Using surface air to blow the ballast tank

[Guest]

"closed pumps" do not allow

[quote]"closed pumps" do not allow water to flow through them when they are not running. This includes]
Positive displacement type would be the correct terminology. That is for a given revolution (no matter what the speed) they will move a fixed volume of fluid. The efficiency of the pump is deifned in part by the loss or slippage, ie it should move 1cc per rev but only displaces .9cc, as some liquid will squeeze past the gaps. A high viscoity liquid will have less slippage and something like gasoline will be a nightmare. As Andy states gear pumps do have some slippage and thus will leak slightly, peristaltic should not, or at least at this size not noticeably

[kazzer]

Here is a PDF file

Here is a PDF file on the D&E Snort system.

http://www.moonrakers.com/submarines/Snort.pdf

Posted over on Subpirates where several people have done trials ------

So, here is the deal. I ran at the lake today for 3 hours straight. I went out with a full tank of gas and I came back into port with a full tank of gas. Actually I was almost angry because when I pulled in I had to waste all the gas before sticking it in the car. What a shame. Not! Also after opening the sub up it was dry as a whistle.

If you have any questions go ahead and ask. It is operational and reliable.

See the thread at

http://subpirates.com/viewtopic.php?f=41&t=3552

[kazzer]

http://www.moonrakers.com/submarines/snort.jpg

http://www.moonrakers.com/submarines/snort.jpg for a larger pic

I



http://www.moonrakers.com/submarines/snort.jpg for a larger pic

I did a quick sketch of the D&E Snort system to better demonstrate it.

The LPB (Low Pressure Blower) is housed in the dry engine room of the Sub-driver. Both inlet and outlet tubes are run through the aft endcap.
Simply drill a small hole, insert some brass tube so 1/2" is sticking out on both sides of the endcap, then attach your tubing to that.

The exhaust tube is run into the ballast tank through the lower open blow holes. The inlet tube runs to the Snort tube in the sail. This can be made of more brass tube.

The LPB is operated by the SubES1 switch, which runs off a dedicated channel with an on/off switch. (I think mine is #5)

The normal vent and blow operation is carried out by a servo housed in the engine room, which operates a lever.
When the stick is pushed left, the servo pushes, opening the vent valve on top of the cylinder.
When the stick is pushed right, the servo pulls, opening the blow valve which is connected to the Propellant tank.

Normal running is therefore controlled by a left stick movement to open the vent valve, and a flick of #5 switch to start the LPB.

If surfacing from a deeper dive, then you simply push the stick to the right, and this blows propellant into the tank.

If you inadvertently leave your blower switch on and dive below periscope depth, the LPB will pump water into the ballast tank, but this will leave the tank through the lower blow holes, because the upper part of the tank has not been vented, and still has some trapped air. Pumping water into the ballast tank will not effect the trim.

To summarise, all you need is the SUBES1 switch to operate the LPB, and the LBP, 2-3 feet of plastic tube and 2" of brass or stainless tube.

Simply install the LPB in the dry engine room.
Install the SUBES1 switch, plu in to ch 5, and connect the LPB to it.
Drill 2 holes in the aft end-cap and insert the brass tube (silicone)
Run the inlet and exhaust pipes to snort and ballast tank. I have fixed my pipe to the ballast tank using zip-ties.

Don't forget to switch off the LPB when you have surfaced!

If you want to disable the Snort system for any reason, simply connect a piece of plastic tube to the brass tubes exiting the aft end cap.


I think I explained that properly.

[cstranc]

Thanks for the info. That

Thanks for the info. That sounds like a great setup.

[chuck chesney]

This is a question addressed

This is a question addressed mostly to Kazzer, but others may want to chime in as well. I am going to try the SNORT system in a Revell Gato, and have a couple of questions about the ballast tank vent valve. What kind is it, who makes it, and where can I get one?
Thanks in advance.

[kazzer]

The vent valve is already

The vent valve is already incorporated into the gas operated Sub-driver, so you don't need to bother about one.

[redboat219]

Here is a PDF file

Here is a PDF file on the D&E Snort system.

http://www.moonrakers.com/submarines/Snort.pdf

Posted over on Subpirates where several people have done trials ------

So, here is the deal. I ran at the lake today for 3 hours straight. I went out with a full tank of gas and I came back into port with a full tank of gas. Actually I was almost angry because when I pulled in I had to waste all the gas before sticking it in the car. What a shame. Not! Also after opening the sub up it was dry as a whistle.

If you have any questions go ahead and ask. It is operational and reliable.

See the thread at
http://subpirates.com/viewtopic.php?f=41&t=3552

So, does that mean we can lose the propel altogether.

[kazzer]

It means that you may

It means that you may probably never actually USE the Propel. We are having reports that 3 hour pond runs have consumed no gas.
However, you will now need a shot of gas for only emergency use- as the failsafe 'blow' cycle, or unless you do a really deep dive.

[cstranc]

Is this the Tee valve

Is this the Tee valve that needs to be used?

http://www.mikessubworks.com/pumps.html

I wonder what it looks like when you cut it open. The description says "two one way valves"...

[skip asay]

The “TEE” valve is basically

The “TEE” valve is basically the heart of what I’ve called the “Hybrid” system for over 10 years. Consisting of two one way valves it works like this: When the pump is pumping water in to the ballast tank, a slight overpressure is created which causes one of the balls to lift off its seat thereby allowing the air to vent from the tank. Running the pump after the air is out only results in water being moved through the valve with no ill effects (overpressure, etc.). When the pump is reversed to pump water out of the tank, a slight negative pressure is created which causes the other ball to lift off its seat thereby allowing air to enter the tank. At no time will both balls be lifted off their seats.
The “TEE” valve was designed to work in conjunction with the ABP pump which is a high volume, reversible pump which is always “open” when not running. This allows the water to flow through it when Propel is released in the ballast tank. The “TEE” valve prevents the air in the tank from escaping which therefore prevents water from entering when on the surface.

Skip Asay

[cstranc]

Many thanks for the explanation.

Chris

Many thanks for the explanation.

Chris

[scott t]

Since using a pump cuts

Since using a pump cuts down on the propel required to blow ballast,
could you pressurize your propel tank with enough air for an
emergency blow? Doing away with having to purchase propel
would make that ballast system more attractive.

-Scott

[skip asay]

"could you pressurize your propel

"could you pressurize your propel tank with enough air for an emergency blow?"

Sure. I don't see why not.

The pluses:
A) You won't have to spend the big bucks for Propel.
B) Your boat's weight won't change.

The minuses:
A) Depending on the size of your ballast tank and air tank, you might only get 1 or 2 blows or.....not. But, if you're boat is trimmed to be as close as possible to neutral buoyancy when submerged even if you only blow out 1/2 of the water, you'll still have plenty of buoyancy.
B) You'll have to be more careful with the tank construction since it would be possible to over pressurize with catastrophic consequences.

Skip Asay

[kazzer]

As the nominal pressure of

As the nominal pressure of the gas propellant is 70 psi, would not recommend charging the on-board bottle with an air charge of over 100 psi -- that would empty the tank about half way ... once!

As for the cost of gas, phew! Can't afford a buck a shot/charge?

Do not spend time at the pond, write job resume and get new job!

[scott t]

Thank you Mr. Skip Asay

Thank you Mr. Skip Asay for the information.

Mr. Kazzar since I don't have a WTC why don't you investigate
the use of air in one for me, then you might sell me one in
the future. You could sell it as green product since it dosen't
pass gas.

Warning about gas pressure taken well.

-Scott