nitrox blending

[abnfrog]

here's something new , I have always thought /taught you can blend up to 40 % threw your compressor , but in a conversation with the repair guru at jordair in bc (my compressors there for rebuild) he tells me NO WAY they have to be a nitrox block ! and that's about 2x as much money ....so what's the deal he says he's seen lots of blown up compressors because of doing it ............. anybody else seen it ?

 

[BoltSnap]

here's something new , I have always thought /taught you can blend up to 40 % threw your compressor , but in a conversation with the repair guru at jordair in bc (my compressors there for rebuild) he tells me NO WAY they have to be a nitrox block ! and that's about 2x as much money ....so what's the deal he says he's seen lots of blown up compressors because of doing it ............. anybody else seen it ?

If you do "continuous blending" using the "Nitrox stick," the blending is taking place before the nitrox enters the compressor air inlet. Is he claiming that this will be a problem for their compressor brand?

 

[abnfrog]

that exactly what hes saying you most defiantly shouldn't put 40 % into a non nitrox block .....by the way jordair is also Bauer

 

[BRT]

that exactly what hes saying you most defiantly shouldn't put 40 % into a non nitrox block .....by the way jordair is also Bauer

What is he saying the difference is between nitrox and non nitrox blocks?

 

[RayfromTX]

@tbone1004 what is your opinion?

 

[tbone1004]

@tbone1004 what is your opinion?

CYOA policy and/or misinformation.

RIX is adamant about air only in their compressors, but I know guys that regularly pump EAN32 and EAN36 through them with no issues. I also know people that pump EAN50 through them. As long as the air is properly mixed prior to the intake port, it shouldn't be an issue.

I believe firmly in standard gases, and the only thing that should be going through a compressor IMHO is air, and EAN32 or EAN36. Anything else should be PP filled then topped off with one of those three gases. You can't O2 clean an oil cooled compressor, so the Rix is the only one that "could" be O2 cleaned *a company in England sells kits to convert them to O2 use for boosters*. Any oil cooled compressor is going to get oil in the various stages, and that could be really ugly with the rich mixes.

With the oil compressors you have the added risk of oil in the blocks, but thousands of cubic feet of EAN32 get pumped in cave country every day and most all of them are on Bauer compressors. I am not aware of any "nitrox kits" for Bauers. Not to say they don't exist, but if you're staying within recreational nitrox limits, it should be a non-issue.

In terms of misinformation, this is also similar to the genius's who say that second stages on your reg set need to be O2 cleaned, or those that say your first stages need to be O2 cleaned for Nitrox use. Only thing that should be different for nitrox use is if you are PP blending and then it's only the valve/cylinder. Nothing needs to be done to your first stages for nitrox us up to 40%, and nothing ever needs to be done to your second stages. You can choose to O2 clean your second stages in terms of the general cleaning process, and then choose to use the same O2 clean lubricants because you don't want to risk contaminating your first stages on the bench, or are too lazy to set up a second station for it, but no need to use the viton parts kits on them.

 

[rddvet]

It's possible he may be recommending at 4 stage compressor over a 3 stage compressor. My Bauer tech told me before buying that if I planned to pump nitrox that I should get a 4 stage block because it generates less heat not even sure if this is true. But I have heard it referenced by others as well, and one person referred to a 4 stage compressor as a "nitrox block"

 

[NAM001]

Anything with higher O2 content will degrade the compressor performance. OK a lot of words that say nothing. Much like warrentees. If you can get 5000 hours between valve changing pumping air, and with nitrox you get 4500 hours then is there a danger or is the compressor not able to live up to the specs as rated for air only? Yes additional O2 will cause More not Original carboning. Yes there is more carbon build up. is there some predetination in the compressor to a higher rate than with air. YES. does that mate it dangerous with a proper filtered system. Probably not. Other factors are specs like can pump with in humidity of 15-90%. So what. the catch you there is that the air's humidity is used for cooling so you run it in 15% humidity and you are pumping air with O2 that is IE <.1% humidity and the over level is now say 12% entering the compressor. will that be good for the compressor. NO Is it the O2 that is causing the problem of the humidity being reduced to less than the recommended minimum 15% that is the problem? Even RIX does not support pumping enriched air with its oil free compressors that are not specialty designed O2 compressors. But if its 70% outside and you are blelnding the overall humidity is within spec, Then what ???. face it, you are only adding about 10% of the pumping volumn to get 32 %. Yes that's doubling the O2 content. that's a far cry from pumping 80% deco. Next is predetination causing CO in the output. You are not causing CO in the output you are increasing the CO in the output. As long as there is oil in the compressor and on the cylendar walls the output will have CO. That's what a filter is for,,, to convert the Co to CO2 that then remove it.

There is no wining the discussion when you look at the numbers cause you don't know what the numbers are saying.

When it comes to making nitrox yo can't PP blend cause you will blow up form the right angles in the tank valve. You cant Continous blend cause the system is not rated for pumping pure O2.
And don't forget that when handling more than 23.5% O2 everything has to be O2 cleaned. What company will make a compressor and then tell you the maintenance costs are through the roof.

Run synthetic oil and pump with reasonable humidity in the area you should be OK. Is this 100% good advice, NO. However how many of you are driving a car that has not had the timing belt replaced at 60K and you now have 150 K and still have not blown up the engine. Its a balance of risks and cost management. May I add another thought. The home pumper is not pumping thousands of CUFT a day like a large shop will. If I have a choice,,,, and I do,,,,, I PP blend. If you are knowledgeable to properly care for a compressor you should be mentally equipped to continuous flow blend at low percentages. Remember NASA's reaserch says O2 below 60% acts like air. so 40% should be, safety wise, well with in margin let alone 32%.

 

[NAM001]

It's possible he may be recommending at 4 stage compressor over a 3 stage compressor. My Bauer tech told me before buying that if I planned to pump nitrox that I should get a 4 stage block because it generates less heat not even sure if this is true. But I have heard it referenced by others as well, and one person referred to a 4 stage compressor as a "nitrox block"

I think there is some relevance to this thought. if you could pump with a 10 stage compressor the risk would continue to go down. You are pumping 200 bar with 3 stages and that's around 70 bar perstage avg. I know its not like that but perhaps we should look at it like 1st atage is X4 and the next is X 10 and the next is X5. the X10 is a large as far as the compression and the heat generated. The more compressor stages the less increase per stage.

 

[abnfrog]

no he did not say there was a kit he said there was a NITROX specific block for compressing more than 21 % what that entailed I didn't ask .... he did say it was unsafe to use a NORMAL compressor .........