The operation procedure of the precision casting process of the bushing

The so-called precision casting process is simply to use fusible materials (such as wax or plastic) to make a fusible model (referred to as investment or model), apply several layers of special refractory coatings on it, and then dry and harden it. After forming an integral shell, use steam or hot water to melt the model from the shell, then put the shell in the sand box, fill the mold with dry sand around it, and finally put the mold in the roasting furnace through high temperature Roasting (if a high-strength mold is used, the mold shell after demolding can be directly fired without modeling). After the mold or mold is fired, molten metal is poured into it to obtain a precision casting.

    Precision casting process operation procedure:

    1. Take out the wax tank from the heat preservation tank and install it on the double-station hydraulic wax injection molding machine. The air and hard wax in the wax should be removed before use.

    2. Position the mold on the worktable of the injection molding machine, check whether all the cores of the mold are in the correct position, and whether the wax injection port of the mold is aligned with the injection nozzle of the injection molding machine.

    3. Check whether the mold opens and closes smoothly.

    4. Open the mold and spray a thin layer of parting agent.

    5. Adjust the time cycle of the injection machine in accordance with the technical regulations, including injection pressure, injection temperature, pressure holding time, cooling time, etc.

    6. After each cycle, pull out the core, open the mold, carefully take out the wax mold, and put it in the cooling water or storage tray as required. Note that wax models with the following defects should be scrapped:

    A The wax mold is partially bulged due to air entrapped in the mold material; B is missing corners in any part of the wax mold; C is deformed and cannot be easily repaired; D The size does not meet the requirements.

    7. Remove the remaining mold material on the mold. Note that only a bamboo knife can be used instead of a metal blade to remove the remaining mold material to prevent damage to the mold cavity and parting surface.

    8. Close the mold and press the wax mold next time. After each shift or after the mold is used, use a soft cloth or cotton swab to clean the mold, and fasten the mold with screws.