First of all, double-walled heat shrinkable tube is an outer layer using high-quality, soft crosslinked polyolefin materials, the inner layer of hot melt glue composite processing into a hot shrinkage casing, the industry is also called double-walled tube or heat shrinkable casing. 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. Double-walled tubes are 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. Second, double-walled tube shrinkage ratio is generally 3:1, there are 4:1 of this shrinkage ratio, because the double wall heat shrinkage tube shrinkage is relatively large, can be applied to a lot of irregular shape material insulation seal, The caliber of the double-walled heat shrinkable tube ranges from 2.4-25mm, because the double wall heat shrinkable tube is the outer substrate and the inner layer Hot melt adhesive is co-extrusion bonding, so can not do a large caliber, the caliber is larger to use a separate glue of the middle wall heat shrinkable casing (this product later in detail), from the packaging point of view, 12.7mm and subsequent double-walled tubes are generally cut into a section to package ( The length of the package is 1.22 meters), because its flexibility has not allowed it to be packed in a plate, because there is hot melt glue, double wall heat shrinkable pipe wall thickness heat shrinkage tube than the ordinary electronic heat shrinkable tube thickness is much thicker, flexibility is correspondingly lower. Again, the outer layer of the double-walled heat shrinkable tube is soft, usually black, can also be processed into other colors, such as transparent double-walled heat shrinkable pipe, wall thickness is medium thickness, has a certain wear resistance and mechanical protection performance, pressure is generally greater than 10KV, can be used for 10KV extremely below voltage level of cable outer repair and connection insulation seal Waterproof, Its adhesive layer can be glued to plastic, rubber, metal and so on. Finally, the use of double-walled heat shrinkable tube is similar to that of ordinary heat shrinkable tube, his initial shrinkage temperature is 70 ℃, complete shrinkage temperature 125 ℃, internal glue layer melting temperature: 70℃-100℃, operating temperature range: -40℃~125℃, and double-walled heat shrinkable tube and ordinary heat shrinkable pipe, there are two requirements of environmental protection flame retardant, Usually this requirement is for the double-walled heat shrinkable tube of the outer substrate, generally this substrate and ordinary heat shrinkable tube formulation is similar, so UL,ROHS and other international certification is also practical, the export sometimes need to issue the relevant certification.

When we buy a double-walled heat shrinkable tube, the first thing to do is to determine the caliber and shrinkage ratio and color you need. General domestic sales of double-walled heat shrinkable tube shrinkage ratio is 3:1, export will have 4:1 of these double wall heat shrinkable pipe products. Color We generally choose black, because double-walled tube applications are still bad, other colors are not necessary, and special colors, manufacturers will charge special processing fees, and inside the color Masterbatch add will also increase the cost, so more expensive, but these are only because of customers, such as to some customers for transparent double-walled heat shrinkable tube. For double-walled heat shrinkable tubes, the caliber is generally fixed several, 2.4,3.0,4.5,6.0,9.0,12.0,15.0,19.0,25.0mm, for example, used in cable insulation seal waterproofing, if the outer diameter of the cable is 7mm, then we choose 9.0,12.0 both specifications can be, as to which one to choose or to see your own needs, and heat shrinkable tube selection caliber similar, large In the construction, shrinkage after the wall thickness is thicker, shrinkage relative to send some, the price is also much more expensive, small caliber may bring trouble to the construction, but the economy is good. The flame retardant performance of the double-walled heat shrinkable tube depends on the performance and metering of the flame retardant added in the formulation of the outer substrate, so the price of good flame retardant performance is also expensive, and ultimately it is the sealing waterproof performance of Sumitomo SUMITUBE Heat shrinkable casing, which depends on what hot melt glue the manufacturer is using, With good glue and bad glue effect high temperature heat shrinkage tube fruit is also not the same, of course, the price is not the same.

Automobile tubing protection with glue double-walled tube: the middle wall tube has SBRSM and RSFRM without glue medium wall tube Two, SBRSM with adhesive medium wall tube using high-quality polyolefin materials and environmental protection hot melt Adhesive layer composite, RSFRM without glue in the wall tube using high-quality polyolefin materials carefully processed, Widely used in low-voltage power insulation protection and mechanical strain cushioning and room wear protection, products with insulation, sealing waterproof (with glue in the wall), soft, outer layer self-extinguishing, environmental protection and other characteristics.

Main applications:

① the sealing insulation protection of the joints and terminals of low voltage power wires and cables;

② Wire, cable and a variety of mechanical products anti-extrusion and anti-wear;

Sealing protection of ③ marine cables;

④ pipeline anticorrosion and sealing;

⑤ with adhesive medium wall using environmentally friendly hot melt adhesive, the product insulation sealing is reliable, suitable for the RoHS directive requirements of the environment;

⑥ other places that require tight protection.

Product Usage Range:

① Operating Temperature: -45℃~125℃

② Shrinkage Temperature 125 ℃

Standard color: Black (can be customized in other colors)

合理采购双壁热缩管及汽车油管防护专用热缩管

首先双壁热缩管是一种外层采用优质、柔软的交联聚烯烃材料，内层热熔胶复合加工而成热缩套管，行业内也叫双壁管或热缩套管。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。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。其次双壁管收缩比一般是3：1，也有4：1这种收缩比的，由于双壁热缩管的收缩比较大，可以适用于很多不规则形状材料的绝缘密封，双壁热缩管的口径从2.4-25mm不等，因为双壁热缩管是外层基材和内层热熔胶是共挤粘合的，所以不能做很大的口径，口径再大就要用单独涂胶的中壁热缩护套管了（这个产品以后再详细讲），从包装上看，12.7mm及其以后的双壁管一般都是切成一段来包装（包装长度是1.22米），因为其柔韧性已经不允许其盘成一盘来包装了，因为里面有热熔胶，双壁热缩管壁厚热缩管比普通电子热缩管厚很多，柔韧性也相应低一些。再次双壁热缩管的外层材质是柔软的，通常是黑色，也可加工成其他颜色，如透明双壁热缩管等，壁厚是中等厚度，有一定耐磨及机械保护性能，耐压一般大于10KV，可用于10KV极其以下电压等级的电缆外层修补及连接处绝缘密封防水，其胶层可粘接塑料，橡胶，金属等。最后双壁热缩管的使用和普通热缩管相似，他的起始收缩温度是70℃，完全收缩温度125℃，内胶层熔化温度：70℃-100℃，工作温度范围:-40℃～125℃，且双壁热缩管和普通热缩管一样，有环保阻燃这两项要求，通常这项要求是针对双壁热缩管的外层基材的，一般这种基材和普通热缩管配方差不多，所以UL,ROHS等国际认证也是实用的，出口上有时候需要出具相关认证。

当我们采购双壁热缩管时，首先是要确定你需要的口径和收缩比以及颜色。一般国内销售的双壁热缩管收缩比都是3：1，外销会有4：1这双壁热缩管种产品。颜色我们一般选黑色，因为双壁管应用场合还是恶劣的，其他颜色没什么必要，再者特殊颜色，厂家会收取特殊加工费，还有里面的色母粒添加也会增加成本，所以比较贵，不过这些都因客户而已，比如就向有的客户供透明双壁热缩管。对于双壁热缩管的口径一般是固定几种，2.4，3.0，4.5，6.0，9.0，12.0，15.0，19.0，25.0mm，比如用在电缆绝缘密封防水上，如果电缆的外径是7mm，那么我们选择9.0，12.0这两种规格都可以，至于选哪一种还是得看您自己的需求，和热缩管选口径类似，大的便于施工，收缩后壁厚较厚，收缩相对送一些，价格也贵不少，小口径可能给施工带来麻烦，但是经济型好。双壁热缩管的阻燃性能就看外层基材的配方中所添加的阻燃剂的性能和计量了，所以阻燃性能好的价格也贵，最终要的还是住友SUMITUBE热缩套管的密封防水性能，这就要看厂家用的是什么热熔胶了，用好的胶和不好的胶效高温热缩管果也是不一样的，当然价钱也是不一样的。

汽车油管防护用带胶双壁管：中壁管有SBRSM带胶中壁和RSFRM不带胶中壁管两种，SBRSM带胶中壁管采用优质聚烯烃材料和环保热熔胶层复合而成，RSFRM不带胶中壁管采用优质聚烯烃材料精心加工而成，广泛适用于低压电力的绝缘保护和机械应变缓冲与房磨损保护，产品具有绝缘、密封防水(带胶中壁)、柔软、外层自熄、环保等特点。

主要应用：

①低压电力电线、电缆的接头和终端的密封绝缘防护；

②电线、电缆和各种机械产品的抗挤压和防磨损；

③船用线缆的密封防护；

④管道防腐和密封；

⑤带胶中壁使用环保热熔胶，产品的绝缘性密封性可靠，适用于有RoHS指令要求的环境；

⑥其它需要密防护的场所。

产品使用范围：

①运行温度：-45℃～125℃

②收缩温度125℃

标准颜色：黑色(可订做其它颜色)