Nozzle set-on or set-in 2

[Spoonful]

Hi All,
Here I have got a question; it might be stupid question or not an issue at all.
Nozzle opening on the vessel, Can the nozzle be set on rather than set in?
We have always used nozzle to be set in. The reason is that not only we can have a full penetration weld but also that the weld the across the whole thickness of the shell, If we use nozzle to be set on, we can still have a full penetration weld, but the entire weld would be only on the surface of the shell, if there is any lamination in the shell. The whole weld or the nozzle could tear off at the lamination.

The reason of my concerning is, sometime we need to consider using weldolet instead of con pads. But weldolet are normally set on. Dose the PV code state anything in regarding with these nozzle Set on or Set in issue? AS1210 dose allow to use set on nozzle attachment method. Dose ASME had anything to say about this? Or am I just over concerned?

Could anyone give some hints, Thanks in advance.

 

[metengr]

No. Selection of nozzle attachment is an engineering process detail and is left up to the designer to choose among nozzle attachment options in ASME B&PV Code.

 

[Bobfromoh]

I don't think weldolets are supported by the pressure vessel code.They are a piping component (B31.*). See table U-3 in the asme pressure vessel code, Div. 1. Weldolets are not listed there.

 

[Fizza453]

Bobfromoh is correct in the sence that weldolets are not listed in table U-3. These are not Standard ASME Pressure Parts. These are accepted under the provisions of UG-11 as manufacturer's standard pressure parts.

Spoonful: As far as attachment details are concerned, you may use any detail of Figure UW-16 provided the rules of UW-16, UW-15 are satisfied.Process design is another concern regarding set on or set in, Section VIII keeps silent on this issue.




Nasir
Welding Engineer
DESCON ENGINEERING LIMITED
PAKISTAN

 

[Spoonful]

Thanks all for the comments

 

[Spoonful]

Fizza453,

if these weldolet are accepted by UG-11 as manufacturer's standard pressure parts, therefore it still can be used by the code?

Thanks

 

[Fizza453]

Spoonful,

Yes weldolets are accepted as manufacturer's standard pressures parts and are used in Section VIII construction under UG-11 provisions.
We procure these fittings from FVC (Forge vessel connection) that is a renowned manufacturer of such sort of fittings.


Nasir
Welding Engineer
DESCON ENGINEERING LIMITED
PAKISTAN