CE marking - Pressure Vessel Supporting Structure

[jomocas]

Hi there,

I would like to know if the supporting structure of a pressure vessel can be included in the CE marking of the pressure vessel itself (by including it in the design), or if there is no way to include it.

In case it can be included, does the structure need to be permanently joined (ie welding) to the vessel? Or can it be bolted to a part of the vessel?

In case it cannot be included, according to which norm/directive/regulation can we CE mark the supporting structure?

Looking forward to your kind reply.

With best regards,

 

[Vikko]

This is a phylosophical question in my opinion.

The short answer is no. Because the PED (2014/68/EU) is relevant to Pressure Equipment. For structures there are many other kind of rules and laws which I don't know. For the PED the welding of the supporting structure is not so important if you do not weld directly on a pressure bearing part, like the shell for example.

But in case the supporting structure is part of the pressure equipment itself, the rating plate with CE stamp can be applied and it covers all of the equipment. Consider a small pressure vessel, where the support structure is very simple frame, I expect to be all the same product with the its supports. This is the same for any other product, also in a TV/computer/machine/motor/etc you can have some supporting structures, but when you can apply a law which covers all of it, you do not have to also look at civile engineering laws.

Some complex calculations can be done following the rules in EN 13445-3 for example:
16.8 Horizontal vessels on saddle supports
16.9 Horizontal vessels on ring supports
16.10 Vertical vessels on bracket supports
16.11 Vertical vessels with supporting legs
16.12 Vertical vessels with skirts
16.13 Vertical vessels with ring supports
16.14 Global loads

For example you have to consider what says EN 13445-3 / 16.14.9 Wind and earthquake loads:
"Calculation of wind loadings shall be carried out in the manner recommended for structures in the territory in which the vessel is to operate."

So in more complex cases, where the supporting structure is part of the building or the foundations, I think that the civil engineers should better know what is best to do.

 

[KVdA]

The CE marking is for the pressure equipment. Attached are the supports ho will influence shell stress. The nobo will/should focus on this rather than checking the complete support design itself. Mind you that this line is sometimes difficult to draw.
The same phylosophy should apply for “bolted” supports.

 

[KevinNZ]

In New Zealand the supporting structures and foundations must be signed off by a certified civil engineer (NZ legal requirement). The loading calculations (EQ, wind) and support design must follow local civil design codes/standards (PN19). The pressure equipment inspector will not sign off until they see the civil certification.

The support attachment the vessel shell is a mechanical design issue and has 3rd party design verification as part of the vessel design.

(We do have problems with the NZ civil design codes not corresponding well with the ASME vessel design assumptions. NZ civil design codes are not straight replacement for American civil design codes.)