MCH6 Filter lifetime
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Are the aluminum?
Craig
No everything steel. I didn't know that the compressor filters are all Aluminium, but makes sense with the moisture.....
Jimmer
Contributor
Other than aluminum not aging as well as steel, there is also the fact that compressed air is more dangerous than hydraulic fluid. If a hydraulic cylinder ruptures, you get oil everywhere, since the fluid is essentially uncompressed, if a pneumatic cylinders ruptures, you get a big a$$ explosion because the air is compressed into a tiny space, and it wants to decompress back to ambeint.
Of course compressed gases are more dangerous, but there are bad hydraulic accidents. I recalled a failed valve and from a 300-500 mm (can't recall) cylinder the screws fly away, real big ones and thru the wall.
Leaks can cut. I know one company where one guy got shot thru the head with the oil.
But of course such things are very rare, but I also never heard from exploding compressors. (But some times from exploding tanks due to rust). I am often surprised how little happens.
Jimmer
Contributor
High pressure anything can be a problem. I can see how a small hole in a hydraulic cylinder would turn it into a waterjet machine! I don't have any details but I know of a shop locally to me a few years ago that blew the final stage head off their compressor.
oxyhacker
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The hazards from hydraulic equipment bursting are not comparable with the hazards from high pressure gas, since oil is incompressible so it does not store up energy the way a gas at a similar pressure would. So a hydraulic cylinder at 3000 psi will not have anywere near the explosive potential of a similarly sized filter stack or cylinder at the same pressure, and can be treated quite casually.
Now when you tell I recall to read a final stage of a compressor fly away on a boat and went thru the walls without any problems.
In my country you have every few years an idiot farmer who is welding a wheel of his tractor with the air in the tire. even that low pressure kills (or almost kills) you.
H90,
No PMV ? Holy Cow !!!
25 grams is too little and surely never 10 hours life at 30C ambient.
Here is how Bauer calculate the filter life and this is assumed the PMV is set at 2,000 psi or 136 BAR:
Volume of air which can be processed:
Va [m3] = 0,2 x mMS [g] / (X [g/m3] / p [bar]) = 0,2 x p [bar] x mMS [g] / X [g/m3]
So for your Coltri MCH6 with 25 grams, its like :
{ 0.2 x 207BAR x 25 gram } / 65.62 = 15.77 cubic meter or 15,772 liters
If your compressor is an 80L per minute model, so its 15,7770 / 80 = 197 minutes
0.2 its the water holding capacity of molecular sieve
207 BAR is tank pressure of 3,000 psi
25 grams is what you said your filter capacity for the molecular sieve
65.62 is the water content in grams for 1,000 liter of air at 100% humidty at 45 Celcius. It is always a 100% humidity when the compressor compressed the air. Always add 15C above ambient as final temperature at final water separator or filter housing if the filter housing is a combo of water separator and filter housing.
Final Temp at filter Housing >> Water Content in grams per 1000 liters of air
40.0C >>>>>>>>>>>>>>>>> 51.21
41.0C >>>>>>>>>>>>>>>>> 53.83
42.0C >>>>>>>>>>>>>>>>> 56.57
43.0C >>>>>>>>>>>>>>>>> 59.43
44.0C >>>>>>>>>>>>>>>>> 62.41
45.0C >>>>>>>>>>>>>>>>> 65.52
46.0C >>>>>>>>>>>>>>>>> 68.75
Molecular sieve only adsorb water 20% of its own weight. Some say 23% but 20% is better because the air need to be very dry to pass proper air standard. So your 25 grams of MS can only adsorb 5 grams of water or 100 drops. This is why water separators and PMV is soooooooooooo important.
PMV is important because it allows the air to be kept at 136BAR ( assumed 136 BAR setting ) constant in the filter housing before releasing it to the tank. Many Americans called PMV as Back Pressure Valve. LF call it Priority Valve, all the same thing.
Not only PMV allows the media which is the dryer aka molecular sieve and the poison adsorber which is the activated carbon to have more contact time with air aka dwell time, it also allows simple physics to work. Increase in pressure, the air hold more water. So by allowing 136 BAR pressure built up in small filter housing, the water separator facility at the filter housing ( assumed it is a combo filter+water separator ) can remove more water from the air due to the higher pressure.
Without a PMV, to reach 136BAR for a 80CF tank at 80 liters per minute, it will take approx 17.8 minutes. In these 17.8 minutes, your filter media would be very wet fast. If a filter housing is say 1 liter volume, to reach 136 BAR at 80 liters per minute it only need like 102 seconds and only 136 liters of air in it. So, one can remove water from air efficiently since the filter housing is always at high pressure. I don't thing anyone knows how efficient the mechanical water separator is to the exact percentage but some said its like 98-99% efficieny of water removal capability. The way Bauer calculate its filter life, it seems they use approx 99.4% as water separator ( two water separators ) water removal efficiency
Think about it, assuming water separator can remove 99% of water. At 45C final air temperature, one empty 80CF tank will need easy 2,000 liters of air. At 45C, water content is 65.65 x 2 = 131 grams or cc. 99% removed by water separators, you still have 1.31 grams of water. That 1.31 grams of water per tank will soak your 25 grams MS in no time.
Do you know what Bauer P21 filter of 68 grams MS reccomends at 45C final temperature, its only 4.xx hours at 200 liter perminute at 200 BAR or 20 tanks of 80CF empty.
Now, depending on your filler whip/hose design, without a PMV and without some sort of shut down valve at the filler Yoke, when you change tanks and have to remove the air from the hose, you may end up removing air from the entire filter housing. I am not familiar with Coltri. In a Bauer filer whip, it has a special valve which remove only the air at the yoke and not the hose. Less than 50cc of air at 1 BAR or at the most 10 liters of air at 200 BAR. Also Bauer always has a PMV at the output of all their filter housing. I am not suprised Craig was stunned that in this day and age, a compressor manufacturer can be so cheapo by not providing a PMV which is only like US$75 or so for American type PMV on a near US$3,000 compressor
Again about this PMV thingy.
If a PMV is set properly and installed, the life of the filter housing will be longer, because it will be 140-207-140 BAR pressure cycle. If there is no PMV and a user get to cycle the filter housing 0-207-0 BAR for every tank change, the filter housing which is a pressure vessel will be much shorter lived. If I see Bauer pressure vessel life, typically it can be reduced by 60%+ if 0-207-0 BAR is the pressure cycle, compared to 140-207-140 BAR pressure cycle.
Good luck maintaining your baby Coltri.
IYA
No PMV ? Holy Cow !!!
25 grams is too little and surely never 10 hours life at 30C ambient.
Here is how Bauer calculate the filter life and this is assumed the PMV is set at 2,000 psi or 136 BAR:
Volume of air which can be processed:
Va [m3] = 0,2 x mMS [g] / (X [g/m3] / p [bar]) = 0,2 x p [bar] x mMS [g] / X [g/m3]
So for your Coltri MCH6 with 25 grams, its like :
{ 0.2 x 207BAR x 25 gram } / 65.62 = 15.77 cubic meter or 15,772 liters
If your compressor is an 80L per minute model, so its 15,7770 / 80 = 197 minutes
0.2 its the water holding capacity of molecular sieve
207 BAR is tank pressure of 3,000 psi
25 grams is what you said your filter capacity for the molecular sieve
65.62 is the water content in grams for 1,000 liter of air at 100% humidty at 45 Celcius. It is always a 100% humidity when the compressor compressed the air. Always add 15C above ambient as final temperature at final water separator or filter housing if the filter housing is a combo of water separator and filter housing.
Final Temp at filter Housing >> Water Content in grams per 1000 liters of air
40.0C >>>>>>>>>>>>>>>>> 51.21
41.0C >>>>>>>>>>>>>>>>> 53.83
42.0C >>>>>>>>>>>>>>>>> 56.57
43.0C >>>>>>>>>>>>>>>>> 59.43
44.0C >>>>>>>>>>>>>>>>> 62.41
45.0C >>>>>>>>>>>>>>>>> 65.52
46.0C >>>>>>>>>>>>>>>>> 68.75
Molecular sieve only adsorb water 20% of its own weight. Some say 23% but 20% is better because the air need to be very dry to pass proper air standard. So your 25 grams of MS can only adsorb 5 grams of water or 100 drops. This is why water separators and PMV is soooooooooooo important.
PMV is important because it allows the air to be kept at 136BAR ( assumed 136 BAR setting ) constant in the filter housing before releasing it to the tank. Many Americans called PMV as Back Pressure Valve. LF call it Priority Valve, all the same thing.
Not only PMV allows the media which is the dryer aka molecular sieve and the poison adsorber which is the activated carbon to have more contact time with air aka dwell time, it also allows simple physics to work. Increase in pressure, the air hold more water. So by allowing 136 BAR pressure built up in small filter housing, the water separator facility at the filter housing ( assumed it is a combo filter+water separator ) can remove more water from the air due to the higher pressure.
Without a PMV, to reach 136BAR for a 80CF tank at 80 liters per minute, it will take approx 17.8 minutes. In these 17.8 minutes, your filter media would be very wet fast. If a filter housing is say 1 liter volume, to reach 136 BAR at 80 liters per minute it only need like 102 seconds and only 136 liters of air in it. So, one can remove water from air efficiently since the filter housing is always at high pressure. I don't thing anyone knows how efficient the mechanical water separator is to the exact percentage but some said its like 98-99% efficieny of water removal capability. The way Bauer calculate its filter life, it seems they use approx 99.4% as water separator ( two water separators ) water removal efficiency
Think about it, assuming water separator can remove 99% of water. At 45C final air temperature, one empty 80CF tank will need easy 2,000 liters of air. At 45C, water content is 65.65 x 2 = 131 grams or cc. 99% removed by water separators, you still have 1.31 grams of water. That 1.31 grams of water per tank will soak your 25 grams MS in no time.
Do you know what Bauer P21 filter of 68 grams MS reccomends at 45C final temperature, its only 4.xx hours at 200 liter perminute at 200 BAR or 20 tanks of 80CF empty.
Now, depending on your filler whip/hose design, without a PMV and without some sort of shut down valve at the filler Yoke, when you change tanks and have to remove the air from the hose, you may end up removing air from the entire filter housing. I am not familiar with Coltri. In a Bauer filer whip, it has a special valve which remove only the air at the yoke and not the hose. Less than 50cc of air at 1 BAR or at the most 10 liters of air at 200 BAR. Also Bauer always has a PMV at the output of all their filter housing. I am not suprised Craig was stunned that in this day and age, a compressor manufacturer can be so cheapo by not providing a PMV which is only like US$75 or so for American type PMV on a near US$3,000 compressor
Again about this PMV thingy.
If a PMV is set properly and installed, the life of the filter housing will be longer, because it will be 140-207-140 BAR pressure cycle. If there is no PMV and a user get to cycle the filter housing 0-207-0 BAR for every tank change, the filter housing which is a pressure vessel will be much shorter lived. If I see Bauer pressure vessel life, typically it can be reduced by 60%+ if 0-207-0 BAR is the pressure cycle, compared to 140-207-140 BAR pressure cycle.
Good luck maintaining your baby Coltri.
IYA
Jimmer
Contributor
The pressure may be low, but the volume of the tire means there is a lot of potential energy stored in there. It's the same reason they try to keep the filter towers for scuba compressors as small a diameter as possible, to limit the potential energy stored inside. I used to work as a design engineer designing water and oil filtration vessels, some of which were over 2 metres in diameter. They may have only been 150 psi, but the energy stored in those vessels was incredible.
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