Judgment precision injection molding is based on the accuracy of injection products, the products of the size tolerance, geometric Tolerance, and surface roughness. To be precise injection must have many related conditions, and the most essential is a plastic material, injection mold, injection molding process and injection equipment which four fundamental factors. Design of plastic products, should be first selected engineering plastic material, and for precision injection molding engineering plastics must choose those high mechanical properties, dimension stability, good creep resistance, and resistance to environmental cracking stress of the material. Second, the selection should be based on plastic material, the dimensional accuracy of the finished product, the piece weight, and the quality requirements and the desired mold structure selected suitable injection molding machine. In the process, the factors affecting precision injection molding products mainly from the accuracy of the mold, injection molding shrinkage, and the ambient temperature and humidity range of products, etc.
In precision injection molding, the mold is one of the key used to obtain the required quality precision plastic products; precision injection molds should earnestly comply with the product size, accuracy and shape requirements. But even if the mold precision; uniform size; the actual size of its molded plastic products due to shrinkage of the differences will be inconsistent. Therefore, effective control of plastic shrinkage in precision injection molding technology is very important.
Mould design is reasonable or not will directly affect the plastic shrinkage rate, due to the size of the mold cavity is made of plastic products plus the estimated size shrinkage obtained, the shrinkage rate is a range of values made of plastics manufacturers or engineering plastic manual recommends. It is not only related to the form of the mold gate, the gate location and distribution, but also with plastic crystal orientation (anisotropy), plastics shape, size, and distance to the location of the gate. The influence of plastic shrinkage rate mainly heat shrinkage, contraction phase change, orientation shrink, compression shrinkage and elastic recovery factors, and these influence factors about precision injection parts molding conditions or operating conditions.
Therefore, when designing the mold must consider the relationship between these factors and Injection molding conditions as well as the apparent factors. Such as injection pressure and cavity pressure and mold filling speed, Injection molding-Melt temperature and mold temperature, the mold structure and the form and distribution of the gate, and the gate cross-sectional area, wall thickness, the content of reinforcing filler in plastics materials, Plastic materials of orientation and orientation and other factors. The above factors also because of the different plastic materials, other molding conditions such as temperature, humidity, and continues to crystallize, after the changes in the stress of the molding, the injection molding machine are different.
Because the injection molding process is the process from the solid (powder or pellets) to liquid (melt) ED solid (product) change. From pellets to melt, then by the melt to the products, middle should through flow field and temperature field, stress field, density field and so on, under the combined effect of these fields, different plastics (thermoset or thermoplastic, crystalline non-crystalline, enhanced or non-reinforcing type, etc.) have a different polymers morphology and rheological properties. Any of these factors affect the "field" is bound to affect the physical and mechanical properties of plastics, size, shape, accuracy and visual quality.
Thus, the intrinsic link process factors and polymer properties, morphology and plastic products will be demonstrated by between plastic products. Analysis of these internal relations, reasonably intended for injection molding process, reasonably design and manufacture of moulds according to the drawing, and reasonably choose the injection molding processing equipment are important. Precision injection molding and injection molding ordinary on the injection pressure and injection rate also have difference Precision injection molding is often used high-pressure or high pressure injection, high speed injection in order to obtain the smaller molding shrinkage rate. Taking these various reasons, design precision injection molds, besides consider the design elements of the general mould, they also need to consider the following points: ① appropriate mold size tolerance; ② prevent mold shrinkage error; ③to prevent plastic deformation; ④ prevent mold deformation; ⑤ minimize mold manufacturing error; ⑥ prevent mold precision error; ⑦ keep the mold accuracy.
As metal stamping, LED bracket precision high-speed continuous mode of development and processing industry, Heju been executed [fast, accurate and stable] work commitments, in the field of terminals, connectors, steel, precision sheet metal parts, has been dedicated and committed to Convey the mold manufacturing technology and offers fine, beautiful, inexpensive, excellent stamping parts and precision parts, constantly cultivating technology, and strive to meet and exceed customer expectations.
In precision injection molding, the mold is one of the key used to obtain the required quality precision plastic products; precision injection molds should earnestly comply with the product size, accuracy and shape requirements. But even if the mold precision; uniform size; the actual size of its molded plastic products due to shrinkage of the differences will be inconsistent. Therefore, effective control of plastic shrinkage in precision injection molding technology is very important.
Mould design is reasonable or not will directly affect the plastic shrinkage rate, due to the size of the mold cavity is made of plastic products plus the estimated size shrinkage obtained, the shrinkage rate is a range of values made of plastics manufacturers or engineering plastic manual recommends. It is not only related to the form of the mold gate, the gate location and distribution, but also with plastic crystal orientation (anisotropy), plastics shape, size, and distance to the location of the gate. The influence of plastic shrinkage rate mainly heat shrinkage, contraction phase change, orientation shrink, compression shrinkage and elastic recovery factors, and these influence factors about precision injection parts molding conditions or operating conditions.
Therefore, when designing the mold must consider the relationship between these factors and Injection molding conditions as well as the apparent factors. Such as injection pressure and cavity pressure and mold filling speed, Injection molding-Melt temperature and mold temperature, the mold structure and the form and distribution of the gate, and the gate cross-sectional area, wall thickness, the content of reinforcing filler in plastics materials, Plastic materials of orientation and orientation and other factors. The above factors also because of the different plastic materials, other molding conditions such as temperature, humidity, and continues to crystallize, after the changes in the stress of the molding, the injection molding machine are different.
Because the injection molding process is the process from the solid (powder or pellets) to liquid (melt) ED solid (product) change. From pellets to melt, then by the melt to the products, middle should through flow field and temperature field, stress field, density field and so on, under the combined effect of these fields, different plastics (thermoset or thermoplastic, crystalline non-crystalline, enhanced or non-reinforcing type, etc.) have a different polymers morphology and rheological properties. Any of these factors affect the "field" is bound to affect the physical and mechanical properties of plastics, size, shape, accuracy and visual quality.
Thus, the intrinsic link process factors and polymer properties, morphology and plastic products will be demonstrated by between plastic products. Analysis of these internal relations, reasonably intended for injection molding process, reasonably design and manufacture of moulds according to the drawing, and reasonably choose the injection molding processing equipment are important. Precision injection molding and injection molding ordinary on the injection pressure and injection rate also have difference Precision injection molding is often used high-pressure or high pressure injection, high speed injection in order to obtain the smaller molding shrinkage rate. Taking these various reasons, design precision injection molds, besides consider the design elements of the general mould, they also need to consider the following points: ① appropriate mold size tolerance; ② prevent mold shrinkage error; ③to prevent plastic deformation; ④ prevent mold deformation; ⑤ minimize mold manufacturing error; ⑥ prevent mold precision error; ⑦ keep the mold accuracy.
As metal stamping, LED bracket precision high-speed continuous mode of development and processing industry, Heju been executed [fast, accurate and stable] work commitments, in the field of terminals, connectors, steel, precision sheet metal parts, has been dedicated and committed to Convey the mold manufacturing technology and offers fine, beautiful, inexpensive, excellent stamping parts and precision parts, constantly cultivating technology, and strive to meet and exceed customer expectations.
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