PTFE automatic molding process
1. After automatically adding a certain amount of PTFE resin powder with good flowability to the mold cavity by its own weight, lower the upper male mold into the mold sleeve to press the powder
2. Raise the upper male mold to do two-way compression of the powder, usually for a few seconds
3. After holding the pressure for a period of time, the upper mold is raised
4. The lower male mold ejects the product and becomes a mold release
Note:Because the entire cycle of automatic molding is short, usually only 10-15 seconds, and the holding time is only a few seconds. In order to ensure the elimination of voids, a higher pressure than the general molding pressure needs to be applied, generally reaching 40-60MPA. When the automatic compression molding is running, the temperature of the PTFE powder will increase due to friction and become softer and more viscous. As a result, the "bridging" phenomenon in the feeding area is likely to occur, resulting in uneven feeding in the feeding cavity and inconsistency in each feeding. Therefore, the temperature should be maintained at 23-25°C throughout the molding area.