CN106346739B - 一种实壁co管的生产工装及生产方法 - Google Patents

一种实壁co管的生产工装及生产方法 Download PDF

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CN106346739B
CN106346739B CN201610781307.9A CN201610781307A CN106346739B CN 106346739 B CN106346739 B CN 106346739B CN 201610781307 A CN201610781307 A CN 201610781307A CN 106346739 B CN106346739 B CN 106346739B
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swollen
pipe
swollen mould
solid wall
temperature
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CN106346739A (zh
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王龙飞
蒋生龙
郑玲玲
李文水
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Zhejiang Feilong Pipe Group Co., Ltd
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FEILONG TUBE INDUSTRY Co Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/92—Measuring, controlling or regulating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/30—Extrusion nozzles or dies
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/30—Extrusion nozzles or dies
    • B29C48/32—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92504—Controlled parameter
    • B29C2948/92704—Temperature
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92819—Location or phase of control
    • B29C2948/92857—Extrusion unit
    • B29C2948/92876—Feeding, melting, plasticising or pumping zones, e.g. the melt itself
    • B29C2948/92895—Barrel or housing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92819—Location or phase of control
    • B29C2948/92857—Extrusion unit
    • B29C2948/92904—Die; Nozzle zone
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2023/00—Tubular articles
    • B29L2023/22—Tubes or pipes, i.e. rigid

Abstract

一种实壁CO管的生产工装，挤塑模头与真空水冷装置之间设有抻胀模，抻胀模经一螺杆固定在芯模上，所述抻胀模呈锥状，抻胀模的细端朝向挤塑模头，抻胀模的粗端朝向真空水冷装置，抻胀模的细端至粗端光顺过渡，抻胀模的细端直径D1、芯模直径d和抻胀模的粗端直径D2之间的关系为：0.8d＜D1＜0.95d，1.8d＜D2＜2.2d。由锥形双螺杆挤出机塑化挤出的实壁CO管毛坯，在110‑130℃的热风保护下仍具有可塑性，经由抻胀模的抻拉膨胀，管壁壁厚的均匀度更好，生成一种密实的层状结构，作用在管壁上的应力就通过分子链内原子间的作用力抵消掉了，分子链被拉伸，大大提高了管材的机械强度、韧性和抗开裂能力等物理性能。

Description

一种实壁CO管的生产工装及生产方法
技术领域
本发明属于实壁CO管的生产技术领域，具体是涉及一种实壁CO管的生产工装及生产方法。
背景技术
现有技术中，使用锥形双螺杆挤出机塑化挤出实壁CO管后，经由空气段稍加冷却预成型直接进入真空水冷装置中固化成型，参看图1，由挤塑模头的外模和芯模决定实壁CO管的管径。在生产过程中，由于进料压力和温度会波动，往往使得PVC管的壁厚稍有变化，降低其强度；再就是管壁中分子结构随意分布，其强度和韧性难以进一步提高，这些都制约了实壁CO管的应用。
发明内容
本发明主要是解决现有技术所存在的技术问题，提供了一种实壁CO管的生产工装及生产方法。
本发明的上述技术问题主要是通过下述技术方案得以解决的：一种实壁CO管的生产工装，包括由外模和芯模构成的挤塑模头，挤塑模头后面设有真空水冷装置，所述挤塑模头与真空水冷装置之间还设有抻胀模，抻胀模经一螺杆固定在芯模上，所述抻胀模呈锥状，抻胀模的细端朝向挤塑模头，抻胀模的粗端朝向真空水冷装置，抻胀模的细端至粗端光顺过渡，抻胀模的细端直径D1、芯模直径d和抻胀模的粗端直径D2之间的关系为：0.8d＜D1＜0.95d，1.8d＜D2＜2.2d；所述挤塑模头与抻胀模细端之间的距离为L，抻胀后所述实壁CO管的壁厚为H，则抻胀后所述实壁CO管的外径为D＝D2+2H，D与L之间的关系为：D为20-60mm时，L为200mm；D为65-110mm时，L为300mm；D为120-250mm时，L为400mm；D为280-550mm时，L为600mm。
一种使用上述生产工装生产实壁CO管的方法，包括：利用锥形双螺杆挤出机塑化挤出时，料筒Ⅰ区的温度为175-185℃，料筒Ⅱ区的温度为190-200℃，料筒Ⅲ区的温度为205-215℃，料筒Ⅳ区的温度为200-210℃，合流芯的温度为180-195℃，模具Ⅰ区的温度为165-170℃，模具Ⅱ区的温度为175-185℃，模具Ⅲ区的温度为190-205℃，口模的温度为210-230℃；所述实壁CO管自毛坯到抻胀成型的整个过程都在110-130℃的热风保护下进行，抻胀前所述实壁CO管的壁厚h与抻胀后所述实壁CO管的壁厚H之间的关系为1.8H＜h＜2.2H。
为了使得实壁CO管能顺利通过抻胀模的抻拉膨胀，本发明合理设计了料筒各区、合流芯、模具各区和口模的温度，以及设计了实壁CO管自毛坯到抻胀成型在110-130℃的热风保护下进行。在挤塑模头与真空水冷装置之间增设抻胀模，由锥形双螺杆挤出机塑化挤出的实壁CO管毛坯，在110-130℃的热风保护下仍具有可塑性，由于管壁的内侧比外侧温度高，管壁的内侧比外侧更具可塑性，仍具可塑性的实壁CO管经由抻胀模的抻拉膨胀，管壁壁厚的均匀度更好，同时对挤出生产的管坯进行径向扩张实现分子取向，即通过物理改性引起分子的重新排布，由原来的随意分布变成辐射状分布，生成一种密实的层状结构，作用在管壁上的应力就通过分子链内原子间的作用力抵消掉了，由于分子链被拉伸，需要更大的作用力才能将其拉得更长，大大提高了管材的机械强度、韧性和抗开裂能力等物理性能。经测试，本发明生产出来的实壁CO管抗压强可达7000pSi以上，比普通实壁CO管提高约80％，抗拉强度比普通实壁CO管提高约80％，抗冲击强度是普通实壁CO管的近4倍。
附图说明
图1是现有技术中一种实壁CO管生产工装的结构示意图；
图2是本发明的一种结构示意图；
图3是本发明的一种剖视结构示意图。
图中，1-挤塑模头，2-芯模，3-外模，4-实壁CO管，5-真空水冷装置，6-抻胀模，7-螺杆。
具体实施方式
下面通过实施例，并结合附图，对本发明的技术方案作进一步具体的说明。
实施例：参看图2-3，一种实壁CO管的生产工装，包括由外模和芯模构成的挤塑模头，挤塑模头后面设有真空水冷装置，所述挤塑模头与真空水冷装置之间还设有抻胀模，抻胀模经一螺杆固定在芯模上，所述抻胀模呈锥状，抻胀模的细端朝向挤塑模头，抻胀模的粗端朝向真空水冷装置，抻胀模的细端至粗端光顺过渡，抻胀模的细端直径D1、芯模直径d和抻胀模的粗端直径D2之间的关系为：0.8d＜D1＜0.95d，1.8d＜D2＜2.2d。所述挤塑模头与抻胀模细端之间的距离为L，抻胀后所述实壁CO管的壁厚为H，则抻胀后所述实壁CO管的外径为D＝D2+2H，D与L之间的关系为：D为20-60mm时，L为200mm；D为65-110mm时，L为300mm；D为120-250mm时，L为400mm；D为280-550mm时，L为600mm。
一种使用上述生产工装生产实壁CO管的方法，包括：利用锥形双螺杆挤出机塑化挤出时，料筒Ⅰ区的温度为175-185℃，料筒Ⅱ区的温度为190-200℃，料筒Ⅲ区的温度为205-215℃，料筒Ⅳ区的温度为200-210℃，合流芯的温度为180-195℃，模具Ⅰ区的温度为165-170℃，模具Ⅱ区的温度为175-185℃，模具Ⅲ区的温度为190-205℃，口模的温度为210-230℃；所述实壁CO管自毛坯到抻胀成型的整个过程都在110-130℃的热风保护下进行，抻胀前所述实壁CO管的壁厚h与抻胀后所述实壁CO管的壁厚H之间的关系为1.8H＜h＜2.2H。
为了使得实壁CO管能顺利通过抻胀模的抻拉膨胀，本发明合理设计了料筒各区、合流芯、模具各区和口模的温度，以及设计了实壁CO管自毛坯到抻胀成型在110-130℃的热风保护下进行。在挤塑模头与真空水冷装置之间增设抻胀模，由锥形双螺杆挤出机塑化挤出的实壁CO管毛坯，在110-130℃的热风保护下仍具有可塑性，由于管壁的内侧比外侧温度高，管壁的内侧比外侧更具可塑性，仍具可塑性的实壁CO管经由抻胀模的抻拉膨胀，管壁壁厚的均匀度更好，同时对挤出生产的管坯进行径向扩张实现分子取向，即通过物理改性引起分子的重新排布，由原来的随意分布变成辐射状分布，生成一种密实的层状结构，作用在管壁上的应力就通过分子链内原子间的作用力抵消掉了，由于分子链被拉伸，需要更大的作用力才能将其拉得更长，大大提高了管材的机械强度、韧性和抗开裂能力等物理性能。经测试，本发明生产出来的实壁CO管抗压强可达7000pSi以上，比普通实壁CO管提高约80％，抗拉强度比普通实壁CO管提高约80％，抗冲击强度是普通实壁CO管的近4倍。
最后，应当指出，以上实施例仅是本发明较有代表性的例子。显然，本发明的技术方案并不限于上述实施例，还可以有许多变形。本领域的普通技术人员能从本发明公开的内容直接导出或联想到的所有变形，均应认为是本发明的保护范围。

Claims (2)

1.一种实壁CO管的生产工装，包括由外模和芯模构成的挤塑模头，挤塑模头后面设有真空水冷装置，其特征在于所述挤塑模头与真空水冷装置之间还设有抻胀模，抻胀模经一螺杆固定在芯模上，所述抻胀模呈锥状，抻胀模的细端朝向挤塑模头，抻胀模的粗端朝向真空水冷装置，抻胀模的细端至粗端光顺过渡，抻胀模的细端直径D1、芯模直径d和抻胀模的粗端直径D2之间的关系为：0.8d＜D1＜0.95d，1.8d＜D2＜2.2d；所述挤塑模头与抻胀模细端之间的距离为L，抻胀后所述实壁CO管的壁厚为H，则抻胀后所述实壁CO管的外径为D＝D2+2H，D与L之间的关系为：D为20-60mm时，L为200mm，D为65-110mm时，L为300mm，D为120-250mm时，L为400mm，D为280-550mm时，L为600mm。
2.一种使用权利要求1所述生产工装生产实壁CO管的方法，其特征在于所述生产方法包括：利用锥形双螺杆挤出机塑化挤出时，料筒Ⅰ区的温度为175-185℃，料筒Ⅱ区的温度为190-200℃，料筒Ⅲ区的温度为205-215℃，料筒Ⅳ区的温度为200-210℃，合流芯的温度为180-195℃，模具Ⅰ区的温度为165-170℃，模具Ⅱ区的温度为175-185℃，模具Ⅲ区的温度为190-205℃，口模的温度为210-230℃；所述实壁CO管自毛坯到抻胀成型的整个过程都在110-130℃的热风保护下进行，抻胀前所述实壁CO管的壁厚h与抻胀后所述实壁CO管的壁厚H之间的关系为1.8H＜h＜2.2H。
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CN105599314A (zh) * 2015-12-28 2016-05-25 山东华信塑胶股份有限公司 一种双轴取向聚氯乙烯管材的连续成型装置及工作方法

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