Motorised valve to fit 90mm OD pipe

[Hooo]

Anyone know where I'd get one cheap?
It doesn't have to be great - it can leak externally and not close fully, but it needs to last a few years with no maintenance.

 

[Softus]

What are the symptoms of the plumbing or central heating problem that you want help in solving?

 

[Blasphemous]

Anyone know where I'd get one cheap?
It doesn't have to be great - it can leak externally and not close fully, but it needs to last a few years with no maintenance.

'No maintenance'..... But it can leak and you're not bothered if it closes fully.... Maintenance????? Are you bothered?

That's a great question.... what is the question by the way?

 

[Hooo]

The question is....
Does anyone know where I can get hold of a great big motorised valve? Needs to be cheap, so a secondhand one would be good. I've no idea where to look, and I was wondering if anyone here could help. I guess that's a no then.

 

[WDIK]

screwed or flanged 240v 24v 110v

 

[Softus]

What are the symptoms of the plumbing or central heating problem that you want help in solving?

 

[Hooo]

It's not going to be practical to thread the pipe on site, so I'll need a flanged valve with a flange that we can weld on. Or, I could get a threaded valve and a short length of pipe with a threaded end that we could weld onto the existing pipe.
Ideal voltage is 220V 50Hz, but I'm building the control gear so I could make it work with pretty much anything.
Working pressure is about 1 bar.
Fluid is clean water.
It's oudoors, so IP65 rating would be nice, but we can always build a box over it if that's not available.
I have manged to find some suppliers online, but they're expensive new. I was hoping there'd be a way of getting a secondhand one.

It's being installed in Africa, so there's not much in the way of skilled labour or equipment hire available, but we can get welding done.

 

[IJWS15]

Do you mean potable water and do you want it to remain potable?

 

[Softus]

Fluid is clean water.

What's the equivalent UK fluid category?

I have manged to find some suppliers online, but they're expensive new.

What do you call expensive?

I was hoping there'd be a way of getting a secondhand one.

Do you think that a secondhand one will work out cheaper in the long run?

 

[Hooo]

Do you mean potable water and do you want it to remain potable?

Good point. It's feeding a tank that is used for watering the garden, but it's fed from the pipe that fills the house water tank. So yes, it needs to remain potable. It's looking like a secondhand valve is going to be more trouble than it's worth, since I'll have to know what it's been used for.

 

[Onetap]

Anyone know where I'd get one cheap?
It doesn't have to be great - it can leak externally and not close fully, but it needs to last a few years with no maintenance.

They're not cheap.
Look at http://www.everyvalve.co.uk/
cheapest I know of, but I don't know if their stuff is any good.

I think you'd need a motorized ball or butterfly valve. A butterfly would be cheapest.

The other option, probably the cheapest, would be a diaphragm valve. The diaphragm could then be operated by a small solenoid valve, so you don't need an expensive motor. You need a strainer to protect the solenoid valve.

You could collect a bunch of small (22mm?) diaphragm valves from scrapped combi boilers, but you'd need a few to give the equivalent area of an 80mm valve.

 

[Hooo]

Everyvalve look like the sort of site I was looking for, it looks like they might have odd surplus stuff. I'll give them a call and see if they can help. Thanks for the tip.

I did think about using lots of small valves, but it seemed like a lot of work making the manifold.

 

[WDIK]

Do you mean potable water and do you want it to remain potable?

Good point. It's feeding a tank that is used for watering the garden, but it's fed from the pipe that fills the house water tank. So yes, it needs to remain potable. It's looking like a secondhand valve is going to be more trouble than it's worth, since I'll have to know what it's been used for.

it doesnt need to be potable if its feeding a downstream tank not for drinking water so long as it has a an airbreak ie a ball valve or such like situated above the tank.

you say its for some project in africa? does it realy need to be automated?

the reason I ask is frankly i would have thought there would be a surplus of labour, and buying a watch is going to be cheaper than buying a weather proof actuator, and easier to maintain.

something like this is cheap and cheerfull

or something like this is going to cost an arm and a leg

 

[Hooo]

We have a manual system in place at the moment, and it does work, but it's not exactly ideal.
It works like this. A borehole pump fills a watertower for the house, and a ground level tank for the garden. When the water stops in the house, someone goes out and finds one of the workers who wanders down and switches the pump on (about half a mile away). After a while he notices that the water tower is overflowing, so he wanders to the garden tank and opens a gate valve in a pipe Td off the main feed. Since the water tower is about 10m higher, all the water now flows into the tank. Sometime later he notices that the tank is overflowing, and he wanders down and switches the pump off.
In theory we could schedule a pump run at a regular interval and watch the tanks, but the workers really don't do schedules....
There are tenants who whinge every time the water goes off, so it would be good to get something to make it reliable, however it's not vital, so if it's going to cost a fortune it's not worth doing.
I can build all the level sensing, radio control (half mile from the tank to the pump!) and pump switching, but the valve had me stumped.
I thought about getting an actuator for the existing gate valve, but it's 10 turns to open, and I won't be able to go out there and play around, I need to build a working system and ship it. Plus it flows about 30l/min when it's closed, so it's pretty knackered.

The garden tank is open on top and the outlet is 500mm above, so no chance of back siphoning.

I've now found this, which looks like it'd do the job:
http://www.valves-online.co.uk/acatalog/copy_of_zzz.html
£230 for a 3" one, does that sound like a good deal?

 

[Onetap]

It works like this. A borehole pump fills a watertower for the house, and a ground level tank for the garden. When the water stops in the house, someone goes out and finds one of the workers who wanders down and switches the pump on (about half a mile away). After a while he notices that the water tower is overflowing, so he wanders to the garden tank and opens a gate valve in a pipe Td off the main feed. Since the water tower is about 10m higher, all the water now flows into the tank. Sometime later he notices that the tank is overflowing, and he wanders down and switches the pump off.

I've now found this, which looks like it'd do the job:
http://www.valves-online.co.uk/acatalog/copy_of_zzz.html
£230 for a 3" one, does that sound like a good deal?

Omit the valve, save £200; control it by float switches.

A low level switch in the house tank starts the pump. The tank fills above the overflow pipe, and the garden tank is filled by the overflow. A high-level switch in the garden tank stops the pump. Easy.