I would appreciate if someone could supply a source of large diameter gate valves (not knife gate). I only found up to 48" on the internet. I am looking for 72".
I attended a lunch seminar concerning all types of valves a month or so ago. I can't remember myself, but the guy who put on the seminar must be the guru of valves. If he can't tell you who makes one he'll tell you what the next best alternative is. Here is the contact info:
John Nangle
(630)844-4092
jnangle@henrypratt.com
He works for Henry Pratt Company
Or try their website it looks pretty impressive
Are you sure anyone even makes one? Generally, the bigger valves I've seen were butterfly valves.
The largest gate valve I've seen was 48", and those were big, heavy, expensive suckers. They were made by American, and I see on their website, they just go up to 48".
You might double check the specifications under which the valve would be produced, to see if there is a size limitation on it.
"AWWA C500-02: Metal-Seated Gate Valves for Water Supply Service
This standard covers iron-body, bronze-mounted, nonrising-stem (NRS) gate valves including tapping gate valves, 3 in. (75 mm) NPS through 48 in. (1200 mm) NPS..."
AWWA C509 just covers up through 20". I think these are the only AWWA valve standards. So while you can get larger valves, they won't be "AWWA" valves.
From a practical standpoint, this is probably the point at which you're moving from a cast-body stock item to a welded-steel custom item.
And do check the prices on other valve styles. On a 10" valve, there's not a lot of difference between a BFV and a gate valve, but the larger the valve, the more the difference. The physical size gets to be an issue as well. A 48" gate valve is about 10' high.
The service is raw sewage so something like a butterfly is out of the question. I need something with a little more beef than a knife gate. Is there a suggestion on another cheaper valve that would work? This probably is a fabricated valve but I haven't had any luck finding a fabricator that has done this before.
I'm operating at about 30 psig with a mzximum around 100 psig. This is on a pipe discharg header so the pressure will remain in the 30 to 40 psig normaly.
Parhaps a plug valve would be possible. Don't know if anyone makes such a large valve but it does have the agvantage of a fully open waterway. If the purpose is to be a shuoff valve, rather than a throttling valve, it would be normally open or completely closed.
RWF7437: I was thinking a plug would be more expensive that a gate but I will check that out.
CVG: The electical is set up for 900 hp pumps and I'm right on the edge of that. This a plant upgrade so the electrical is existing. I'm afraid any addition head on the system will push me over the line.
AWWA C515 covers larger gate valves, but I agree that the largest AWWA conforming RW GV is 48". I believe you can still get Double disc as large as 72"