Air Supply

How about turning the pipe upward and putting a return bend or rain hat on top?

Sounds Ok But As I Have Said Before Sometimes It WIll Be Completely Submerged And The Rest Of The Pipe Or Where It Leads To (The Other End) Is Lower Than The Opening?

Look inside a wet/dry vacuum. The answer will be obvious.

Yes But My Health Won't Help Me Solve The Problem. Thanks For The Uplifting Words Of Wit Though? Also There Is Someone On This Site Trying To Promote Their Business. Is This Allowed As I Thought It Wasn't?

It may not hurt if you check OSHA as well as archives of these forums etc. for many discussions related to safety BEFORE you employ any pvc material for "air piping".

Air/Water Separator? Have you looked at one?

I hope this "PVC air pipe" is not a compressed air pipe and just an atmospheric air pipe such as a vent. The use of pvc for compressed air is extremely dangerous and illegal according to OSHA in the USA.

If it is for compressed air you should look up previous postings to see the dangers involved and also OSHA standards via the internet (www.osha.gov). There have been quite extensive discussions about that type of use. When it breaks under pressure it forms shrapnel type shards which can injure and kill.

I once worked at a cheapskate outfit where they insisted on using it for this use and every several months a section of piping or fittings would blow and send sharp pieces flying. On one instance a coworker got a piece in his upper arm down to the bone. He got a free ambulance ride and an operation. I was more fortunate I only got a piece that required stiches.

Please, please don't take the risk. There are many people on this earth but none to spare due to stupidity.

Good Luck, Old Salt

You could look at the possibility of using a steam condensate trap to dump as much water as possible, but it may not be the only solution.

How about just adding a length of 4" pipe that would be above the highest water level. If rain water is an issue, add 2 90o elbows to the top. Dont forget to add a piece of window screen over the opening (secure it with a zip tie) to keep out the bugs and other things.

This one is way easy. Don't use PVC for compressed air (if you are), as this is extremely dangerous.

If this is some sort of air intake line under normal atmosphere, (1) never allow the opening to be below water line, and (2) install the opening with an inverted U to prevent precipitation from entering. If the line is under a slight vacuum, there may be condensation depending on ambient humidity, etc. (3) In such a case, you have to choice but to dry the inlet air with a drying agent (adsorbant beads that are re-cycled by heating).

Hi Prophet

Guessing 90% chance that the water vapor in the compressed air condenses in the pipe as the air cools. Water typically does not enter a pressurized pipe unless submerged in water that is at higher pressure than the compressed air.

To deal with water vapor you might dry the air before it enters. Talk to a compressor dealer.

To deal with condensate inside the pipe use a float operated or timed drain. A 1" in 10" slope or more toward the drain helps.

Condensate may also be removed as the air exits the pipe, about 99% with a quality filter seperator.

A Filter and dryer after the pipe will remove condensate and additional vapor and reduce the dew point (Make it dryer).

Can't valve it out. It's something in the air. Tom

Ok, First I Would Like To Say Thank You All For All Your Responses As I Know You Didn't Have To Answer And Some Of Your Suggestions Are Very Good, But I Need To Explain A Little Further That We All May Be On The Same Page So To Speak. First It Is Not A Compressed Air Site. It"s Just An Ordinary 4" Air Supply Pipe. Second It May Become Submerged Totally In Water Once In A While For Certain Undetermined Periods Of Time So Any Fix Would Have To Be Completely Air Tight. And Thirdly, While I Know One Of The Suggestions In Here Has been, I Would Say, Pretty Much Right On The Mark But I'm Not Sure I Could Build One Which Would Totally Secure An Air Tight Fit? How Would I Bevel The End Of A Flat Plastic Circular Disc Uniformly. This Also Brings Up The Problem Of Concise Circular Form? Well Anyway I Sure Wish I Could Build One To The Correct Specs But Lack The Necessary Tools In Availability? I Really Think Someone Should Start Producing A Cheap Product Like This. I'm Sure Upon Advertisement You Could Make Millions. I Know If I Could Build One, It Would Save Me A Lot Of Heartache In The Future And I Certainly Would Advertise It To Build A Nice Little Nest Egg. I'm Sure You Know The Expression, Build A Better Mouse Trap And The World Will Beat A Path To Your Door Especially If It's Cheap And Affordable For Someone.

OK then, how about some type of floating ball valve like skin divers use to seal out the water when they dive?

So what exactly is this thingamajig for? Is it a snorkel for a sneaky minisub packed with explosives, intending on doing harm to someone? Is it a snorkel for a jeep? You are too late to invent this, as my uncle came up with it somewhere in France in 1945, I think in July.

I think we need a little more information here. Where is the exsiting pipe, ? on the ground,? on a building with a flat roof,? ..is it now Hor. ? Vert.? on an angle. What are (if any) the limitations. Drawings would be a great asset to everyone. (Were only Guessing Here).

And people read the OP properly....Stop Water But CONTINUE To Supply Air,..

What are you trying to do? Maybe a Snorkel.

OK not compressed. You can forget everything after good morning.

Using ABS cement and adapters you can make just about anything that you wish your pipe to be. Gore Tex or the equivalent blocks water but lets air and vapor pass.

As you are trapping better mice you limit the explict information to give good answers.

I got caught assuming once. Good luck anyway. Better mice need trapping also. Tom

I'm Not Sure What You Mean About Gor-Tex But It Sounds Interesting. Give Me Some Ideas Please? Tell Me Exactly How You Would Build One And I Just Might Try It Out?

Thanks.

Well if that's all this is about

http://www.google.com.au/search?q=disguised%20towers

Wiith this system the more explicit and descriptive the question is the better the answers usually are! You can hardy blame the responders for not posting answers that clearly solve your problem or becoming frustrated because they can't seem to get it right. Sort of like shooting a target with fuzzy glasses that you have supplied the shooter, the clearer the classes the more accurate the shot!

I for one posted a answer about the perils of using pvc for compressed air. If I had known that it wasn't for use for compressed air maybe I could have come up with a perfect answer for your problem. Now that I know more about your problem I would suggest you use a flapper hinged on top of the pipe with a float on the other side of the fulcrum. As the water level increases the float rises and forces the flapper down to seal off the top of the pipe (adjust float height to provide a complete seal), as the water lowers the float drops and the flapper opens. Sort of like a a cross between toilet flush valve with a float on the other side of the fulcrum. Another illustration would be the flapper on top of a vertical diesel truck exhaust but with a float secured to a rod on the other side of the fulcrum.

Perhaps you could have had your problem solved with several excellent solutions within a day or two if more information had been suppied initially,

Good Luck, Old Salt

There is a compressed air dryer (I know yours is not compressed) that utilizes "The latest in membrane technology~~~extremely low pressure drop~~~ no power required.

It works somewhat like gore-tex the material used in bandages for burn victums later converted into rain wear by the company the trade marked Gore-Tex.

Semi permeable membrane allows dry air to pass but removes water and water vapor. Do your reaserch. This might require a pump or bellows to compensate for the pressure drop but if it was easy everyone would have a patent on it. Get back to me when you get rich. Tom