Heat Shrinkable Tube Development, Application, Production Materials Introduction

- Nov 08, 2018-

Brief introduction of heat shrinkable pipe development, application and production materials

1. What is a heat shrinkable casing?

Referring to heat shrinkable casing, according to the industry, the heat shrinkable casing can be divided into three categories: thin-walled heat shrinkable casing, medium wall heat shrinkable casing and thick wall heat shrinkable casing. The heat shrinkable casing is made of polyolefin material and shrinks in diameter after heating. Its diameter and thickness vary depending on the caliber. Due to different expansion processes, the expansion rate of heat shrinkable tubes, shrinkage will also be different, there are twice times, 3 times times, 4 times times or higher. Thermal shrinkage casing is often used in electrical engineering wire conductor connection and wire joints, insulation protection of the environment protective effect. It can also be used to bundle bound wires during wire repair to protect wires and small terminals, thus increasing the sealing of electrical junction boxes.

2, heat shrinkable casing application applications:

Place the heat shrinkable tube at the junction of the Wire and heat it with an oven, hot air gun, or similar tool. If you do not have these tools, you can also use a lighter or soldering iron (close but not touching), shrinkage is convenient, but the effect is general. A high-shrinkage heat shrinkable casing (conventional heat shrinkable casing is twice times shrinkage) can be used for connectors with no size. This provides good electrical insulation, isolation of dust, solvents and other foreign bodies. If heated too much, the heat shrinkable tube will melt and scorch just like any other plastic. A thermal shrinkage casing with a hot melt adhesive on the inner layer can provide a good sealing effect and better adhesion. The ordinary depends only on the friction between the material and the shrinkage and tightness of the heat shrinkable tube. Since the early 1970s, heat shrinkable tubes have been used extensively on the fiberglass spiral antennas of walkie-talkies. Millions of of antennas already use this versatile heat shrinkable casing. Thermal shrinkage casing is a thermoplastic material such as polyolefin, fluorinated polymers (such as FEP,PTFE or Kynar), PVC, neoprene, silicone rubber or fluorine rubber production.

Due to the use of different materials, there are two types of heat shrinkage: first, if the material contains many monomers, the pipe is heated to the softening point when the monomer will be polymerized, monomer polymerization will increase the density of the material, thus taking up less space, and achieve the effect of shrinkage. Second, the other is based on expansion, the production process is usually normal extrusion pipe, when heating above the polymer melting point of the mechanical external force to stretch the pipe or by the gas pressure expansion; Finally, cool quickly. Later, when used, the heat shrinkable casing is heated and the pipe shrinks back to its pre-expansion size. After extrusion, the material is crosslinked by using an electron beam with a peroxide. This crosslinking helps to keep the casing in its shape, whether before or after shrinkage, and if specifically required, the heat shrinkable casing can add UV stabilizers.

3. Heat shrinkable Casing Material

Different applications require different materials: PTFE (fluorine polymer) tubes have a wide operating temperature range (-55-175 ℃), low coefficient of friction, and high resistance to chemicals and puncture. Fluorine-containing polymers with high chemical resistance, fluorine rubber, and the other is widely used in hydraulic equipment. It has a high degree of flexibility and has a very high operating temperature of 55-220 ℃, making it suitable for thermal sensitive device protection.

High temperature applications of polyvinylidene fluoride (PVDF) tubes. Ethylene fluoride Propylene (FEP) is a lower cost alternative to PTFE, and elastic tubes maintain a high degree of flexibility even at low temperatures and meet strict international specifications. Their operating temperature range is-75 to. The material is resistant to many chemical substances (including diesel and gasoline) and has good abrasion resistance even in harsh environmental conditions. The common shrinkage ratio is 2:1.

Silicone rubber provides excellent scratch-resistant, high elasticity. The most common type of polyolefin heat shrinkable casing, with a maximum continuous use temperature from 55 to 125°c, and is used in military, aviation and rail industries. They are flexible and fast shrinkage, and the color of the product (including transparent) ranges widely, suitable for wires of various colors. In addition to black, they tend to have lower UV resistance, only black advice for outdoor use. The common shrinkage ratio is 2:1, while the high grade polyolefin heat shrinkage can be 3:1.

PVC tubes are available in a variety of colors and can be used outdoors. Thermal shrinkage sleeves for other special materials are present for high resistance under diesel and aviation fuels, or for weaving fibers to increase wear resistance in harsh environments.

热缩管发展、应用、生产材料简介

1、 什么是热缩套管?

    提及热缩套管,按照行业内的说法,可以将热缩套管分成三类:薄壁热缩套管、中壁热缩套管和厚壁热缩套管。热缩套管是由聚烯烃材质制成,加热后直径缩小。它的直径和厚度随着口径不同而有差异。由于扩张工艺不同,热缩管的扩张率,收缩率也会有不同,有2倍,3倍,4倍甚至更高。热缩套管常用于电气工程的电线导体的连接处和电线接头处,起绝缘保护环境防护作用。也可用于电线修复时捆绑束缚导线,以保护导线和小端子,从而增加电气接线盒的密封性。

2、 热缩套管应用应用:

    把热缩管放在电线的连接处,用烤箱、热风枪或类似工具加热。如果没有这些工具,也可以用打火机或烙铁(接近但不接触),收缩方便,但效果一般。形状不规格的接头可用高倍收缩的热缩套管(常规热缩套管为2倍收缩率)。这提供了良好的电气绝缘,隔离灰尘,溶剂和其他异物。如果加热过头了,热缩管也会熔化烧焦就像其他塑料一样。有种内层有热熔胶的热缩套管可以提供一个良好密封效果和更好附着力。普通的仅依靠材料间的摩擦力及热缩管收缩松紧程度。20世纪70年代初以来,热缩管大量使用在对讲机的玻纤螺旋天线上。已有数百万的天线使用了这种多功能的热缩套管。热收缩套管是一种热塑性材料,如聚烯烃,含氟聚合物(如FEP,PTFE或的Kynar),PVC,氯丁橡胶,硅橡胶或氟橡胶生产。

    由于使用材料不同,热缩方式有两种:一、如材料中含有许多单体,管子被加热到软化点时单体就会聚合,单体聚合时就增加了材料的密度,因此占用更少的空间,而达到收缩的效果。二、另一种是以扩张为基础,生产过程通常为正常挤出管材,在聚合物熔点以上加热时加以机械外力伸展管子或由气体加压膨胀;最后,迅速冷却。后来使用时,对热缩套管加热,管材将收缩回到扩张前的大小。材料在挤出后都通过使用电子束配合过氧化物交联。这种交联,有助于使套管保持其形状,不管是收缩前或收缩后,若特殊要求,热缩套管可以添加紫外线稳定剂。

3、热缩套管材料

    不同的应用需要不同的材料:PTFE(氟聚合物)管有较宽的工作温度范围(-55到175℃),低摩擦系数,和高耐化学品和穿刺 。具有高耐化学性的含氟聚合物,氟橡胶,另一个被广泛应用于液压设备 。它具有高度的灵活性,具有非常高的工作温度在-55至220℃,使得它适合对热敏感器件保护。

   聚偏二氟乙烯(PVDF)管的高温应用的。氟化乙烯丙烯(FEP)是一种成本更低的替代聚四氟乙烯,弹性管 即使在低温下保持高度的灵活性,并满足严格的国际规范。他们的工作温度范围是-75至150°C。该材料是耐许多化学物质(包括柴油和汽油),并具有良好的耐磨性,即使在恶劣的环境条件。常见的收缩比是2:1

    硅橡胶提供优良的抗刮耐磨,高弹性。聚烯烃热缩套管 最常见的一种,最高连续使用温度从-55到125°C,并且被用于军事,航空和铁路等行业。他们是灵活和快速收缩,产品的颜色(包括透明的)的范围很广,适用各种颜色的电线。除了黑色,他们往往有较低的抗紫外线,只有黑色建议为户外使用的。常见的收缩比是2:1,而高品位的聚烯烃热收缩可在3:1。

    PVC管可用多种颜色,可用于室外。其它特殊材料的热缩套管存在,是为在柴油和航空燃料下耐高电阻,或编织纤维增加在恶劣的环境中耐磨性。