Re: [PSUBS-MAILIST] Air compensating motors

[vbra676539@aol.com]

I was surprised that he did not have a ventilation system on board to relieve that pressure, or at least an expandable segment to inflate and deflate depending on the system requirements. Maybe they tried that. Air comp and electric motors is new to me. I know about it in the variable ballast systems on board JSL, but not on motors. The tygon tubing on Alec's oil filled motors seems to be flexible enough to do the trick here, or at least I haven't heard differently.

Vance

-----Original Message-----
From: Jon Wallace <jonw@psubs.org>
To: personal_submersibles <personal_submersibles@psubs.org>
Sent: Fri, Jan 27, 2012 11:02 am
Subject: Re: [PSUBS-MAILIST] Air compensating motors

Not a bad idea in terms of removing O2 from the system.  I was surprised to read Carsten's experiences with the oil expanding from the heat of motor operation given the excellent heat sink properties of water.

Jon


On 1/27/2012 10:47 AM, vbra676539@aol.com wrote:

Karl's experience, and the rust we saw when he tore down and overhauled the propulsion system on Idabel, suggests long-term dampness in the system, but whether from moisture buildup from air charges on his HP air or from minor seepage is hard to tell. I wonder if the use of nitrogen in a stand alone compensation system would be worth a try. And a slow, end to end system flush after diving. With no oxygen left in the system, rust would be held at bay, and the flush might warn you of excess moisture. Beyond that, it's hard to deny his experience. His system works. The oil comp does, too, so it gets back down to a choice.

Vance