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[分享] 酚醛泡沫管托与木、硅酸钙管托的对比分析

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之前福建天利|你还在用木管托吗?英国标准《BS5970-2012》 已禁止使用木管托 提到,《BS 5970-2012》标准已经明确说明:木管托不应被使用(“Wooden pipe supports should not be used”)。那么我们应该采用什么管托呢?各种管托有什么优缺点呢?请看下面这篇文章的分析。后面有英文原文。





保温(冷)管托概述


什么是保温(冷)管托?
保温(冷)管托位于管道本身和支架之间,以保持热性能。保温(冷)管托的主要类型之一-酚醛泡沫,能够有效阻止热传递,以减少热量损失和提高能量利用率。


你为什么需要它们?
保温(冷)管托将管道与支架隔离,以限制热传递和热(冷)桥产生。它还必须有较好的蒸汽阻隔能力。


保温(冷)管托的主要类型有哪些?
主要有三种主要类型的绝热管托:
木材 - 这是绝缘管道支撑最传统的方法。
酚醛泡沫 - 这已成为绝热管道支架的首选方法。
硅酸钙 - 主要用于极高温度。


木管托概述:
长期以来,木块是保温(冷)管托的首选材料。然而,近年来,木管托的使用已经减少。这可能是由于新的英国绝热管支架标准BS5970:2012,现在认为“不应使用木管托”。
这是由于木管托不能避免管道外部和管道之间产生热(冷)桥,所以容易形产生冷凝,并且没有办法阻止水分渗透。

酚醛泡沫管道保温(冷)概述:
酚醛泡沫是木块的一种非常有效的替代品,并迅速成为首选的管托材料




通过对管托位置进行热分析,可以看出,在低温热水系统上,使用酚醛泡沫管托可以比使用木管托减少高达10倍的热量损失。这是由于在低于环境温度的管道系统上,酚醛泡沫有很好的保持蒸汽阻隔和防止热传递能力。

由于更低的导热系数(更好的保温隔热性能),酚醛泡沫比木材、硅酸钙或泡沫玻璃能更好降低能耗、节约成本。



下图显示了(从左到右)酚醛泡沫管托,带橡胶内衬的金属支(吊)架,金属支(吊)架直接与管道连接,木管托的热损失率。





硅酸钙管托概述:
通常,在管道温度超过120℃(250°F)的地方使用硅酸钙绝热材料。因此,在化工厂、炼油厂和蒸汽发电厂等这些地方经常见到这种绝热材料。

保温(冷)管托是否有规定?
如前所述,英国标准 - BS5970-于2012年更新,这是与管道工程及其他工业设施的保温隔热相关的操作规范。2012年更新作了一些重大变化。
一个重大变化是,规范不再允许使用木管托,因为它们无法提供有效的蒸汽阻隔,并且具有较差的保温隔热性能。
此外,该标准建议固定在支架上的管托与管道上的绝热材料相同(或兼容)。

酚醛泡沫保温(冷)管托的好处
酚醛泡沫管保温(冷)管托经过测试,可以与无内衬支架及管道保温隔热材料兼容。我们的管托材料由高密度酚醛泡沫制成,具有极佳的保温隔热性能。它们不含氟氯化碳和氟氯烃,归类为零ODP(臭氧消耗产品)。为了保证酚醛泡沫的技术性能,每批产品都会按照ISO 9001:2015进行测试。
除此之外,酚醛泡沫还可以增加特殊的涂层,可以消除铜管道管道腐蚀的任何可能性。另外采用阶梯式的搭接方法,可以确保气密性和准确安装。








因此,我们建议使用酚醛泡沫来作为新标准后的木管托替代品,因为它具有极佳的保温隔热性能及其他综合性能。





英文原文:




An overview of insulated pipe supports





What are insulated pipe supports?

Insulated pipe supports sit in between the pipe itself and the pipe clamp or clips, to maintain thermal performance. One of the main types of insulated pipe supports, phenolic foam blocks, work to prevent thermal conduction which can result in heat loss and an increase in energy usage.




Why do you need them?

Insulated pipe supports isolate the pipework from the pipe clamp to limit heat transfer and thermal bridging. It also allows for a continuous vapour barrier to be carried through the support system.




What are the main types of insulated pipe supports?



There are three main types of insulated pipe supports:


  1. Wood – this is the most traditional method of insulating pipe supports.

  2. Phenolic – this has become the preferred method of insulating pipe supports.

  3. Calcium silicate – this is mainly used in extremely high temperatures.



Wood pipe insulation supports overview:

Wood blocks were the preferred material for insulating supports for a long time. In recent years, however, the use of wooden pipe support inserts has dwindled. This is likely due to the updated British Standard for insulated pipe supports, BS5970:2012 which now gives the view that “wooden pipe supports should not be used”.
Wood blocks do not offer a reasonable thermal bridge between the outer works and the pipe. There is an increased risk of condensation forming on wooden blocks and they are ineffective at maintaining vapour barriers.



Phenolic foam pipe insulation overview:

Phenolic foam pipe insulation blocks are a very effective alternative to wood blocks, and have rapidly become the number one preferred insulated pipe support material
Independent thermal analysis has shown that the use of phenolic insulated pipe support inserts can reduce heat loss through the supports of +75°C LTHW systems by up to 10x when compared to wood block inserts. This is in addition to the benefits of phenolic in maintaining the vapour barrier and limiting heat gain on systems operating below ambient temperature.
Phenolic insulation is also much more cost effective than wood, calcium silicate or foam glass alternatives due to a higher insulation value.
The image below demonstrates the rate of heat loss on (from left to right) phenolic pipe support, a rubber lined clip fixed to pipe, a metal clip fixed to pipe, wood block pipe support.





Calcium silicate pipe insulation overview:
Typically, calcium silicate insulation is used where pipe temperatures exceed 250°F. Therefore, the usual places you’ll find this type of insulation include chemical plants, refineries, and steam electric power plants.



Are there any regulations for insulated pipe supports?

As previously mentioned, there is a British Standard – BS5970 – which was updated in 2012. This is a code of practice relating to the thermal insulation of pipework, ductwork, associated equipment and other industrial installations. The 2012 update included a few significant changes.
One change being that the code of practice no longer permits the use of wooden block pipe supports due to them providing an ineffective vapour barrier and having poorer thermal properties than the alternatives.  
In addition, the standard recommends that the pipe support bracket being fixed over the load bearing insulation is of the same material (or compatible with) the insulation on the pipe.



The benefits of phenolic foam insulated pipe supports

Phenolic foam pipe insulation supports are tested and guaranteed compatible with our main unlined clamp ranges . Our blocks are made from high-density phenolic foam with the best available thermal insulation properties. They are CFC and HCFC free and classified as Zero ODP (ozone depletion products). To guarantee the technical properties of our phenolic, each batch is also tested in accordance with ISO 9001:2015.
In addition to this,phenolic foam have a special bore coating, which eradicates any possibility of pipe corrosion on copper pipes. They are also manufactured with stepped joint faces to ensure vapour seal and accurate placement.




We would recommend the use of phenolic foam over the alternatives as it has the best insulation value.


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酚醛泡沫防火保温隔热材料,酚醛保温管壳、托
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只看该作者 沙发  发表于: 07-18
保温托架的使用就是防止冷桥的产生,形成温变影响使用效果,上述技术分享很好,中英文对照,做的细心,让不懂英文的技术人员容易了解国外保温行业的一些动态,有利于我们国家当今保温材料应用和施工的技术进步,谢谢您的技术文章分享。张工。
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只看该作者 板凳  发表于: 07-19
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张作华:保温托架的使用就是防止冷桥的产生,形成温变影响使用效果,上述技术分享很好,中英文对照,做的细心,让不懂英文的技术人员容易了解国外保温行业的一些动态,有利于我们国家当今保温材料应用和施工的技术进步,谢谢您的技术文章分享。张工。 (2019-07-18 20:33) 

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酚醛泡沫防火保温隔热材料,酚醛保温管壳、托