Pipeline span issue
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In the chemical process design manual, under the section on pipe spans, there are values for the basic spans of pipes inside and outside the equipment. What does it mean by \"inside the equipment\" and \"outside the equipment\"? ? ? ? ?
Inside the device refers to the area within the device itself, where the pipes used for various processes are located. Outside the device refers to the material transport pipes that connect different devices, which are usually installed in pipe racks and pipe supports
The pipe span is calculated based on the deflection of the pipes. The allowable deflection inside and outside the device differs, which is why the span is larger outside the device than inside it. What’s meant by \"inside\" and \"outside\" the device can be understood from this: at the boundaries between the interior and exterior of the device (usually at the junction between the internal and external pipe racks), there are rows of valve assemblies and measuring devices such as flow meters, and these elements help to distinguish between the inside and outside areas
The operating conditions of the pipes inside the device are more complex than those of the pipes outside, so the design span needs to be smaller.
I would like to ask: when several pipes are installed side by side, how should the span between the pipe supports be determined? Thank you for your answer
I never understood how the spacing is determined; the person above explained it
Compared to the original poster’s question, I’m more interested in knowing how to determine the span of pipelines
The calculation of pipe span is available in the chemical pipeline manual
When multiple pipes are supported together using a common support structure, the span of the support is determined based on the span of the pipe with the smallest diameter. Therefore, it is best to avoid arranging pipes with very different diameters side by side; however, if the difference in diameters is large, it is possible to use the same support structure for both the pipes of smaller diameter and those of larger diameter.
Within the plant refers to the area within the plant itself, mainly comprising the pipelines used for various processes, including the pipe racks inside the plant. Since various devices and reactors are connected within the unit, there is a high requirement for stable fluid flow within the pipes as well as for low deflection; therefore, the span of the same type of pipes in this unit is short. Outside the equipment refers to the material transport pipelines that connect various devices, generally including the plant’s pipe corridors and pipe supports. The external pipe gallery of the device is mainly used for transporting fluids, and it is acceptable if the pipes have some flexibility and bend slightly. The span of the pipes can be larger. The overhead clearance for pipes depends on the strength of the pipe material, the cross-sectional area of the pipe, the magnitude of external loads, the slope at which the pipes are laid, and the maximum allowable deflection of the pipes; in general, the design deflection for pipes is 15 mm ； The allowable deflection of the external pipes of the device can be appropriately increased to 38 mm. For an introduction to the spans inside and outside the device, see Teacher Song Keko’s \"Pressure Pipeline Design and Project Examples\" and Teacher Zhang Dejiang’s \"National Textbook for the Approval of Pressure Pipeline Designers\".