Swing check valves

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water gun God
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Swing check valves

Post by water gun God » Fri Jul 18, 2008 7:37 pm

Hello again,

Does anyone in the U.K. (or anywhere else) know where I can find some 15mm swing check valves that can either be shipped to the U.K. or can be found in the U.K, as the ones I am using at the moment are to strong and are not letting any water into the pump.

Thank you

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Silence
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Re: Swing check valves

Post by Silence » Fri Jul 18, 2008 7:43 pm

Too strong? That's very strange...it shouldn't take more than a couple PSI to open the valve. Are you sure the valve is pointed in the right direction?

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cantab
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Re: Swing check valves

Post by cantab » Fri Jul 18, 2008 7:53 pm

Well, the intake stroke is suction, which is limited to atmospheric pressure. Still, that's about 14.5 psi
Obviously check it's the right way. Also check it's not simply a dud.
If your reservoir is sealed, that will cause issues. You need to make sure there is an air inlet to it.
Finally, if the pump is not properly sealed, then it won't work.

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Silence
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Re: Swing check valves

Post by Silence » Fri Jul 18, 2008 8:08 pm

I don't think pressure difference is 1 atmosphere in this case. The only force holding the plunger closed comes from the spring, and it probably isn't even half a pound. If you have a check valve lying around, press in the plunger to see how easy it is. These are designed to resist flow (in the correct direction) as little as possible.

Then again, maybe I misinterpreted that...

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Drenchenator
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Re: Swing check valves

Post by Drenchenator » Fri Jul 18, 2008 8:17 pm

SilentGuy, I believe he is talking about swing check valves, not spring check valves. Swing check valves use gravity; spring check valves use springs. Gravity as power is very limiting: a swing check valve must be positioned correctly to work. If the valve is upside down, flow could go in any direction. How is the valve situated currently?

Regardless of the type of check valve used, the input should be where water entered the valve and the output where it leaves. If this is wrong, no water will ever be sucked through the valve.

It also could be that the pump seal needs lubrication, which could make the pump impossible to move well.
The Drenchenator, also known as Lt. Col. Drench.

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Silence
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Re: Swing check valves

Post by Silence » Fri Jul 18, 2008 8:36 pm

I thought Water Gun God had tried spring valves but found them to restrict flow partially or completely. I may be wrong.

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cantab
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Re: Swing check valves

Post by cantab » Fri Jul 18, 2008 9:36 pm

It shouldn't matter, since normally the check valves aren't in the PC to nozzle pathway, which is the only one where flow really matters.

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water gun God
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Re: Swing check valves

Post by water gun God » Sun Jul 20, 2008 11:35 am

At the moment I am trying to use spring valves (as they are the only ones I can find).

I'll try doing the things you said and I'll get back to you

Thanks

P.S Iknow this is going to sound really stupid but the arrow on the valve does indicate the direction of flow, doesn't it?

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SSCBen
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Re: Swing check valves

Post by SSCBen » Sun Jul 20, 2008 12:11 pm

Yes, the arrow is the direction of flow. You usually can blow into the valve to determine the direction too.

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water gun God
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Re: Swing check valves

Post by water gun God » Sun Jul 20, 2008 6:25 pm

Thanks everyone for your comments, it was just that the first valve in the pump was sticking it now works fine. What would you say is the best sized nozzle?

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cantab
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Re: Swing check valves

Post by cantab » Sun Jul 20, 2008 8:35 pm

Experiment and see!

Also, 'best sized' depends on what you want to do, hence why many stock guns have selectors. There will in theory be a size that gives optimum range, However, you'll probably find a spread of sizes where the range changes little if at all. Still, too small or too large and range will drop. A smaller nozzle will give a longer shot time but has lower output. A larger nozzle may be less affected by wind and obviously has more output. It's up to you whether you think it's worth sacrificing range for other advantages. Gamewise, if you play OHK, then have the smallest optimum-range nozzle. If you play soakfest, consider larger. With PVC, interchangeable threaded nozzles are common. If, however, you're using copper, that may be more difficult.

Also, if your gun is capable of high flow, check out the laminator nozzle.

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water gun God
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Re: Swing check valves

Post by water gun God » Mon Jul 21, 2008 6:43 pm

Ok thanks.

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SSCBen
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Re: Swing check valves

Post by SSCBen » Mon Jul 21, 2008 7:36 pm

To expand on what cantab said, it's best to have a variety of nozzles to use what's best for the moment. There's different game types, different styles, different situations, etc. Generally I find it helpful to have small, medium, large, and riot blast nozzles. One nozzle should be optimized for range. The small nozzle is useful when you don't want to waste water. The medium nozzle would probably be good for most situations when you don't need higher firepower but need higher range. The large nozzle helps when you need more firepower. And when you want to take out a group or just soak someone to the bone, the riot blast is good.

devvo
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Re: Swing check valves

Post by devvo » Mon Jul 21, 2008 8:04 pm

screwfix.com do check valves, also berrys, plumb center, BSS, they all have pickup desks in every city. you could try switching to a different spring if you have one handy (some check valves unscrew) or it could be that the check valve sticks (happens a lot if its a used valve)

and they dont usualy do swing check valves in the uk under 32mm, there simply not practical in domestic situations

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water gun God
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Re: Swing check valves

Post by water gun God » Wed Jul 23, 2008 6:30 am

Thanks again

Screfix was where I got the valves from

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