soft seat wafer butterfly valve

[guanghui an]

for soft seat wafer butterfly valve, can the connecting flange on piping be a slip on flange? some valve vendor suggest to use special flange for soft seat wafer butterfly valve. Can we use weldneck flange instead of special flange?

 

[mk3223]

Depending on the piping size and pressure rating, it may be acceptable for either slip-on or WN flanges.
What other kind of the special flange suggested by the vendor?

 

[LittleInch]

I suspect the issue is that a slip on flange, because it is welded at the flange face, there could be bits of weld metal sticking down into the valve if it's done really badly or if you have a thick pipe.

you need to look at the dimensions of your particular valve and see if there is or could be any interference between the disc and your pipe.

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

 

[guanghui an]

firstly thank you for mk3223 & Littleinch, the vendor suggested special flange see below, the small end connect to valve, the large end connect to pipe.

 

[mk3223]

It looks like that the "special" flange is a modified "SW" joint with a larger size. It seems that there is no interference issue of the valve disc to the pipe ID.
Instead of "special" flange, IMO, the standard WN flange per B16.5 is a correct design for this application, if the slip-on flange is not suitable for the operating condition.

 

[pennpiper]

guanghui an
What is the Line/Valve size?

Sometimes its possible to do all the right things and still get bad results

 

[guanghui an]

Hi, Pennpiper, the valve size is DN500.

 

[guanghui an]

thank you Mk3223