A brief analysis of the characteristics of waterproof rubber-containing heat shrinkable pipe and the production flow of heat shrinkable tube

Waterproof rubber-containing heat shrinkable pipe is also known as environmental protection with rubber heat shrinkable casing, its outer layer using high-quality, soft crosslinked polyolefin materials, the inner layer of hot melt glue composite processing. The outer material has the advantages of insulating anticorrosion and wear resistance, and the inner layer has the advantages of low melting point, waterproof, sealing and high adhesion. Waterproof adhesive double-walled tube is widely used in electronic equipment wiring waterproof, anti-leakage, power branch of the anti-corrosion protection, wire and cable repair, water pump and submersible pump wiring waterproof and other occasions. Suitable for insulation and sealing of irregular shapes. Features: ① shrinkage ratio 3:1,4:1;② flame retardant, sealing, waterproof, strain cushioning, environmental protection (ROHS), outer layer self-extinguishing; ③ starting shrinkage temperature 70 ℃, full shrinkage temperature 125℃;④ operating temperature range: -45℃~125℃;⑤ Melt temperature of the inner rubber layer: 70℃-100℃ ; ⑥ adhesive layer can be glued to plastic, rubber, metal. Our company can be tailored to the characteristics of a variety of different industries, can adapt to these harsh environmental design, with specific targeted products.

How to calculate the axial shrinkage of the heat shrinkable tube, the calculation formula of the shrinkage rate of the axial (length direction) of the heat shrinkable casing: shrinkage = (length before shrinkage-length after total shrinkage)/length of x100% before shrinkage.

Thermal shrinkage products in the storage and transport process to avoid direct sunlight or ambient temperature of more than 60 degrees, when the ambient temperature of more than 60 degrees, heat shrinkage products can occur partial contraction.

The production process of the double-walled heat shrinkable tube of the heat shrinkable tube is divided into five steps, usually in turn, the Masterbatch granulation, pipe extrusion, irradiation crosslinking, pipe expansion, printing packaging.

The first is the Masterbatch granulation, the Masterbatch granulation is to set the formula of raw materials for the material, and then through the mixer mixing to create a corresponding heat shrinkable tube required masterbatch particles.

Secondly, pipe extrusion, pipe extrusion is the above masterbatch into the mixer, according to a certain process of extrusion of qualified pipe, extrusion process pipe wall thickness, deflection of the situation on the quality of the heat shrinkable casing have a greater impact.

Third, irradiation crosslinking (referred to as irradiation), irradiation crosslinking process is the most critical process in the manufacture of heat shrinkable pipe, pipe extrusion, the need to go through the electronic accelerator irradiation, high-temperature heat shrinkable pipe internal polymer material crosslinking degree increased, so that it becomes a network-like structure, chain and chain between the chemical bond link, There is a strong interaction force. Irradiation crosslinking degree to be appropriate to create a qualified heat shrinkable tube, irradiation crosslinking through the large, the pipe can not be expanded, cross-linking through small, the pipe can not expand up, or can not expand to a larger multiple, easy to crack, and the manufacture of heat shrinkable tube shrinkage is not enough, the shrinkage effect is not good.

Its four is pipe expansion. After irradiation crosslinking, the heat shrinkable tube passes through the expander, so that the resistance of the pipe chain is very strong, the retractable force is not enough to customer service this resistance, so in the natural state, it remains dilated after the shape.

Finally, the print packaging.

简析防水含胶热缩管的特点及热缩管的生产流程

防水含胶热缩管又称环保带胶热缩套管，其外层采用优质、柔软的交联聚烯烃材料，内层热熔胶复合加工而成。外层材料具有绝缘防腐、耐磨等优点，内层具有低熔点、防水、密封和高粘接性等优点。防水含胶双壁管广泛应用于电子设备的接线防水、防漏气；电线分支处的防腐保护，电线电缆的修补，水泵和潜水泵的接线防水等场合。适应于不规则形状的绝缘及密封。特点：①收缩倍率3：1，4：1；②阻燃性，密封、防水、应变缓冲、环保（ROHS）、外层自熄；③起始收缩温度70℃，完全收缩温度125℃；④工作温度范围:-45℃～125℃；⑤内胶层熔化温度：70℃-100℃；⑥胶层可粘接塑料，橡胶，金属。我公司可针对各种不同行业的特点，可适应于这些苛刻环境设计的，具有专门针对性的产品。

热缩管轴向收缩率如何计算，热缩套管轴向（长度方向）收缩率计算公式：收缩率=（收缩前长度-完全收缩后长度）/收缩前长度×100%。

热缩产品在保管和运输过程中要避免阳光直射或环境温度超过60度，当环境温度超过60度，热收缩产品可发生部分收缩。

热缩管的双壁热缩管生产流程分五个步聚，通常依次是母料造粒、管材挤出、辐照交联、管材扩张、印字包装。

首先是母料造粒，母料造粒是将设定配方的原材料进行取料，然后在经过密炼机混炼制造出对应热缩管所需要母料粒子。

其次是管材挤出，管材挤出就是将上述母料投入密炼机，按一定工艺挤出合格的管材，挤出过程中管子的壁厚、偏壁情况对热缩套管的质量都有较大影响。

其三是辐照交联（简称为辐照），辐照交联工艺算是热缩管制造中最关键的工艺，管材挤出好后，需要经过电子加速器进行辐照、将高温热缩管管材内部高分子材料交联度加大，使它成为一个网一样结构，链段和链段之间都有化学键相链接，存在较强相互作用力。辐照交联度要合适才能制造出合格热缩管，辐照交联度过大，管子就无法扩张，交联度过小，管子也扩张不起来，或者不能扩张到较大的倍数，容易裂开，并且制造而成热缩管的收缩力也不够，回缩效果不好。

其四是管材扩张。辐照交联后的热缩管再通过扩张机，使管的链段发生伸曲的阻力很大，回缩的内应力不足以客服这种阻力，所以自然状态下，就保持扩张后形状。

最后是印字包装。