What is the difference between a bakelite machine and a regular injection molding machine?
Raw materials for the production of PF are mainly phenol and aldehyde. The most commonly used are phenol and formaldehyde, which are synthesized by condensation polymerization under the catalysis of acids and bases. There are two main types of industrial production, dry and wet.
Under the action of different catalysts, phenol and aldehyde can produce two types of PF: thermoplastic PF and thermosetting PF. The first type needs to add individual curing agent and in case of heating ability, the solidification becomes the body shape structure, the second type does not need curing agent, just want to be heated can only become the body shape structure.
Thermoplastic and thermosetting PF can only be used if the switching network has a solid shape. The solidification process is the continuation of the polycondensation reaction of the body and the final body product. This process is different from the melting and curing of thermoplastics in general. It is irreversible and involves both physical and chemical processes. PF can be molded using the same injection molding method as thermoplastics. PF for injection molding requires good fluidity, can be molded under low injection pressure, high thermal hardness and fast curing speed, surface of plastic parts has good gloss, convenient dismantling and non-contamination. mold dirty. However, injection molding also has its disadvantages, such as the melting is limited by the filler type, cannot insert more plastic parts into the mold, after processing a large number of gates, the runner cannot be recycled, can only be discarded.
Simply put, PF thermoplastics can be produced using conventional injection molding machines, but the process conditions must be carefully controlled. Thermosetting PF must be produced using a special PF injection molding machine (the barrel and screw are different from the ordinary injection molding machine), and the mold must be specially designed!
The screw barrel of the Minhui Bakelite Injection Molding Machine is special. The barrel does not need to be completely heated. It is usually heated by an oil temperature gauge (more precisely, a tank temperature control). The tank is provided with an insulation for hot oil circulation. Generally, the temperature is controlled between 70~110. Excessive heat will lead to hardening of the bakinglite powder.
II The action is equipped with an escape function. Close the glue injection mold open the exhaust mold (open 1 ~ 5mm) easy to close the mold difficult to flip the mold cooling material open the circulation
III The mold must be heated. Bakelite powder is a thermosetting plastic. Generally speaking, the movable mold is 10-25 degrees lower than the fixed mold. The dynamic matrix is set between 180 and 210 and some may have higher temperatures.
IV To enhance product quality control, the recycling value of Bakelite products is negative, meaning that if your unqualified products are recycled, you also need to pay someone else to dispose of them. waste
V Be careful not to heat your screw with the heating ring. If unfortunately, the high temperature will be difficult to cure. If you do not do well, you have to replace the whole set
Most injection molding is done using thermoplastics (melt, mold, then elastomer) such as nylon, polyethylene, or polystyrene. Both the machine and the mold must be able to dissipate heat (usually through water lines) that escapes as the plastic cools. Bakelite is a thermoset (goes into a liquid, polymerizes into a solid), much like epoxy or polyester. In many cases, it is desirable to be able to heat the mold to speed up the process. If the required temperature is below 100 degrees Celsius, the molding machine will normally work, except that it is connected to hot water instead of cold water. If higher temperature is required, another heating medium will be needed. Click here https://minhuiglobal.com/product/bakelite-injection-molding-machine to know more details.
