Miminum pressure for Orbit 1" and hydro testing?

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zerodivide
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Fri Sep 08, 2006 10:44 am

I have a 9" x 1.5" chamber with an Orbit Watermaster 1" on the end. To check for leaks I filled the chamber with faucet water. Found that plugin schrader could move and leak so I filled it with epoxy. It holds water now.

1) While doing this I noticed that the orbit would leak a small amount of water on the 'output' side. The manual says this is normal but doesn't say what pressure it should seal. What's your experience with it?

2) I tried filling the chamber with a bit of air but the psi needle only goes as low as 20 on my compressor. Is there a minimum pressure where the watermaster starts to seal?

3) For a hydrotest I assume that the right way to do it is to connect the threaded chamber to a garden hose and fill it with water.

http://www.iodbbs.com/assessories.html

If there are no leaks, how do you know when to stop? When the hose starts leaking?
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carlbelcher
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Fri Sep 08, 2006 1:24 pm

First of all what kind of compressor do you have?! 20psi is pathetic!

Second, is it modified? If it is, make sure you left the spring in when you modified it. You might also try putting some heavy grease on the diaphragm, it helps it seal.

Also if the valve is modified, and had a guide rod try reducing the equalization hole size.
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MrCrowley
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Fri Sep 08, 2006 4:16 pm

carl i think he meant the gauge only goes as low as 20psi eg the gauge has a range of 20-250psi so he cant tell if somethings 5psi.
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SpudStuff
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Fri Sep 08, 2006 5:36 pm

Ummm Grease......
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carlbelcher
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Fri Sep 08, 2006 5:40 pm

ah... you're right. Maybe I should learn to read a little better. :oops:

Anyway... The point still remains the valve should probably seal as low as 20 -30 psi but if it doesn't you can try the other things in my last post.
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frankrede
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Fri Sep 08, 2006 6:42 pm

carlbelcher wrote:First of all what kind of compressor do you have?! 20psi is pathetic!

Second, is it modified? If it is, make sure you left the spring in when you modified it. You might also try putting some heavy grease on the diaphragm, it helps it seal.

Also if the valve is modified, and had a guide rod try reducing the equalization hole size.
He means that his pressure guage doesnt go lower than 20psi, so all he knows is taht its below 20psi?
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frankrede
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Fri Sep 08, 2006 6:43 pm

Whoops i didnt read all the posts sorry
zerodivide
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Fri Sep 08, 2006 6:57 pm

Hi guys, thanks for all the replies. Here are my findings:

1) My 250psi 12V electric compressor is crappy. The meter starts at 20psi and goes to 250psi BUT the connector is so brittle it wasn't doing a good seal
with the schrader. A good connector will eat up all the thread on the schrader. No seal = no air therefore needle wouldn't move.

2) Buy a cheap hand/foot pump. My chamber is only 9" long. It took about 6 mild pushes from a $7 footpump (Ace Hardware - the 100psi Hi volume one) to bring it to 30psi. With the pump's line still connected my chamber does leak a few psi for a few minutes. At a little over 30psi the valve+epoxy+telfon on thread held the pressure for about a minute. At below that it was losing 2psi every few minutes. Since I've epoxied the schrader's rubber it's probably the bike pump or the Watermaster that was leaking below 30? I'll have to try leaving it for about half an hour next time.

Popped the manual level on the Watermaaster and I got a satisfying thump. Still need to do a hydropressure test before I go higher than 30psi (my arbitrary safe level). Went to the homedepot where I was shown brass and steel connectors that will let me go from a 1" male threaded PVC to a gardenhose connection. My intent is to fill it with water from a hose until I see a leak or the line starts to go taught. Please enlighten me if this is not the right way to do it. :)

Oh, its not modified. With my first cannon I'd like to play with it 'stock' to understand all the basics.
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zerodivide
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Sun Sep 10, 2006 6:25 am

Thanks for the link. I wish I had an integral pressure gauge in the chamber but now that link has given me the idea to get steel/brass fittings to connect an air pressure gauge without making more holes in the chamber. Noticed that PVC vs Steel, the steel seems to leak. Probably just not enough teflon. The chamber held but the cannon didn't perform to expectation overall. 60-70psi only got me 10 feet or so using the manual bleed trigger. I wonder if it will perform better with an electric trigger or if I'm losing a lot of pressure when disconnecting the pump from the schrader (loud hiss -- can't tell if it's air from the hose or from the chamber).


BTW, found an interesting question about Air pressure vs Water pressure:

http://www.onlineconversion.com/forum/f ... 997724.htm

http://www.leaktools.com/professional/i ... essure.php



One link mentioned pressure testing at 20psi for 2 minutes is sufficient to detect a pipe or fitting leak when using air or water.


Update: Looks like removing the bike pump was letting out too much air. Findings continued in another thread .... http://www.spudfiles.com/forums/viewtopic.php?t=3529&
Last edited by zerodivide on Sat Sep 16, 2006 5:33 pm, edited 1 time in total.
zerodivide
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Last edited by zerodivide on Sat Sep 16, 2006 5:33 pm, edited 1 time in total.
zerodivide
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Sat Sep 16, 2006 3:20 pm

New issue with a different valve.

Image

Gave my old valve away. Bought a new Orbit Watermaster (had to go out of state, doh!). Also tried new air fill I made up. The air fill part has a ball valve connected to a schrader to eliminate pressure loss from removing the bike pump. But the new sprinkler valve apparently won't seal.

The bleed lever is in the closed position. And the airfill is hooked up to the right part of the sprinkler. When I pump it with air it just comes out the sprinker. Tried the airfill pipes with water and it has no leaks. But when I invert the sprinkler it leaks a bit (expected). I shake it and it leaks some more. And get this, opening the ball valve to the schrader causes the sprinkler to dump its contents as if I opened the manual bleed.

So I took out the ball valve and left just the schrader. Another water test on just the pipes it seems okay. Then I close the system by attaching it to the sprinkler. Pump air into the chamber and water comes out. Broken diaphragm? Or is there something else I'm doing wrong? I'm probably going to open up the sprinkler to get a look see. But if you have any hints, I'd appreciate it.

UPDATE: Opened the top to look for "foreign objects". The only thing I found was some water. That's normal isn't it? Closed it back up but still no joy.

Image
zerodivide
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Sat Sep 16, 2006 4:03 pm

UPDATE AGAIN: Just for kicks, tried to fill one end of the sprinkler with water from the faucet. It just went straight through. Inverted it, same thing. Looks like the valve isn't working. The last watermaster I had would hardly leak water even with the bleed lever open. I guess this one is busted, unless someone knows better.
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carlbelcher
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Sat Sep 16, 2006 4:07 pm

Have you ever tried the edit button?! Four in a row I think that's a new record.
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zerodivide
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Sat Sep 16, 2006 5:38 pm

OT: Hahaha, sorry. The first two in that set were dupes from different dates though (fixed it).

Got lucky and found a Lowes that sold a Rainbird CP-100. Tried that and it had no problems holding pressure. Looks like I learnt a good way to test an inline sprinkler valve if it's bad.

- Hold it under the faucet (careful not to spill). There should be a small trickle of water on the bottom but it should stop momentarily and hold water.

If you put water in the chamber and invert it then shake, it should not leak.


UPDATE: Went out of state again and passed by the local Home Depot to pickup another 1" Watermaster. Tried my "test" on it and it leaks like the previous one. It looks like the chamber has to be really airtight for the diagphragm not to leak when inverted. How did I find that out? I took an a filled water bottle (from a used aquafina 20oz) and surrounded the lip with wet tissue paper to make a makeshift seal. With the bottle right side up I put the watermaster on top. Checking to make sure the bleed lever was 'off', proceeded to invert the watermaster + water bottle. Air bubbles in the chamber corresponded with water going out. When I had it completely inverted and the bottle settled, the bubbles in the chamber stopped and so did the leaking. Carefully dried the out port and then left it for a while to see if it would drip. No drip. Looks like the Rainbird CP100 seals easier than the Orbit 57101. Is that a good/bad thing? I don't know. It just means, if you can't fill with this watermaster then you probably have a leak in the chamber.
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