Shanghai Daoqin Plastics Co., Ltd.

         material and screw formed pressure system. and screw 一样, material is in high pressure, high temperature, heavy abrasion loss, 一定 腐蚀 conditions lower as. in extrusion process in, material also has will hot amount to material material or will hot amount from material material in function. material upper also need add hot cooling system, machine 头. in addition, material upper need add material 口. add material 口 几何形状 and its 位置 选定 for add material property can effect/influence very large. material inner surface light degree, add material inner 壁开设沟槽 and other, for extrusion process has very large effect/influence, design or selection material 筒时都 need to upper factors.

        一, material structure

        就 material overall structure separation, has overall material and combined material 筒.

        （一）, overall material 筒

         is in overall material upper processing 出. this type of structure easy ensure relatively high manufacturing degree and assembly degree, can assembly as, add hot cooling system and 装拆, but also hot amount toward distribution comparison uniform, this type of material requirements relatively high processing manufacturing conditions.

        （二）, combined material 筒

         is 指一根 material is several material 筒段组 combined 起. property extrusion machine and gas extrusion machine more use combined material 筒. front is is 便于改变 material long degree 适应不 toward long ratio screw, rear is is 设置排 gas 段. in 一定意义 upper 说, using/adopting combined material has 利于就 取材 and processing, for in small type is has 利. 但实际 upper combined material for processing degree requirements very high. combined material material more use method 兰螺栓联接 in 一起. this 样就破 bad material add hot uniform property, increase hot loss 失. 也不便于 add hot cooling system and repair.

        （三） di metal material 筒

         is can meet/satisfy material for requirements, also can 节省贵 heavy material, less material in generally carbon or 铸钢 基体 internal alloy sleeve/set. sleeve/set abrasion loss rear can add more 换, sleeve/set and material need combined good, need ensure material upper hot 传导不受 effect/influence; material and sleeve/set 间既不 can has versus for 运动, also need can 方便 拆出, this need selection combined 适 配 combined degree, has factory using/adopting combined.

        （四）IKV material 筒

        1, material add material inner 壁开设纵 toward 沟槽

         is improve/increase solid 体输送 rate, solid 体输送理论知, types methods is increase material surface friction coefficient, also has types methods is increase add material material material through 垂直于 screw 轴线 横截面 面积. in material add material inner 壁开设纵 toward and will add material 段靠近 add material 口处 一段 material inner formed 锥形就 is this types methods specific 化.

        据 has material introduction, in material add material 段处开纵 toward or processing degree specific structure lower:

         generally lower, degree long degree can 取(3～5)D(D is material inner 径), processing powder material 时, degree can add long to (6—10)D. degree large small 决定于 material material pellets and screw 直径. screw increase 时, degree need decrease/reduce (meanwhile add material long degree need versus increase).

        纵 toward can in material material still is solid or 开始熔 melt front that material upper 开. long 约(3—5)D, has degree.

        沟槽 数目 and screw has 关, 据IKV introduction, versus screw 直径(cm) separation left right, 槽数太 more, 会导致 material material 回流, make amount decline. 槽 形状 can is long 方形, 三角形, or its it 形状. 横截面 is long 方形 沟槽 wide degree and deep degree and screw has 关, specific value can table/sheet 3-7.

        2, strong/high made cooling add material material 筒

         is improve/increase solid 体输送 amount, also has types methods. is cooling add material material 筒, is make by material material temperature degree maintain in soft or melting point below/following, 避免熔 film 出现, maintain material material solid scratch property 质.

         using/adopting upper methods rear, efficiency 由0.3 improve/increase to 0.6. but also extrusion amount for machine pressure 变化 敏感 property relatively small.

        但 this type of system has lower disadvantages: strong/high force cooling formed significantly can amount loss 失; due to in material add material 段末处 can can generate high pressure (has high 达800—1500公斤/ cm 2), has loss bad belt/tape has thin material 筒 危险; screw abrasion loss relatively large; extrusion property can for raw materials property relatively large. in addition, in small type extrusion machine upper using/adopting structure to made.

        （五） add material 口 形状 and 位置

         add material 口 形状 and its in material upper 开设位置 for add material property can has very large effect/influence. add material can make material material high add material 筒而不 generate 架桥, design also 应当考虑 to add material is 否适于设置 add material plant/unit, is has 利于清理, is 否便于 in 此段设置 cooling system. add material 口 形状(俯视) has 圆, 方, has 矩形. generally lower more use 矩形, its long 边平行于 material 筒轴线, long degree is screw 直径1.5—2倍.

        二, material material and strong/high degree 计算

        （一）, material material

         positive screw 一样, is meet/satisfy material 筒 工 as requirements, must excellent high temperature resistance, wear resistant loss, corrosion resistant, high strength material formed. this material also tool has good machine processing properties and hot property can. material remove can use 45号钢, 40Cr, 38CrMoAL outer, also can use and 球墨铸 iron manufacturing. belt/tape sleeve/set add material can use excellent iron made formed.

         in recent years. high speed extrusion and engineering plastics development, especially is extrusion glass fiber reinforcement plastics and has machine filler plastics 时, for material wear resistant corrosion resistant can force more high requirements. 由美, ratio and other development Xaloy alloy is types new wear resistant loss, corrosion resistant material, currently in outer to application. this type of material melting point low, hard, and has very good property, machine processing properties good, property can good, 且无浇铸应 force, rear make to bending, 也不会 formed sheet/slice 状脱落.

         will it application to material upper is using/adopting this 样 办 method: in high temperature lower will this type of powder Xaloy alloy and material 筒一起 add hot, due to its melting point low, large in 1200℃时即 can melt formed flow 状态, this make material high speed 旋转, melt Xaloy generate large force make 之浇铸 in hot material inner upper, its thick degree is 2 mm, cooling rear use abrasion methods abrasion 约0.20 mm, can meet/satisfy generally material requirements.

        据报导, ratio production types Xaloy alloy, hardness value can 达Rc58—64, in 482℃时, hardness obvious decline, corrosion resistant can force ratio nitrogen large 12倍.

        （二）, material thick and strong/high degree 计算:

        1, material thick 决定

         material very less strong/high degree 不足报 waste, main/primary is due to abrasion loss. material thick 决定, remove strong/high degree outer, more more is material structure process property and hot property. according to rear factors 决定 壁 thick large strong/high degree conditions 计算出 value. due to formed according to material hot features material thick methods, therefore currently large more according to experience statistics type ratio 决定壁 thick, again strong/high degree 校核

        2, strong/high degree 计算

         material strong/high degree 计算按 thick 壁筒进行. 此处不 again 进行讨论

         attention/notes: material is property material 时, can use strong/high degree 理论进行计算.

        当 material is property material use strong/high degree 理论进行计算.

        当 material inner has sleeve/set 时, versus 当于“ machine parts ” in combined in pressure combined 连接, this sleeve/set and material 筒 应 force 状态都 comparison complex, its strong/high degree 计算也 comparison complex.