1 Open-type filling die Open-type filling die is characterized by no direct positioning between the upper and lower stencils. If positioning is required, positioning of the mutual position is achieved by positioning mechanisms such as locating pins. The structure of the open filling die is only closed when the end faces of the upper and lower molds are completely closed. The cavity is always open during the entire closed mold stroke, so it is easy to discharge the gas in the cavity, but the rubber loss is more, generally 10%~15%. The smaller the product, the larger the amount of lost glue, thus causing the lack of glue. And the possibility of producing waste is also great. In addition, the biggest disadvantage is that the rubber is not subjected to pressure and compactness during pressing, and the physical and mechanical properties of the product are not high.
2 The closed filling die is characterized in that the upper and lower templates are directly guided and positioned in the extended portion of the mold cavity. The upper mold has a convex portion extending into the continuation portion of the cavity. After the point A of the convex portion of the upper mold is in contact with the point B at the upper end of the continuation portion, the cavity is closed, so it is called closed type. The advantage of this mold structure is that the pressure of the press is almost always applied to the rubber, so the quality of the product is good, and the rubber is difficult to flow out of the mold cavity: the phenomenon of partial underpressure and filling of the mold can be avoided, and the obtained product can be obtained. The density of the parts is very high. However, this mold structure has the disadvantage of poor exhaust performance. In addition, from the mold manufacturing, the mold structure is more precise than the open filling mold, and the edge of the upper and lower stencils is prone to wear during use.
In the molding production, such molds require that the mold compound must be weighed strictly, and each press must be made into a quantitative mold to ensure the quality of the product parts.
What are the structural forms of the pressure-filled molding die?
2019年3月2日
Rubber Molds FAQs
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1 Open-type filling die Open-type filling die is characterized by no direct positioning between the upper and lower stencils. If positioning is required, positioning of the mutual position is achieved by positioning mechanisms such as locating pins. The structure of the open filling die is only closed when the end faces of the upper and lower molds are completely closed. The cavity is always open during the entire closed mold stroke, so it is easy to discharge the gas in the cavity, but the rubber loss is more, generally 10%~15%. The smaller the product, the larger the amount of lost glue, thus causing the lack of glue. And the possibility of producing waste is also great. In addition, the biggest disadvantage is that the rubber is not subjected to pressure and compactness during pressing, and the physical and mechanical properties of the product are not high.
2 The closed filling die is characterized in that the upper and lower templates are directly guided and positioned in the extended portion of the mold cavity. The upper mold has a convex portion extending into the continuation portion of the cavity. After the point A of the convex portion of the upper mold is in contact with the point B at the upper end of the continuation portion, the cavity is closed, so it is called closed type. The advantage of this mold structure is that the pressure of the press is almost always applied to the rubber, so the quality of the product is good, and the rubber is difficult to flow out of the mold cavity: the phenomenon of partial underpressure and filling of the mold can be avoided, and the obtained product can be obtained. The density of the parts is very high. However, this mold structure has the disadvantage of poor exhaust performance. In addition, from the mold manufacturing, the mold structure is more precise than the open filling mold, and the edge of the upper and lower stencils is prone to wear during use.
In the molding production, such molds require that the mold compound must be weighed strictly, and each press must be made into a quantitative mold to ensure the quality of the product parts.