Shanghai Daoqin Plastics Co., Ltd.

gate design and parts dimensions, mold structure, injection process conditions and parts property can and other factors has 关. basic function 说, gate need small, long degree need short,因 is has this can meet/satisfy increase large material speed degree, fast speed cooling 封闭,便于塑 parts separation and gate most small and other requirements.

一, gate need meet/satisfy requirements

1. appearance requirements (gate 痕迹, weld lines)

2. product function requirements

3. mold processing requirements

4. product warpage deformation

5. gate 容不容 easy remove

二, for production and function effect/influence

1, long injection shot pressure, clamping force, and product 填不填 满流 long shrink short can reduce injection shot pressure and clamping force.

2, gate 位置会 effect/influence holding pressure pressure, holding pressure pressure large small, holding pressure pressure is balanced, will gate product force 位置（如 bearings 处）以避免残留应 force, gate 位置必 must 考虑排 gas, 以避免积风发生, need will gate in product relatively low or 嵌入处, 以避免偏位.

三, selection gate tips/techniques

1, gate

gate is strip/profile 横切面面积 fine small short 槽, use 以连接 runner and 模穴. 横切面面积 therefore need small, is need obtain below/following 效果:

1）模穴注不久, gate cold 结

2） remove water easy

3） remove water 口完毕,仅留 lower less 许痕迹

4） make more filler relatively easy control

5） decrease/reduce filler more phenomenon

2, gate 位置以 and dimensions

1） will gate 放置于 product most thick 处, from most thick 处进浇 can provide relatively 佳 充填 and holding pressure 效果. if holding pressure 不足, relatively thin 区域会 comparison thick more fast solid, will gate in thick degree 突然变化处, 以避免迟滞 phenomenon or is short 射 发生.

2） can can 话, from product in 央进浇, will gate 放置于 product in can provide and other long long, long large small effect/influence injection shot pressure, in 央进浇 make direction holding pressure pressure uniform, can non-uniform shrinkage.

3）当 plastics runner 时, plastics 接近模面 most drop hot (cooling) and solid. plastics again toward front flow is in solid plastics 层流. also due to plastics is low hot material 质, solid plastics formed 绝绿层 and maintain still can flow. therefore, in 理想 情况 lower, gate 应设置 in runner 层位置, make most plastics flow 效应. 此情况 most Common 于圆形 and 六角形 横 runner. however 梯形 横 runner method 达致此效果,因 gate can 设置于 runner in 间位置.

决定 gate 位置时,应紧守 lower 列原则:

1, 注入模穴各部份 胶 material amount 平均.

2, 注入工模 胶 material, in material process stage/phase,都应 maintain 统一而 stability flow front 线.

3, 应考虑 can can 出现焊痕, bubbles,凹穴,虚位,射胶不足 and and other 情况.

4, amount make remove water as easy 进行, most good is 自动操 as.

5, gate 位置应 and 各方面配 combined.

design gate methods hard property 规定, large is according to experience 而行,但 has basic elements must add 以折衷考虑:

1） gate 横切面面积愈 large good,而槽道之 long degree short 愈佳,以 decrease/reduce plastics through pressure loss 失.

2） gate must fine narrow,以便容 easy cold and anti amount plastics 倒流.故此 gate in runner in 央,而 it 横切面应尽 can can formed 圆形. 不, gate usually is parts 开关 决定.

3, gate dimensions can 由横切面积 and gate long degree 定出, lower factors can gate most dimensions:

1）胶 material flow features

2）模 parts thick thin

3）注入 mold cavity material amount

4）熔 understanding temperature degree

5）工 mold temperature degree

四, gate balanced

if can obtain balanced runner system, can using/adopting lower gate balanced method, to 划一注模 target/goal. this type of methods suitable for has a large amount of 模穴 工模.

gate balanced method has types: gate long degree and gate 横切面面积. in types lower,即模穴 has different 投影面积时, gate need balanced.

this 时, need gate large small,就 need will its in gate dimensions 定出,求出 it and its for 应模穴体积 versus relatively ratio rate, and this ratio rate application to its gate and for 应模穴 comparison upper,便 can versus 继求出各 gate dimensions. 经 实际试注 rear,便 can formed gate balanced as.

五, gate or large water 口

浇道直接 supply plastics to made formed product, 浇道黏附 in made formed product upper. in sheet/plate 工模, large water usually is 一出一隻, in sheet/plate or hot runner design upper, can more 隻.

disadvantages: in made formed product surface formed water 口印会 effect/influence formed product appearance, water large small in 于唧咀 fine 直径孔.

六, demolding 角, long degree

therefore large water can decrease fine, need will upper 述唧咀 dimensions small.但唧咀 直径受唧咀直径 effect/influence, water need easy 于出模 关系, demolding can less 3 degree, therefore has long degree can decrease short, use add long 唧咀即 can.