Tank to tank fill?

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I'm cheap, so I use a variation on the @couv method ( Tank Equalizer for $2.50 )
I just use a spare air fil adapter I had laying around instead of a 2nd first stage.

If ya want to be really cheap and get a wee bit of positive pressure just tightly hold the values face to face.
 
Hi All, I recently was certified to do tank visual inspections. I have quite a few tanks and economically it made sense. My question is that I don’t want to leave my tanks empty to long after an inspection and getting them filled right away isn’t always an option. My idea is to use what I believe to be called a whip and add air from a full tank to a empty tank. Has it does anyone currently do this?

I do that . my reason is that since the tank has been opened it now has a higher humidity than normal. I fill to say 500 psi and then vent it down with dry compressor or other tank air. 500 psi is about 33 bar so after venting the contents are now 3% the humidity of what it was when just installing the valve. another cycle of this leaves you with functionally no atmosphere air that has not been filtered.
 
I'm cheap, so I use a variation on the @couv method ( Tank Equalizer for $2.50 )
I just use a spare air fil adapter I had laying around instead of a 2nd first stage.

Respectfully

James
Good Morning James, when I follow the like in That post to grainger it shows a 1/4 inch fitting. I searched on their site for a 7/16 but am coming up empty.
 
actually i do cover this in my vip class, as alot of lds dont like an empty tank so i teach then to put in 200- 500 psi in a tank
 
Good Morning James, when I follow the like in That post to grainger it shows a 1/4 inch fitting. I searched on their site for a 7/16 but am coming up empty.
I believe this is the correct one for hp hose to hp hose connection...As I understand it, the size is based off hose size rather than wrench size. Due to a quirk of my fill adapter, I didn't actually need a union, so @couv would be better able to answer.

Respectfully,

James
 
I think that's the first time I've seen my calculator shared by someone else :) Made my day Rob, thank you!

I really enjoy thinking through things, but math is not my strong suit and I don't care to do it every time. I think it's important to understand the principles so you can make sure your answers are in the ballpark, but one of the ways to keep people doing something is to make it easy. Same thing with checklists, they have to be easy or else people discard them.

Anytime someone has given me a calculation question, I have tried to take the time to build the calculator for it so I can answer it faster in the future.

I like the web interface for your calculator. I built a simple calculator on Google Sheets that does the same thing without the pretty interface.

One suggestion I would make for your calculator, though, is to take into account not only the rated volume of the cylinders, but the rated pressures also. For example, if you're transfilling from an HP100 to an LP95, every 100psi drop on the HP100 (or 2.9 cuft of gas transferred) is only going to raise the pressure on the LP95 by about 80psi due to the larger water volume of the LP tank.
 
One suggestion I would make for your calculator, though, is to take into account not only the rated volume of the cylinders, but the rated pressures also. For example, if you're transfilling from an HP100 to an LP95, every 100psi drop on the HP100 (or 2.9 cuft of gas transferred) is only going to raise the pressure on the LP95 by about 80psi due to the larger water volume of the LP tank.

Doh! You are correct, I thought I understood this principle but I clearly did not! I have updated the calculator but I borrowed from the dissimilar tank matching calculator, it's at the bottom of the page. The incorrect calculation is still in there, just scroll past it to the very bottom!

Please test it out and see if it works well, and let me know if you prefer selecting radio button for which tanks, or if it would be better to type in the tank nominal cf and rated pressure. Could be there are too many tank options in the world, but I also wanted to make it friendly.

Gas Planning

By the way, Phoque was the user who first pointed out this error, and I proceeded to make the exact same error again when building the calculator... not the teachers fault that the student didn't comprehend well! Here's that post:
Filling double LP 50's from a HP 120
 
I believe this is the correct one for hp hose to hp hose connection...As I understand it, the size is based off hose size rather than wrench size. Due to a quirk of my fill adapter, I didn't actually need a union, so @couv would be better able to answer.

Respectfully,

James

I do not see one at the Grainger nor (gasp) McMaster web sites. Here is an example and a vendor of the fitting needed.

https://www.newegg.com/eaton-202702-4-4s/p/26V-0004-002D2?cm_re=Hose_Adapter,_SAE_to_JIC,_Straight-_-26V-0004-002D2-_-Product#
 
I believe this is the correct one for hp hose to hp hose connection...As I understand it, the size is based off hose size rather than wrench size. Due to a quirk of my fill adapter, I didn't actually need a union, so @couv would be better able to answer.

Respectfully,

James

I do not see one at the Grainger nor (gasp) McMaster web sites. Here is an example and a vendor of the fitting needed.

https://www.newegg.com/eaton-202702-4-4s/p/26V-0004-002D2?cm_re=Hose_Adapter,_SAE_to_JIC,_Straight-_-26V-0004-002D2-_-Product#

I received my fitting today and was able to configure my whip. It works wonderful. Thanks for all the info.
 
Wow nicely done! I like your way much better than my way. A while back I was trying to make a cheap one so I bought two of these 7/16" to 1/4" NPT OmniSwivel Adapter: 1/4-Inch NPT Male = 7/16-Inch F and took a 1/4" male to male NPT hydraulic hose from work and connect two reg together like this. Cost me $30 obviously your way is a little more clever than my way.

Yep you will need a hand full of male and female JIC's if you are going to do this stuff. It makes the world of compressors a lot more congenial
 
https://www.shearwater.com/products/teric/

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