"Large" Full-Bore Trunnion Ball Valves - PVC 2

[JavaMoose]

Hello all,
I'm having some problems finding full-bore trunnion ball valves in PVC. I am in need of 8in and 10in valves with 150# flanged connections. The system requires the use of thermoplastic valves, PVC would be ideal.
TVI has strong union valves, but only up to 6in, which appears to be the same with a lot of other vendors. Plenty of butterfly valves that would work, expect for the fact that the system will be pigged regularly. Anyone know of any vendors short of us having to get them custom made?
Thanks!

 

[zdas04]

I thought you might be out of luck. I've never heard of a plastic flanged valve, but there are a lot of things I've never heard of so I thought it might be interesting to look. I found a polypropylene ANSI 150 flanged valve in 8-inch at

http://www.indiamart.com/nbengineers/pp-valve-flange-ends.html

Then I found a 10-inch PVC (and a 12 and a 14 and an 8) at

http://www.pepplastic.com/index.php?main_page=index&cPath=3_169_425_2796

It took nearly 5 minutes.

David

 

[zdas04]

Of course, the last link is to Gate Valves instead of Trunion Ball Valves. My 5 minutes was up.

David

 

[JavaMoose]

David,
In my searching I did not find the valves from NBEngineers, that will be a worthwhile one for me to follow up (although, PP is going to be seriously expensive). Thanks!
On the gate valves, I was trying to stay away from those if possible, but they seem to be more readily available (I had come up with lots of manufacturers that meet my needs in gate type) and reasonable cost for their size.

 

[JavaMoose]

I should say, I think I might have to relax on the trunnion spec. Given how low-pressure my application is and that it is sea-water being pumped, a floating ball might be fine.

 

[jdarco]

I don't think you will find a full port plastic ball valve in that size. As ZDAS found, best bet for that size will be gate valves. There are also diaphragm valves available, but will be a weir style. Check out

http://www.asahiamerica.com

 

[stanier]

You could also consider a pinch valve such as by RED Valves. This gives you the full bore that is piggable. If this isnt an issue why not a butterfly valve?

"Sharing knowledge is the way to immortality"
His Holiness the Dalai Lama.

http://waterhammer.hopout.com.au/

 

[JavaMoose]

Stanier,
That's a winner! Looks perfect for our application, I've seen smaller versions of those (air operated) - didn't realize they made big-boy versions. Thanks!

 

[breaker34]

Java,
what is the reason for the need of the valve to be plastic?

 

[JavaMoose]

Breaker,
The system is a continuous service 30K liter sea-water/brine-water system, on a tight budget. Lined valves tend to be really expensive, same with exotic metals, non-metal seemed to make the msot sense.

 

[breaker34]

Java,
Ok, I understand. Thanks for the information. Good Luck.