Integrally reinforced nozzle 2

[virata]

Hi everyone!

What operating/design condition does an "Integrally reinforced nozzle/opening" is used?

From what I've read, this type of opening is normally used in lethal, cyclic, and hydrogen services - correct me if i'm wrong, and why is that so? What are other operating conditions/procedure ( design temperature, nozzle thickness, welding type, etc.) that this nozzle holds?

Appreciatte all your thoughts and answer for this.

Thanks!

- V.

 

[SnTMan]

virata, an "Integrally reinforced nozzle/opening" is any design which has no added reinforcing element such as a pad added. It may or may not be full penetration welded. It may be inserted or set-on.

It generally is preferred in the services you mentioned for various reasons. The design perhaps contains no un-welded crevices, it can be more easily inspected in service, it may be radiographable, etc. depending on the exact configuration.

If you have Section VIII, Div 1 available, see the figs in UW-16. See also UW-16(c)(1).

Regards,

Mike

 

[MJCronin]

Virata,


"From what I've read, this type of opening is normally used in lethal, cyclic, and hydrogen services...."

??????????? Really ?

Could you give us the sources from which you read this information ??

 

[TomBarsh]

There is a specific definition of "integrally reinforced" in ASME Code, UG-37. And then there is the "informal, customary, jargon" definition.

The definition of the "F" factor, given in UG-37(a) refers to "integrally reinforced openings" and points us to UW-16(c)(1). Such an opening has (1) no separate reinforcing pad and (2) full penetration corner joint weld to the shell if required by UW-16 rules. Paragraph UW-16(c)(1) provides a good description of how openings may provide integral reinforcement by using shell insert plates, or by using a nozzle neck that is forged with barrel of increased thickness, etc. Of course, simply going from, for example, schedule 40 pipe to XXS pipe may permit an inadequate design to pass without any additional reinforcing plate.

In "jargon", forged nozzles with a thin neck and a heavier barrel at the shell attachment are often referred to as "self reinforcing" or "integrally reinforced" nozzles. But as seen in UW-16(c)(1) these are not the only method of solving the problem that is answered by such forgings.

A related term that I have heard in the long-distant past, is "self-reinforcing nozzle". The point being that no reinforcing area was taken from the shell.