O2 transfill whip

[Packhorse]

Just a thought.....


Supose you want to transfill a RB O2 rebreather tank from a larger tank instead of using a whip with a needle valve how about a whip with a fixed oriface to reduce the flow rate?

Following on from a DIY thread how about just using 2 1st stages and a HP hose between them to transfill O2? The small oriface in the 1st stages will reduce flow rates.

Any thoughts? (yeah I know its better to just get a propper whip)

 

[Jimmer]

I supposed a snubber installed inline would be help. But with the cost you can buy needle valves for, why bother?

 

[skippy31]

People have been using the large tank valve to control the flow rate of the gas for years. This does not mean this is the recommended way to do this though. Trans-fill whips have come down in price a lot over the years, so there is not really a good reason not to use one or to try to jerry rig something.

A pressure gauge is also important to be able to judge the flow rate....

Mat.

 

[Rick Inman]

Don't forget to add a pressure release (purge) of some sort, or your regs will be locked.

Really, two O2 clean first stages, a gage, and purge valve... I just can't see the savings over a proper whip.

 

[Packhorse]

Don't forget to add a pressure release (purge) of some sort, or your regs will be locked.

Really, two O2 clean first stages, a gage, and purge valve... I just can't see the savings over a proper whip.

The savings come form the fact that I already have all that. The purge is a 2nd stage. The gauge is a SPG

Not that I am going to do it that way ( I have been doing it with air for years).

It just seems to me that a snubber is 1/10 the price of a quality needle valve and you will never ever have the problem of excessive flow.

 

[oxyhacker]

An orifice will drive you crazy eventually because the flow rate will vary so much with pressure, that if you pick a size that gives you a safe rate with a high delta-P you will find yourself doing foolish things like jiggling the supply tank to try to speed things up when it gets low.

With a needle gauge you can fine tune the flow to be safe but not too tedious. And they just aren't all that expensive, bought on ebay especially.

 

[Jimmer]

An orifice will drive you crazy eventually because the flow rate will vary so much with pressure, that if you pick a size that gives you a safe rate with a high delta-P you will find yourself doing foolish things like jiggling the supply tank to try to speed things up when it gets low.

With a needle gauge you can fine tune the flow to be safe but not too tedious. And they just aren't all that expensive, bought on ebay especially.

I agree, the snubber will be a pain when the delta is low. As for the ebay thing, I bought 4 brass, 3000psi needle valves on ebay for $40.