EN13445 Flanges

[CobusvanJ]

Extract from EN13445-3 11.4.1: "Circular bolted flanged connections, either sealed with a gasket or seal welded, used in the construction of vessels to this standard shall conform to either: a) an appropriate European Standard for pipework flanges, and the requirements of 11.4.2; or b) the requirements for bolted flanged connections specified in this clause; or c) the alternative rules in Annex G."

Is it acceptable to use ASME B16.5 flanges for EN13445 vessels?

 

[roca]

I have seen an end users specification who has plants and refineries in Europe and who has a spec that gives supplements/ammendments to EN13445.
One of these is that ASME B16.5 and 16.47 flanges shall be used.
So it must be allowed.

Isn't there an EN 1759 which is equivalent to ASME standard flanges?

 

[TomBarsh]

roca, It is interesting that the spec says B16.5 flanges "shall" be used, and not "may" be used.

Here is a related question I hope someone may answer. ASME B16.5-2003 provides ratings and dimensions in metric units, US Customary units have been relegated to Annex F. But bolt sizes are still specified in US units as "inches". For example, see Table 10 (page 78), bolt size for a 24" Class 300 flange is 1.5".

For vessels constructed in Europe, or intended for installation in Europe under PED, would the B16.5 flanges be installed with bolts in "inch" sizes or metric? I cannot imagine the former. But the latter leads to conversion problems.

 

[roca]

"shall" be used is obviously so that the all the vessels on the whole plant use the same flange standard. This particular company wants ASME flanges all round. Have you ever seen a plant with a mix of ASME, DIN and API flanges? It would be a piping nightmare.