, such as shape changes and breakage. If the thickness of company products is too thick, it’s a waste of raw material for plastic injection molding. What’s more, it will affect the plastic production of injection molding process.
In general, China plastic products manufacturers control the plastic thickness of the outer enclosure under 1-2mm. And the overall thickness of outer plastic enclosures should be average. What’s more, there must be no structure with a large change in plastic thickness. Or it’s easy to cause shrink of composite plastic products appearance, especially at the bottom of the tendon and the position of the screw stud. Therefore, plastic products supplier controls the thickness between 0.6-1.2mm to prevent the shrinkage.
2.7 Keyhole design of plastic parts
There are three options for plastic parts manufacturers to choose while punching the keyhole. Each option has its advantage and disadvantage during the plastic formation process. The option A is good for the manufacturing of plastic injection molds. But it’s easy to get stuck at the edge of punching position. While option B avoids the stuck problem, other problems occur during the injection molding process steps of kissing off the offset. And option C increases diagonal foot of the key. At the same time, it saves the balance of kissing off the offset, and effectively prevent the emergence of the plastic production process problem. At present, plastic products inc usually adopt plastic production methods B or C.
2.8 Plastic part design of keys
Plastic consumer products manufacturers should pay attention to the gap between the key and plastic shell keyhole. Certainly, it’s not only during the production of plastic, but also the thermoforming mould design process. Generally speaking, if we use silicone keypad, the gap between the key and plastic case keyhole should be 0.2-0.3mm. And if using cantilever for keypads, then we should consider to preserve the deflection gap of the plastic parts.
What’s more, if there is any handle on the surface of custom keypads, plastic injection molding companies will consider their influence. Because different surface handle methods during plastic parts manufacturing process have different impact on the gap. In general, the plating thickness of electroplating is 0.1mm. And the plating thickness of both spray coating and vacuum plating are about 0.05mm.
It’s about the circle arc and rounded corner. While considering that injection molding engineer conducts the screen printing on plastic parts and so on, we should control the surface arc. In general, the circle arc on the surface of custom keypad should not be too large. And plastic injection molding companies China will control the height of arch within 0.5mm. As for rounded corner, we set it around the top of keypads to avoid stuck problem during the injection mold process.
It’s about the hand feeling, service life and deformation of custom keypad. The press power of the touch button is generally required to be 100g~200g. Also, it’s flexible to press and has a good hand feeling. What’s more, Xuzhuo Industial adopts quality molded plastics and the service life of flexible keypad is about 100,000 times. As for cantilever keypad, plastic injection molding manufacturer will strictly control its deformation during the whole process including plastic production, transportation, and storage. Because any slight deformation may cause the obvious decrease of keypad’s using effect.