Standard life is just a reference value
JB/T 12235-2015 stipulates that the design life of non-metallic expansion joints is usually 10-15 years, but there are many projects that can last for three to five years in actual projects. The life span of this thing is never determined by the manufacturer. The key depends on how you use it. Take the desulfurization flue of power plant as an example. With corrosive gas and high temperature, non-metallic expansion joints (fabric fiber expansion joints) can last for three years, even if they are high-quality products. On the other hand, it is not unusual to use it for more than ten years in clean ventilation ducts. You ask about the lifespan of non-metallic compensators? The standard is the standard, the reality is the reality, don't take the national standard as a life-saving talisman.
Material determines the upper limit, working condition determines the lower limit
Rubber compensator, rubber PTFE compensator, fabric fiber expansion joint-different names, different lives. Rubber is afraid of aging, PTFE is afraid of high temperature, and fabric fiber is wear-resistant but afraid of acid and alkali. Two days ago, I met a customer from a cement factory, who chose the metal corrugated expansion joint in the cement industry. It was not said that the non-metal was cheap and had to be replaced. As a result, the high-temperature dust was washed and it leaked in three months. It's not that non-metals can't be used, you have to find out its temper: when the temperature exceeds 200℃, it begins to lose its life, and the particulate matter in the medium is a life reminder. Alas, in the final analysis, the material just gives you a theoretical ceiling, and the working condition is the real floor.
Installation and maintenance is the real watershed
Whether you put it right or not, the difference is three to five times the life span. There are three common pits: First, the guide tube is installed backwards, and the airflow directly washes the compensation layer; Second, the tie rod nut is adjusted too tightly, which limits the displacement compensation and forcibly cracks the material; Third, there is no pre-deformation left during installation, cold deadlift, and it will explode as soon as it is turned on. You asked how to adjust the expansion joint tie rod? The manufacturer's manual is clearly written, but the on-site master can save trouble and screw it to death directly. No matter how good a non-metallic compensator is, it can't handle this. Is that the truth? If the installation and maintenance are not in place, no matter how good the material is, it will be in vain.
When should I change? Don't wait for it to be completely scrapped
Leaks, surface hardening, fabric delamination, noticeable distortion-don't hesitate to show any of them. Especially the non-metallic expansion joints near the desulfurization flue gas baffle doors corrode faster than you think. It is recommended to check at least once a year, focusing on flange joints and fabric overlap seams. Don't expect it to hold up to fatigue cracks like metal expansion joints, nonmetallic failures are often sudden and more expensive to repair than replace. What about that? Regular inspections are much more cost-effective than mending leaks afterwards.