Design of Release Angle and Shear Edge for SMC Mould Demoulding

info@waiwaitree.com
+86-15382332967

Design of slope angle for SMC molded products during demolding

Due to the shrinkage of SMC products after cooling, the protrusions in the SMC molds core and cavity will tightly wrap the product. In order to facilitate smooth product removal and prevent the product from being bumped or scraped during demolding, the inner and outer surfaces of the SMC product should have sufficient demolding slope along the demolding direction.

When designing SMC molds, attention should be paid to the following two aspects

When molding large SMC products, the demolding slope of the inner surface should be larger than that of the outer surface;
The commonly used demolding slope is 1.1~1.5 degree, but it can also be as small as 0.5 degree.

Design of shearing edge for SMC mold

The shearing edge of the mold is the part where the upper and lower molds bite each other, and generally requires flame hardening. In the SMC mold pressing process, the shearing edge clamps the burr of the product. The burr is useless for the product, so the gap between the shearing edges can be larger. However, if the shearing edge is too large, it will cause runner and unloading pressure, which can be solved by adjusting the height of the shearing edge. The gap between the shearing edge and the height of the shearing edge are two factors that need to be designed and adjusted when designing the shearing edge. The size of the shearing edge is one of the most important factors in mold design. Whether the size of the shearing edge is appropriate directly affects whether the product can be formed and whether there are defects in the product formation. Therefore, it should be strictly required and controlled.

Design requirements for ejecting rod during separation of SMC mold

The design requirements of the ejecting rod for SMC molds indicate that the minimum diameter of the ejecting rod is allowed to reach 6mm, and the length-to-diameter ratio of the rod does not exceed 10:1. The ejecting rod on the curved surface must be locked to prevent rotation and provide unidirectional assembly control. The ejecting rod should be equipped with an ejecting rod sleeve, and its matching area should be larger than 15mm. The clearance between the ejecting rod and the ejecting rod sleeve is 0.05~0.07mm. The ejecting rod sleeve must be firm and welding structure must not be used. All ejecting rods and ejecting rod sleeves should be numbered, and their mutual position should be marked inside the mold with similar numbers. The end of the ejecting rod and the ejecting rod sleeve must have a 60-degree chamfer.

The high composite precision molds produced by AOBANG have the characteristics of low energy consumption; our SMC and BMC molds have no waste and no need to clean the cavity. With only a small temperature difference, our SMC/BMC composite materials have stable mold temperatures, good appearance and high efficiency. Therefore, they are now widely used in new energy vehicles, high-speed railways and motors. Welcome to inquire!