Discussion on expansion joint piping issues
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As shown in the diagram, a metal expansion joint is installed on the vertical pipe to compensate for displacements. A custom-made flange is welded to the pipe and connected to the bolts of the expansion joint’s flange. Due to piping requirements, a loose-flange is welded to the lower section of the pipe as well, to be connected to the bolts of the expansion joint’s flange. I’m not sure whether the specifications for loose flanges allow them to be connected to expansion joints; it’s possible that this could affect the expansion joint’s ability to compensate for displacements. I simulated the situation in my mind: once the loose flange is secured to the expansion joint with bolts, it becomes similar to a fixed flange that is welded in place, forming a single unit that together handles the stresses applied to the pipe. I’m a bit confused about this, so I hope everyone can discuss and provide answers
You may have overlooked the function of the four bolts on the pipe compensator (expansion joint). For reference.
The adjustment bolts of the expansion joint seem to have nothing to do with whether the expansion joint in question can be connected to a loose-flange
The four bolts that come with the expansion joint need to be loosened in order for it to function
There is no problem connecting it to the loop flange. The expansion joint must have some degree of movement, and after installation, the fixing bolts of the expansion joint must be removed.
This cannot be removed; the internal and external bolts of the screw must be set according to the forces of internal and external pressure. Typically, for the bolts of pipe compensators subjected to internal pressure, the bolt that is stretched the most needs to be locked, while the inner bolts should be left with a minimum remaining length and also locked. For reference.
It’s best not to confirm such a claim for now. Let’s see if it makes sense: this cannot be removed; the internal and external bolts of the screw need to be set according to the forces of internal and external pressure. Typically, for the bolts of pipe compensators subjected to internal pressure, the bolt that is stretched the most needs to be locked, while the inner bolts should be left with a minimum remaining length and also locked. For reference.
After adjustment, the installation is complete; the adjusting bolts need to be removed
This post was last edited by CHANGBAISHI on 2021-5-16 08:52. Interpretations may vary; regarding internal pressure pipe compensators, it is still best to lock the longest section in place. Oh, it’s better to seek technical advice from the manufacturer; proper use is very important.
I’m a bit confused after hearing you say that. First of all, what is an internal pressure pipeline? Are internal and external pressure pipes classified based on whether the medium inside the pipe is under positive or negative pressure? Secondly, are there corresponding standard guidelines for the installation and use of expansion joints in different operating conditions?