Characteristics and advantages of micro foaming injection molding products
comparison with conventional injection molding products
by analyzing the existing foreign micro foaming injection molding machines that use trexel's patents and comparing the relevant data, it can be seen that compared with conventional molding products, the average cost of micro foaming molding products can be reduced by 16%-20% except for purchasing licenses and increasing equipment investment. This is mainly achieved through four aspects:
1 The cycle time of micro foaming injection molding can be reduced by 50%, thus reducing the processing cost. At the same time, the proportion of leftovers of injection molding products is reduced, and the energy consumption of the equipment is also lower
2. For the same type of products, the micro foaming injection molding process can use smaller and fewer machines, and the mold cost is lower, thus reducing the investment cost
3. Because the density of micro foaming injection molded products is reduced, products with more thin-walled structure can be designed to reduce the material cost of products
4. Due to the reduction or elimination of the internal stress in the mold caused by conventional molding in the process of mold closing and pressure maintaining, micro foaming injection molding can prepare products with flatter, straighter and higher dimensional accuracy, thus providing greater space for the improvement of product quality and price
comparison with other injection molding processes
many other injection molding processes also use or involve gases or foaming agents. These processes mainly include structural foaming injection molding, gas assisted injection molding and chemical foaming molding
micro foaming injection molding and structural foaming injection molding
Structural foaming injection molding is usually used to mold larger products. The most common is to use special low-pressure injection molding machine to process high-density polyethylene (HDPE) raw materials. The weight of its products can be reduced by 10% or more. Micro foaming injection molding has more advantages than structural foaming injection molding in some aspects. For example, for most materials, including commonly used engineering plastics, the reduction of materials and the reduction of injection cycle time are more significant. Micro foaming injection molding can form both thin-wall and thick-wall structures, which makes the product design more flexible. However, micro foaming injection molding does not have many advantages for products with large aspect ratio and thick wall (more than 6mm) products
micro foaming injection molding and gas assisted injection molding
gas assisted injection molding can mold products with very high surface quality. Through special design of molds and products, gas assisted injection molding can be realized by designing cavities in the interior of thick wall products. Micro foaming has no advantage for the molding of thick wall products, and the surface quality of its products cannot be very perfect
however, gas assisted injection molding is usually only used to eliminate the shrinkage marks of products, so in this regard, micro foaming injection molding may be a better choice, which can reduce the weight of products more, form in a shorter cycle time, and reduce the warpage of products, and eliminate the shrinkage marks at the same time
micro foaming injection molding and chemical foaming molding
chemical foaming agent decomposes at a specific temperature to produce gas foaming agent. Different types of foaming agents are suitable for decomposition and foaming at different temperatures. It is usually used for forming thick wall products to eliminate shrinkage marks, and at the same time, it can also reduce the density of products. The use of chemical foaming agent for thin-walled products will degrade the surface quality and significantly reduce its mechanical properties. Moreover, from the economic point of view, chemical foaming can not significantly reduce the operation process of Jinan gold assay pressure testing machine will encounter many errors. How to analyze and understand the error density of the pressure testing machine
the advantage of micro foaming injection molding is that many endothermic chemical foaming agents will generate water (also CO2 gas), so it is necessary to add water absorbent to prevent the degradation of polymer melt due to the presence of water. The different batch numbers of gas blowing agents make it necessary to adjust the production process at any time in the production process. In addition, due to the poor thermal stability of chemical foaming agents, it is difficult to process high-temperature resins. Chemical foaming agents usually have residues in the resin or produce by-products due to chromatic harmony. Resins with by-products or undissolved chemical foaming agents usually reduce the aging resistance of products. The Beijing Shanghai high-speed railway is 1318 kilometers long and may cause blockage of mold exhaust holes. And they will not try it with real guns, and it is difficult to recycle the leftovers produced in the processing process
of course, micro foaming injection molding technology is not perfect. For products requiring strong transparency and very high surface quality, the use of micro foaming injection molding technology needs to be more careful
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