Transform Valves SW in BW

[lolo78]

Hello Everybody,
I have a project in Russia and I learn today I can't weld any valves in SW (GostR do not accept SW).
My customer wants to make a reduction to transform the valves SW in BW.
Class of my valves is #2500.
What do you think about this ?

 

[JimCasey]

Carving on socketweld valves until they are profiled to be buttweld valves sounds like a baaaad idea.

You move the heat-affected zone much closer to the trim,
you get a valve with a non-code and probably nonuniform end-to-end dimension.

US code prohibits mahining flanges off to make weld-end valves. THis would fall under the same justification if not specifically addresed by the code.

And finally, if you modify the valves and there is ever an accident in the plant, the modified valves will draw a great deal of attention to you that you will not want. In the US we have lawyers. In Russia there is the Mafiya. Either way, you don't want the attention.

 

[lolo78]

Thanks JimCasey.

In fact, I learned they want to weld an indermediate piece made by themself, like a reduction, welded in full penetration.
One side (valve side) will be male with a shoulder at the external diameter of the valve and the other side like the pipe (I am waiting their drawing). Why not ?
Concerning the laws, they do what they want!!.....everytime !
I think that I should be far when the plant will be started. Fluid is Synthetis Gas.

 

[terje61]

Hello Lolo,

It looks like you are in doubt regarding the safety of the work they will do on your valves. I would therefore not accept it. It is your companies name that is on the valve. I advise to ship your valves back and make the intermediate piece yourselves. This way you can make sure that it is up to your standards.
Prompt action may even improve the relationship with your client.

Regards,
Terje

 

[onrush]

If the Client accepted it and there was no restriction for
end-to-end dimension,
I recommend you to make , if possible at site, the SW end into BW and attach the spool piece pipe to BW end to prevent the damage of valve gaskets and packing from the heat emission during welding.

Please note that the attachment welding between BW and spool piece shall be full-penetration and 100% RT may be mandatory.

 

[lolo78]

To terje61 : It's not easy, we are in shutdown during 50 days (I have never seen a long time like this before !!). Delivery time for valves is very long (I'm French), actually, about 3 or 4 months minimum.

To roby : All Ø are under or equal to 1"1/2

To onrush : My client proposed this. He is in charge of the drawing and the fabrication of this spool piece.
I will be on site on monday, I will see that.
I think they discovered that they are the Gost and another world .
Concerning the spool pieces, welds are full-penetration on the drawing. Lenght is 110mm.

Thanks for all ;-)
Laurent