Long Weld Neck on Hydrogen Service Reactor

( hmmmmmmm .......... maybe a response when I am logged on and not posting as Guest will have an effect)

So to repeat my previous answer:

Yes.

Thanks, but if it is contradicting with Licensor specification?

Well, as the two rules of customer service go.

1. The customer is always right.
2. If the customer is wrong, see Rule #1.

What is the reason you are wanting to go with a reinforcing pad? I suspect it is due to external loadings, because the main intent of long weld necks is to avoid/negate the requirement for a pad due to "area replacement". And if so, are you able to lower the external loadings?

Whooops

I accidentally signed in as my old alter-ego "Guest." that should have been posted by this username "XMech"

(it's a long, confusing story, so please don't ask)

Can you tell me is there any harm by using Rf pad for nozzles of reactors which is in hydrogen service.

None that I am aware of - we have a lot of them in our gas reform plant.

What I understand is that you donot want to go for LWN nozzle and use re-pad instead. The size of your nozzle is small if you consider pipe nozzle and as per code it may be exempt taking into consideration few clauses. Please check do you really require reinforcement requirement due to reinforcement area consideration.

If you need to provide re-pad due to nozzle loading, then my answer is "If client spec calls for self-reinforced nozzle... you cannot go for re-pad."

And to clarify one more thing... re-pad can be given in hydrogen service. It is only and only client requirement....

GA for you as always you hit the nail on the head with your responses and give the ASME back-up documentation as well.

My dear friend pipewelder, thank you very much for your nice compliments.

Dear Sir,

In a similar case, I have used 2" LWNRF over Dished end with RF pad in reactor, but our client have objection that for H2 service pad type arrangement does not stand guranttee for prolong use. I have used KCS material, with vent hole over pad and PWHT full.

Can you please give any reference where this time of arrangement working from long time. Also, if possible can you provide your mail ID so that other detail can be sent to you.

My understanding about hydrogen service is that hydrogen diffuses through metal and collects in trapped void spaces. If a pad is used, it must have vents (which the ASME Code requires anyway).