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Plastic injection mould made of steel can manufacture millions of plastic parts, but the plastic mould making time is long, and the cost of injection moulds made of steel is high. While when it is large volume injection moulding, and the production quantity of injection moulded parts increases, the cost will be lower accordingly. The hardness of the plastic moulds made of steel is high, the wear resistance of injection moulds is good, and the mould service life is long. Generally, the plastic injection mould made of mould steel can operate for 10,000 times, is suitable for long-term large volume injection moulding. Multi-cavity moulds larger than 8 cavities can increase the complexity of mol parts. The mirror polishing performance of injection moulds is good.
Steel moulds for large volume injection moulding
ACO Mold technical requirements for automotive injection moulds are as follows:
1. Analysis of product moulding process, automotive injection mould structure and automotive injection moulding process. Guarantee the service life of automotive injection moulds up to 1 million times.
2. It is necessary to design a complete automotive injection mould structure and machined parts, and to propose assembly requirements and injection moulding process requirements.
3. Causes defects in the appearance quality of plastic parts (such as shrinkage, etc.) or mould structure problems of auto parts (such as parting surface setting, gate setting, mould service life cannot be guaranteed, etc.).
There may be cracks of the injection moulded parts during the injection moulding process, so what caused the cracks of the injection moulded parts? Let's look at these aspects:

Injection moulding process
(1) If the processing pressure is too large, the speed is too fast, the feeding amount is too large, the injection and the pressure holding time are too long, and then the internal stress will be too large, which will cause cracks of injection moulded parts.
(2) Adjusting the mould opening speed and pressure to prevent demoulding cracking caused by quickly forcibly pulling out injection moulded part.
(3) Appropriately increase mould temperature to make injection moulded parts easy to demould, and appropriately reduce material temperature to prevent decomposition.
Cracks of injection moulded parts
In plastic moulding, a representative moulding method is injection moulding, so the demand for injection moulds is large. However, injection moulds usually made of mould steel are costly, so injection mould are suitable for large volume injection moulding. As the product update cycle continues to shrink, the number of plastic parts produced in small batches continues to increase. In addition, in the production of product tests, plastic parts produced in small batches are also required. For example, the number of plastic parts used for testing is usually 100 pieces, the number of plastic parts used for trial assembly is usually 10 pieces, the number of plastic parts for batch trial production is usually 1000 pieces, and the number of plastic parts used for low volume plastic injection moulding is 5000 pieces.

In order to meet the needs of low volume plastic injection moulding, various injection moulds suitable for low volume plastic injection moulding have been developed. This type of mould is characterized by a short mould making cycle and low injection mould cost, but it can meet the requirements of small batch production.
Low volume plastic injection moulding
ACO Mold is one-stop China injection mould manufacturer that provides plastic injection mould design &manufacturing, injection moulding, surface coating, electroplating and product assembly. We have more than 9,000 square meters of standard manufacturing plant, equipped with a full set of precision mould processing workshops and ordinary mould processing workshops, measuring instrument testing laboratory, injection moulding workshop, providing customers with one-stop high, medium and low-end injection moulds manufacturing & Injection Moulding & Product Assembly Services to meet customer product development needs. The factory is equipped with a series of equipment such as CNC machining center, engraving machine, spark machine, wire cutting, grinding machine, milling machine, drilling machine and lathe etc.

Do you have the following problems when customizing plastic products?
---Mould type selection: Can't grasp the product features
---Injection mould price: The price is too high to accept
---Mass processing: Injection moulding quality is unstable
---Injection moulding products spraying: The appearance of injection moulding products does not meet the requirements
---Slow delivery: Cannot be delivered on time and in volume
Injection mould
Choose ACO Mould as your partner in injection moulding, these problems will be solved!
1. Professional mould type selection:
We have a variety of private mould, and have 1000 + mould design experience, so we can fully understand the product characteristics of various industries, to provide customers with excellent mould type selection services.
2. Competitive price
Our injection molds are very cost-effective, so ACO Mold can provides you with a more reasonable, more competitive and lower price.
Rapid Tooling (is also known as rapid injection moulding) is a tool that shapes a product of a certain shape, size, and surface accuracy in its specific shape. It is mainly used in large-scale production. Although the production and manufacturing costs of moulds are relatively high, the cost per product is greatly reduced due to mass production.
In order to meet the customer's schedule requirements, and the product size and surface have a good consistency, speeding up the development and verification of the product, the rapid mould manufacturing within 100-1000 sets can be satisfied here.
Rapid injection moulding
Most people think that 3D printing is a good substitute for injection moulding that requires mould making. Is this really the case? At the moment, 3D printing has already had a huge impact on the manufacturing industry. The prototype that used to cost a few hundred dollars and took weeks to process can now be designed in the morning, printed at night, and delivered to customers the next morning.
What is injection moulding?
Injection moulding is a processing method used in mass production of plastic parts with complex shapes. The advantages of the injection moulding are fast production speed, high efficiency, automatic operation, variety of colors, shapes from simple to complex, the size can be from large to small, and the size of the injection moulded part is accurate, the product is easy to be replaced, and injection moulded parts with complex shape can be moulded.
At a certain temperature, the completely molten plastic material is stirred by a screw, and the molten plastic material is injected into mould cavity by high pressure. After cooling and solidifying, the injection moulded parts can be obtained. The injection moulding is one of the importance plastic processing methods.
The plastic injection mould processing is to first add the plastic into the mould, and then the mould is continuously rotated and heated along the two vertical axes. The plastic in the plastic injection mould is gradually uniformly coated and melted and adhered to the entire cavity surface under the action of gravity and heat energy. It is moulded into a desired shape and is obtained by cooling and setting. The characteristics of plastic injection mould processing are as follows:
In order to meet the requirements of small and light injection moulded parts manufacturing, thin-wall injection moulding has become the most important injection moulding process. According to the definition of lightweight electronic plastic parts, "thin wall" means that the wall thickness is less than 1 mm. For large automotive plastic parts, the "thin wall" can be 2 mm. In summary, thin-wall injection moulded parts require changes in the processing process, higher pressures and speeds, shorter cooling times, and changes in part ejection and gate arrangement. The change of processing technology has also promoted the development of plastic injection mould, injection moulding machine and injection moulded parts design, and put forward higher requirements for injection moulding machines and injection moulds.
injection moulded thin wall products
The plastic injection moulding process is a cycle process. Once the once cycle is completed, the once injection moulding cycle is completed. Each cycle mainly includes quantitative feeding, melt plasticizing, pressure injection, mould filling, cooling, and mould opening and removal of injection moulded parts. After removing the plastic part, the mould is closed and the next cycle is performed. Each time the injection moulding cycle is completed, the injection device and the clamping device of the injection moulding machine respectively complete once working cycle, that is, the moving parts of the injection device and the clamping device are sequentially operated once in a predetermined order. There are 3 keys stages to complete injection moulding: plasticization, injection, and moulding.
injection moulding
Main moulding conditions of PE:
  1. Barrel temperature: The temperature of barrel is mainly related to the density of PE and the flow rate of melt. It is also related to the type and performance of the injection moulding machine and the shape of the first-class plastic part. Since PE is a crystalline polymer, the crystal grains absorb a certain amount of heat during melting, so the cylinder temperature should be 10 degrees higher than its melting point. For LDPE, the cylinder temperature is controlled at 140-200 °C, the HDPE barrel temperature is controlled at 220 °C, the temperature of the rear of barrel is taken as the smallest value, and the temperature of the front of the barrel is taken as the largest value.PE Plastic
  2. mould temperature: The mould temperature has a great influence on the crystallization condition of plastic part. The mould temperature is high, the melt crystallinity is high, and the strength is high, the shrinkage rate will increase accordingly. Generally, the mould temperature of LDPE is controlled at 30 ° C - 45 ° C, and the temperature of HDPE is correspondingly higher by 10-20 ° C.
  3. Injection pressure: Increasing the injection pressure is conducive to the filling of the melt. Since the fluidity of PE is very good, in addition to the thin-walled slender products, the lower injection pressure should be selected well, and the general injection pressure is 50-100 MPa. For the plastic parts with simple shape and large wall thickness, the injection pressure can be lower.
In order to ensure the smooth process of injection moulding and make the plastic moulded products quality meet the requirements, a series of preparatory work must be done before plastic injection moulding, including the inspection, coloring and drying of raw materials, the cleaning of material barrel, the preheating of inserts and the selection of demoulding agents.
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