1. Those names of non-metallic expansion joints in the industry
You call it "non-metal compensator", he calls it "fabric compensator", and others call it "fiber expansion joint" and "rubber compensator". Two days ago, I met a customer, and when I came up, I asked, "How much is your expansion joint made of cloth?"-actually, they all said the same thing. There are so many aliases for non-metallic expansion joints: non-metallic compensator, fabric fiber expansion joint, rubber compensator, rubber PTFE compensator, rectangular non-metallic expansion joint... Just by looking at the names, you can easily think that these are products that can't be hit by eight poles. But in fact, they all fall into the category of "non-metallic expansion joints", but the materials and cross-sectional shapes are different, so the names are varied. To put it bluntly, these aliases are like nicknames, with different names, but they are all the same kind of things in their bones-flexible connectors used to absorb thermal displacement of pipes and reduce vibration and noise.
2. Structural differences behind aliases: fabric, rubber, PTFE
Why are there so many names? The core is that the material of the ring belt constituting the non-metallic expansion joint is different.
Most commonlyFabric fiber expansion joint(That is, the paragraph 14 in the product information of this site, officially named "non-metallic expansion joint (fabric fiber expansion joint)"), the loop belt is made of multi-layer fabric, silicone cloth and fluorine tape, with high temperature resistance and good flexibility, and is often used in flue gas pipelines. You say it carries five to six hundred degrees in the high-temperature flue, which is pretty common.
Whilerubber compensator(Article 9) The main body of the ring belt is rubber, which has greater elasticity, and is suitable for low-pressure and large displacement scenarios, such as the soft connection of the fan outlet. But temperature resistance... To be honest, rubber begins to age when it reaches above 150℃, which is incomparable to the temperature resistance of fabric fibers that can easily be thousands of degrees.
There is also a kind calledRubber PTFE compensator(Article 12), lining the rubber layer with PTFE, which combines corrosion resistance and flexibility-you can tell by the name that this thing is different from a pure rubber compensator. The medium in the desulfurization system contains acid, and the rubber can't bear the corrosion, but once the PTFE layer is put on, it is proper.
Rectangular non-metallic expansion joint(Article 10) is distinguished by shape and is used exclusively on square pipes or rectangular flue ducts. So don't get swept around by "alias", just look at the material and shape to get in the right seat. You can't have a round non-metallic expansion joint connect to a rectangular pipe, can you? You can't even fit it, can you?
Third, why does the same thing have different names? Standards and habits
From the perspective of national standards, JB/T 12235-2015 is collectively referred to as "non-metallic expansion joints", but there are various habits in the industry. Where are the roots? One is regional habit: many manufacturers in the north like to call it "compensator", while in the south, it is called "expansion joint" more. In fact, according to Article 14 of the question and answer of this site, the expansion joint and the compensator are the same thing, which is recognized by the national standard and industry consensus.
When used in boiler flue, it is called "flue compensator", and when used in fan outlet, it is called "fan soft connection". In addition, the registered trademarks and product names of different manufacturers are different-for example, our site takes "fabric fiber expansion joint" as the official name of non-metallic expansion joint (Article 14), while "rectangular non-metallic expansion joint" has set up a separate portal (Article 10). Do you think it's messy or not? But the underlying logic is the same: absorbing thermal displacement, reducing vibration and noise. As long as the goal is achieved, you can call a cat or a dog.
4. How to choose the appropriate "alias" products according to the working conditions
When selecting, don't just look at the name, but also the parameters: medium temperature, pressure, corrosiveness and displacement. These things are hard currency.
In the case of high-temperature flue gas (> 300 DEG C), "fabric fiber expansion joint" or "non-metallic expansion joint" is preferably selected, and silicone gel cloth + ceramic fiber is used for the loop belt, and the temperature resistance can reach 1000 DEG C or more. If you install a rubber compensator on the kiln tail pipe in the cement industry, the picture is too beautiful to look at-it will be baked into slag in less than two months.
If it is a desulfurization system and the medium contains acid, then you have to use a "rubber PTFE compensator". The PTFE layer carries corrosion and the rubber layer carries displacement, which is the best of both worlds. For pipelines with normal temperature, low pressure and large displacement, it is most cost-effective to directly use "rubber compensator", which is cheap and easy to use, and the displacement can be more than 100mm.
Rectangular pipes must correspond to "rectangular non-metallic expansion joints". Don't use circular non-metallic expansion joints to make hard-the interface doesn't match. Don't forget the pressure in the working condition parameters. Non-metallic expansion joints are generally used in low-pressure environments (within 0.1MPa). If you install non-metallic joints on the steam pipeline, you are causing trouble for yourself.
5. Guide to avoiding pits: Don't be confused by aliases
A customer asked "Do you have a fabric compensator?" I said yes and sent itNon-metallic expansion joint (fabric fiber expansion joint)。 He asked again, "Is the compensator the same as the expansion joint?"- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - But don't think that all the things called "compensators" are non-metallic-metal corrugated expansion joints are often called "metal compensators", and their structures are completely different. They are stainless steel bellows, and the non-metallic ones are fabric belts. They can't be matched.
Is the loop band fabric or metal? Is it lined with PTFE? Rectangular or circular? The safest way: provide the working condition parameters (temperature, pressure, diameter, displacement) and let the manufacturer match them. Don't care if it is called Zhang San or Li Si, the one who can work is a good expansion joint. You say so, right?