Wuhan Handern Transfer Molding
日期：2021/1/14 9:19:22 / 閱讀： / 來源：本站
Wuhan Hyundai Transfer MoldingThe main molding method of thermosetting plastics is compression molding, but this method has a series of shortcomings. For example, when the production cycle is long, the dimensional accuracy of parts is not as good as that of thermoplastic injection molded parts: at the same time, it is not suitable for the production of fine inserts, Medical parts with complex structure. In order to overcome the above shortcomings, referring to the experience of thermoplastic injection molding, transfer molding and injection molding of thermoset plastics have appeared. PVDF photovoltaic film production line www.www.dressup9x.com
The characteristic of transfer regulation is that the plastic adopts lower pressure flow to close the cavity in the plastic state. Therefore, transfer correction has the following advantages: ①The flash at the parting surface is thin and easy to repair; ②The material can heat through and harden quickly and uniformly in the mold. When the wall thicknesses of the plastic parts are the same, the co-hardening time is only equivalent to 1/3-1/5 of the compression molding, so the molding cycle is short: ③It can mold thin, high, and large parts. Parts: ④The molded parts have high dimensional accuracy; ⑤The mold wears little and has a long service life. The disadvantages are: ①Transfer molding consumes more materials than compression molds, because there will be a small amount of residual material in the cavity after die casting; ②The structure of the compression mold is more complicated than that of compression molding, so the cost is higher; ③Pressure The loss is large, so high molding pressure is required.
The requirements of transfer molding for formability are: before reaching the hardening temperature, the plastic should have greater fluidity, and after reaching the physical and chemical temperature, it must have a faster hardening. Can meet this requirement are grading aldehyde, melamine formaldehyde, urea formaldehyde, epoxy resin, unsaturated polycarbonate, polydiformic acid two-field acetonitrile thermosetting plastic.
Your hand-in-hand craftsmanship is based on the injection molding of thermophilic plastics. The difference is that the plastic is heated and melted in the cavity of the mold instead of being plasticized in the material of the injection machine.
The leader of the chemical delivery gauge adds the heat-trapped type Kegian pre-pressing tablet to the material cavity on the combined pressure electrode, so that the co-heating and softening, and under the pressure of the pressure column matched with the material cavity , Make the married plastic flow into the cavity through the sprue at the bottom of the material cavity and the runner and gate of the mold. The chemical reaction surface is finished during the shaping, and the part is obtained after demolding. PVDF photovoltaic film production line www.www.dressup9x.com
The transfer molding press is a compression molding press. The difference is that it is also equipped with an auxiliary hydraulic system. The auxiliary plunger can be installed above or below the press or on the side. The mold closing direction is vertical. The function of the auxiliary hydraulic system is to die-cast the material in the feeding chamber (material cavity) into the mold cavity through the plunger.
The equipment used for transfer molding is mainly a press and a die. The pressing machines and operating methods can be divided into the following categories. 1. Compression molds for ordinary presses
The connection form of the pressing die and the press can be divided into a mobile pressing die and a fixed pressing die.
(1) Movable die is also called cavity die, as shown in Figure 7-14. A feeding cavity is installed on the mold. After the mold is closed, a quantitative material is put into the cavity, and the press is closed to make the pressure column squeeze the plasticized material into the cavity at high speed. After the hardening is finalized, it can be used manually Take out the plastic part.
(2) The fixed pressure mold is fixed on the upper and lower table of the press, and the mold is divided into three parts when the mold is opened
The pressure column is fixed on the upper table of the press. PVDF photovoltaic film production line www.www.dressup9x.com
The material cavity is fixed on the movable rice. When starting the pole, it separates from the parting surface and becomes a floating state.
The cavity is fixed on the lower table of the press and the lower table of the press is opened and lowered. The molds when the press descends and rises