How to open the exhaust in the plastic mould exhaust, should notice what?
1.2 the exhaust There are many ways to exhaust the cavity, but every method must be guaranteed: the exhaust groove should be designed to prevent the material from spilling into the slot. The second is to prevent blockage. Therefore, from the surface of the cavity of the cavity to the cavity of the cavity in the cavity of the cavity, the exhaust tank of 6 to 12mm long, the slot height should be about 0.25 to 0.4 mm. In addition, the number of exhaust slots is harmful. It is dangerous to cause cold flow or fissure in the cavity material if the mode of the lock mode is very high in the part of the cavity that is not open. In addition to outside the parting surface of cavity exhaust, also can be in the end of the pouring system of material flow set exhaust slot location, and leave gaps around the ejector rod achieve the goal of exhaust. Because of the depth, width, and location of the exhaust groove; If not properly, the resulting spines will affect the aesthetics and accuracy of the products. Therefore, the size of the above clearance is to prevent the appearance of the flying side near the top of the rod. It should be noted that in the exhaust of the gear such as gears, it may not be possible to have even the smallest edge
The exhaust of plastic mould should be noted Don't be too stressed out Don't overheat the plastic Don't inject too quickly Don't give the piston back too early The weight of the plastic parts should be near the device's rating
The effect of the exhaust tank The exhaust tank has two main functions. One is to exclude the air in the cavity when the fuse is fused. The second is to eliminate all kinds of gases produced during heating. The more thin wall products, the more distant the part of the gate, the opening of the exhaust slot is especially important. For small pieces or precision parts also should attach great importance to the opening of the exhaust slot, because in addition to it can avoid products surface burns and injection quantity is insufficient, also can eliminate the various defects of the products, reduce the pollution of the mould and so on. So how does the exhaust of the cavity be sufficient? In general, if the injection rate is injected at the highest injection rate, it is not left in the product, and it is considered sufficient to exhaust the cavity in the cavity
Open vent, Injection mold opening the exhaust is used in order to avoid excessive due to the cavity pressure during injection and cause chat cannot fill mold cavity, makes the quality of the product is unqualified, general is in the parting surface out enough clearance, but the gap is smaller than the injection plastic material overflow value. It is the deep drawing depth that is to be opened in the stamping die, in order to make a piece from the convex model the need to make a hole in the deep direction of the convex mode, and then the hole is in. Insufficient filling is often found in injection molding production. Compressed air burns, high internal stresses, surface flow lines and fuse lines. In addition to adjusting the injection molding process first, it is also necessary to consider whether the mould gate is reasonable. When injection molding process and water sprue are excluded; The exhaust of the mold is the main problem, and the main method of solving the problem is to open the vent.
