Basic knowledge of die-casting molds: structural composition and analysis of core component functions

As an indispensable process equipment in die-casting production, die-casting molds play a decisive role in the smooth progress of production and the quality of castings. Die casting technology refers to the process of rapidly filling the mold cavity with high-temperature molten metal under high-speed and high-pressure conditions, and rapidly cooling and forming it under pressure. The production process and operation of molds and die-casting are interdependent and mutually restrictive, with a very close relationship.

The basic structure of molds is mainly divided into two parts: fixed molds and moving molds. The fixed mold is the main component of the die-casting mold, connected to the injection part of the die-casting machine, fixed at the injection part of the press, and connected to the pouring system. It is an important part of the die-casting cavity. The fixed mold is mainly composed of fixed mold inserts, fixed mold sleeve plates, guide columns, wedge blocks, inclined guide columns, sprue sleeves, and fixed mold core pulling mechanisms. The dynamic mold is another integral part of the die-casting mold formed by the fixed mold, usually fixed on the middle plate of the die-casting machine, and moves open and close with the middle plate. It generally includes a core pulling mechanism and an ejection mechanism.

The core pulling mechanism is a key functional component in die-casting molds, used to move the movable core of molded parts that are not aligned with the mold opening direction. It is mainly composed of inclined guide columns, side cores, sliders, guide grooves, limit blocks, screws, springs, nuts, screws, etc. Among them, the inclined pin (inclined guide column) forces the slider to move during the mold opening process to extract the core, and its cross-sectional shape is often flat circular to prevent the slider from being pulled during core extraction. The angle α of the diagonal pin is related to the core pulling force, the length of the core pulling stroke, and the bending force it can withstand. It is usually taken as 10 °, 15 ° -18 °, 20 °, or 25 °.