Shanghai Daoqin Plastics Co., Ltd.

system control is ensure PVC type quality long stability key/critical, it 包含“ formulation quality, process quality, appearance quality, indicators ” and other 4 project, front is 後两项 front and 基础, is quality tube/pipe made and technology tube/pipe heavy in heavy. resin and additives mixed combined uniform degree and mixed combined material table/sheet density large small for PVC impact strong/high degree generate relatively large effect/influence. PVC processing temperature degree has scope/range, temperature degree high, PVC easy separation understanding; temperature degree low, PVC塑化不充 separation, various separation dispersion also 会导致脆 property increase large. machine speed extrusion machine for PVC function, speed large, force increase large, reduce products low temperature property can and strong/high degree. molding pressure high has improve/increase type force property can, especially is low temperature impact strong/high degree. type molding cooling function is will tensile large separation and cooling type, to products requirements. slow cooling can make large separation has time 舒展, this internal stress small, can decrease light products warpage, bending and shrinkage, from improve/increase products impact strong/high degree and welding bad force. formulation formulation can raw materials. formulation good bad 并不完 full 取决於组 separation ratio, in very large degree upper 取决於 raw materials inner in property can and quality. is composite/compounding stabilizer, internal separation different, is and other raw materials 不协调而 effect/influence type quality. therefore, formulation 时, is 确定 每一 types Raw Materials Model/Grade and injection molding processing processing 家之後, has 实际意义. in new 疆天业 building materials company, use PVC resin, CPE use 潍坊亚星 chemical corporation has company product, titanium powder use DuPont company （DuPont） product, therefore, 本文 讨论 composite/compounding stabilizer and increase amount agent. composite/compounding stabilizer is PVC processing in most important type additives, for PVC type has indicators generate effect/influence. composite/compounding stabilizer stability and lubricated types function. stability function is retardant 止PVC separation in processing and use process in degradation, from ensure PVC type can tool 备门窗 requirements force property can; inner outer lubricant effect/influence flow property and viscosity, effect/influence PVC type cold impact property, strong/high degree, dimensions rate, add hot 後状态 and surface light degree. currently, for Raw Materials comprehensive market market trends, reduce formulation cost is very more injection molding processing processing 家不约而同 selection, reduce formulation cost main/primary has 两 途径: use price relatively low raw materials, ratio use price relatively low stabilizer, modifier and other; use increase amount agent, commonly used is price relatively low carbon acid 钙. carbon acid remove increase amount reduce cost outer, also tool has stability dimensions function; carbon acid use amount add large, type inner in indicators obvious decline （见 table/sheet 1）. table/sheet 1CaCO3 use amount for type physical properties effect/influence. mixed material equipment mixed material is PVC type production in important ring. mixed material process not only is separation machine mixed combined, more is separation versus scratch, 碰撞, material material rise temperature, 逐步凝胶化 process, therefore dry mixed material quality effect/influence PVC type physical properties and chemical property can. outer expert is, good mixed material machine can 弥补塑化差 extrusion machine, make is most good extrusion machine can mixed material machine 不足, can mixed material machine important property. in mixed material machine inner, material material in short time inner 靠自摩 scratch normal temperature rise 至120℃, day month 累, for mixed material machine abrasion loss is very large. according to experience, in Raw Materials, formulation, equipment, process 不变 情况 lower, in long 6m type upper 取样, type cooling impact experiment/testing 结果却 versus very large: 8 Sample good loss, 1 Sample has small cracks, 1 Sample 出现破洞. 经 排查, is material material mixed combined non-uniform, use amount relatively small additives dispersion good formed local defect. more hot mixed 搅拌桨後, issues solution. mixed material machine abrasion loss performance is mixed material 时噪音 large, 刺耳, mixed material time long, generally 8-10min延 long 至15min above. long time comparison, to PVC pellets most large density and most large degree 凝胶化, hot mixed temperature degree control in 115℃ left right, mixed material time in 8-10min, add material amount is mixed material machine 容积 60% left right, this 样 效果 is relatively 理想. 冬季时, can will mixed material machine speed high 一; 夏季时, will mixed material machine speed low 一. through this adjustment, can ensure as efficiency, control good mixed material time. need to PVC material material quality, screw, machine processing degree and assembly degree is very important factors. high assembly degree combined optimization extrusion process, can relatively good ensure PVC type quality. therefore, need testing screw, machine 筒 轴 toward and toward 间隙, combined 规定时 need and adjustment. extrusion process Common issues degradation PVC is hot property plastics, light stabilization property very 差, in hot and light function lower, very easy 发生脱HCl reaction, usually degradation. degradation is plastics products strong/high degree decline, color, 出黑线, heavy 时导致 products use value. effect/influence PVC degradation factors has polymer structure, polymer quality, stability system, molding temperature degree and other 方面. according to experience, PVC type 材发黄 large more is is 口模处出现糊 material, its causes is runner combined or runner inner local light good, in material 区. 而PVC type 材出黄线 large more is machine inner 出现糊 material, its causes main/primary is sheet/plate （ or sleeve/set ） between has 死角, material material flow 不畅. in PVC type upper toward 直线, material is in export 处; 若黄线不直, main/primary is in sleeve/set. formulation and raw materials 不变时也出现黄线, main/primary from machine structure upper causes, to separation understanding 起始点并 add troubleshooting. from machine structure upper to causes, 则应考虑 is formulation or process 方面存 in issues. degradation measures has below/following several 方面: （1）严格 control Raw Materials technology indicators, need use combined raw materials; （2） made combined molding process conditions, in conditions lower PVC material material easy degradation; （3） molding equipment and injection molding processing mold structure good, need remove equipment and material material 接触面 can can in or 缝隙; runner is type, long short 适宜; improvement add hot plant/unit, improve/increase temperature degree plant/unit degree and cooling system efficiency. bending deformation PVC type bending deformation is extrusion process in Common issues, its causes has: 口模出 material non-uniform; cooling type 时, material material cooling separation, shrinkage amount 不一致; equipment and other factors. extrusion machine full 线 同心 degree and water degree is solution PVC type bending deformation front conditions, therefore, more injection molding processing mold 时都应 for extrusion machine, 口模, type 模, water tank and other degree and water degree 进行校 positive. its in, ensure 口模出 material uniform is solution PVC type bending key/critical, machine front true assembly 口模, 各部位间隙 need 一致, machine 时发现口模出 material 不均, based on type bending deformation direction, for adjustment mold temperature degree, adjustment 无效, 则应适当 improve/increase material material degree. 进行辅助 adjustment adjustment type true degree and cooling system is solution PVC type deformation necessary 手段, add large type 材承受 tensile force cooling water amount; using/adopting machine 械偏移 in methods adjustment, 即一边 production, adjustment type in 间 定位螺栓, based on type bending direction 进行反 toward micro amount adjustment （ using/adopting method 时应慎 heavy, adjustment amount large ）. heavy injection molding processing mold maintenance is very good anti measures, 应密切关注 injection molding processing mold as quality, according to 实际情况随时 for injection molding processing mold 进行维护 and maintenance. through above measures can remove type bending deformation, ensure extrusion machine stability, positive production high quality PVC type 材. low temperature impact strong/high degree effect/influence PVC type low temperature impact strong/high degree factors has formulation, type 材断面 structure, injection molding processing mold, degree, testing conditions and other. （1） formulation currently selection CPE as is impact modifier, its in chlorine quality separation is 36% CPE for PVC modified most good, use amount generally in 8-12 quality 份, crystallization degree and 玻璃化 temperature degree relatively low, tool has good elastic property and and PVC versus property. （2） type 材断面 structure high quality PVC type tool has good structure. usually lower, small structure excellent large structure, upper inner 筋 位置设置 need 适宜. increase inner thick degree, in inner and 壁连接处 using/adopting 圆弧 渡, has improve/increase low temperature impact strong/high degree. （3） injection molding processing mold injection molding processing mold for low temperature impact strong/high degree effect/influence main/primary in melt pressure and cooling 时 应 force control upper. formulation 确定, melt pressure main/primary and has 关. from 口模出 type different cooling methods, generate different force distribution. force in 方PVC type low temperature impact strong/high degree 就差. PVC type to cold easy generate large force, therefore type cooling water runner non key/critical, water temperature generally control in 14℃-16℃, using/adopting cold methods has improve/increase PVC type low temperature impact strong/high degree. ensure injection molding processing mold most 佳状态, 定期清理口模, 避免因 long time production let 杂质堵塞口模, formed material decrease/reduce, 支撑筋 thin, effect/influence low temperature impact strong/high degree. 定期清理定 type can ensure type 模足够 定 type true degree and water amount, ensure type production process in by separation cooling, decrease/reduce defect, reduce internal stress. （4）塑化 degree a large amount of research and testing table/sheet 明, PVC type low temperature impact strong/high degree most value is in degree is 60%-70%时 to. experience table/sheet 明, “ high temperature low speed ” and “ low temperature high speed ” can to 同样 塑化 degree. in production in low temperature high speed, is low temperature can reduce add hot consumption electrical amount, high speed also can improve/increase production efficiency, and di screw extrusion machine high speed extrusion 时剪切 function very obvious. （5） testing conditions GB/T8814-2004 in for low temperature impact experiment/testing has 严格 规定, type long degree, quality, semi 径, Sample cold conditions, testing ring and other, is make experiment/testing 结果准确, need 严格遵守 upper 述规定. its in: “落锤 impact in Sample in 心位置 upper ”应理 understanding is “ make impact in Sample type in 心位置”, this testing more has 现实意义. improvement low temperature impact property can measures lower: 1.严格检查 use material quality, attention/notes 口模出 material and true material material 状态, 口模出 material color 一致, has gloss degree, material uniform, use 手捏时 need has relatively good elastic property, machine true material material 呈“豆腐渣”状态, 初步塑化时不 can light, machine electrical 流, machine pressure and other parameters 应平稳. 2. specification process control, ensure 塑化效果. temperature degree control is “盆”式 process, from extrusion machine to machine add hot temperature degree 变化应 is “盆” type, machine 筒三, temperature degree low, make material material 由“ outer hot inner cold ”逐步变 is “ inner outer balanced ”, ensure material material hot uniform. in formulation 不变 情况 lower, extrusion process need has large 变化. 笔者曾经 has this 样 经历: positive production 时80 frame appearance light slip fine 腻, low temperature impact experiment/testing is 10 Sample loss 1; in 清理 injection molding parts mold again production 时, 因未按以 front process extrusion, formed appearance light slip, has small 波浪, low temperature impact experiment/testing is 10 Sample loss 6 （ table/sheet 2）. this formulation 不变时, “ has good appearance has good inner in ” experience. table/sheet 2 different extrusion process for type quality effect/influence. strong/high degree strong/high degree is PVC type welding 後焊角承受 outer force can force, and PVC type 材本身 and welding process has 关. excellent type if welding good, strong/high degree 也会不 combined 格. （1） welding lower material front will PVC type in and processing ring same temperature degree lower 放置16h above, this can anti low temperature PVC type in welding hot conditions lower generate force, 导致PVC type cracking. （2）切割 requirements need ensure lower material degree is 90° and its for property. lower material 後, need dry 净. （3） welding process welding temperature degree setting need combined 理, generally is 240℃-270℃. add hot time need and add hot temperature degree 协调统一, temperature time 选取也 very important. is ensure strong/high degree, can is improve/increase as efficiency shrink short cooling time. 同样80扇, in welding pressure, welding amount, welding temperature degree 不变 情况 lower, add hot time from 20s变 is 15s, holding pressure time from 30s变 is 15s, strong/high degree decline 近400N（ table/sheet 3）. its causes is holding pressure time short formed 焊角没 has full cooling solid 化, 焊缝处受急 cold formed strong/high degree decline. table/sheet 3 different welding process for strong/high degree effect/influence. （4） other welding process in, upper has material need and remove, and more 换焊布破 loss or 烧焦 方. machine 械清理沟槽不宜太 deep, anti reduce strong/high degree.