Is enviro seal really halping in some cases?

[markr]

We're talking about different things, I think, I was addressing changes in IP vs the drop from supply (potentially 3000+PSI) to IP vs IP to ambient, which would consistently be about 125-140 PSI. (IP is usually thought of in PSIG, not absolute)

You might be overlooking something with your numbers for IP change at depth; IP always depth compensates along with ambient. So at 160 ft (lets say 5 atm for simplicity) IP for a regulator set at 135 PSI would be 135 plus somewhere around 73 PSI, or around 208. That keeps it constant above ambient, otherwise it wouldn't work. "Overbalanced" regs increase the IP even more, elan's example was that he thought it might increase as much as 25PSI in addition to the change in ambient, if I remember his post.

In post #7 of this thread Elan states that the IP increases from 130 to 155 psi. So the IP is only increasing about 50% of the increase in ambient pressure.

 

[elan]

In post #7 of this thread Elan states that the IP increases from 130 to 155 psi. So the IP is only increasing about 50% of the increase in ambient pressure.

markr, we do not worry about the ambient pressure here as it will affect both second and first stage and as halocline stressed it for that reason we think about the IP in PSI relative to the ambient pressure.

the figure I gave is the data I found on how much the relative IP increases on top of increase due to the depth.