Issues with calculating flanges in SW6
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This post was last edited by feng elegant on 2017-10-12 at 11:42. When using SW6 to perform calculations for custom flanges, the error \"Bolt spacing is greater than the maximum bolt spacing; verification failed\" occurs, but the stress verification passes. In such a case, can the flange be used? Is it still necessary to increase the number of bolts?
Why not increase the number of bolts? The standards specify it; follow the standards. If the number of bolts is reduced, it will inevitably lead to an excessive bolt spacing; even if the stress checks pass, leakage can still occur in the seal. In this case, the standard specifications are sufficient. However, when using SW6 for calculations, there is a situation in which standard equipment flanges according to NB/T47020 are employed, resulting in bolt spacing that does not meet the requirements; such a situation can be ignored directly
Flanges designed for quick disassembly have too many bolts, failing to achieve the purpose of quick disassembly
Can it be ignored directly? Is there any evidence?
Standard flanges are used, so calculation according to GB150 is not required
Should the manhole be opened soon? If it is a quick-opening manhole, use the standard manhole specifications; try to avoid custom designs. For non-standard quick-opening blind flanges, one can refer to the standard SYT 0556-2010 \"Technical Specifications for Quick-Opening Blind Flanges\". However, this standard specifies that \"the main pressure-bearing components of quick-opening blind flanges should be subjected to stress analysis using the finite element method.\" Therefore, in such cases, analysis and design are necessary; conventional design methods are not sufficient
If your equipment does not fall into a specific category and is not used with lethal media, you can refer to the ASME standard flange calculations, where the bolt spacing is not mandatory. However, there is a gap between theoretical calculations and practical applications; using too few bolts can lead to uneven stress distribution on the gaskets, increasing the risk of leakage
If there are too few bolts, there will be no seal; if there are too many, the flange has to be thickened, hahaha