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With the development of science and technology, plastic injection moulds have become an essential tooling of producing plastic products in plastic products manufacturing industry. In our real life, plastic products have almost captured all fields. Whether it is the parts of aircraft and cars or some of the commonly used toothbrushes and cups in our daily lives. In fact, those plastic products that are commonly used around us are not produced by the manufacturer one by one according to the drawings, but are produced in batches through plastic injection moulds.

Before the plastic injection moulding manufacturer produce plastic products, the injection mould of this product will be made in advance. After the injection mould is completed, the manufacturer can mass-produce through this mould. Is the plastic injection mould manufacturing process complicated?

In fact, the plastic injection mould manufacturing process is very precise and complicated, because in the real life, plastic injection moulds are applied to various plastic injection moulding products, and many plastic moulded products must be manufactured accurately, such as plastic bottle mouths and caps. The production of them needs to be very delicate, because if there is a little inconsistency, it can't be combined. Therefore, when making plastic injection moulds, it is necessary to pay attention to such problems. The injection moulds must be made very precise which is possible to make high-quality plastic injection moulding products. Of course, for those plastic products that are relatively large and inexpensive, there is no high process requirement. For example, the mould of plastic basin doesn't require too strict requirements for the manufacturing process.
Plastic Injection Mould Factory

The following problems should be noted when making plastic injection mould:
  • Don’t just focus on injection moulding products design, ignore injection mould making.
  • Don't just pay attention to prices. Should have overall consideration from injection mould quality, production cycle, and injection moulding company service.
  • Avoid multi-head collaboration, try to make plastic injection mould making and plastic injection moulded parts processing integration.
The ejector system has a variety of forms. It relates to the shape, structure and plastic properties of the product. Generally, there are ejector pins, jacking tubes, push plates, ejector blocks, pneumatic composite ejectors, etc. The design principles of the ejector system are as follows:
  1. When selecting the parting surface, try to keep the product on the side of the mould release mechanism.
  2. Top output and position balance to ensure that the product is not deformed, not broken.
  3. The thimble should be located where it does not affect the appearance and function of the product.
  4. The use of standard parts as far as possible is safe and reliable for manufacturing and replacement.
  5. The ejection position should be set at a large resistance, not too close to the insert or core. For box type and other deep cavity moulds, the side resistance is the largest and the top surface and side surface should be ejected at the same time so as to avoid deformation of the product.
Injection mould is a tool by injection mould factory used to produce plastic products. It refers to the melted plastic injected into the cavity by injection moulding machine, then formed after cooling and curing. In the process of mould manufacturing, it is very important to determine the delivery date of the moulds, so what factors are related to the time of making the injection mould? So let me introduce to you.
The mould releasing difficulty often encountered in the process of injection moulding, it has a very large influence on the quality of injection moulding products. It may cause the scratch or pattern of the product surface, even can lead to product warp and even rupture damage. Therefore, it is necessary to solve the problem of mould releasing, which affects the quality of the final injection moulding product. The solution is considered in the following aspects:
Produce a high quality of injection mould, not only need good injection mould processing equipment and skilled injection mould manufacturing workers, another important factor is to have a good injection mould design, especially for complex injection mould, injection mould design quality accounts for more than 80% of the injection mould quality. A good injection mould design is: in the premise that meet guests' requrement, the processing cost is low, the processing difficulty is small, and the processing time is short.
Injection moulds are parts that give plastic shape and size in moulding. Although thestructure of the mould may vary due to the variety of plastics and properties,the shape and structure of the plastic products and the type of injection machine,but the basic structure is consistent.
With the rapid development of injection mould industry in recent years, at the same time, new technology, new technology application range widening and progress, from traditional experience to the application of software development has been a qualitative change. Wide application of CAD, CAM and CAE for our injection mould and injection mould product geometry control technology opened up the space, due to the injection mould and injection mould product market demand difference is very big, wide variety, in shape, size, material, the change of structure and so on various aspects, and demand is high, we in the injection mould and product production encountered many problems and difficulties in the process, including how to effectively control the geometry size of injection mould and products is directly in front of us.
It is necessary to check and verify the easily damaged plastic injection parts and register them. Reserve the amount of inventory that may be consumed within 4 ~ 5 weeks, and record the damaged parts that have been replaced. Perform the inspection of common auxiliary equipment, and take a photo to record the position of the injection mould assembly.
The most common cause of black streak is the material residue in the injection moulding machine barrel.Residue remains in the plunger injection moulding machine.For valve gated injection moulding machine, the valve-regulated part also tends to remain residue.The air is compressed to a high temperature in the cylinder, with the high temperature gas in the gate, so it will be easy to be black streak.
Black Streaks
Residual gas inside the injection mould is compressed into high temperature state and burn the material.
Insufficient air discharging will cause burn mark.
Insufficient air discharging will also cause material shortage.
Burn Marks
In the nozzle and side slip, cooled resin flow into the mould cavity in a semi-cured state. After contact with the injection mould, the resin immediately cured, and then into a deep cavity formed flow mark.Different thickness of the plastic parts can also cause flow mark.
Flow Marks
Using only one sprue (gate), without confluence the material from two directions, in this way the molded parts generally do not have weld line. If you want to avoid weld lines, you can only change the position of the sprue in the injection mould so that the welding mark will not occur in obvious places.
Change the location of the sprue in injection mould
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Online tour of our plastic injection mould making factory in Shenzhen China.
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