Push block the top of the push block at the top of the transparent material commonly used products, product surface is not allowed without the use of the push plate signs thimble way ejection. Figure 2-57 shows the block to push the top of the structure diagram pvc, can be learned from the figure, the push block connected together by a screw thimble, push the block to be done outside of the slope. In the top of the push block design takes note of the following points: the push block with high hardness and a smaller surface roughness, and to ensure there is enough strength to push the block, while ensuring low friction during movement of the exhaust trough section size, attention, different plastic materials stocks vent groove depth dimension in the mold, depending on the depth dimension of the resin dry and is easy decomposition. Easy decomposition of resin, its exhaust groove area can be larger; low degree of dry material, its exhaust groove depth to be shallower. Table 2-1 lists the exhaust slot size used plastic limb material, the use of exhaust thimble and needle inserts for larger depth dimension ribs, in the injection molding process is often filled with difficulties arise, lack of glue, trapped gas and other phenomena, You can now add a thimble, thimble use gap between the exhaust pvc drainage pipes, such as the exhaust thimble may be used in addition to, but also can be split into core or cavity inserts needles assembled in the mold, to take advantage of the gap exhaust. Positioning mechanism utilizing steel exhaust ventilation, with all the parts are required to locate, the purpose is to locate the part fixed in the specified location, to prevent its movement, this section describes several mold positioning structure. Formwork fine positioning mechanism design, mold fine positioning means mold clamping process can move 7 set to the desired mode to pinpoint positions to avoid a collision between the two. Use the slope boss locators (in-mold tube bits), many mold factory will process slope boss pvc pinch on movable core and cavity 丨 given model to take advantage of the boss pinpoint pvc fence, Figure 2 - 69 for the structure shown schematically. Tips from the pipe-bit block tube position between the block and the template to be installed around the middle of the plate in Mozambique, and positioning, guide balance. Rectangular pipe-bit block diagram above has two parts, but a lot of mold factory in order to reduce the cost of mold will preclude the use of a pipe-bit parts, as shown in Figure 2-74. As it can be understood from the figure, scheduled to die in the tube positioning device is working directly on the template set out, thus saving a part. pvc plastic plate, Luohu pvc, Gary Paffett trade is supplied by Shenzhen Trading Co. Gary Trade Co., Ltd. of Shenzhen City (www.pft-trading.com) strong, credible, Shenzhen in Guangdong's plastics industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead Parfitt trade into the brilliant and you work for a better future!