Stainless steel hardline tubing project.

[Ty Hamby]

Getting ready to start my next project and I have a few question about stainless steel hardline tubing construction. I have banked air at 4500 psi. I would like to relocate my bank to a separate area from the compressor. I would also like to construct a regulator service bench with supplied banked air into a first stage bench stand.
My questions are:
1) what diameter tubing is ideal for this project? 1/4, 5/16, 3/8?
2) how thick should the tubing be? .049?
3) what fittings would you recommend? Other than Swagelok
4) reliable source for fittings and tubing?
5) Do I need anything more than shutoff valves in the line? Check valves, regulators, ect?

I have never bent tubing before and knowing stainless steel thick tubing will be difficult I have decided to skip all the knock off benders and stick with swagelok tool. I know it will be pricey but cost is less of and issue than quality construction for this project. Teaching myself a new skill along with the knowledge gained is the priority here. In the end I will end up with my compressor relocated away from the work area with my fill station and workbench conveniently located in my workshop.

 

[Asheron]

3) gyrolok
4) Ebay

 

[TrimixToo]

Getting ready to start my next project and I have a few question about stainless steel hardline tubing construction. I have banked air at 4500 psi. I would like to relocate my bank to a separate area from the compressor. I would also like to construct a regulator service bench with supplied banked air into a first stage bench stand.
My questions are:
1) what diameter tubing is ideal for this project? 1/4, 5/16, 3/8?
2) how thick should the tubing be? .049?
3) what fittings would you recommend? Other than Swagelok
4) reliable source for fittings and tubing?
5) Do I need anything more than shutoff valves in the line? Check valves, regulators, ect?
dsf
I have never bent tubing before and knowing stainless steel thick tubing will be difficult I have decided to skip all the knock off benders and stick with swagelok tool. I know it will be pricey but cost is less of and issue than quality construction for this project. Teaching myself a new skill along with the knowledge gained is the priority here. In the end I will end up with my compressor relocated away from the work area with my fill station and workbench conveniently located in my workshop.

I just found something with the right approximate diameter (somewhat smaller than what the shape had to be at the end) and bent the tubing around it. Worked great.

 

[Tracy]

1) what diameter tubing is ideal for this project? 1/4, 5/16, 3/8?
2) how thick should the tubing be? .049?
3) what fittings would you recommend? Other than Swagelok
4) reliable source for fittings and tubing?
5) Do I need anything more than shutoff valves in the line? Check valves, regulators, ect?

1. .250 will be more than adequate for anything but the busiest of commercial fill stations

2. .035 is much easier to work with and is rated for 5250psi. You can use 049 with no ill effects outside of it being much harder to bend and flare. .049 has become the current standard as most new fill stations are being built for 6-7000 psi instead of 4500. Scuba has stayed with 4500 as it is cheaper and still gives a good pressure gradient for most tanks.

3. I flare everything to JIC, it is cheaper and makes swapping between tube and hose very easily. It would require you to purchase a flaring tool so if you are only doing 10-20 fittings, compression fittings would be cheaper.

4. If you want 20' lengths, you will need to source it locally from an industrial supply house of some kind. It is the easiest to work with and gives the nicest finished look. If you don't mind coiled tube, you can find remnant rolls very affordably on ebay.

5. I tend to use the valves already on the tanks and don't add anything inline on the tubing. That is just personal preference. If you are adding inline shutoffs, make you life easier and spend the extra $9 per valve for 1/4 turn.

 

[Ty Hamby]

1. .250 will be more than adequate for anything but the busiest of commercial fill stations

2. .035 is much easier to work with and is rated for 5250psi. You can use 049 with no ill effects outside of it being much harder to bend and flare. .049 has become the current standard as most new fill stations are being built for 6-7000 psi instead of 4500. Scuba has stayed with 4500 as it is cheaper and still gives a good pressure gradient for most tanks.

3. I flare everything to JIC, it is cheaper and makes swapping between tube and hose very easily. It would require you to purchase a flaring tool so if you are only doing 10-20 fittings, compression fittings would be cheaper.

4. If you want 20' lengths, you will need to source it locally from an industrial supply house of some kind. It is the easiest to work with and gives the nicest finished look. If you don't mind coiled tube, you can find remnant rolls very affordably on ebay.

5. I tend to use the valves already on the tanks and don't add anything inline on the tubing. That is just personal preference. If you are adding inline shutoffs, make you life easier and spend the extra $9 per valve for 1/4 turn.

I like all of your advice. I appreciate greatly the time you took to answer all my questions clearly. I will take your advice on the .035. I will never be doing pressures beyond 4500 until the standards in scuba changes. The same scuba that still promotes yoke tank valves.

 

[happy-diver]

Let me also do it right for you sir!

Tubing

Always look beyond where you are

 

[rjack321]

5) Do I need anything more than shutoff valves in the line? Check valves, regulators, ect?

I have in line valves to my banks. 7 different bottles at multiple pressures

You dont need check valves or regulators

 

[TrimixToo]

I have in line valves to my banks. 7 different bottles at multiple pressures

You dont need check valves or regulators

Nope. But those automatic cascade valves would be the cat's ass!

 

[Ty Hamby]

Nope. But those automatic cascade valves would be the cat's ass!

Much like scuba, maintaining a cylinder fill station is just as much a hobby. We can't give all the duties away to nifty technology. What would be left for me to screw up?

 

[Tracy]

Nope. But those automatic cascade valves would be the cat's ass!

You can make your own pretty easily with PMVs. They are only $79 each new from Bauer