Coupling a DN400/PN10 flange to a a B16.5/150 Butterfly valve

[Zachary Gagnon]

Hi all,

We are installing a new asset in our plant and are looking to do the proper coupling between the asset's integrated DN400/PN10 exit flange and the already-purchased B16.5/150 butterfly valve. Since dimensions differ slightly between the two flanges, we are considering getting a coupling part machined. I was wondering if you had any idea of an off-the-shelf solution to this issue?

Thanks,

 

[LittleInch]

Two flanges welded back to back?
Buy a DN 400 PN 10 valve?

What is a Coupling part machined?

got some drawings or dimensions?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Heaviside1925]

OP,
The only "off the shelf" solution I see, is contacting the butterfly valve supplier and see if they have a DN400/PN10 butterfly valve "on their shelf" that they would swap you out for or charge you a minimal restocking fee. I am assuming to install the butterfly valve, you are having to install new piping or cut into existing piping, if so, what is you pipe spec? and why not make the transition in the piping? unless there is a need for the valve to be close coupled to the equipment or it's prohibited by your specification. I guess my final question is, who screwed up? the asset vendor or the person who bought the valve? because then the responsibility would fall back on them. The only other situation I could think of, is your boss gave you this valve and told you to make it work.

 

[Zachary Gagnon]

LittleInch,

Two flanges welded back to back? Not welded, but bolted together yes.

Buy a DN 400 PN 10 valve? We have already purchased a B16.5 Valve and I've been tasked to see if I can make it work without buying another valve.

What is a Coupling part machined? A Part that we would design to fit our needs and subcontract to get machined

 

[Zachary Gagnon]

Heaviside1925,

Thanks for the tips, I'll look in both those directions and see if I can make it work in our case. Were the ones who messed up when ordering the valve, so I'm trying to make it work!

 

[Heaviside1925]

OP,
To LittleInche's point of just buying the right valve. Yes, you could have a custom fitting fabricated but once you add up the engineering cost, fabrication cost, project delay due to lead time and the final installation costs, I would wager a new valve being the more cost-effective option.
Additionally, you make the statement of "our plant", so I would assume you have QA, mechanical integrity, PSM programs along with corporate and/or plant specific piping specifications, all of which you would be required to adhere to. Have you done the due diligence to see if a custom fabricated coupling would even be allowed in this service by the aforementioned stakeholders?
Lastly, I would assume in this service your custom fabricated coupling would be pressure containing. Have you considered what codes and standards you would use to design this? Would this be considered a pressure vessel since it certainly is not piping?

 

[Heaviside1925]

OP,
One more comment and one more cautionary note.

Your idea may very well be the best solution, just making sure you are looking at the big picture.

Be damned sure this valve you purchased by mistake is acceptable and appropriate for this service, not just "it looks close". Do your reviews, do you calcs, do your due diligence. It is much less of an embarrassment to admit your mistake at this point than 5 years from now if you have a catastrophic failure.

 

[LittleInch]

Weld a WN PN10 flange to a class 150 WN flange....

Bolt the PN 10 to the PN 10 flange and the class 150 to the 150 flange. Job done.

That's what everyone does when you have two different flange types.

Or buy a new valve. I mean really how much is a butterfly valve? We've all made the same mistake from time to time, Just swallow a bit of pride and do the right thing.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.