PSA for compressor owners



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Offline BEN342R

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Re: PSA for compressor owners
« Reply #20 on: November 28, 2017, 09:01:32 AM »
[quote author=Joe Brancato link=topic=84327.ms

Our air doesn't have to be exactly breathable (odors, carbon dioxide ok), but it must be dry. The problem is that neither the Diablo nor Joe's have any kind of technical data so judging their effectiveness is difficult.
[/quote]

Sloth, Don't know your real name, but thank you for the link. I have also written on how a PROPER and SAFE filter MUST be made. NO LOOSE BEADS should ever be used, as the media will leach acid and eventually cause a weakening of pressure vessel.


1) One must use Molecular Sieve (not beads");  Molecular Sieve is recognized in the industry as being the "best", it is used in almost all breathing filters and other types of high pressure filters where one needs to "scrub" the air.

2) High pressure filters work best at.......High Pressure. When filling a high pressure tank with an inline filter, ensure the filter has some kind of valving mechanism that allows the pressure to build up prior to flow through the filter.  Filter media needs a "dwell time" as well as high pressure to work best. Simply running air through a cylinder with a filter element doesn't work well. Make sure the filter has the proper valving to allow pressure to build up before the air runs through it. without the valving, the air and moisture basically rushes over the media at low pressures, and doesn't get scrubbed. The pressure needs to be held back up to a point, and then allowed to flow.

3)  One can't just pack beads in a cylinder for 2 VERY important reasons.
A) It doesn't work :  We'd all like to just make a filter that uses cheap beads packed in a cylinder, but the first issue is that without proper packing, "channeling" will occur between the media. Simply put, channeling is the situation where air just goes around the individual filter "beads" instead of being "scrubbed". In order to work, the media need to be properly "jam packed" into the a container element, and this filter element put in a filter tube. An element can be manufactured to be "jam packed". Putting the media into a tube doesn't pack it tight enough to prevent channeling at high pressures. Filter elements are rather inexpensive, so it isn't an issue.

B) Most importantly SAFETY.   NEVER make a high pressure filter where the filter material directly touches the cylinder walls of a high pressure filter. This is filter element 101. The moisture in filter media leaches acid, and hence must not come in direct contact with the filter tube. Acid that leaches out will eventually make it to the threads on the end-caps of the filter, weakening them, and eventually causing the high possibility of catastrophic failure. This point can't be stressed enough. 4) I have left out some of the more obvious points, such as ensure your tubing can handle the pressure and is from a reputable source.
[

Joe- I have some questions about your alpha filter not explained in your link.  My goal is to get clean dry air for safety and get the maximum service life out of my tanks and rifles without getting my face fragged  off-ha and trying to learn too. 
1)is the valve on your alpha filter considered a PMV?
2)If so I is it adjustable and if not what is the set point before it allows the air to start trickling through? 
3)does the filter have any additional elements to the MS beads?
4)how do I service this?  My compressor flows 50L/min.
5)what do replacement filter cartridges cost? 
6) I already bought a Diablo type filter would you be willing to sell me a PMV alone
I realize I could call but may help others by asking here in the same boat.
Thanks in advance Joe for the knowledge and time
« Last Edit: November 28, 2017, 09:04:04 AM by BEN342R »
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Offline Kinetic45^

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Re: PSA for compressor owners
« Reply #21 on: November 30, 2017, 03:19:28 AM »
Hot compressed raw air holds LOTS more water than regular temperature air. And even a 40% humidity day is a lot of water for HPA systems!  So first cooling the compressed air so condensate comes out and then separating that water with a mechanical 'sump' is what you should do BEFORE the compressed gasses go to your desiccant/molecular sieve.

When I do the compressed air route (mostly I use N2) I PRE run my air through a 100 psi shop compressor whose output goes into a 50 foot 3/8 copper line coiled up in a tub of water n antifreeze inside a minibar refrigerator I bought for less than $100.00  {  2.6 cu-ft-mini-fridge-black  $69.99 }  I drilled two holes in the side of the fridge for the lines to I/O.  The output cold air goes into a vertically mounted 2" galvanized pipe 48' long which has a reducer on the bottom and a drain valve.  Up top there is a reducing Tee where the cold air and condensate come in and above that a nipple and reducer where the 'mostly dried' outlet air then goes to my homemade dryer cylinder w/ sieve and then to my my booster.  Note: you DO have to have the water PRE-CHILLED prior to starting a run for this to work - just plug in the frig the day before.  I keep thinking about putting in a sight glass but I do OK just draining the sump every few hours.

I had a lot less internal tank and valve corrosion problems in my QB's and others brands than I did when I was using my Hill pump ( whose filter lasts about FOUR rifle fills for a BAM XS-51 on 99% humidity Texas summer days ).  Real easy to tell, buy an inline moisture sensor from an AC Supply and you can tell when the filter is full because the color changes.
« Last Edit: November 30, 2017, 03:25:24 AM by Kinetic45^ »
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Offline prfssrlee

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Re: PSA for compressor owners
« Reply #22 on: December 11, 2017, 12:07:58 AM »
Hi everyone,

I am new to PCP AGs and to this forum. I have Yong Heng compressor on order and was intending to put a Campbell Hausfield dryer system on the *inlet* side - that's my intention assuming the inlet port is threaded. I couldn't tell from any of the youtube videos (I watched about 6 or 8 of them and never got a clear shot of the intake port). Anyway, I got such a good deal on the compressor ($179 + free shipping from walmart about 10 days ago) and figured the inlet dryer/filter system was worth buying. I've used them before in my lab and they work pretty well. We've noticed that they are most effective at dessicating when the air flow is low like in this application on the inlet side (and you remember to cap it off when not in use). To do better on the inlet side, one has to go to much greater lengths, as Kinetic45^ describes. I do have a spare 2.5kW Neslab recirculating chiller in the lab, but I don't think my students would appreciate me bringing it home to pre- and post-chill the compressor air into my synrod. ;-)

However, like I said I am a complete newbie to PCP airguns and I know this topic of water removal from compressed air has been hashed over many times - I looked on the forum and couldn't find any discussion about inlet dessication (rcontreras mentions it briefly below but that's all I found), so now I wonder if I am missing something obvious about why that isn't useful to do. I have one of those big gold tubes on order for the outlet side going in to the gun/tank - but why doesn't everyone run the inlet air through a dryer before compressing it as a sinple first step in minimizing moisture in the system?

Thanks for your advice - sorry if this is a stupid question but for the life of me, I can't figure out why I shouldn't do that.

-david
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Offline prfssrlee

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Re: PSA for compressor owners
« Reply #23 on: December 11, 2017, 12:57:44 AM »
Hi again everyone,

Sorry to ask another question so quickly after the previous post... I also happen to have a small air brush compressor sitting unused which can output something like 40-45 psi. It's not alot of volume (or pressure), maybe 20-25 lpm (0.7-0.9 cfm) - but I am wondering whether it would be worth sticking that on the inlet to the Yong Heng in front of the dryer/filter system I ordered.

Basically, I guess I'm asking if anyone has run their Yong Heng compressor as a booster - 45psi isn't much input pressure, but it should still speed up the fills and reduce the temperature of the 3rd stage a fair amount (I guess we could do that calculation to see how much), thereby reducing the heat load on the aquarium pump and water recirc bucket. It might even give a person a bit more time to turn it off in case the water pump fails. I think I've read a few stories about that happening.

So if I did this, the system would look like: inlet at 14.7 psi --> air brush compressor --> 45psi @ 0.8cfm --> dryer/filter system --> (possibly a needle valve or other throttle valve if 0.8cfm is too high a flow rate) --> Yong Heng --> gold tube filter/separator --> cylinder fill to 4500psi (or output to tank on synrod and stop at 3000psi).

So an additional question to those above concerns the intake rate for the Yong Heng compressor. Oh right, it's calculable based on the output rate and the compression ratio, but it's 11:45pm here and I am getting sleepy. Unless anyone happens to know, I'll figure it out tomorrow...

Couldn't stand it - looked on amazon really quick to find a product description that says it fills "1 liter at 300 bar in 12 minutes". That's 300 liters of air at 1 atmosphere in 12 minutes or 16.7 lpm = .6 cfm (assuming it loads up linearly, which is probably wrong). Hey, the numbers are close! Close enough to do the experiment at some point in the future maybe.

Again, hope my questions are not too "newbie" - I admit to being bitten by this whole PCP AG thing. Sorry that my questions reflect an almost total lack of knowledge. These forums are a great way to learn, and being wrong is part of that process. In any event, it is way more fun thinking about this than grading exams or preparing lectures.

-dave
  • Wenham, MA. USA.

Offline chwillbill68

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Re: PSA for compressor owners
« Reply #24 on: February 18, 2018, 03:43:42 PM »
[quote author=Joe Brancato link=topic=84327.ms

Our air doesn't have to be exactly breathable (odors, carbon dioxide ok), but it must be dry. The problem is that neither the Diablo nor Joe's have any kind of technical data so judging their effectiveness is difficult.

Sloth, Don't know your real name, but thank you for the link. I have also written on how a PROPER and SAFE filter MUST be made. NO LOOSE BEADS should ever be used, as the media will leach acid and eventually cause a weakening of pressure vessel.


1) One must use Molecular Sieve (not beads");  Molecular Sieve is recognized in the industry as being the "best", it is used in almost all breathing filters and other types of high pressure filters where one needs to "scrub" the air.

2) High pressure filters work best at.......High Pressure. When filling a high pressure tank with an inline filter, ensure the filter has some kind of valving mechanism that allows the pressure to build up prior to flow through the filter.  Filter media needs a "dwell time" as well as high pressure to work best. Simply running air through a cylinder with a filter element doesn't work well. Make sure the filter has the proper valving to allow pressure to build up before the air runs through it. without the valving, the air and moisture basically rushes over the media at low pressures, and doesn't get scrubbed. The pressure needs to be held back up to a point, and then allowed to flow.

3)  One can't just pack beads in a cylinder for 2 VERY important reasons.
A) It doesn't work :  We'd all like to just make a filter that uses cheap beads packed in a cylinder, but the first issue is that without proper packing, "channeling" will occur between the media. Simply put, channeling is the situation where air just goes around the individual filter "beads" instead of being "scrubbed". In order to work, the media need to be properly "jam packed" into the a container element, and this filter element put in a filter tube. An element can be manufactured to be "jam packed". Putting the media into a tube doesn't pack it tight enough to prevent channeling at high pressures. Filter elements are rather inexpensive, so it isn't an issue.

B) Most importantly SAFETY.   NEVER make a high pressure filter where the filter material directly touches the cylinder walls of a high pressure filter. This is filter element 101. The moisture in filter media leaches acid, and hence must not come in direct contact with the filter tube. Acid that leaches out will eventually make it to the threads on the end-caps of the filter, weakening them, and eventually causing the high possibility of catastrophic failure. This point can't be stressed enough. 4) I have left out some of the more obvious points, such as ensure your tubing can handle the pressure and is from a reputable source.
[

Joe- I have some questions about your alpha filter not explained in your link.  My goal is to get clean dry air for safety and get the maximum service life out of my tanks and rifles without getting my face fragged  off-ha and trying to learn too. 
1)is the valve on your alpha filter considered a PMV?
2)If so I is it adjustable and if not what is the set point before it allows the air to start trickling through? 
3)does the filter have any additional elements to the MS beads?
4)how do I service this?  My compressor flows 50L/min.
5)what do replacement filter cartridges cost? 
6) I already bought a Diablo type filter would you be willing to sell me a PMV alone
I realize I could call but may help others by asking here in the same boat.
Thanks in advance Joe for the knowledge and time
[/quote]

  Thanks for asking these questions, I would love to know the answers also.  I have been ready so many different threads trying to figure out the best way to keep water out for the cheapest amount and not killing my budget!  I love it when folks post pic's of what they use and where they bought them.
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Offline FamilyMan811

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Re: PSA for compressor owners
« Reply #25 on: February 18, 2018, 06:35:54 PM »
Maybe a better way of approaching this is to get tank manufactures to line the inside of their tanks with something that stops corrosion before it can start.



+1
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Offline Kinetic45^

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Re: PSA for compressor owners
« Reply #26 on: February 18, 2018, 08:13:05 PM »
Maybe a better way of approaching this is to get tank manufactures to line the inside of their tanks with something that stops corrosion before it can start.

+1

This is what I use on my tanks since I learned about it as an aircraft mechanic A&P - Alodine

Here is a link to the wiki explaining about the treatment, copy/paste n close the gaps since i con't post direct links

ht  tps://en.wikipedia.    org/wiki/Chromate_conversion_coating

I treat the tanks right after hydro or purchase new and have peace of mind that if any moisture gets to my tanks there is some protection inside instead of bare aluminium (note, I would not treat scuba or scba tanks without marking them so no one ever tries to use for breathing air.)

Can order it form aircraft supply stores easily, no permit or license required.

The reason mfgs do not line tanks with 'slosh' is that it might hide a pinhole in the coating where corrosion could grow underneath and go undetected during the visual inspection part of the re-certification process.  Alodine is translucent and does not hide a spot.

I have used slosh on motorcycle tanks with pinholes and old car restorations but would never use in a pressure vessle.
slosh is : ht   tp://www.aircraftspruce.    com/catalog/appages/bunan.php?gclid=EAIaIQobChMIjN_x7Nmw2QIV2BCBCh3WVgE9EAYYASABEgLP6vD_BwE
« Last Edit: February 18, 2018, 08:19:20 PM by Kinetic45^ »
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