the placement of the gate is one of the important parts of the mold design. The design of the die-casting die gate is almost all from the filling, forming quality and flow state of the casting, and it seldom takes into account the effect on the subsequent machining.

    from any point of view, the placement of the inner gate of the die casting is the key and difficulty in the design of the casting system, and any negligence will cause an unpredictable error. At the same time, this error can not be made up by the adjustment of the die-casting process; from the point of view of the die casting production, the gate is selected. The following basic principles are followed:

    (1) avoid the liquid metal entering the cavity immediately after sealing the exhaust slot, which is conducive to exclude the gas in the cavity.

    (2) to minimize the use of branch gates, so as to avoid the interference of multiple metal streams, forming eddy currents and wrapping gas.

    (3) the gate face is not directly opposite to the core and cavity wall, so as to avoid direct impact of molten metal.

    (4) inner gate should be placed in the thicker part of the casting to facilitate pressure transfer.

    (5) the metal liquid flow is the shortest to reduce energy loss and avoid too much cooling.

    (6) inner gate should not cause deformation during casting shrinkage.

    (7) as far as possible, the runner shall be placed near the important part of the workpiece.

    in the design of die casting mould, if the following mechanical processing is not taken into consideration, the setting of the gate position can satisfy these conditions, then it can be said that the placement of the gate is perfect; however, in the production, most of our die-casting parts need to be machined, if the desert is to be machined. Depending on the actual demand for casting blanks, mechanical processing will bring some unnecessary trouble to them. It is mainly manifested in the following aspects: the effect of residual removal after gate removal on machining positioning and intermittent machining of gate parts machined.