Before designing the parting surface, it is necessary to determine the shape and position of the parting line on the plastic part. When the opening direction is determined, it is easier to determine the parting line, because the projection of the parting line in the opening direction and the projection of the part in this direction The outer contours coincide, so a line parallel to the opening direction can be moved along the opening direction. The outer contour of the object projection. At the same time, find the intersection of the line with the surface of the object at each position.

(1) The point where the straight line intersects the surface of the object is the point on the parting line.

(2) Intersecting the object at multiple points and multiple segments indicates that the intersection of the global approximation cone and the mold opening direction is zero. Therefore, the core-pulling should be determined according to the shape and size of the core-pulling in the area design. (2) When the straight line intersects the object, the shape and size of the drawing core should be considered.

(3) The straight line in the straight line segment intersects the object surface, then any point on the straight line segment can be used as a point on the segmentation mode line. It is specifically determined which point is the point on the segmentation line, generally based on the straight line and the adjacent point The straight line between is the shortest principle, and the principle of mutual determination can also be used to determine which point on the dividing line is the point on the dividing line, that is, the point on the dividing line is the point on the dividing line.