Haskel AG-75 experiences ?
- Thread starter Segs14
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the risk with the AG75 is the boost ratio. The AG30's are standard because at 30:1, you never really get dangerous with drive gas. Regulators are typically 135psi->4050psi stall pressure. Most home air compressors stop at 120psi->3600psi. With Oxygen you want to avoid going that high, but you will never really get in trouble with the boost ratio.
With the AG75, you need to make sure that you have ideally a pressure cutoff switch feeding the drive gas, as well as really good drive gas regulator, and you can't really run it off of a scuba tank since you need it to cut off at 50psi maximum, 40psi for oxygen, you also need to make sure you have a properly set OPV on the outlet. That gets really twitchy with regards to trying to stall the pump at the right pressures. If the deal is good enough, then go for it, just be very careful when boosting and make sure you're always paying attention so you don't blow something up. That booster is rated to pump to over 11,000psi, and on a scuba regulator, it WILL pump that high.
With the AG75, you need to make sure that you have ideally a pressure cutoff switch feeding the drive gas, as well as really good drive gas regulator, and you can't really run it off of a scuba tank since you need it to cut off at 50psi maximum, 40psi for oxygen, you also need to make sure you have a properly set OPV on the outlet. That gets really twitchy with regards to trying to stall the pump at the right pressures. If the deal is good enough, then go for it, just be very careful when boosting and make sure you're always paying attention so you don't blow something up. That booster is rated to pump to over 11,000psi, and on a scuba regulator, it WILL pump that high.
Use to using a 15/30 at a dive shop. So the high pressure thing isn’t my main concern. I also never leave a tank unattended when boosting. I was thinking of running it off of some Banked gas with it own output regulator. I do see what you mean about the 11000 possible output and safety if you don’t put a proper regulator on it.
based on the pump ratio it should be able to really pump down a O2 or He cylinder?
based on the pump ratio it should be able to really pump down a O2 or He cylinder?
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@Segs14 a 15/30 isn't a high pressure pump though. Those won't run over 4500psi because the stall ratio is 30x drive gas and it is only rated for 150psi drive. With the AG30, I have no problem letting it run non-oxygen without me watching because the compressor that I have driving it can only get up to 125psi so it stalls below 4000psi. When I run O2, I set the outlet regulator at 100psi and just let it go until it stops. The regulators are much more stable knocking 125psi down to 100psi than 125 down to 40. If the reg fails, and lets all 125psi through, the difference between 100 and 125psi is also only 700psi and while I would rather not have O2 pumped to 3700psi, I'm much less concerned about a fire with as slow as it runs than I would be with an AG75 where that I need it to stop at 40psi and if it even gets to 50psi, that's the same 3700psi outlet, but if the reg fails and gets to 100-125psi, you'll need the OPV to be working properly to prevent a serious issue.
The 75 is a different beast. If you're running off of bank bottles, you will actually need a pair of regulators. One to knock it down to something reasonable like 100-200psi, then another one to drop it to 40-50psi. You can't trust a regulator that's knocking 4000+psi down to 40-50psi to be stable and if you have IP creep, you're f*cked.
Per the spec sheet, it will scavenge down to 250psi of supply gas. That's vs 100psi for an AG30, and 50psi for the 15/30. That said, you have to pay attention to the compression ratio of O2 in particular and when you get down to that low of a supply, you have to pump into intermediate bottles. I.e. 250psi boosted to 3000psi is dangerous and should always go into an intermediate cylinder at 1500ish psi, then that be boosted again to 3000psi.
If you're getting a screaming deal on the AG75, then go for it, but it comes with a LOT more risk than boosters with max outlet pressures and drive ratios better suited to the gases that we are pumping.
The 75 is a different beast. If you're running off of bank bottles, you will actually need a pair of regulators. One to knock it down to something reasonable like 100-200psi, then another one to drop it to 40-50psi. You can't trust a regulator that's knocking 4000+psi down to 40-50psi to be stable and if you have IP creep, you're f*cked.
Per the spec sheet, it will scavenge down to 250psi of supply gas. That's vs 100psi for an AG30, and 50psi for the 15/30. That said, you have to pay attention to the compression ratio of O2 in particular and when you get down to that low of a supply, you have to pump into intermediate bottles. I.e. 250psi boosted to 3000psi is dangerous and should always go into an intermediate cylinder at 1500ish psi, then that be boosted again to 3000psi.
If you're getting a screaming deal on the AG75, then go for it, but it comes with a LOT more risk than boosters with max outlet pressures and drive ratios better suited to the gases that we are pumping.
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