Home brew nitrox

[CD_in_Chitown]

Pescy, I don't know who raised you but you need a new attitude.

Discussion over.

Yeah, how dare you contradict someone with facts instead of ad-hominem attacks! This is SB don't forget.

 

[rjack321]

There is not a single verifiable fact in Mr pescador's post - just vague "I talked to" crap. Ultrachem makes/sells all 3 oil types and they advocate synthetic triester (751) for CBing. Shall I forward you the email discussion I had with them? Bauer has done more research on oil than anyone and to my knowledge they aren't recommending food grades for CBing either.

Oh and by the way the "resistant to oxidation" line is BS. The flash point for 455 is 464F while 751 has a higher flashpoint of 520F.

Real data is here:
http://www.ultracheminc.com/products.asp

That's all I asked for and Mr Pescy - rather than having a logical discussion about real data, gave me a line of condescending BS - as he generally does.

 

[pescador775]

Rjack, you probably don't realize that I spent weeks researching compressor oils. I've looked at company data on the web and obtained data directly from the oil manufacturing companies themselves and even companies like Great Lakes Chemical who make the additives for some of the oils. I've reviewed every test of every parameter that these companies are willing to supply. All of these companies are populated by people who may or may not have access to some data or general information. I have not found any who are qualified to analyse their own data for purposes of making recommendations WRT NITROX blending. To them, it is black magic. Therefore, it is up to people in the diving community to arrive at whatever conclusions may be relevant. The chemist who backed UBS in recommending PAO oils was a starting point. From there, I spent several weeks corresponding with an engineer who was investigating air contamination incidents. From there, I reviewed every type of oil performance criteria and testing which surfaced during the dialogue, some of which I was unaware. I am convinced that PAO, H1 oils are superior for use in NITROX compressors. The problem I have with UBS is that they will not reveal the source of the EZ 1000, same with CF 2000. Rumor has it that a guy in Florida mixes the stuff in his basement. However, the recently developed Omnilube 455 is a truly superior oil from the standpoint of oxygen stability wear prevention and lubricity. Roughly speaking, it is twice as good as EZ1000 for NITROX and general lubrication. It does not have the solvent properties of 751 or other diesters so 455 will not carry away carbon as efficient. However, 455 should not form much carbon in the first place. Flash point differences are not relevent for typical compressor use. That is because the flash point of 455, although slightly lower than 751, is still plenty high for average compressor use. When pumping NITROX, resistance to oxidation is the important characteristic and 455 is three times as resistant to oxidation as 751.

In that vein, I spoke to Bauer, Norfolk. Several individuals there said "we don't support NITROX". I can tell you they haven't a clue even as to what a "food grade" oil is, and have no knowledge whether their own branded oil or any other would be suitable for the purpose of lubing a Bauer compressor which is pumping NITROX. It appears they are scared of the stuff, probably warned off by counsel or management in Germany.

 

[pescador775]

More oil info:
Since my last post on this board it has come to my attention that ExxonMobil has published new toxicological data for MOBIL JET II turbine oil. This MSDS indicates that JET II turbine oil has passed all tests including INHALATION tests with minimal toxicity. My conclusion is that turbine oil can be used safely in a Kidde or Stewart Warner breathing air compressor equipped with modern filtration system. Inhalation tests on rats at levels of 5000 mg/m3 showed no ill effects.

http://www.host1.exxonmobil.com/psims/psims.aspx

I continue to believe that food grade, Ultrachem Omnilube 455 is the best oil for a Bauer NITROX compressor so that has not changed. This oil is sold in small quantities (1 gal) by NUVAIR. When considering a food grade oil for the Kidde compressor I recommend Omnilube 32/46.

Research of diester oils such as Chemlube 751 indicate that they contain trace amounts of toluene which is added to the basestock by the mfgr and not completely removed later in the production process. I believe this explains some things about the carbon monoxide alleged to have been produced in some air compressors when operated in hot climates. It is possible--but I have no proof-- that the flash point data for these oils do not take into account the conditions which occur in an air compressor; eg, should toluene gaseous vapor be released in the hot, turbulent environment inside an air compressor cylinder and, if so, that this volatile gas acts as a "fuze" which in turn causes the oil mist to flash burn at lower temperatures than published by Ultrachem, Anderol, et al. Of course, this hypothesis assumes that 751 or similar was used in the suspect compressor in the first place. It is also possible, but not known to me, that a mineral oil was involved in compressor incidents where CO was detected. However that may be, the release of toluene alone, and the pumping this hydrocarbon into a SCUBA tank, is known to be quite hazardous to the diver. Lastly, it is clear that either event is unusual and those that do occur are usually attenuated by the filtration system of the compressor. Under average conditions of NITROX or air handling, it may be irrelevant whether a diester or PAO (food grade) oil is used. A lot of people use pthalate diesters in their compressors and live to tell about it. Generally, these oils give excellent service. However, where compressors are used to pump NITROX--where compressor temps are high--it would seem prudent to change oil more frequently and to maintain filters regularly. For compressors with small sumps (1/2 ltr) which are pumping NITROX, I am suggesting that diester oils be changed at 20 hours and PAO oils at 30 hours. For machines with larger sumps these intervals could probably be extended accordingly.

 

[pescador775]

This is my last "condescending" post on the subject. However, I am willing to offer many more on different subjects. I had some fun at rjack's expense but may have stepped on my toes in the process. One such error; earlier on I mentioned Chemlube 751 as a "triester" where it is obviously a diester. Chemlube 800 is a triester. Scubaboard is attended by many in industry. Yet, with rare exceptions, we never hear any of the good stuff from these people. From them, we hear everything is rosey, there are no problems, no scandals s, no mistakes, "exploding aluminum cylinders, recalled regulators, leaky masks are safe and you divers are guilty of human error, we make no mistakes; We don't fix prices nor do we sell stuff under the table to discounters. We have your interests at heart." As consumers, our work is cut out for us. This oil flap is just one such area of consumer interest.

 

[BarryNL]

This question is for all those who mix their own nitrox. I want to start blending my own mix of EAN. I have the basic and advanced nitrox certs. I also have a portable Nautica compressor to top off with, and an O2 sensor. Are there any courses out there that teach you exactly how to fill your own bottles with EAN? I have worked in a LDS and have filled hundreds of bottles with air, so I've got that part down. What I want to know is how to blend different mixes as well as what not to do. I also want to fill my own Argon bottle. I am a welder and have the big bottles of O2 and Argon. Thanks for any info.

PADI/DSAT has the Tec Gas Blender course which, er, teaches you to blend tec gasses (plus oxygen service your own equipment).