Different Regulator Designs.....

[garywong007]

Lately I have been reading a book called Scuba Regulator Savvy by Pete Wolfinger. It is a great book (I would say the best I have read so far regarding diving regulators). It explained in great details the physics of regulators as well as how each different designs of regulators work. Yet, there are still some questions I couldn't find answer in there and I hope someone can help on this:

1. Mr. Wolfinger gave a 180-degree (i.e. referring to the angle of the direction of the air coming from the cylinder and the direction of the opening of the valve), flow-by piston-type 1st-stage as an example and illustration of an unbalanced 1st-stage and my question is : Is a 180-degree, piston 1st-stage ALWAYS unbalanced? What if the piston is a flow-through design? Would that make it a balanced 1st-stage even it is still at 180-degree? If the answer to this question is "Yes", has any brand/manufacturer even produce such a 1st-stage?

2. Is there such a thing as a 180-degree diaphragm-type 1st-stage?

3. Is a diaphragm-type 1st-stage ALWAYS a balanced 1st-stage?

Thank you.

 

[axxel57]

Lately I have been reading a book called Scuba Regulator Savvy by Pete Wolfinger. It is a great book (I would say the best I have read so far regarding diving regulators). It explained in great details the physics of regulators as well as how each different designs of regulators work. Yet, there are still some questions I couldn't find answer in there and I hope someone can help on this:

1. Mr. Wolfinger gave a 180-degree (i.e. referring to the angle of the direction of the air coming from the cylinder and the direction of the opening of the valve), flow-by piston-type 1st-stage as an example and illustration of an unbalanced 1st-stage and my question is : Is a 180-degree, piston 1st-stage ALWAYS unbalanced? What if the piston is a flow-through design? Would that make it a balanced 1st-stage even it is still at 180-degree? If the answer to this question is "Yes", has any brand/manufacturer even produce such a 1st-stage?

2. Is there such a thing as a 180-degree diaphragm-type 1st-stage?

3. Is a diaphragm-type 1st-stage ALWAYS a balanced 1st-stage?

Thank you.

No, inline 1sts ( which you call 180 degree 1sts) are not all unbalanced piston 1sts.

There are different inline 1sts designs, which are flow through piston 1sts, so they are balanced (for example TUSA TR-350s and others).

Inline 1sts piston designs can be also balanced without being flow through designs, but flow by designs (some Sherwood 1sts from the 90ties).

Sure there are also diaphragm inline 1sts, the probably most known is the Mares MR12.

No, diaphragm 1sts, also inline 1sts are not always balanced, see Cyklon 1sts from Poseidon.

 

[Nemrod]

And with the advent of balanced second stages the need for a tight control over IP has been significantly diminished and unbalanced piston first stages like the Mark 2 Evo can supply all the gas volume any two divers would need at 100 feet (or more) (CE 250A certification minimum) and all the gas volume any diver would need at recreational sport diving practical depths. And do so with minimal moving parts count and O-rings and other consumables with extreme reliability. The book mentioned does not really address reliability or parts count or performance potential, just function and theory. Excellent read though.

The USD/AL Conshelf/Titan/Titan LX and others are inline diaphragm and known for reliability and tight balancing variance despite a fairly low flow performance compared to piston regs and even the unbalanced piston type Mark 2 Evo.

 

[lowwall]

And with the advent of balanced second stages the need for a tight control over IP has been significantly diminished and unbalanced piston first stages like the Mark 2 Evo can supply all the gas volume any two divers would need at 100 feet (or more) (CE 250A certification minimum) and all the gas volume any diver would need at recreational sport diving practical depths. And do so with minimal moving parts count and O-rings and other consumables with extreme reliability.

Another way to look at it is the tight control over IP by good balanced diaphragm first stages allows the use of unbalanced second stages like the Mares Abyss or Conshelf XIV with minimal moving parts count and extreme reliability.

 

[Nemrod]

Another way to look at it is the tight control over IP by good balanced diaphragm first stages allows the use of unbalanced second stages like the Mares Abyss or Conshelf XIV with minimal moving parts count and extreme reliability.

Well, yes, that is why I specifically said balanced second stages. I agree .

 

[garywong007]

Thank you guys for your information and insights - it really helps.

 

[BoundForElsewhere]

Thank you guys for your information and insights - it really helps.

you're lucky. usually we just confuse things.