Compensation calculation for flat unstayed heads as per ASME B31.1

[laxmikant07]

Dear all

I want to perform compensation calculation for our one flat unstayed heads (opening required through header end plate) as per ASME B31.1?
I could not found any code reference in ASME B31.1. but i found in ASME Sec. 1,compensation calculation for flat unstayed heads as per PG - 35.2 but this one also limited the opening up to 0.5xhead diameters.but in our case the opening diameter is larger than 0.5x heads diameter.

I request to all for providing the valuable information & views.

 

[Fizza453]

Section I does not contain the rules for the opening compensation in flat unstayed heads that exceed one half the diameter of the flat head, see PG-35.3. Such openings shall be designed in accordance with PG-16.1 that gives you three options, first FEA, second the use of other codes and standards and books, third proof test.
I would suggest you use Appendix 14 of ASME Section VIII-1.

Nasir
Welding Engineer
DESCON ENGINEERING LIMITED
PAKISTAN

 

[GenB]

Fizza. Section VIII,1 design will not be acceptable in Sect I. / B31.1

 

[Fizza453]

Why not acceptable in Section I?
If your AI is agreed on the use of Section VIII-1 rules when those found missing in Section I, then no problem at all. Please see PG-16.1

Nasir
Welding Engineer
DESCON ENGINEERING LIMITED
PAKISTAN

 

[laxmikant07]

Dear All,

Please provide some other reference related to ASME B31.1 or Sec. 1.

 

[kalmari]

ASME B31.1-2012 says in paragraph 104.4.1 as follows:
"104.4 Closures
104.4.1 General. Closures for power piping systems
shall meet the applicable requirements of this Code
and shall comply with the requirements described in
(A) or (B) below. Closures may be made
(A) by use of closure fittings, such as threaded or
welded plugs, caps, or blind flanges, manufactured in
accordance with standards listed in Table 126.1, and
used within the specified pressure–temperature ratings,
or
(B) in accordance with the rules contained in the
ASME Boiler and Pressure Vessel Code, Section I, Power
Boilers, PG-31, or Section VIII, Pressure Vessels,
Division 1, UG-34 and UW-13, ...."

So flat heads in B31.1-piping are designed either acc. to Section VIII-1 or Section I.
And like Fizza453 wrote using Appendix 14 of ASME Section VIII-1 is logical to follow for opening compensation in head.

 

[laxmikant07]

Dear fizza453,

If you have this referenced code Appendix 14 of ASME Section VIII-1, as mentioned in your answer, please provide me.
Actually in my company Section VIII not available.

 

[fegenbush]

laxmikant07,

The purchase price of applicable codes and standards is part of the cost of doing business. Please do not ask members of this forum to provide copyrighted information for commercial purposes.

 

[chicopee]

ASME section I is for Power Boilers ( Fired Pressure Vessel); Section VIII if for unfired pressure vessels; so you'll have to state the type of pressure vessel before you can get help from the responders. Another code is AMSE IV which is for heating boilers, also this has code design details. ASME B31.1 is for power piping and will not have code design details about parts of pressure vessels. The ASME code that you should get is the one that was used during the construction of the pressure vessel.

 

[laxmikant07]

Dear All,

I required this calculation for our steam piping related to PC fired boiler. this piping designed by ASME B31.1 only.

 

[chicopee]

"I required this calculation for our steam piping related to PC fired boiler. this piping designed by ASME B31.1 only" If I remember correctly, in accordance with ASME/NB boiler codes the piping connected to the boiler will be part of a boiler component up to the first steam or water shutoff valve, so your piping in question will not be part of ASME B31.1. Only after the shutoff valve will the piping be part of ASME/NB B31.1.

 

[Fizza453]

see PG-58 OF ASME SECTION I FOR FURTHER DETAILS

Nasir
Welding Engineer
DESCON ENGINEERING LIMITED
PAKISTAN