Process characteristics For lining tee products, the following points should be emphatically considered: Structural design drawings 1 and 2 show two types of lining products. At present, only FEP resin is used in China. The extruded E1 resin has good processing fluidity and a melt index of 4-12.
The lining product mainly adopts M3 type that is molding resin, and its melt index is 0. After a few days, cracking and other phenomena gradually appeared, so it cannot be used. Picture 1 Picture 2 Selection of resin materials Generally speaking, melt-processable fluoroplastics (FEP, PFA, PVDF, ETFE, PTFE) are suitable for molding lining products. On the other hand, the product configuration, especially the internal organ configuration, should be adapted to the molding pressure injection molding.
Therefore, the designer of the mold structure can choose arbitrarily. In comparison, the former has a slightly more complicated mold structure and more troublesome operations such as assembly and disassembly, but the product integrity is slightly better.. The difference is only with no pouring port (Figure i) and with pouring port (Figure 2). On the one hand, the product must have good versatility, BBQ grill mat that is, the relevant structural dimensions and installation dimensions should be as consistent as possible with the relevant standards in the valve.
The research and investigation of the products of these two structures shows that there is no difference in corrosion resistance and pressure (16MPa).8-2. For smaller village parts, extruded E2 type can also be used, with a melt index of 2 to 4. In some advanced industrial countries, lining parts of these different materials have been developed. It is prone to product cracking (discovered when the mold is removed) or in the molding process.The design of the lining product is the basis for designing the mold.
The latter has simple mold structure and process operation, but the integrity of the lining product is not as good as the former. According to GB9351, FEP resin is used for molding and extrusion. They complement each other and form a lineup of lining fluorine products with extremely wide adaptability.
However, due to its relatively low molecular weight, the product has poor resistance to stress cracking. These products have their own advantages in terms of physical and chemical properties, price and cost, processing adaptability and working condition adaptability