What are the injection molding processes that affect the strength of electric injection molding machine?
electric injection molding machine is the main molding equipment for plastic production. It uses plastic molding molds to make plastic products of various shapes from thermoplastics or thermosets. Injection molding is achieved through injection molding machines and molds.
Several injection molding processes that affect the strength of electric injection molding machine:
Compared with other hard rubber materials, PP material is more elastic, so the density of injection molded parts will increase with the increase of pressure. This characteristic is relatively obvious. When the density of a plastic part increases, its tensile strength will naturally increase, and vice versa. However, when the density increases to a certain value that PP itself can reach, and then increase the pressure, the tensile strength will not continue to increase, but will increase the residual internal stress of the injection molded part, making the injection molded part brittle, so it should be adequate.
Under normal circumstances, the PVC 90 degree material is injected at 180 ℃, and the temperature is sufficient, and generally there will be no problem of raw rubber. However, it is often due to reasons that have not attracted the attention of the operator, or deliberately speeding up the melt speed in order to speed up production, which makes the screw retreat quite fast. For example, it only takes two or three seconds to retract the screw to half the melt volume. In more than one position, the time for the PVC material to be heated and stirred is seriously insufficient, causing the melt temperature and uneven mixing of the raw rubber, which makes the strength and toughness of the injection molded part quite poor.
Therefore, when injecting PVC materials, be careful not to adjust the melt speed to more than 100 rpm. If you must adjust it very quickly, remember to increase the temperature of the material by 5 to 10°C, or increase the back pressure of the melt to match. At the same time, you must always check whether there is any problem with the raw rubber, otherwise it may cause Significant loss.