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Too fine particles are prone to contamination and ‘bridge’ phenomenon

Too fine particles are prone to contamination and ‘bridge’ phenomenon. 3, the shrinkage rate is small, the shrinkage rate is too large, the product is prone to cracks or warpage. The plasticized molten material can be stored in the barrel for a long time, and the waste-free injection molding process can avoid waste. The thermosetting plastic has good thermal stability at 70-100 ° C.. Second, molding equipment: Thermoset plastic no-channel injection molding equipment and thermoplastic injection molding machine are similar, the main differences are as follows: 1, injection device: compared with the molded thermoplastic, the screw length to diameter ratio is slightly smaller, about 14-18 The compression ratio is about 0.8-1. If the curing speed is too slow, the molding cycle is too long, the injection molded article is easily deformed and the size is unstable; if the curing speed is too fast, there may be insufficient filling or the surface of the plastic part is loose, so that the plastic part becomes waste, and the fast curing material can be used at this time. The temperature of the melt passing through the nozzle is about 110-140 ° C. The particles are too thick to make the surface of the product dull and the appearance quality is poor.

In order to meet the molding process requirements and keep the material temperature constant, a water heating system controlled by a constant temperature is generally used. 2, mold clamping device: thermosetting plastic mold clamping device is generally liquid-filled or voltage-regulated, can be exhausted. Since the molding temperature of the thermosetting plastic is very strict, and the barrel needs to be rapidly cooled in the event of an emergency, a cooling water jacket is also provided on the barrel. Thermoplastic plastics for injection molding that are too fluid may cause difficulty in injection molding and fill dissatisfaction. Perform high speed filling curing.2; the screw head is tapered to match the contour of the barrel and the nozzle, and the front end of the screw is not provided with a check ring to prevent the melt from flowing back; the nozzle is straight-through, the aperture is 2-3 mm; The nozzle must be provided with a heating setting, the mold temperature is high during the holding phase, and the nozzle must leave the mold to avoid the so-called casting phenomenon.No-flow injection molding materials and molding equipment

First, the material: Thermosetting plastic for flow-free injection molding must have the following molding process characteristics: 1, better fluidity, can fill various parts of the mold cavity under a certain temperature and injection pressure. If the fluidity is too large, there will be a ‘flash’ and a sticking phenomenon. At the same time, the thermosetting plastic Plastic mould manufacturers for injection molding should have a moderate particle size and uniformity. 4, the melt viscosity is lower than the general injection plastic, and the plasticization temperature of the thermosetting plastic for injection molding is generally 70-90 ° C. 2, the curing speed is high at high temperature. Thermosetting plastics have the lowest viscosity at temperatures ranging from 95 to 120 ° C, and plastics have better flow properties at this time

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