The thermal expansion displacement is large; is it possible to install 2 expansion joints on the pipeline?
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This post was last edited by FORREST_GUMP on 2017-10-23 09:31. As shown in the diagram, both the upper and lower devices have their ear mounts fixed to the platform. The operating pressure of the device pipes is 1.5 MPa, and the operating temperature is 200°C. There are vibration shocks in the intermediate pipes, and thermal expansion causes a compression of 20 mm in the pipe connecting the two devices; the diameter of this pipe is DN50. I checked the samples from several expansion joint manufacturers; the compression amount for a single DN50 expansion joint is less than 20 mm, and I don’t want to increase the diameter of the bellows ； May I ask the expert: Is it possible to install 2 expansion joints in adjacent positions along the pipeline? If it is possible to arrange it, can the flanges of the 2 expansion joints be directly connected with bolts? First, thank you, hero.
It is possible, but it is necessary to choose an expansion joint with a pressure of 1.5 MPa and a temperature of 200°C.
Thank you, hero. I am planning to install 2 expansion joints. I’m concerned that due to thermal expansion, the two joints might not be aligned, causing the pipeline to twist. Is such a possibility existing?
It’s possible, but expansion joints can absorb not only longitudinal variations but also lateral deviations as well, though to a lesser extent.
It can be modified by making cuts in the existing pipe, resulting in better concentricity.
Of course it’s possible, but why use expansion joints? Can’t just add two elbows?
The two devices are coaxial, one above the other; the material contains a large amount of crystals, so the connecting pipe in between can only be arranged vertically, with no bends allowed.
Thank you. Which is better: having two expansion joints placed next to each other, or having them located at both ends of the pipe?
Although expansion joints are easy to install, they are prone to breaking after all. Moreover, if there are crystals, they should also tend to accumulate at the expansion joints. If it is a new plant design and the storage tank below is not very large, its support can be changed to spring support.
Based on the characteristics of your materials, it is recommended to place them at both ends of the pipeline so that they can be removed in case of blockage.
Pay attention to the installation rules for your fixed supports and expansion joints: on straight pipelines, generally only one pipe expansion joint is installed between any two adjacent fixed supports. If two or more expansion joints are installed, uneven loading on these joints may occur due to differences in their stiffness or variations in the frictional forces of the guiding supports~~