I have some questions regarding natural compensation in Π-shaped bends
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Regarding pipe bends, what are the requirements for the value A shown in this diagram? What are the requirements for the bend arm length B? Are there any relevant standards or books that explain this issue? What is the relationship between the values A and B of the pipe bend and the pipe diameter? Also, what are the requirements for placing the guiding supports and fixing supports near the pipe bend? I would appreciate some guidance from experts. I observed on-site that some elbow fittings collapsed at the bend points, so I’m wondering what considerations should be taken into account when designing such elbow fittings
There are also the requirements for setting L-shaped and Z-shaped bends; I hope you can help answer those as well
The A value is generally 32-40 DN, while the B and C values are determined based on actual conditions and stress analysis
For π-shaped or square compensation structures, the value of B determines the compensation capability of such structures; the higher the value of B, the greater the compensation capability. The setting of the fixing points is related to the thermal expansion of the pipeline; the greater the straight-line distance between the two fixing points, the greater the thermal expansion of the pipeline. It is not certain regarding the thermal elongation; it should not exceed 250 mm, and it is recommended to keep it below 150 mm. According to the petrochemical standards, the A value is required to be 32–40 DN; the relevant supports must be guide supports, and the spacing between these guide supports is specified in the petrochemical standards. The collapse at the pipe end observed on site is caused by an excessively high ABC value; in simple terms, that section of the pipe is too heavy. It is necessary to learn about the knowledge of pipe span here. In short, I recommend that you consult the \"Piping Design Manual\" to learn more; it provides detailed explanations on the three common methods of natural compensation that you are interested in.
Original poster, you can consult documents such as the \"Piping Systems Manual\" and the \"Heating Piping Design Manual\", look through existing posts on forums, and ask your colleagues – you’ll find out after doing a quick calculation
The fourth floor is very detailed! At the π-bend, install sliding supports as well; if possible, apply pre-cold tensioning