Electric boiler according to ASME VIII-1 3

[Josep Maria Perdigo]

Can there be a very small completed electric boiler stamped only with U-stamp and the letters UB (special service), that is, without the E-stamp (ASME I)?

 

[IdanPV]

Hello Josep,

An electrical boiler consists of the pressure vessel and the electrical installation, Section I allows the constructing of pressure vessel according to Section VIII-1 alternatively, whereat the paragraphs PEB-3.1 through PEB-3.4 need to be met. Even if the pressure vessel is constructed according to VIII-1, the whole boiler is still Section I part, refer to Form P-2A Part I.

Even if the PV is constructed according to Section VIII-1, all other requirements (boiler external piping requirements included) stated in PEB Part and in General part of Section I must be followed.

I hope this is of assistance.

 

[Josep Maria Perdigo]

Thank you very much IdanPV.
Starting with ASME I, I also come to the conclusion that you present.
But, if we go directly to ASME VIII-1, U-1(g)(1), where it says "Unfired steam boilers shall be constructed in accordance with the rules of Section I or this Division [see UG-120(f), UG-150(d), and UW-2(c)]".
Unlike ASME I PEB-3 which limits the use of VIII-1 to the "boiler pressure vessel", I understand that VIII-1 U(1)(g) refers to the (completed) boiler, that is, the boiler with all the accessories that make it functional.
How about?

 

[IdanPV]

I assume this is a vessel in which steam is generated and withdrawn for external use.
And hence, it shall be constructed in accordance with Section I.
According to PEB-3, only the boiler pressure vessel may be constructed in accordance with VIII-1.
But the completed boiler (see Section I, PG-104.1) shall be certified to Section I.
It is my understanding that starting with Section I is the only option.

 

[Raul Villalba]

Sorry for the intrusion, but I don't quite see it clearly

According to my interpretation of ASME VIII-1 U-1(g), if it has an immersed heating element and the steam is used externally, it is considered an unfired steam boiler, see interpretation detail. Therefore, the sentence "Unfired steam boilers shall be constructed in accordance with the rules of Section I or this Division [see UG-120(f), UG-150(d), and UW-2(c)]" gives you two paths to certify the completed boiler: ASME I or ASME VIII-1, which uses ASME I for the security valve in UG-120(f).

Do you agree?

 

[IdanPV]

Hi,

No doubt about it. The boiler pressure vessel may be constructed in accordance with VIII-1.
The completed boiler, which includes the BEP shall be constructed per ASME I and a P-2A is needed.
Refer to:
[ul]
[li]PEB-3.4[/li]
[li]PEB-17.2[/li]
[li]PEB-18.3[/li]
[li]Interpretation Number BPV I-19-09[/li]
[/ul]

 

[Josep Maria Perdigo]

Hello again IdanPV. I thank you very much for your opinions.

In your last post, you exclusively use references from ASME I, to reach the conclusion that this Section should be used to manufacture the completed boiler. We already agreed on this in previous posts.

However, if from the beginning we approach the question exclusively from VIII-1, it is found that U-1(g)(1) is an alternative way to build the completed boiler, since U-1 does not refer to the "pressure vessel boiler ", but to the "boiler" itself.

On the other hand, the two options are also included in ASME I, Preamble, fourth paragraph from the end, which says: "Unfired steam boilers shall be constructed under the provisions of Section I or Section VIII."

 

[IdanPV]

What about the piping?
Pressure Relief Valve?
Hydrostatic Test?
Marking and MDR?

 

[Josep Maria Perdigo]

Hi IdanPV

What about the piping? The boiler is intended for hospital or pharmaceutical purposes. For boiler external piping that will apply ASME B31.3. In any case, it will be piping of very small size (<=1") and length (approximately 1.5 m).
Pressure Relief Valve?: UG-150(c) & (d)
Hydrostatic Test?: UG-99
Marking : UG-116, UG-116(a)(7) & (c)
and MDR? : UG-120, UG-120(d)(3)

What about any other questions not covered by ASME VIII-1: U-2(g)

 

[GD2]

OP,
It will be more appropriate the piping to be ASME B31.1. Go through the Scope definition in 100.1. The ASME B31.1 is not only for electric power generation plants but also used in industrial and constitutional heating and cooling plants.
What is the pressure, temperature design conditions of the piping?

GDD
Canada

 

[IdanPV]

It would be better if you directly contacted the Province or Jurisdiction where you would like to install this unfired steam boiler.

I would like to caution you that the laws or regulations at the point of installation may dictate the construction. Such laws or regulations should be reviewed to determine requirements that may be different or more restrictive than the Code.
Some applicable laws or regulations may require such unfired steam boiler to be constructed in accordance with Section I and with B31.1 piping.

I would be totally surprised if the Province or Jurisdiction will let you to construct the completed boiler in accordance with VIII-1.

 

[Josep Maria Perdigo]

Hello G2, thanks for your opinion.
The boiler's submerged electrical resistances have a total of 9 kW, MAWP is 6 barg, design temperature 175ºC, steam production approx. 12 kg/h.
The size of the pipe will possibly be 1/2" (and there is still more!). The length of the pipe will be really short: approximately 1.5 m, since the steam consuming equipment is right next to the boiler, forming a functional unit.
I have compared ASME B31.1 100.1 with ASME B31.3 300.1. and, in the latter I find, among others, one of the applications of the boiler: pharmaceutical industry. The other application is for hospitals.

IdanPV, thank you very much for your advice to consult local laws or regulations.
It surprises me that a legalization path established by ASME VIII-1 and ASME I (preamble) can meet so much opposition.

 

[IdanPV]

Out of curiosity, what will be the benefit of using VIII-1 instead of I in this case?
If you going to use VIII-1, you shall follow UG-16 so the minimum thickness for your boiler shall be 6mm, all butt welds shall be subject to full RT and your PRV shall be in accordance with I.
You may avoid the 6mm minimum thickness requirements (you will be limited to 5mm min.) and the RT requirements if you choose I.

 

[Josep Maria Perdigo]

Hello IdanPV

If you look for companies with the E Stamp in Europe, you will find practically none (Germany, Spain, France and Italy do not have any). In the USA, only three.

Manufacturers with the S or M stamp are aimed at fired boilers; They are not used to manufacturing austenitic stainless steel laboratory equipment with the demands of the pharmaceutical and hospital sectors (surface finishes, cleanability and asepsis).

Perhaps this is the reason why ASME VIII-1 offers the possibility of manufacturing the completed electric boiler,