Things related to pipes, how to match them – pipes, flanges, gaskets, bolts, tees, etc., the relevant standards, bolts...
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This post was last edited by 328104062 on 2016-12-27 at 23:14. As the title suggests, there are many standards for pipes, such as HG20592-20653 (including European and American standards), but none of them can help me solve my current problem: determining the appropriate length of bolts. For two WNRF flanges of DN20 CL300 with an intermediate gasket (a regular wound gasket), what size of fully threaded bolts should be used? HG20615 (the table on page 269) specifies that 4 bolts of M16 size are required. However, the specifications and dimensions of these bolts are to be determined according to HG20634 and HG20635; yet there is no table providing corresponding values. 1. What size of fully threaded bolts are needed for two WNRF flanges of DN20 CL300 with an intermediate gasket (a regular wound gasket)? Should it be 4 bolts of M16*60 or M16*75 size? Where can I find the specific standards and tables related to this? Or can it only be calculated based on various regulations, such as bolt length = 2 flanges + gasket + two nuts + 5~10mm? 2. The design institute has regulations regarding the grades of pipeline materials; these regulations specify which pipeline components should be used for pipelines at different pressure levels, in accordance with the relevant standards for the media involved. But how should the length of bolts be determined? I guess it should be manually calculated and then organized. 3. Please help me improve this table; thanks, extra points will be given. Standards for flange gaskets, standard fasteners (bolts), standard pipe fittings, pipes, elbows, tees; standards for valves, blind flanges; standards for selecting appropriate materials; standards for non-destructive testing of pipes. Standards for pressure testing of pipes, regardless of whether they follow American or European standards; acceptance criteria for pressure pipes, also regardless of whether they follow American or European standards. Complementary to American standards: HG20615, SH3403, HG20634 (bolt length), SH3408, ASME16.34, HG/T 21547, SH3059, HG20635, HG20592-20653; SH3406, SH3407, SH3404, SH3409, SH/T 3129, ASME16.5, SH/T3405, SH3410, ASME16.9, ASME16.11, SH3405. Complementary to European standards: HG20592, HG20613 (bolt length), HG20592-20653
It’s better to combine things with practical considerations, as blind plates need to be installed between some flanges; in such cases, the bolts may need to be longer. It’s best to take into account actual production conditions when establishing standards.
Basically, the length of the bolt can be determined based on the flange standards and the type of sealing surface. It is possible to look up the bolt standards corresponding to the flange in order to determine the bolt length; the lengths specified in these standards can be used directly. If flanges in accordance with the HG/T20592 standard are used, the bolt lengths can be found in the HG/T20613 standard; this standard contains tables classified by the nominal pressure of the flanges and the type of connection, on pages P192 to P207. For flanges specified in the standards HG/T20615 and HG/T20623, refer to standard HG/T20634, pages P440–P449. For flanges of type DN WNRF CL300, table 5.0.6-5 shows that the length LZR of the RF-connected flange bolts for DN20 is 70 mm.
The above is the length without components such as blind plates in the middle of the flange; if blind plates are used, the length must be increased further depending on the thickness of those blind plates.