Regarding the ejection system of the injection mold, the role of the ejector pin is understandable, so people pay much attention to the ejector, and the imprints on the ejector products are mainly reflected in two aspects.
(一)The irrationality of product design
The meat thickness of the product is an important factor to be considered in the structural design. Increasing the meat thickness can not only improve the filling properties of the resin but also reduce the orientation stress and reduce the deformation; on the contrary, too thin meat thickness will lead to difficulties in the plastic filling, which in turn makes the molding process difficult. The parameter of the item increases accordingly, which makes it easy to produce thimble imprints.
(二)mold design
The unreasonable design of the gating system: the flow channel is too narrow, the main flow channel is too long, or the sharp turning of the flow channel will increase the flow resistance, thus greatly limiting the flow filling of the plastic, which in turn affects the adjustment of the molding parameters.
The irrationality of gate design: form, location, size, the quantity of gate size. A gate that is too small will cause too much flow resistance, resulting in orientation stress. The internal stress near the gate is also the most serious area of stress.
Unreasonable design of ejector parts: the influence of the type, arrangement, size, position, and quantity of ejector parts, such as reinforcing ribs, flanges, inclined surfaces of plastic parts, etc.
The unreasonable design of the mold water system: the cooling of the product in the cavity is not uniform.
The unreasonable design of the mold exhaust system: when the product is in a vacuum state in the cavity.