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"High Flow" 3/8" ID Air Hose ?

Outahere

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Is there such a thing? I recently bought some Milton high flow 1/4NPT quick disconnect couplings and a 25ft Flexzilla 3/8 ID air hose with 1/4"NPT male fittings crimped on each end. About a 1/2" in from the end of each fitting is a short 0.27" restriction. I'm just curious if there are 3/8 air hoses that have larger bore "high flow" crimped on 1/4NPT fittings. I checked the Milton website for a high flow 3/8 hose and found nothing.

A reviewer on Amazon wrote he noticed a performance difference between his new 3/8 BluBird air hose with a restriction of 0.281" versus his old 3/8 Tekton hose, which has a restriction of 0.266". He also measured the restriction on a Milton high flow 1/4NPT coupling to be 0.277".
 
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GeoBruin

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I'm sure if you shop around looking at the ID of various hoses you will find some variability, but I'm not aware of a dedicated "high flow" hose. The reality is that restriction is going to be truly negligible (I mean truly, I'm not talking a few cfm here, I'm talking 1ish) within the context of a whole system of fittings and at the pressures and flow rates you're working with).

And I'm not blowing smoke. I have conducted multiple tests (all of which I've recorded and posted here on this forum) of various air fittings with different orifice sizes under different pressure and flow scenarios. I applaud you trying to eek every bit of performance out of your air system, but you're not likely to recover much performance in this particular area.
 

Lucid Moments

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I am going to tag onto this thread. I have 50' hoses, but rarely ever use even half of them. How much better flow can I get if I cut them in half and put new ends on them?
 

GeoBruin

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I am going to tag onto this thread. I have 50' hoses, but rarely ever use even half of them. How much better flow can I get if I cut them in half and put new ends on them?
At what static pressure and flow rate do you plan to use them? At low pressures and/or low flow rates, the differences are negligible. At higher pressures and flow rates, the differences are meaningful.

Let's assume a scenario where you have a tool that needs 90 psi at the tool and consumes 30 cfm at 90 psi.

With a 50' 3/8" hose, you'll need to have your regulator turned up to 119 psi to get the desired 90 psi at the tool.

With a 25' 3/8" hose, you'll be able to set the regulator 20 psi lower (99 psi) and still see 90 psi at the tool.

But run the same numbers assuming your tool only consumes 10 cfm. Even with a 50', 3/8" hose, you would only need to set your reg to just over 92.5 psi, compared with just 91.5 for a 25' 3/8" hose.
 
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Jswain

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I am going to tag onto this thread. I have 50' hoses, but rarely ever use even half of them. How much better flow can I get if I cut them in half and put new ends on them?
If you have a 2 stage compressor it is little benefit. However if you have a single stage that maxes out ~125psi then it might make a worthwhile difference, especially if you use IR or snap on or other air hungry impact guns.
 
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Lucid Moments

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At what static pressure and flow rate do you plan to use them? At low pressures and/or low flow rates, the differences are negligible. At higher pressures and flow rates, the differences are meaningful.

Let's assume a scenario where you have a tool that needs 90 psi at the tool and consumes 30 cfm at 90 psi.

With a 50' 3/8" hose, you'll need to have your regulator turned up to 119 psi to get the desired 90 psi at the tool.

With a 25' 3/8" hose, you'll be able to set the regulator 20 psi lower (99 psi) and still see 90 psi at the tool.

But run the same numbers assuming your tool only consumes 10 cfm. Even with a 50', 3/8" hose, you would only need to set your reg to just over 92.5 psi, compared with just 91.5 for a 25' 3/8" hose.

If you have a 2 stage compressor it is little benefit. However if you have a single stage that maxes out ~125psi then it might make a worthwhile difference, especially if you use IR or snap on or other air hungry impact guns.
I have a single stage compressor with a 60 gallon tank that puts out a max of 150 psi distributed through 3/4" maxline. There is a single filter/pressure regulator located just outside the compressor that is set to its max and shows a static pressure of around 140 psi. The 3/4" line continues to two air hose reels located on opposite sides of the shops. The hose reels each have 50' of 3/8" line and all my tools use Milton 1/4" V style fittings.

For the vast majority of what I use air for the system is perfect as far as I am concerned. I know that the single stage going to 150 psi is not idea, and the single pressure regulator isn't ideal either. But it works for my purposes. One time though with that setup my Astro Pneumatic Thor impact wrench didn't take the crank bolt off a BMW M20 engine I was working on. I hit the bolt with some PB Blaster and let it sit for an hour. When I went back it came off with no issues.

It may seem silly to make a change because of a single situation, but it is a pretty minor change so why not?
 

GeoBruin

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I have a single stage compressor with a 60 gallon tank that puts out a max of 150 psi distributed through 3/4" maxline. There is a single filter/pressure regulator located just outside the compressor that is set to its max and shows a static pressure of around 140 psi. The 3/4" line continues to two air hose reels located on opposite sides of the shops. The hose reels each have 50' of 3/8" line and all my tools use Milton 1/4" V style fittings.

For the vast majority of what I use air for the system is perfect as far as I am concerned. I know that the single stage going to 150 psi is not idea, and the single pressure regulator isn't ideal either. But it works for my purposes. One time though with that setup my Astro Pneumatic Thor impact wrench didn't take the crank bolt off a BMW M20 engine I was working on. I hit the bolt with some PB Blaster and let it sit for an hour. When I went back it came off with no issues.

It may seem silly to make a change because of a single situation, but it is a pretty minor change so why not?
The Thor is only advertised as requiring 6.8 cfm continuously. That's not going to cause a serious pressure drop, and if you're starting out way over pressured (140 psi static) you're probably seeing at least the advertised performance, if not more. If you really wanted to overdrive the wrench even more, you could shorten the hose (or use a half inch hose).
 

Lucid Moments

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The Thor is only advertised as requiring 6.8 cfm continuously. That's not going to cause a serious pressure drop, and if you're starting out way over pressured (140 psi static) you're probably seeing at least the advertised performance, if not more. If you really wanted to overdrive the wrench even more, you could shorten the hose (or use a half inch hose).
Which was exactly the question that started my entry into this thread.
 

GeoBruin

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Which was exactly the question that started my entry into this thread.
And I knew that, which is why I mentioned it as an option. But my point is, if the Thor will only consume 6.8 cfm, you have plenty of headroom to provide that (and then some) via dialing up your regulator. It's why my first question in response to your question was what pressure and flow parameters does your tool have? So we could determine whether you could achieve those with a longer hose or not.

If your question was simply "can I maximize my throughput by shortening my hose?", the answer, of course, is yes!
 

Jswain

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Yeah if you're starting with 150 then really no need. Turn up the pressure to whatever required to achieve 90+ at the tool
 

Spareparts

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I don't like Flexzilla hoses, I have only had 2 of them 3/8" 50' and both were are on hose reels, When I am done working I turn off the air supply,
drain the system, roll the hoses up. when I return to the shop turn the air supply on and I have a problem getting the hoses off the reels
because the flexzilla swells up pinching the hose. I know it is because of the way I do things that causes that problem. Changed the hoses out with hoses from TSC, blue hose with yellow stripe form TSC and no problem. I have got 6 drops in the shop all with 25' hoses and they have proven to be better air flow, less clutter,(don't trip over them as much) and a lot easier to wind up than a 50'. Enough for today, time to go to the shop and play.
 
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