How are the calculation formulas for shellless coil heat exchangers derived?
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The outer diameter of the inner tube 45 in the shell-and-tube heat exchanger is as follows; the outer diameter of the shell 108 has a design pressure of 1 MPa, with a corrosion allowance of 2 mm. According to the new pressure vessel regulations, this equipment falls under Category I pressure vessels, and therefore a calculation document is required. However, SW06 does not provide the necessary calculations – so how should this calculation document be prepared? Does this shell-and-tube heat exchanger also need to meet the minimum wall thickness requirements specified in GB150?
Why doesn’t SW6 perform the calculation? Software is dead; people are alive. I would do it this way: can I treat it as a jacketed vessel? If not, I’ll calculate the internal pressure, external pressure, or pressure difference separately for the pressure-bearing components, and then put all the calculations together in a report. You can also use EXCEL to create your own formulas for calculations, such as those for temperature difference stress. In my opinion, it is not necessary to meet the minimum thickness requirements specified in GB150/GB151, as these requirements are intended for purposes such as lifting, transportation, and assembly. Casing heat exchangers generally do not need to take these factors into account.
I prepared an Excel calculation sheet myself, but it was rejected during review on the grounds that the calculation procedure had not been verified. I’m so frustrated!
Can this be used in a class? The diameter needs to be greater than 150 mm.
Since the diameter is less than 150, the minimum wall thickness does not need to meet the 150 requirement. When the nominal diameter of the inner cylinder is greater than 100, SW6 can be used to prepare the calculation sheet for jacketed vessels; however, when the nominal diameter of the inner cylinder is less than 100, it is not possible to generate a SW6 calculation sheet. This issue was raised during the last training session, but no solution was found.