Gate valves for general isolation use

[alexp78]

Can gate valves be used as isolation valves in general, e.g. basins, baths. The bigger bore may give a better flow. Or is there a problem with furring up?

 

[Plouasne]

What's wrong with a compromise, use full bore quarter turn ball valves, gate valves over time tend to stick, that's why they should be open full bore and then backed off a turn and a half, so that they could be opened slightly, to try and break the crud that's stopping a person from closing the valve

 

[MarkB]

As Plousane suggests, I would always use a full bore 1/4 turn valve in preference to a gate valve. You should only use gate valves on low pressure systems ie cistern fed.

So many gate valves eventually seize or will just not shut off properly. If I ever have to remove a gate valve (unless it's used for balancing) I replace it with a 1/4 turn.

 

[Bob Croft]

I am with Plouasne and Mark B. I like 1/4 turn lever valves for the reasons alreeady given and because they are easier to use and more reliabe.

 

[Winston]

I hate gate valves they are useless I dont fit them if I can aviod it, try full bore 1/4 turn iso valves.

 

[Bernie2]

Got to admit, like it or not there are probably thousands and thousands of gate valves fitted. But the common household ones are full bore for low pressure systems usually with a simple gate. The idea of them being full bore is to cut down on pipe flow restriction of course. A 1/4 turn valve is a bit like an old fashioned plug cock idea but up dated. They are probably great for domestic and some commercial but the problem on commercial and industrial is that you might turn fast moving water off too fast and cause water hammer.

Stop valves are an interesting read if you can find any info its not as straight forward as it looks and there are all kinds of gate valves and suggested positions to site them. Some people suggest installing them upside down, so that if the gate does fall off it falls back into the headworks not the seat and so doesn't stop the flow.

 

[HTB]

Gate (Fullway) valves cannot be used on mains pressure.