Can anyone please help me with the following: 1. What are steam rings?

Steam Rings in Hydrogen Service
Wow! you are going to really test my long term memory on this one.

What are steam rings? A "Steam Ring" is a device shaped and made to fit around the outside of a completed flange joint. It fits on the outside diameter of the two flanged and with gasket seals it forms a chamber that coexists with the raised face gap between the two flanges.

I was told they are meant for leaks. Yes it was created to prevent or reduce gasket leaks at flanged joints in Hydrogen systems.

How do they work? The ring is made with a connection to which Steam is piped. The pressure of the steam is selected to be at or above the pressure of the Hydrogen that is inside the pipe line. The steam in the "Steam Ring" provides a positive pressure on the outside of the flange joint and therefore reduces the probability of Hydrogen leaking out.

What are the specific points to remember while designing them? You heed to get a good seal and the "Ring" must be designed to take the pressure of the steam.

I'll suppose that there's no specific standard in this case. There may be a Standard but I do not know what it is.It might be in the ASME B16.??? category.

I do not know who makes them today. You will need to do some research.

Thanks all.

Nice to know something new.

Just curiuos about what is the criteria for using steam rings for the pipes in hydrogen service.

I am modelling some 3" and 4" pipe size, in Hydrogen service (flange rating 900lbs), but the P&IDs not provide
any requirement of steam rings.

Cheers

aubajwa,
You asked:
"what is the criteria for using steam rings for the pipes in hydrogen service?"
The criteria for adding "Steam Rings" is there is a leak.

"I am modeling some 3" and 4" pipe size, in Hydrogen service (flange rating 900lbs),"
I assume you are using PDS or PDMS or CADWorx or some other CAD system. These systems do not cover all situations that occur in Piping Engineering and Design or Maintenance. So there is most likely no established symbolgy.

"but the P&IDs not provide any requirement of steam rings."
I also doubt that the ISA Standards for P&IDs have symbols for this either. Most Steam Rings are added by plant maintenance after the plant is running when they suspect or find a leak.

Thanks Jop,

Alright I understand. During the plant operation if they find some leaks in hydrogen class service (i hope in any pressurized service), the solution normally comes to steam ring.

Now normally 'quality' pipers tend to be aware of possible problems during plant operation and their solutions, and tend to provide facility for those during the layout e.g

- maintaining a std. distances b/w lines, if there is a need of any flanged item in future.
- providing flg. spools to allow for removal of gate valves and check valves. specially near to rotating equipment

similarly for what pressure rating a piper should be aware of any possible requirements of steam rings b/c of flg. leakage (in case).
and How can a piper facilitate this requirement during initial piping layout.

Regards