What is the min. size cladded inconel #1500 ball valve

[ericwals]

What is the minimum size cladded of inconel #1500 ball valves. For a project we are using full Duplex SS ball valve for #1500 and #2500lbs.
The customer wants a price reduction and is asking for CS with Inconel 625 3mm cladding.
Is this an economic solution?
Can somebody advice?

Thanks Eric

 

[JLSeagull]

I have never bought a cladded valve. I am using Hastelloy C-276 for NPS 1/8 valves and would buy them in duplex, Inconel 625, Incoloy 825 or whatever is required. The same applies to thermowell material etc.

 

[gerhardl]

I have seen supplied to the North Sea (platforms, not submerged) 8 inch 1500lbs cladded with inconel, with satisfying economic lifetime, but:

cladded valves are a highly specialized process, and only a few top companies are available to do this with good results. The process requires very thourough test and control procedures.

If everything is done properly, this could be an economic advantage, but there is always a 'but'....

 

[mqas]

Eric,

Based on my experience, there is a cost justification for CS valves clad with CRA against solid stainless steel or Ni Alloy valves. The exact size when this becomes economical really depends on the valve design and on the internal processes that are involved. Bearing in mind that for clad valves you will have additional machining operations and possibly PWHT and NDE to consider.

Having said that, I have found cost justification at 4" / 6" valves for 3 piece trunnion mounted ball valves.

 

[ericwals]

I got feed back from a valve expert. He said Incoloy 625 cladding can be applied on 3" and larger ball valves.
The body will be internally cladded and the stem and ball full duplex SS.

We are bidding on a project with around 800pcs 2,3,4inch #1500/2500 ball valves.

 

[mqas]

Eric,

It really depends on the design and the problem areas are the stem and trunnion bores. On smaller valves these diameters can be quite small and require specialised welding equipment for accessing the bores. You could sleeve these bores wtih CRA and then weld into place which would allow you accomodate much smaller valves but as I said, the additional processing may make it uneconomical.

 

[Nilsoni]

For 800pcs even a 2-1/16" class 1500, 2-piece side entry ball valve can be cladded. For the ball material the size have to be 6"-8" or larger to be eqonomical.