Piston vs Diaphragm Regulator

[Aqua-Andy]

I read this article from an email I was sent this morning. Good info except for this part.
" Apeks diaphragm regulators are among the highest of quality. These first stages utilize a unique what they call “overbalanced” design. This means the intermediate pressure supplied to the second stage increases more than traditional balanced models as the diver descends to greater depths."

This is not unique to Apeks regs, most other environmentally sealed diaphragm regulators have this "feature". Only it is not a designed in feature it is a "design flaw" that they try to market as a feature.

 

[Captain Swoop]

Why is it a design flaw?

How does this follow from the thread title?

 

[Aqua-Andy]

Why is it a design flaw?

The "over balancing" is a result of the environmental diaphragm that is slightly larger than the main diaphragm. If you look at the design of the reg body and the way it screws together it is easier to see. Also it is not unique to Apeks.

How does this follow from the thread title?

It follows because the quote I posted came from the article. Also deceptive marketing practices are a pet peeve of mine.

 

[Captain Swoop]

Bad link, I just get 404 not found but apart from that, why do you think it's a flaw not a feature?
Apeks have been designing and manufacturing regulators for many years, they are highly regarded. I use them myself, I think they are good bits of kit, I don't see a flaw.
What’s deceptive?

 

[tbone1004]

deep diving regulators

read up. it's possible to engineer around, but they've created a bit of a marketing term around it and it really is only a design flaw with unbalanced regulators and/or extremely deep depths. At the extremely deep depths it will cause them to freeflow if you don't detune the second stages for shallow water, and with unbalanced regulators it can cause WoB issues when you do that. Not just Apeks, most if not all sealed diaphragms are prone to it. The Poseidon Jetstream/Xstream regs aren't able to work with this extreme of an IP swing since they are a semi-upstream unbalanced design, so they have engineered their first stages to not require the sealing diaphragm for cold water

 

[Aqua-Andy]

deep diving regulators

read up. it's possible to engineer around, but they've created a bit of a marketing term around it and it really is only a design flaw with unbalanced regulators and/or extremely deep depths. At the extremely deep depths it will cause them to freeflow if you don't detune the second stages for shallow water, and with unbalanced regulators it can cause WoB issues when you do that. Not just Apeks, most if not all sealed diaphragms are prone to it. The Poseidon Jetstream/Xstream regs aren't able to work with this extreme of an IP swing since they are a semi-upstream unbalanced design, so they have engineered their first stages to not require the sealing diaphragm for cold water

I have read up, this page has been around for many years. This phenomenon of IP increasing is not desirable but does not cause issues unless you are diving very deep. I guess it just bugs me when marketing departments take a known issue and promote it as a "feature". I never said It was only an issue with Apeks I said "This is not unique to Apeks regs, most other environmentally sealed diaphragm regulators have this "feature"". It is just that Apeks actually promotes it.

 

[tbone1004]

@Aqua-Andy I was more responding to @Captain Swoop with that link. I would argue though that it may be enough to help offset some WoB hits due to gas density if you are diving light in the Helium department, but if you subscribe to standard gasses where your "ideal mix" is equating to 32% at 30m/100ft, then it is unlikely to be a meaningful benefit. Deep air, sure I can believe it's advantageous, but that would require promoting deep air diving, and that would be bad...

 

[Aqua-Andy]

@Aqua-Andy I was more responding to @Captain Swoop with that link. I would argue though that it may be enough to help offset some WoB hits due to gas density if you are diving light in the Helium department, but if you subscribe to standard gasses where your "ideal mix" is equating to 32% at 30m/100ft, then it is unlikely to be a meaningful benefit. Deep air, sure I can believe it's advantageous, but that would require promoting deep air diving, and that would be bad...

Sorry, I guess I'm a little crabby today. We had a big storm come through and mess up the viz in the ocean so we scrubbed the dive for today. Earlier last week we had rain and forty something degree weather that melted a bunch of our snow. So no diving, no riding the sleds and it finally hit 16F outside. I guess I'm getting a little cabin fever.