NEWBIE WATER BALLAST PUMP QUESTIONS

[subdog]

Needs some help. I am trying to ascertain what I need to make a sub dive and ascend for the static dive set up below:

I want to use a water ballast pump to pump water from outside the hull into a sealed container I will use as a water ballast tank. I want the same pump to be able to pump the water out also from that ballast tank.

a. Do I need a in/out valve for this or is there a pump that will accomplish this without a valve? It seems it would be easier to simply run one hose from the pump to the water ballast tank and the other to the water.
b. Do I need a reserve switch attached to the pump to accomplish this?
c. Where can I buy both pump and switch?

Thanks beforehand..

[silent runner]

try looking here: http://www.mikessubworks.com/page1.html

Mike should

try looking here: http://www.mikessubworks.com/page1.html

Mike should be able to fix you up with what you need.

[subdog]

Thanks for the reply....I saw

Thanks for the reply....I saw that pump and valve system but understood that one requires somewhat of a snorkel to replinish the air that is discharged. Correct me please if I am wrong on that....

I think....What I want to do, is to find a pump that will pump the water into a sealed ballast tank, compress the air, then be able to pump the water out. Do you think that pump and reverse switch would do that?
Thanks again.

[Guest]

Many people use the system

Many people use the system you describe here in the UK.

They tend to use windscreen washer pumps.

You can purchase these new at a motor factors, or you can spend an afternoon in a car breakers fishing them out of scrap vehicles.

These pumps tend to be of the centrifugal impeller type, ans as such are not air tight, so you need to install a check valve.

This can be as simple as a servo pinching up a piece of flexible tube feeding the pump. The same servo can be used to actuate a microswitch to start the pump.

Microswitches are available from ebay or electronic retailers i.e. Digikey, Mouser etc.

Get a model rated for at least 5 amps.

Andy

[subdog]

Thank you..that helps a great

Thank you..that helps a great deal.

[subdog]

Any thoughts or familiarity with

Any thoughts or familiarity with these pumps located at

http://www.ripmax.com/item.asp?itemid=L ... tegory=010

I assume they need some type of valve to prevent water from coming in when they are not in operation.

I am also wondering if the pumps will pump water BOTH in and out?

Many people use the system you describe here in the UK.

They tend to use windscreen washer pumps.

You can purchase these new at a motor factors, or you can spend an afternoon in a car breakers fishing them out of scrap vehicles.

These pumps tend to be of the centrifugal impeller type, ans as such are not air tight, so you need to install a check valve.

This can be as simple as a servo pinching up a piece of flexible tube feeding the pump. The same servo can be used to actuate a microswitch to start the pump.

Microswitches are available from ebay or electronic retailers i.e. Digikey, Mouser etc.

Get a model rated for at least 5 amps.

Andy

[Guest]

That is a 'gear' type

That is a 'gear' type pump. They work well, although can be a little slow if your tank is large.

They will pump in either direction. The centrifugal pumps I mentioned will only pump in one direction. However you can use the compressed air inside the ballast tank to blow the water out through the pump.

Other alternatives include sureflow diaphragm pumps and peristaltic pumps. Both tend to be self sealing and will work in either direction.

Peristaltic pumps tend to be a little slow, and can be bulky when compared with centrifugal or gear pumps.

Andy

[subdog]

So, if I use the

So, if I use the ripmax gear driven pump that will pump water either direction, do I need some sort of a valve to keep the water from coming back thru the pump or will the gear type pump itself keep the water out?

[Guest]

The Ripmax pump, or any

The Ripmax pump, or any other type of geared pump will not self seal, so you will need a check valve of some description, yes.

Andy

[subdog]

Whats would you recommend that

Whats would you recommend that would be a good check valve that would work with a RIPMAX gear driven pump?
Thank you.

[subshop]

SUBDOG, I was thinking about

SUBDOG, I was thinking about using a fuel transfer pump made by Slimline. they make products for r/c cars and planes. it is a peristaltic pump and works on 12v. see here http://www.slimlineproducts.com ...
neil

[anonymous]

Hi Subdog,

If you are still

Hi Subdog,

If you are still interested in using the gear type pimp (as in Andy's suggestion) search this message board or have a look at my postings. (There was a lot of recent lively discussion on the use of pressure tanks and types of check valve.)

Have fun!

Davy

[subdog]

Yes..i will. Thank you.

Yes..i will. Thank you.

[anonymous]

Sorry I did mean pump!

Sorry I did mean pump!