Shanghai Daoqin Plastics Co., Ltd.

        越 is thin products, is gate 部位, gas 槽 开设就显 尤 is important. another, for/regarding small type parts or precision parts, need heavy gas 槽 开设, is it remove can products surface and injection amount outer, also can remove products various defect, decrease/reduce mold and other.

        排 gas function main/primary has 两点: is in injection melt material material 时, troubleshooting mold cavity inner gas;二 is troubleshooting material material in add hot process in generate various gas 体.

         that 么, mold cavity gas how to 才算充 separation 呢? generally 说, most high injection speed rate injection material, in products upper 却未留 lower 焦斑, can is mold cavity inner gas is separation.

        1, gas methods

         mold cavity gas methods very more, 但每一 types methods must ensure: gas in gas meanwhile, its dimensions design can anti material material 溢进槽 inner; its also need anti 止堵塞. therefore, from mold cavity inner surface toward mold cavity outer direction amount, long 6-12mm above gas separation, high degree need large 约0.25-0.4mm.

         another, gas amount more is has 害. is, if function in mold cavity separation type 面未开排 gas separation pressure very large, easy mold cavity material cold or 裂开, this is very 危险.

         remove in separation type upper for mold cavity gas outer, also can through in system material 流末端位置设排 gas 槽, and ejection 杆四周留出间隙 methods to gas 目, is gas deep degree, wide degree and selection, if 不适当, generate flash 毛刺, will effect/influence products and degree. therefore, upper 述间隙 large small anti ejection 杆四周出现 flash is 限.

         this especially attention/notes is: gears this made parts in gas 时, can can most micro small flash is 不希望 has, gears made parts most good using/adopting below/following methods gas:

        (1)彻底清 remove runner inner gas 体;

        (2) use degree is 200 carbon silicon abrasion material for separation type combined surface 进行喷丸处理.

         another, in system material 流末端开设排 gas 槽, main/primary is separation runner 末端位置 排 gas 槽, its wide degree and other separation runner wide degree, high degree material 而异.

        2, design methods

         for/regarding complex 几何形状 product mold, gas 槽 开设 most good in mold trial rear again 断定. mold structure design in overall structure 形式, its most large disadvantages is gas defect.

         for overall mold cavity 模芯, has below/following types gas methods:

        (1) utilizing type 腔 槽 or parts 安装部位;

        (2) utilizing 侧面 嵌 parts 接缝;

        (3) local made formed 螺旋形状;

        (4) in toward upper upper belt/tape sheet/plate strip/profile 心, process 孔.

        当排 gas difficult 时, using/adopting structure and other. if has mold 死角不 easy gas 槽, 首先应 in effect/influence product appearance and degree lower, mold is processing, this 样, not only has processing gas 槽, has also can improvement has processing difficult degree and repair.

        3, gas design dimensions

         hot solid property material gas ratio thermoplastic property material more is important.

        首先, in gate front separation runner 都应排 gas. gas wide degree and other separation runner wide degree, high degree is 0.12mm. mold cavity 四周都应排 gas, gas versus 隔25mm, wide degree is 6.5mm, high degree is 0.075-0.16mm, material material flow property 而定. relatively soft material relatively low value.

         ejection 杆应尽 amount large, but also in large more combined, ejection 杆圆柱面 upper abrasion 出3-4 high 0.05mm 平面, abrasion direction ejection long degree direction. abrasion application degree relatively fine 砂轮进行. ejection 杆端面应当 abrasion 出0.12mm 倒角, this 样, has flash formed 时, viscous in made parts upper.

        4, 结论

        适当 开设排 gas 槽, can large large reduce injection pressure, injection time, holding pressure time and pressure, make parts molding difficult is easy, from improve/increase production efficiency, reduce production cost, reduce machine can amount consumption.

         its 实, full must through gas 槽 排 gas. gas methods also has lower its it types methods:

        (1)排 gas gas

         for/regarding molding large, in type parts mold, troubleshooting gas amount more, usually 都应开设排 gas 槽, gas usually in separation type upper 凹模一边. gas 槽 位置以处于 melt flow is good, gas dimensions gas can 顺利 排出而不溢 material is 原则. gas wide degree generally is 3-5mm left right, deep degree small 于0.05mm, long degree generally 0.7-1.0mm.

        (2) separation type gas

         for/regarding small type mold, can utilizing separation type 面间隙排 gas, separation type must melt flow 未端.

        (3)拼镶 parts 缝隙排 gas

         for/regarding combined 式 凹模 or type 腔, can utilizing its combined 缝隙排 gas.

        (4)推杆间隙排 gas

         utilizing and sheet/plate or type 芯 配 combined 间隙排 gas, or has add and sheet/plate 间隙.

        (5) powder 未烧结 alloy block gas

         powder 未烧结 alloy is use pellets alloy 烧结而 formed material, strong/high degree relatively 差, hydrophobic 松, gas through. in gas 部位放置一 block this alloy can to gas requirements, its 底部通 gas 孔直径不宜太 large, anti type pressure will its pressure deformation.

        (6)排 gas gas

         in plastics melt combined outer 侧, 设置一 空穴, make gas 体排入 its in, can obtain good gas 效果.

        (7) strong/high made property gas

         in gas 体 部位, 设置排 gas 杆, method gas good, in parts upper lower parts 痕迹, gas 杆应设 in parts 隐蔽处.