I actually JUST got an email back from a sales rep for a company in Norway that sells hose mostly for the aerospace industry (as far as I can tell). They have a 3" silicone-coated aramid fiber hose that weighs in at 680 grams per meter (less than half the weight of typical PVC pumpout hose) and is rated for 25 inHg which, as I understand, is within the requirements since many pumps actually only go to 18 inHg, though better peristaltic pumps do promise vacuum closer to the 29 to 29.5 range.
(For anyone who cares and doesn't know, "standard" pressure at sea level is 29.92 inHg. These pumps are rated as to how much of that pressure they can "remove". So, a perfect vacuum would be 29.92 inHg. In practice, this can't be achieved, so there is really no such thing as a "full vacuum" pumpout station. But, the better ones are close enough, with pumps that promise getting to 29.5 inHg under ideal conditions. When they describe a pump as rated to 29.5 inHg, they really mean the relative measurement of -29.5 inHg ... or 29.5 inHg lower than the ambient pressure under standard conditions.)
This hose has a minimum bend radius of 2.5", meaning the hose would make a 180 degree bend in 11". That's pretty flexible. I don't know, but would estimate that the hose I am used to seeing has a minimum bend radius of about twice that.
The rep pointed out that, likely, the only reason this would not be suitable for a pumpout station is because the hose is not coated for UV protection. But, UV protection is pretty easy, so surely a similar hose with UV protection either exists or could exist. I just started looking. So, the fact that this one company (the first to respond to me) has something so close to what I am looking for ... that's encouraging. They want about $50/ft, which doesn't seem cost-prohibitive.
(For anyone who cares and doesn't know, "standard" pressure at sea level is 29.92 inHg. These pumps are rated as to how much of that pressure they can "remove". So, a perfect vacuum would be 29.92 inHg. In practice, this can't be achieved, so there is really no such thing as a "full vacuum" pumpout station. But, the better ones are close enough, with pumps that promise getting to 29.5 inHg under ideal conditions. When they describe a pump as rated to 29.5 inHg, they really mean the relative measurement of -29.5 inHg ... or 29.5 inHg lower than the ambient pressure under standard conditions.)
This hose has a minimum bend radius of 2.5", meaning the hose would make a 180 degree bend in 11". That's pretty flexible. I don't know, but would estimate that the hose I am used to seeing has a minimum bend radius of about twice that.
The rep pointed out that, likely, the only reason this would not be suitable for a pumpout station is because the hose is not coated for UV protection. But, UV protection is pretty easy, so surely a similar hose with UV protection either exists or could exist. I just started looking. So, the fact that this one company (the first to respond to me) has something so close to what I am looking for ... that's encouraging. They want about $50/ft, which doesn't seem cost-prohibitive.