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Homemade pressure regulator

Posted: Sun Nov 18, 2007 2:50 pm
by Gunner
I would like to have some comments, I just invent it from my head.
I going to test it someday :D .

Posted: Sun Nov 18, 2007 5:56 pm
by jrrdw
Any details? I can take a guess on how you intend it to work, but.....

Posted: Sun Nov 18, 2007 6:12 pm
by frankrede
Why not just use a regular air regulator?

Posted: Sun Nov 18, 2007 6:17 pm
by ShowNoMercy
Thats already invented though.... steam plants used to use something like that. Old ones still do.

Posted: Mon Nov 19, 2007 10:45 am
by psycix
I always wondered how regulators worked... :D
Good thinking and good luck testing. I would like to hear the results.

Posted: Mon Nov 19, 2007 10:49 am
by Fnord
Am I the only one that doesn't have a clue how that diagram is supposed to work?
Anyone care to explain it to someone who just got up?

Posted: Mon Nov 19, 2007 12:01 pm
by Gunner
I would like to explain that to you Fnord but because I am from Finland,I cant explain that you will understand how does this regulator works :wink:

Posted: Mon Nov 19, 2007 12:58 pm
by Brian the brain
If the pressure in the system overcomes the power of the spring ( on top of the piston) the ballvalve is closed.
The power of the spring determines at what pressure the inlet is closed, So yes..in theory this works

Posted: Mon Nov 19, 2007 12:59 pm
by psycix
_Fnord wrote:Am I the only one that doesn't have a clue how that diagram is supposed to work?
Anyone care to explain it to someone who just got up?
When the pressure increases, the piston is pushed back wich closes the valve more and more.
The valve will be completely closed at a given pressure.
When the pressure drops the piston is pushed back by the spring and opens the valve again, letting air flow in, increasing the pressure.

Posted: Mon Nov 19, 2007 1:13 pm
by Fnord
Oh... I had no idea that was a ball valve. Makes sense now.

Posted: Mon Nov 19, 2007 1:48 pm
by Ragnarok
I think it's going to have difficulties with the mechanical linkage between the valve and feedback system- try this for a design, which combines both parts into one:

Image

Should be pretty self explanatory - and it's clearly missing a stop to stop the main component shooting out if the pressure falls too low, I know that - come on, I drew it up in a few minutes - but it is something I designed ages ago.

I have a better design on the same principle that would be more reliable and have better flow control, but that would take longer to draw up - still, I plan to make it soon to try and convert HEAL for faster reloading... oh crap, I didn't mean to say that yet*

I have lots of other designs for pressure driven valves, including an automatic venting and metering system for a combustion. I'm not giving away exact details, but you may be able to make a couple of mental leaps to get the basic principles.

*Yes, I am fully aware that I could have deleted it before posting, and therefore I said it completely deliberately, whoever tries to tell me that (probably JSR I would imagine).
Still, I may go even further sometime, bringing back part of my colossally old "Timberwolf" designs that still need to see the light of day and make a shell ejecting semi-auto setup as well.

Posted: Tue Nov 20, 2007 10:19 am
by Gunner
OK Ragnarok,do you have other regulator ideas?

Posted: Tue Nov 20, 2007 11:10 am
by BigGrib
So now all you have to do is add an adjustment screw at the non valve side of the spring and you have yourself a fully ajdjustable air regulator, cool beans

Posted: Tue Nov 20, 2007 5:26 pm
by Ragnarok
That idea is pretty simple, but simple usually means reliable, or at least, easier to fix.

Using some bushings and a larger tee, you can make it a bit more reliable again, and make it more precise by controlling the flow better as it approaches the set operating pressure. I'll scrawl a copy up later.

Posted: Tue Nov 20, 2007 5:34 pm
by dongfang
Hi,

Try to look at a diving regulator:

http://en.wikipedia.org/wiki/Diving_regulator

(the drawing with the caption: Diagram of the internal components of a piston-type first stage)

This can be simplified somewhat, to avoid having to seal the outside of the moving stem pipe... see my drawing.

When the intermediate pressure is too low, it can´t prevent the spring from pushing the valve open --> intermediate pressure rises.

When the intermediate pressure is too high, it will push down harder on the piston, overcoming the force of the spring and closing the valve.

The problem with the ball valve set-up is that it requires a lot of movement to control the ball valve. It will need a very long and very stiff spring. On the other hand, "my" design also is influenced a little by the force of the high pressure on the valve - a ball valve is not. If the piston in my drawing is large enough compared to the valve seat diameter, it won´t really matter though.

Regards
Soren

Regards
Soren