8" PVC Ball Valve - Drainage Line

Try the results from a previous post:

http://cr4.globalspec.com/thread/7496/8-Dia-PVC-Flanged-Ball-Valves

If you have a lot of money try the below:

http://www.ballvalvesolutions.com/

If these are not right for you, please supply further detail on the application:

Is it off flow from a land fill, so you expect mostly water or a slurry mix?

Why ball valve over a gate for this size and application?

What head pressure are you expecting against a closed valve?

Why PVC do you expect extremely corrosive materials?

Which you should be aware of since you posted the referenced thread as a Guest.

There is a possibility that some fine grained material could enter the line and prevent another type of valve from closing tightly,which is a requirement in this application.

Thanks for your response

Bob

I use gate valves up to 6" on forced sewer mains and because of the low pressure do not have a problem with passing around the rubber wedge, I have also tied into lines upto 14" that have had cast iron gate valves with the rubber wedge, to isolate them without any problems. But will often experience problems with passing with these valves on large water mains. As an alternative you could install a two gate valves in series for added assurance, It will also give you the option closing the first valve and then having a small pressuried line with BFP connected in to the second one to flush any material out that could prevent it from sealing before closing it (Maybe a little too complicated). I take it a butterfly valve is too likely to clog when open or will restrict flow?