1. Applicability of BMC mold
BMC molds are bulk molding compounds, which are often referred to as unsaturated polyester bulk molding compounds in China. The main raw material is a dough-like prepreg which is fully mixed by GF (chopped glass fiber), UP (unsaturated resin), MD (filler) and various additives. BMC molds were first used in the former West Germany and the United Kingdom in the 1960s, and then developed in the United States and Japan in the 1970s and 1980s, respectively. Because BMC bulk molding compound has excellent electrical properties, mechanical properties, heat resistance, chemical corrosion resistance, and adapts to various molding processes, it can meet the performance requirements of various products, so it is more and more popular among users. favorite.
A BMC mold is a thermoset plastic in which various inert fillers, fiber reinforcements, catalysts, stabilizers and pigments are mixed to form an adhesive "putty-like" composite for compression or injection molding. BMC molds are highly filled and reinforced with short fibers, 10% to 30% glass fiber reinforcement, and are typically between 1/32 inch and 1/2 inch in length.
2. The advantages of BMC injection mold
BMC is the abbreviation of glass fiber reinforced unsaturated polyester thermosetting plastics, which is the most widely used type of reinforced thermosetting plastics. The advantages of BMC injection mold are mainly reflected in the following points:
(1) Features of BMC injection mold
BMC has good physical properties, electrical properties and mechanical properties, so it has a wide range of applications, such as making mechanical parts such as gearbox components, intake pipes, valve covers, bumpers, etc.; Durable aviation, construction, furniture, etc. are also widely used; in its traditional electrical field, its use is also more and more extensive.
(2) Application of BMC injection mold
BMC injection molding machine In BMC, due to the addition of glass fiber, the equipment used is somewhat different from the usual thermosetting plastic injection molding equipment. The injection molding machine used can be either plunger type or screw type.
Feeding system. Whether it is a screw type or a plunger type, an extrusion feeding device must be attached to force the material into the barrel. Because the injection volume of the plunger injection molding machine is accurate and constant, the glass fiber is dispersed in the melt with less damage. Therefore, the plunger injection molding machine is used more, but the exhaust is inconvenient; heating system. In BMC injection mold molding, it is very important to control the temperature of the barrel. There must be a control system to control the temperature to ensure that the temperature from the feeding section to the nozzle is optimal. At present, constant temperature water or constant temperature oil is mostly used for heating. Electric heating can also be used.