Shanghai Daoqin Plastics Co., Ltd.

         plastics in blow molding upper can separation is large type: extrusion — blow molding and injection — blow molding.

        两者 main/primary different in type made 备, rear blow molding process same. in this types molding method upper 开展起 has: extrusion — tensile — blow molding (简称挤—拉—吹), injection — tensile — blow molding (简称注—拉—吹)以 and more 层映塑 and other.

         injection - blow molding (简称注-吹) plastics bottle is using/adopting injection molding method will plastics made formed has type 坯, again type hot to blow molding in blow molding in products. 注-吹 in container has flash, dimensional stability good, bottle and quality excellent 良, type thick degree can 预先调理, products gloss degree good, raw materials. 但注-吹 molding combined 适消费 large type and outer complex container, also due to need use injection and blow molding mold, therefore equipment investment relatively large.

        注-吹 in container outer mono small type bottle is 主, it can use polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP) and polystyrene (PS), polyester, polyamide (PA) and other multiple resin 消费. main/primary used for 医药, food, product and other packaging used for in blow molding plastics types type has polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), polystyrene (PS), polyester, polycarbonate (PC), polyamide (PA), acid fiber and poly shrink aldehyde resin and other. its in high density polyethylene (PE) consumption amount 占首位. it 普遍应 used for food, chemical industry and liquid packaging.

         polymer/macromolecule amount polyethylene (PE) suitable for manufacturing large type material and and other. polyvinyl chloride (PVC) due to has relatively good transparent degree and gas property, therefore in product and agent packaging to application. 随 无毒 polyvinyl chloride (PVC) resin and additives development, and tensile blow molding technology 开展, polyvinyl chloride (PVC) container in food packaging use amount speed increase, and 曾经开端 used for and its it has oxidation carbon gas material packaging. polyester material is year in blow molding new type material. due to its products tool has gloss appearance, excellent transparent property, relatively high force strong/high degree and container inner material product tube/pipe property relatively good, waste material 燃烧处置时不污染 ring and other advantages, therefore in packaging bottle 方面开展 very fast, especially in resistant pressure plastics food container 方面 运 use most is 普遍. polypropylene (PP) its resin modified and processing technology 进步, use amount year increase.

        一, main/primary raw materials and type formulation

        （ l ） polyethylene (PE) 　普通 selection melt is l ～ 6 polyethylene (PE) resin.

        （ 2 ） polypropylene (PP) 　普通选网 melt is 2～4 polypropylene (PP) resin.

        （ 3 ） polystyrene (PS) 　普通 selection general purpose type or impact resistant type injection grade polystyrene (PS) resin.

        （ 4 ） polyvinyl chloride (PVC) hard transparent bottle formulation.

        二, plastics production main/primary equipment and features

        （ 1 ） extrusion machine and machine 头　 and 普通挤-吹 method equipment same.

        （ 2 ） type 坯处置安装　由 extrusion machine extrusion tube/pipe type 坯, need 经 该安装停止切断, 底部熔 combined and processing, made formed tube/pipe has type 坯.

        （ 3 ） type add hot 安装　 type add hot has 烘箱, add hot sleeve/set 筒, add hot and other multiple, add hot methods can use electrical add hot or outer add hot. add hot need can temperature balanced add hot, make type inner outer temperature amount decrease small.

        （ 4 ） tensile 安装　 has tensile rod and tensile tool types:

        ① tensile rod 　 tensile rod from type upper 部插入, in liquid pressure function lower type 坯底部, 停止纵 toward tensile, rear rod upper gas 孔通入紧 shrink gas 吹胀, 停止径 toward tensile. more tensile molding using/adopting this type of tensile 安装.

        ② tensile tool 　 tensile tool from external tube/pipe type 坯 两端, in liquid pressure function lower 停止纵 toward tensile, rear again 吹胀停止径 toward tensile. and 底部都 has flash demand 修整, flash 经破碎 can recycling application.

        （ 5 ）挤－拉－吹 specialized molding machine 　国 outer has multiple type and specifications 挤-拉-吹 specialized molding machine, currently inner 尚无此 specialized equipment.

        三, plastics production process

        注-吹 molding upper is injection molding type and blow molding products process formed, injection molding type also is 整 消费 process key/critical.

        （ 1 ） injection molding type process control.

        ① injection molding temperature degree 　 injection temperature degree and material types type and features, injection molding machine type type and products thick degree and other elements has 关. for crystallization property resin, polyethylene (PE), polypropylene (PP) and other, injection temperature degree high its melting point. for 无定形 polymer, polystyrene (PS), polyvinyl chloride (PVC), injection temperature degree need high its viscous temperature degree. melt low resin ratio melt high resin injection temperature degree need high 一. use 柱塞式 injection molding machine ratio screw injection molding machine processing temperature degree need high 一. thin type ratio thick type demand injection temperature degree high. polystyrene (PS) injection temperature degree is 140℃ ～ 240℃, polyethylene (PE) is 150℃ ～ 280℃, polypropylene (PP) is 205℃ ～ 285℃, polyvinyl chloride (PVC) is 160℃ ～ 190℃. injection mold temperature degree is 40℃ ～ 80℃.

        ② injection pressure 　普通 resin melt low, type thin, injection pressure relatively high, relatively low. 柱塞式 injection molding machine ratio screw injection molding machine demand pressure high. in ensure quality amount lower, can can using/adopting relatively low injection pressure. polystyrene (PS) injection pressure is 58.8 ～ 107.9MPa, polyethylene (PE) is 58.8 ～ 98.06MPa, polypropylene (PP) is 54.9 ～ 98.06MPa, polyvinyl chloride (PVC) is 78.4 ～ 127.5MPa.

        （ 2 ） blow molding process control and 挤－吹 molding blow molding process same.

        四, main/primary equipment and features

        （ 1 ） type injection machine 　 and injection molding machine structure same, injection pressure relatively low, screw long ratio can small 一, shrink ratio 也不宜 large.

        （ 2 ） mold 　包括 injection mold and blow molding mold. injection molding type mold and injection molding mold material and processing 请求根本 same, 但芯模必需 is in 空, 以便通入紧 shrink gas. blow molding mold and 挤-吹 molding mold same.

        （ 3 ） demolding 安装　 and 挤-吹 molding different, blow molding process formed rear, blow molding mold, will belt/tape molding products 芯模送至脱 film 安装, demolding sheet/plate will products and separation 开.

        五, product specification

         injection - blow molding plastics bottle currently 尚无国标 and 部标, product specification can polyethylene (PE) blow molding specification, as necessary positive. 但同一 types raw materials 注-吹 in container ratio 挤-吹 in container property can excellent 秀.

         large type in container 普通指容积 in 50L above various made 桶体, 罐体, 贮槽, and other large type in products. raw materials polyethylene (PE) resin is 主, molding process main/primary is extrusion - blow molding method and molding method.

         extrusion - blow molding large type container molding method and plastics 桶根本 same, in raw materials and equipment 方面略 has difference.

         main/primary raw materials 请求　消费 plastics 桶普通以 low density polyethylene (PE) resin or high, low density polyethylene (PE) resin mixed combined material is 主, 而消费 large type container high density polyethylene (PE) and polymer/macromolecule amount polyethylene (PE) resin is 主.

         main/primary equipment and features

        消费 large type container extrusion machine and blow molding 安装均 and plastics equipment same, in extrusion machine material and machine between increase material device. due to large type products type very large, false extrusion machine extrusion, type 坯则会呈现自 heavy 惹起 严 heavy phenomenon, formed products toward thick 不匀. meanwhile extrusion time long, make type cooling temperature low, effect/influence blow molding quality.

         increase material device rear, extrusion machine will melt material material 连续挤入储 material device, 当贮存 material material to 达一定 amount 时, pressure material fast speed will material material one-time pressure 出, formed thick degree 平均, temperature degree type 坯. increase material device can decrease/reduce type 坯垂伸, type temperature degree, also can use relatively small extrusion machine large type products.

        六, plastics product standards

         extrusion - blow molding large type in container currently 尚无国, standards, can GB 13508 一 92 polyethylene (PE) blow molding standards as necessary positive. PETP soft material bottle QB1868 一 93 standards.

         extrusion - tensile - blow molding (简称挤-拉-吹) plastics bottle is through extrusion method will resin made formed tube/pipe type 坯, again 底部熔 combined formed has type 坯, rear will type 坯处理至 use plastics tensile temperature degree, internal (tensile rod) or external (tensile tool) machine force function 进行纵 toward tensile, meanwhile or rear pressure shrink gas 吹胀进行径 toward tensile made in products.

         plastics di tensile rear separation heavy new toward, therefore products impact tough property, low temperature strong/high degree, transparent degree, surface gloss degree, rigid property and retardant property can and other has obvious improvement and improve/increase. in addition, tensile rear products thick decrease thin, can raw materials, reduce cost. currently used for production 挤-拉-吹 in container plastics main/primary is polyvinyl chloride (PVC) and polypropylene (PP), products small type, thin bottle is 主, used for food, material, product, day product and other packaging.

        挤拉-吹 also separation is method and method types. method type manufacturing, tensile, blow molding in equipment in 连续进行, also hot method. method type manufacturing in time, and equipment upper, and add hot, tensile, blow molding separation 开进行, also is cold method.

         main/primary raw materials and type formulation: for polypropylene (PP) resin requirements and polyvinyl chloride (PVC) container formulation, and extrusion - blow molding container basic same.

        消费 process: 挤-拉-吹 method in extrusion type and blow molding process control upper, and 挤-吹 method same.

         lower focus/key point tensile process control.

        （ 1 ） tensile temperature degree

         control combined tensile temperature degree is di tensile key/critical, will to make plastics separation heavy new toward 排列 目. for non crystallization property polyvinyl chloride (PVC) 说, using/adopting method, type can from extrusion 时 190℃ ～ 200℃ 宜接 cooling to 90℃ ～ 100℃, tensile and blow molding. this ratio it 玻璃化 temperature degree high 出 10℃ ～ 20℃, is most tensile temperature degree. for crystallization property polypropylene (PP) 说, using/adopting method, type need has cooling.

         from extrusion 时 210℃ ～ 230℃ 疾 speed cooling 至 90℃ ～ 105℃ between crystallization temperature degree, 抑止球晶 构 formed, rear again add hot to 玻璃化 temperature degree and melting point temperature degree between 150℃ ～ 160℃ 停止 di tensile. tube/pipe polyvinyl chloride (PVC) also is polypropylene (PP), false using/adopting method, demand for front made formed type heavy new add hot to tensile temperature degree, again tensile and blow molding.

        （ 2 ） tensile rate

         remove tensile temperature degree and other conditions outer, di tensile products separation toward is tensile rate 决议, tensile rate products property can 改良. tensile rate is tensile ratio and ratio 乘积, tensile ratio is products long degree and type long degree ratio, is toward tensile rate. ratio is products most large and type 坯直径之 ratio, is toward tensile rate. tensile rate low, to separation heavy new toward and improvement products property can function. tensile rate high, 则会惹起资 material loss make processing conditions easy control. polyvinyl chloride (PVC) tensile rate 取 4 ～ 6, polypropylene (PP) 取 6 ～ 10.