SpudFiles

Quick question, has anyone here used these valves:

I am looking for something alternative to a sprinkler valve that is electrically controlled for this project I'm working on.

It really needs to be air tight as the device will be sitting for at least an hour before it gets actuated. I find that sprinkler valves at pressures around 100 psi will leak slowly and run out of air... Sometimes they do and sometimes they dont leak, but either way i need something a little more reliable. So I figured something used for Gas would be better than something used for water..

I found these:

http://cgi.ebay.com/3-4-24V-DC-Electric ... 1602570285

http://cgi.ebay.com/12v-DC-1-Electric-S ... 4086wt_905

sorry for the large links, I could use tinyurl but then people are nervous on clicking them...


Anyway, has anyone tried these or have something else that works well in being air tight..

Most of the time the sprinkler valves leak because they get dirt in them. Properly cleaned, and in good shape, they hold a seal well.

How much flow do you need? Those valves are OK with decent size orifices. The 1 inch has a 25mm orifice which is not too bad. I do not know how fast they open, but it should be feasonable.

This valve looks similar to the ones used on a popular confetti cannon that can be filled and wait for the proper time to launch.

the problem with sprinkler valves is the fact that they are meant to hold water and not gas.. Even a properly taken care of sprinkler valve leaks very slowly..

I figured something built for gas would be much more reliable in being completely air tight. At least a lot better than something built for water..

leaking gas is a much bigger deal than leaking water


Thanks for the suggestion though, can you link to a product page?

Have you considered modding the valve? For example if you prioritize seal quality over valve performance, you could swap in a stronger spring to hold down the diaphragm. Don't know if it would work but it's a thought.

Just Google Confetti Cannon and several manufactures and models show up. Many use that style valve on an air tank.
That specific one is;
http://www.nobodybuy.com/product_desc/p ... cannon.htm

Another one is on this page using what looks to be the same valve.
http://streamersandmore.com/index.html

Is some kind of airsoft claymore in the offing

Do you want multiple shots from this? You could just buy a solenoid and use it to actuate a small ball valve, if that is not enough in terms of flow you could use the ball valve to pilot a QEV.

one shot, needs to be air tight, have decent flow and electrically actuated.

the valves you posted are pretty much just like spinkler valves. Sure you can expect higher quality but they are the same

Are you sure that sprinklers really leak that much ?

Anyway, you can always use your burst disk design

POLAND_SPUD wrote:Are you sure that sprinklers really leak that much?

My thoughts exactly, I see no reason why a clean spinkler valve in good condition shouldn't hold pressure considering it's being held closed by pressure differential.

A little plastic buffing compound on the plastic valve seat may be able to take care of any manufacturing seams that makes small leaks. I have not taken a good close look at a sprinkler valve lately to see how well the valve seat is made.

Anyway, has anyone tried these or have something else that works well in being air tight..

They look like the big brothers of the valve this guy used recently:

http://www.spudfiles.com/forums/direct- ... 21895.html

(I've not just got a photographic memory I was eying these up myself the other day, they seem to be about the cheapest solenoid valves around)
For my part I've no experience with sprinkler valves but I've found check valves designed for operation with liquid don't work well with gases.

OK, I think I can give some information on this.

First off, the valves you linked to are direct acting valves, they are not just like sprinkler valves. You can tell by the location of the solenoid. When the solenoid is directly over the center of the diaphram, they are direct acting valves. When the solenoid is forward of the diaphram, they are fast acting, pressure differential valves. You want the fast acting type. The flow rate of direct acting valves is lower than fast acting valves. The confetti cannon shown looks to use a fast acting Granzow valve (it looks like a 1 inch pipe thread valve). I use them on my cannons. They are expensive, but they do hold pressure well. I tested one that held 90% of the tank pressure after 4 hours of sitting. They are available with various voltage rated coils. Even if you do not buy a Granzow valve, I would go to their web site and look at what they offer as a reference for shopping for other valves.

Lastly, if you do use a direct acting valve, go with a low voltage rated coil and over-volt it. I like using a 12 volt coil and run 24 volts to it. With a direct acting valve, you will get faster opening that way and the colenoid will not be damaged because it is only gettin very short bursts of power anyway.

I hope that helps.

Matt

not really as the ones he posted are indirect acting (piloted) while the guy bought is most likely a direct acting valve




EDIT
Lol beaten

POLAND_SPUD wrote:not really as the ones he posted are indirect acting (piloted) while the guy bought is most likely a direct acting valve




EDIT
Lol beaten

No, that is not correct. Click on the links he posted. They are direct acting, not piloted valves.

Matt

yeap, that why I posted both types