Number of bolt in a bolted flanged connection
Number of bolt in a bolted flanged connection
(OP)
Hi
Can you help with this,
I used appendix Y of ASME VIII to calculate total required cross-sectional area of bolts of a bolted flanged connections. But I don’t how can I calcule the number of bolts or determine their size.
Thank you in advance
Can you help with this,
I used appendix Y of ASME VIII to calculate total required cross-sectional area of bolts of a bolted flanged connections. But I don’t how can I calcule the number of bolts or determine their size.
Thank you in advance





RE: Number of bolt in a bolted flanged connection
The number and size of bolts must be selected for two conditions:
1) Gasket Seating
2) Operating Loads
RE: Number of bolt in a bolted flanged connection
Determine the bolt circle from flange geometry.
Check if you can get enough bolts on the circle to satisfy the required area. Often good practice to add four (or more) bolts.
If minimum bolt spacing is not met, increase the bolt size, bolt circle and have another go...
(Hint - if you cannot get enough bolts of a given diameter on the circle, decreasing the bolt size will not work)
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: Number of bolt in a bolted flanged connection
Your question sounds a lot like a School home work assignment.
- Why are you trying to design your own Flanges?
- Don't you know that Flanges of all sizes and pressure ratings are already available on the market?
- Don't you know that all of the dimensional data for these Flanges (and the matching Bolts) is available on the internet?
- Don't you know that your Flange must match up to other flanged objects (Valves, Strainers, Pumps, Filters, Vessel Nozzles, Instruments, etc) that already come with the industry standard Flanges?
- Don't you know the designing and using custom flanges on a system will raise the cost of the project?
Sometimes its possible to do all the right things and still get bad results
RE: Number of bolt in a bolted flanged connection
RE: Number of bolt in a bolted flanged connection
see: http://pipingdesigners.com/contents/blog/130-blog-...
Sometimes its possible to do all the right things and still get bad results
RE: Number of bolt in a bolted flanged connection
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: Number of bolt in a bolted flanged connection
RE: Number of bolt in a bolted flanged connection
If so he (or she) did not make the question very clear.
Sometimes its possible to do all the right things and still get bad results
RE: Number of bolt in a bolted flanged connection
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: Number of bolt in a bolted flanged connection
RE: Number of bolt in a bolted flanged connection
As for custom made flanges as a Piper I tend not to see much of these even on connected equipment unless the size/rating is outwith ASME B16.5/B16.47 and in the event that the equipment flange is custom made the vendor will be asked to provide counter flange along with calculations.
RE: Number of bolt in a bolted flanged connection
I think the method is first to assume size and no of bolts,thus know the total actual c/s area, Ab.now calculate the total required c/s area Am = Wm1/Sb.For safe design Ab>Am.If its less we can increase no of bolts and size.
As others pointed out,there is a minimum spacing reqd between bolts.but in ASME i didnt see any condition like this.If you find please let me know.