GTA
Support Equipment For PCP/HPA/CO2 and springers ,rams => Support Equipment For PCP/HPA/CO2 => Topic started by: old sparky on March 03, 2018, 11:48:41 PM
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Just wanted to share my findings. I picked up my Omega Turbo Charger today. Before filling my air tank I thought I would check the moisture the compressor puts out and was surprised with the findings. The air I have been buying has been less than 20 PPMV moisture. Testing the compressor, the air coming out at 3000 psi is 119.3 PPMV or -43.5C ambient temp was 72 degrees f and 20% humidity. to wet to put in the tank. I was hoping for dryer air than that but now I know first hand.
Jim
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Jim, what device / method are you using to meausre the moisture content?
Thanks!
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Jim, what device / method are you using to meausre the moisture content?
Thanks!
A dew point meter by Xentaur. Its accurate. I need to choose a filter. If I can produce air less than 24 PPMV I will be satisfied. Interesting that vendors told me I didn't need a filter with this compressor. Lesson learned.
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What do you consider dry enough?
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A dew point meter by Xentaur. Its accurate.
yes, it is very accurate when calibrations are maintained. we have one at work thats portable.
its a very nice tool for our instrument techs, it should be....it cost over 5K $...... :o
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What do you consider dry enough?
First off I am not a authority on what is dry. I have been confused reading the forums with one saying you need filters and another saying you don’t. Thinking that I could get an answer to what is acceptable moisture. I ask by email Air Arms, Steyr, and Daystate. I didn’t get a number like I wanted. The best answer I got was breathing standards. I look up standards for diving air moisture and found, less than 24PPMV moisture. So I hoped for something close to 24. I bought a tank in 2010 and it has only had air from Sports Chalet until they closed then my local air gun dealer. I started my compressor and let it purge and come up to 3000 PSI then started the measuring the dewpoint the reading claimed exceeding 120 PPMV. I set the compressor to purge 5 minutes and let the compressor purge several times. Then retested getting the 119 PPMV. Then I wondered what my tank would read. I started reading the tank air when it got to 20.1 PPMV I stoped my test knowing that it was pretty dry air. I claim to know nothing about what is acceptable for PCP air. In my opinion I want my air down to the 24ish moisture level. So I will get a filter and go from there. I am confident the numbers I got are accurate numbers. I thought I would post this because not many have access to a dew point analyzer. Maybe no one else gets confused by advertisers claims but I do.
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I am very glad this discussion is happening because I have also been searching for this information. I have nothing concrete but I can share what I have found.
I first looked for at what humidity level will corrosion happen. I read in a couple places that above 50% corrosion would happen. Then I found this calculator online: http://www.dpcalc.org/index.php (http://www.dpcalc.org/index.php) It calculates the dew point from temperature and relative humidity. On the right it will give you a metal corrosion environment rating with "good", "ok" and "risk". It's the first hard dew point number when temperature and humidity are factored in that I have found. The dew point also changes with pressure. I think there was a calculator in one of Lloyd Sikes threads on how much water do compressors output. I will look for that thread and post the link when I do.
ADDENDUM: I found the thread: https://www.gatewaytoairguns.org/GTA/index.php?topic=128118.0 (https://www.gatewaytoairguns.org/GTA/index.php?topic=128118.0)
Another point I'd like to add is that breathing air is required to have some humidity as to not dry out diver's air passages. So I don't agree that the breathing standard humidity level is correct for air rifles or air cylinders.
We also need to be aware that our tanks and rifles accumulate moisture from refilling. I don't know of anyone who cleans out their tanks or air rifle reservoirs before they fill to start from zero moisture. Yes, some moisture is expelled as you shoot the rifle. But some moisture remains. So every time you fill a tank or air rifle you add more moisture that doesn't get removed. So you will end up with a certain level of water vapor and water condensate. While the water vapor may or may not be at a level to cause corrosion, the liquid water definitely will cause corrosion.
I have purchased the high pressure moisture indicator for my hpa setup but Jim, your measuring tool is cool!
I am glad to be having this conversation to bring awareness to the moisture issue and possible setup some guidelines to use.
Thank you,
Taso
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I am not an expert on humidity and it's affect on tanks or PCPs.... However, when you fill your gun from a tank, since the pressure drops, so does the humidity, in both your gun and the tank.... The "wettest" the tank will ever be, is right after you fill it and it cools down to whatever temperature you store the tank at.... I would think that as long as the compressed air in your tank is not saturated with water at your storage temperature.... and therefore NO liquid water condenses in the tank to cause corrosion.... you should be OK....
That would be the only thing that would concern me, anyways.... If your humidity in the tank is only 20% AT TANK PRESSURE (and I would be shocked if that was the case), then that is certainly VERY dry air.... If on the other hand you are taking a sample of that air, and measuring it's humidity at atmospheric pressure, then IMO it's pretty darn wet, because as you expand the air from the tank to atmospheric pressure the humidity drops quickly.... That is why when you SCUBA dive the air seems so dry, because it is expanding to a lower pressure through your regulator and as a result you are breathing very dry air....
My question would be, is the air being tested by your instrumentation at 3000 psi when being tested?.... Here is another recent thread about moisture content in compressed air.... https://www.gatewaytoairguns.org/GTA/index.php?topic=139845.0 (https://www.gatewaytoairguns.org/GTA/index.php?topic=139845.0)
At the bottom of the original post is a link to a .pdf file that shows the ACTUAL moisture content (not the relative humidity) of air at various pressures, and the standard for Class 1 breathing air.... If I interpret that information correctly, at 4500 psi there is only 0.002 grams water per cubic meter for Class 1 air.... yet the air is not saturated until it has 0.06 grams / CM.... By comparison, at 1 atmosphere, air is not saturated at 68*F until it contains 17.5 grams of water.... If you have the ability to measure the Dew Point, according to that table, anything lower than -48*F at ambient pressure would not be saturated at 4500 psi.... If you can get to -50*F Dew Point, you should never see any liquid water in your tank, if I am reading that table correctly....
Bob
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Bob,
Thank you for participating in this thread. I have been trying to find a good rule of thumb for air drying for over a year.
I admit I am also not an expert and when we start talking about 4500 psi presures and what happens to humidity the confusion sets in for me.
I just found this calculator: http://www.michell.com/us/calculator/ (http://www.michell.com/us/calculator/) but I don't know what figures to enter for pressure.
Even then, I still have questions. Let's take the example at the end of your post right above mine. So a -50°F dew point at 4500 psi there shouldn't be any liquid water. But how much water vapor or relative humidity is there at 4500 psi? Is it zero also? Does it even matter at this point? This is where my brain gets stuck.
I am not at all contesting what you are saying. I'm just looking for an explanation that my brain will understand. :)
I'm all about discussing, brainstorming and learning. I just get confused with what dew points and relative humidity mean at 4500 psi. I'm sure I am not the only one.
Also, how many cubic feet are actually in an 88 ft³ 4500 psi carbon fiber cylinder? Would it be (4500/14.7)*88=26938.78 ft³?
I should have taken more physics. But I guess it's never too late to crack open a physics book, is it? ;D
Thank you,
Taso
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I think I found some answers, with the help of some research and this calculator.... http://www.dew-point.com/dew-point_calculator.asp (http://www.dew-point.com/dew-point_calculator.asp)
The required humidity standard for maximum Dew Point (atmospheric) for Breathing Air depends on the Class....
Class 1 = -70*C (-94*F).... This is 2.6 PPMV, or 0.002 g/m3.... Dew Point at 4,500 psi = -22.6*C (-9*F)
Class L (SCBA) = -53.8*C (-65*F).... This is 24 PPMV, or 0.02 g/m3.... Dew Point at 4,500 psi = 2.8*C (37*F)
Class D = -45.5*C (-50*F).... This is 67 PPMV, or 0.05 g/m3.... Dew Point at 4,500 psi = 18.2*C (65*F)
Class 2 (SCUBA) = -40*C (-40*F).... This is 127 PPMV, or 0.1 g/m3.... Dew Point at 4,500 psi = 28.8*C (85*F).... but at 3,000 psi typical for SCUBA, DP = 22*C (72*F)
Basically, the drier the air, the lower the temperature you can store your tank at without getting liquid water forming.... Therefore, you can look at the above choices and decide what is the lowest temperature you might store your SCBA tank at for prolonged periods of time, and you can know how dry your air must be.... The Class L SCBA standard should be plenty good enough unless you store your tank outside, in freezing conditions.... If you have it inside a heated building, even in a basement, then Class D air, should be just fine.... That has an atmospheric Dew Point of -50*F, or 67 PPMV of water.... I am going to use that for my goal.... Since SCUBA tanks are usually only filled to 3,000 psi, they can get away with Class 2 air....
Something else to consider.... If you fill your PCP to 3,000 psi from a 4,500 psi tank containing Class D air (67 PPMV), the Dew Point at 3,000 drops to just 12*C (53*F).... Yes, the air gets "drier" as it expands when filling your gun, so you can never get liquid water in your PCP if you fill it from a tank, unless you invert the tank and spray liquid water into it.... If you fill only to 2,000 psi, the Dew Point at that pressure is even lower, at 6*C (43*F).... I knew, intuitively, that you couldn't get water in a PCP when filling from a tank at a higher pressure.... but now I have the proof.... The only time you could have water condense out inside a PCP would be in freezing conditions.... and then it would evaporate again as soon as it warms up.... Actually, as the air pressure in your SCBA tank drops as you fill your PCPs, it will absorb more water, should there be a trace of it in the tank.... By the time you get the SCBA tank down to 3,000 psi, the relative humidity will be down to 60%, because the air can hold more water as the pressure drops.... This means that your tank (and your gun) will kind of "self-dry" as the pressure drops....
Taso, an 88 CF SCBA tank holds 88 CF of air.... The tank would only hold 550 CI (9 litres) of water, so you are compressing that 88 CF of air into only (550/1728) = 0.32 CF of space.... As I understand it, you don't really care what the relative humidity of the air is in your tank (or gun), as long as it is less than 100%, which means there will be no liquid water condensed out to cause corrosion.... Since the air can hold more water as the pressure drops, the worst condition will be right after you fill it, when it cools to ambient (storage) temperature.... If there is no liquid water in it then, it will never have any, unless you cool it down further.... and then the water will evaporate again as soon as it warms back up....
Hand pumping directly into a PCP is a different story completely, of course....
Bob
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The air sample was coming out of each device at 3000 psi. The reason for this is I don’t have a way to regulate pressure coming out of the tank. But the pressure then hits the instruments regulator and then goes into a sample chamber if I remember correctly the gas is only samples at like 30 psi. However both samples were taken comparative. So in my mind the compressor air is wet. For sure its considerable wetter than the air I have been buying. Is it to wet? I am not sure, however I will be adding a filter before I put it in my bottle. I just wish I could find one locally instead of waiting for shipping. I have to keep in mind a couple thousand in guns, 500 dollar bottle, 1800 dollar compressor. I would be stupid to take a chance on a couple hundred dollar filter. Please remember I am guessing because I don't have a written standard what dry air is for a PCP. everything I have ever tested professionally I have a standard.
thanks, Jim
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Jim, now that I have done the research, I have a better understanding of what the ATMOSPHERIC Dew Point, and the PPMV you are quoting actually mean.... and as you will see in my post above, they directly relate to the point at which water will condense out in your tank, depending on temperature and pressure.... 24 PPMV air is certainly VERY dry (Dew Point -65*F), you could store a 4,500 psi tank at 37*F and still not get water condensing out.... My personal goal has just become an atmospheric Dew Point of -50*F, or 67 PPMV, which is Class D air.... If I can get there, I am confident that I will never have liquid water in my SCBA tank....
Bob
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Jim, now that I have done the research, I have a better understanding of what the ATMOSPHERIC Dew Point, and the PPMV you are quoting actually mean.... and as you will see in my post above, they directly relate to the point at which water will condense out in your tank, depending on temperature and pressure.... 24 PPMV air is certainly VERY dry (Dew Point -65*F), you could store a 4,500 psi tank at 37*F and still not get water condensing out.... My personal goal has just become an atmospheric Dew Point of -50*F, or 67 PPMV, which is Class D air.... If I can get there, I am confident that I will never have liquid water in my SCBA tank....
Bob
67 PPMV sounds reasonable. I am curious how much a inline high pressure filter will decrease my air. As an above post mentioned breathable air is not really dry, even in the desert. Thanks for your participation in the conversation, and everyone else also. I am in new territory playing with these over priced BB guns.
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Lots of good stuff going on this thread. Nice to see people are getting their heads around the uselessness of thinking in terms of relative humidity - given that we are working at different pressures nothing is "relative" - and we are working in absolute humidty values of grams of water per standard cubic meter, or PPM . . .
First off to Bob - I am confident that you will be getting to class D air (or better) with the set up you are moving too (the large desiccant filter using silica gel), as I have verified that my set up with the same basic filter has done just that. I put 10 cubic meters of air through my tank using that set up with a Shoebox compressor and found zero trace of any water when I vented the tank and inspected it. You also have a solid understanding of moisture in air now.
To Jim (and pretty much everyone else)- you have to get a dryer; we all do for long term safety reasons with our tanks. At a minimum, we need to to be able to know that our tanks will live a long full life without early corrosion (especially considering many with SCBA tanks and their own compressors will exceed the last hydro / rated life of the tanks). The bottom line is that without a dryer the air leaving the compressor and entering a tank is going to be saturated with water vapor at whatever temperature and pressure the air is leaving the compressor. Which is guaranteed to mean that some water will condense out of the air that has been added to the tank - and as we repeat that it will build up over time.
The challenge you face with an all in one compressor like the Omega is that the only practical way to dry the air is with a desiccant filter after compression, like Joe B's Alpha or the gold filter from China. There is so much water vapor in ambient air that you will need a lot of desiccant to dry it before compression. Even the air in your freezer has about 1.5 grams of water vapor per cubic meter in it - I suppose that if you drew the air out of your freezer and passed it through a desiccant filter like Bob and I are doing you would be able to get where you want to be without saturating the desiccant very quickly.
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Something you may want to consider.... In the thread I mentioned in my first post, in the OP's attached .pdf file, he states that Silica Gel Beads can dry the air to 0.07 g/m3.... Using the online calculator I found, that works out to 92 PPMV, or an atmospheric Dew Point of -42.8*C (-45*F).... At 3,000 psi, the Dew Point would be 16.8*C (43*F), so if you are only filling SCUBA tanks, that would be good enough.... At 4,500 psi, the Dew Point would be 23.4*C (74*F), so you might get a trace of water in the tank right after filling (depending on your ambient temperature), but that water would evaporate as you used air from the tank and the pressure dropped....
I use Silica Gel Beads, and in the not too distant future (ie when the tank is empty) I will be pulling the valve from my Great White to check for water.... AlanMcD, the author of the thread I linked to, already did that, and despite having calculated that he should have had some water in his tank, found none, nor any traces of corrosion.... He uses Silica Beads between his Shop Compressor and Shoebox, just like I do, but he has a much larger dessicant filter than the two small inline filters I have been running (I change when the 2nd one turns mostly pink, yeah I'm lazy).... but I have a much larger one coming.... Using the Silica Gel Beads between the Shop Compressor and the Shoebox means that you have much less water to remove, because most of it will have condensed out in the Shop Compressor tank, to be drained regularly.... In fact, once the shop air, at 125 psi like I use at the input to my Shoebox, has dropped back to room temperature (I have a 2 gal. holding tank before my dessicant filters), it has already lost about 93% of the water it held, if you started at a humidity of 100%.... At 68*F, the 125 psi air I feed into my Silica Gel filters can't have more than 1.8 g/m3 of water in it.... It only takes about 0.8 m3 to top up my Great White from 3000 psi back to 4500.... so I only need to remove about 1.4 grams of water over a 3 hour period, to get where I need to be....
Alan, you just gave me an idea.... How about if I put my 2 gal. 125 psi holding tank in a bar fridge and then feed the air from there through my dessicant filter.... make any sense?.... any gains possible, or can the Silica Gel only get down to 0.07 g/m3 no matter what the temperature and starting humidity?....
Bob
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Bob,
That big filter full of silica gel will get you there regardless of the start point - the only question is how long it will take before you have to recharge it . . . .
I too have thought of passing it though my freezer, at least in the summer time. I run my compressor in the garage, so I probably average about 35F for my compressor dewpoint in the winter, but a higher temp in the summer (although the air cools in my manifold in the basement, so about 68F). In the end it averages out to a reasonable level and I just verified that by drying out my desiccant last week, along with rebuilding the cylinders in my Shoebox. My log and hour meter show that I ran it for 145 hours, and my calculations show I average about 6.6 cubic feet per hour through my Max, so that works out to about 27 cubic meters or air through my filter (plus maybe another cubic meter or two vented through the compressor when it was not running as the filters bleed down, but I am not including that as I don't know how much that is). I weighed the desiccant before and after, and it was 50 grams of water that were removed when I dried the beads, so that works out to 1.9 grams of water removed per cubic meter of air. I don't know how dry the beads were when I started, so I can't say for sure all of it came from the air I flowed through the Shoebox (that seems a touch high for what I would have expected), but it is in the ballpark . . . .
I will point out that the beads were still blue when I dried them, but definitely a light blue and not the deep blue they resulted in when I dried them. Also, that 50 grams works out to 6% of the weight of the beads, so well within the saturation level so there was no rush to do it then - I was just curious what I would find so I did it to see.
Given that you are up in Canada, you could also do the same - just run the compressor outside and save the hassle of passing the the air though the fridge. I love having the compressor in the garage and not in my shop. It keeps the noise outside too.
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What "filter container" do you use for your high side?
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Jim,
Neither Bob or I filter on the high side - we filter between the shop compressor and our Shoebox compressors. If you mean the high side, I am not sure who you are asking.
On the input side, I run this as my desiccant filter, and Bob has ordered one very similar to it: https://www.zoro.com/wilkerson-dryer-desiccant-x03-02-000/i/G0780071/ (https://www.zoro.com/wilkerson-dryer-desiccant-x03-02-000/i/G0780071/)
I believe that I exceed the -45F dewpoint with this unit because the flow rate when used feeding the Shoebox is less than 1% of the flow rate the filter is designed to support at a -45F dewpoint. So the dwell time for the air is off the charts, and I get air that is dryer than rated. It would be interesting to test the air in my tank as you did, but I have no way to do that. My only test was to open it up after much air had been passed through it, and I verified that that it was bone dry and that there was no signs of there ever having been water in it.
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Given you have the instrumentation, it would be nice to see pre and post filter numbers, once you get one. Be it the DIY gold filter or an aftermarket one.
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My filter is a lot smaller than Alan's.... but way bigger than the two small inline filters I have now.... The flow rate is, like on Alan's, MANY times greater than what goes through a ShoeBox.... I am thinking I should install valves on both sides to isolate it from the air when not in use to prolong the life of the beads....
Bob
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Bob,
I just use male/female compressor hose fittings. When not in use, just wrap the input to the output. I do that for the longer coiled hose with inlines, and the larger filters that are about 2' away from 1st stage compressor. Just a thought.
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My filter is a lot smaller than Alan's.... but way bigger than the two small inline filters I have now.... The flow rate is, like on Alan's, MANY times greater than what goes through a ShoeBox.... I am thinking I should install valves on both sides to isolate it from the air when not in use to prolong the life of the beads....
Bob
Or you can use a dead head. I have a couple from hpa pumps.
Taso
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Output back to input with a rubber hose might work, I will keep that in mind when I do the installation, instead of using hard pipe.... If not, I had already thought of a deadhead on the input to my holding tank, where I usually hook up the compressor hose.... If I turn the crank on the shoebox vertical it shuts off the flow there.... just have to remember to do it after use.... Dessicant filter is supposed to arrive tomorrow....
Bob
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Bob,
I used a 1/4 turn ball valve on the input, and I rotate the Shoebox pistons to full compression on the output side for a shut off. It is easy to remember to do that - I always vent the high pressure air out the hose with the Shoebox vent (never the tank fill line vent), and then rotate the crank to shut off the air flow that I continue to hear venting. Then I close the vent and disconnect the tank hose.
Here is a picture of mine. Since I have the Shoebox Max I regulate the pressure into the unit at 100 psi, and I also have a 0.1 micron filter in line after the desiccant filter to trap and silica dust. You will notice that I also have a quick disconnect on a flex line into the Shoebox. I did this so that I could easily use my dryer for other purposes besides the Shoebox, like for spray painting or anything, but I am yet to do so. It stays with the unit on it's stand all the time.
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Taso-
The calculator that you linked in an early post, is for atmospheric pressure only. High pressure air is MUCH more corrosive, both to steel, and aluminum.
"Another point I'd like to add is that breathing air is required to have some humidity as to not dry out diver's air passages. So I don't agree that the breathing standard humidity level is correct for air rifles or air cylinders.
SCUBA divers don't need moisture in the air. Breathing air is specified to be very dry, whether it's SCUBA, or SCBA.
https://airanalysis.com/Moisture_In_SCUBA___SCBA.html
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Doug,
Thank you for the clarification on the humidity level on breathing air. I misunderstood and thought there needed to be more humidity in the air for not drying out divers.
You are correct on the first dew point calculator, that is only for atmosheric pressure. But I mention it's the first and only one that has included a corrosion level. I later link to another calculator that does take pressure into account but I'm not sure how to use it.
I just found this calculator: http://www.michell.com/us/calculator/ (http://www.michell.com/us/calculator/) but I don't know what figures to enter for pressure.
I agree that high pressure air is more corrosive than atmospheric. What level of moisture does that final hpa need to be under to not promote corrosion? I know that it has been discussed to remove all liquid water from 4500 psi. So I posed the question do we still need to be concerned? I think we do. The air may still be at 100% relative humidity and may still cause corrosion. Or not. I don't know for sure.
Thank you,
Taso
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So I was drinking my coffee and thinking lol. So is it this last bit of water vapor at 4500 psi that the molecular sieve is supposed to target?
I do geek out with all of this and is possible I go a little overboard sometimes. So I was hoping we could come to an effective frugal setup that will do what is required.
I had included ideas from reading in my Shoebox drying thread but as I learned more about drying air the plan of attack has changed. ;D
Thanks,
Taso
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I got my new filter yesterday, and installed it today, with a ball valve on the inlet like Alan did, so by closing that and putting the ShoeBox on full compression the dessicant is isolated from the air in my shop.... The filter is smaller than I thought, I guess the dimensions (3' x 3" x 8") were for the box, the filter is only about 6" tall.... The bowl is only about 2" x 4", but still holds probably 10 times as many beads as the small inline filters, and it came with two (sealed) bags of dessicant (a fill and a spare).... Anyways, I'm sure it will last way more than 1 fill, which would turn the first inline filter I had pink and the second one about halfway, which didn't give me much confidence.... We'll see how long the new setup lasts between reconditioning the beads....
Bob
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I used my new dessicant filter for the first time today.... a 4 hour top-up of my 88CF SCBA tank.... The silica beads are all still bright blue, with no hint of pink anywhere.... I am DELIGHTED !!!
Bob
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I used my new dessicant filter for the first time today.... a 4 hour top-up of my 88CF SCBA tank.... The silica beads are all still bright blue, with no hint of pink anywhere.... I am DELIGHTED !!!
Bob
Cool I have mine set up but have not filled my tanks yet, still need to shoot some more to get them down to where I need to fill them.
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I got my new filter yesterday, and installed it today
Bob
Don't we get to see a picture? (http://www.cafehusky.com/smilies/excuseme.gif)
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Here you go....
(http://i378.photobucket.com/albums/oo221/rsterne/Parts%20for%20Sale/New%20Filter%20on%20ShoeBox_zpspfdt0nhx.jpg) (http://s378.photobucket.com/user/rsterne/media/Parts%20for%20Sale/New%20Filter%20on%20ShoeBox_zpspfdt0nhx.jpg.html)
The new filter has been used for two top-ups from <3000 to 4500 of an 88 CF SCBA tank.... and as you can see the beads are still bright blue.... The ShoeBox is a Freedom 8, mounted on the white plywood base, along with a 2 gallon air tank from a dead compressor.... The 125 psi regulated air from my 6 gallon Shop pancake comes in through a 25' coil hose (red) to allow it to cool, and then through an oil/water trap (which never has anything collect in it) into the blue 2 gallon tank.... From there it goes through an isolator valve (shown closed) to the new Silica Gel dehydrator, and from there via a flex hose to the inlet of the ShoeBox.... The vertical piece of 2x2 is screwed to the corner of the white plywood and supports the output end of the filter to prevent vibration and/or damage from bumping it.... To isolate the beads between uses, I shut off the valve on the inlet side of the dehydrator, and turn the output crank of the ShoeBox to full compression (as shown).... Alternately, I can remove the flex hose from the ShoeBox inlet and wrap it around to the QD fitting on the oil trap.... I think isolating the beads from the air in my shop greatly increases the time that will be needed between reconditioning the Silica Gel.... I will do that by baking for 30 min. in a toaster over an 250*F.... I am keeping track of how many hours I can run the ShoeBox before having to do that.... With my previous setup (2 small inline dryers) I had to bake the beads before every use....
Bob
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Bob
Thank you for the photo's/info along with the others that posted photo's on their dryer/filter set up's,
I can now see what everything is and get an Idea on how to follow in your/everyones foot steps etc.
Would a larger Wilkerson filter be or provide better protection?
There is 2 different sizes.
I have found some Wilkerson's that are 12-13" tall, kinda expensive thou.
Thank you
Don
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It doesn't matter how big the filter is, provided you can get a few fills before it starts to turn pink, IMO.... The filter I now have has many times the CFM capacity that the ShoeBox uses (my Freedom 8 is about 8-9 CF/hr., so about 0.15 CFM), so a filter with a 15 CFM flow rate is 100 times what you need.... The bigger the filter, the longer the air takes to move through it, but past a given time, I really doubt that makes it any drier.... The size filter I have probably takes about a minute for the air to move through it.... I have no idea (yet) how many fills I can get before I see any pink....
I previously had two small inline filters that held only about a tablespoon of beads each.... and the first one would be pink, and part of the second one (how much depended on the humidity at the time) during a refill of my 88 CF SCBA tank from 2800-4500 psi (which takes about 4 hrs.).... I had to bake the beads before each time I used the ShoeBox.... I have two of those fills on the new filter, and no sign of any beads changing colour yet....
Bob
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Thx Bob for the pic. Looking Good !
You say that after 4 hrs of running the beads never showed any signs of color change...is that a good thing? At what point do you think they will start turning. After 4 hrs a slight color change would be a good thing. No ?? Does that filter flow bottom up?
I see all filtering is done on the low side...Do you have filtering down stream of the ShoeBox?
Geez..Sorry for all the question...Trying to piece things together myself.
(https://i.imgur.com/fVQGyFk.jpg?1)
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Actually about 8 hours, and while the beads may be a slightly lighter blue, there is definitely no pink.... AlanMcD has a much larger filter (1.75 lbs. of beads) and after 145 hrs. his beads were a lighter blue than after he baked them.... I have no filtering downstream of the ShoeBox, the volume of the filter would take a lot of air to fill at 4500 psi, plus the filter has to be built for that, of course.... I believe the flow is bottom up, I'll check when I eventually pull it apart.... The flow direction on the inlet and outlet is marked on the housing with triangles cast right in....
Alan has a link to his filter on the previous page, and if I read it correctly, it can remove the water from 4,400 CF of air.... about 50 complete 88CF fills or 150 top-ups.... Mine is much smaller, but huge compared to the two inlines I had before....
Bob